Ideas Blog

NZ’s National Security Draft Long-term Insights Briefing (LTIB): Excellent Progress but Scope for Improvement

Matt Boyd, Nick Wilson, Ben Payne

(12 min read)



  • The draft NZ National Security Long-term Insights Briefing (already informed by a public survey) is currently out for public consultation.
  • The briefing identifies national security trends, potential scenarios, and provides additional detail on six important national security issues: Disinformation, Hacking and cyber attacks, Transnational organised crime, Foreign interference and espionage, Terrorism and violent extremism, Pacific resilience challenges.
  • The briefing identifies ten features that could help progress to a secure future for New Zealanders.
  • This post details our three suggestions to improve the briefing: (1) important improvements to future iterations of the public survey, (2) the need to explicitly articulate the extreme tail risks of each major trend identified, and (3) the importance of signalling a move towards an integrated and comprehensive National Risks Assessment.

The Draft NZ National Security LTIB (November 2022)

The draft NZ National Security Long-term Insights Briefing (LTIB) has been presented for public consultation.

The LTIB was produced by a group of nine government agencies that are responsible for protecting NZ from national security threats.

The briefing draws on information obtained from communities, businesses, and government agencies. This includes information from a survey, which we discuss below.

The LTIB examines key global trends across the next 10 to 15 years, some national security risks, and challenges ‘of concern’ and how they might change across time.

Four key global trends are identified:

  • Increasing competition and continued deterioration of the international ‘rules-based order’
  • Transformational technology changes
  • Climate change
  • Covid-19 and future pandemics

Three plausible global scenarios are outlined:

  • Continued decline: continuing armed conflict, competition for resources and the impact of malicious actors
  • Dramatic decline: spreading conflict, unmitigated climate impacts and the possibility that ‘a nuclear weapon’ could be used
  • Optimistic scenario: including international collaboration, technological innovation, and investment in climate adaptation.  

The draft of the National Security LTIB focuses on six security issues:

  • Disinformation
  • Hacking and cyber attacks
  • Transnational organised crime
  • Foreign interference and espionage
  • Terrorism and violent extremism
  • Pacific resilience challenges

Each threat is profiled and followed by sections describing ‘what we expect to see in the next 10-15 years,’ and how NZ can be ‘preparing for the future now’.

The LTIB rightly acknowledges the competing demands of, ‘investing in response to current crises and building our capacity and capability to respond to future challenges, including preparing for high impact but rare events.’

The briefing concludes with Ten Features that could support a bright future for national security. 

  • Transparent accessible public information
  • National security sector stewardship
  • Strengthened political leadership on national security
  • International partnerships that grow and strengthen our national security
  • A national security sector that reflects the diversity of our nation and is adaptable and capable of responding to future challenges
  • Open debate among, and advice from, experts outside of government
  • Active and engaging media coverage
  • Recognising and working with partners outside of government
  • Communities that feel enabled and empowered to engage with the national security sector
  • Trusted and accountable institutions

Our feedback on the draft LTIB

The NZ Government and its officials are to be congratulated on this excellent draft National Security LTIB. This work represents a substantial move forward in thinking in this domain. Nevertheless, we take this consultation opportunity to offer ideas for further developing this document and for its future iterations – as outlined below.

1. Scope for Improving Subsequent Surveys of the Public

The survey of public opinion conducted by Ipsos provides a lot of interesting information. We understand that the survey questions were chosen to be consistent with global research undertaken by Ipsos. However, as a basis for decision-making the survey has some shortcomings which should be addressed in future iterations or through other public engagement channels.

Survey results show that New Zealanders want more information about the threats the country faces. The LTIB could specifically advocate for additional research and knowledge generation/dissemination about risks and threats that are poorly understood. The survey also revealed that the NZ population wants the opportunity to comment on national security issues (we discuss this below).

Potentially fruitful areas for improvement in the next iteration of the survey are as follows:

Firstly, many survey respondents indicated that they wanted more information about national security issues. This begs the question of whether their responses are fully informed responses or merely guesstimates based on partial information.

Secondly, the descriptions of some threats are either too broad or too specific.

  • For example, one of the items included was ‘nuclear, chemical or biological attack somewhere in the world’. The use of a single nuclear weapon could escalate into nuclear war, the effects of which NZ would not escape (see our recent study here: [1]; and previous NZ work on nuclear war impacts here: [2] [3] [4] [5]). However, it was not clear whether respondents were to consider threats such as an all-out NATO-Russia nuclear war and any ensuing global nuclear winter, or whether respondents were contemplating something as localised as chemical attacks in the Syrian conflict. The potential impacts are vastly different – since some nuclear war scenarios could potentially result in the permanent collapse of civilisation.
  • Some threats as described were possibly overly specific. For example, ‘breakdown in national infrastructure due to attack’ might have implied a direct cyber or physical assault on infrastructure. However, a breakdown in national infrastructure could occur due to the cascading impacts of other threats, such as Northern Hemisphere conflict and abrupt NZ trade isolation, or the impacts of a large supervolcanic eruption, devastating solar flare, or nuclear war. The more causal paths leading to an effect, the more probable (and threatening) a scenario might be ranked by respondents.
  • This problem of ‘scenario choice’ has important implications for public engagement on risk and we discuss it in our recent paper on national risk assessments and national risk registers [6].

Thirdly, the importance of a threat is often taken to be some product of two factors, probability and consequences, which together generate an estimate of consequences in expectation.

  • Some survey questions clearly asked about consequences, ‘IF these were to happen… which do you think poses the greatest threat’. However, other questions used ambiguous phrasing, ‘how real do you feel the threat is of any of the following happening…’ It is unclear whether respondents would interpret this as asking about probability, consequences, a combination of probability and consequences, or something else. It is particularly ambiguous given that the word ‘threat’ is also used in the question about consequences. If interpreted as probability by respondents then the latter question reveals nothing about the salience or importance of a risk, this could only be deduced by combining responses to both questions. However, when presenting the following matrix of government capability vs ‘level of perceived threat’ it is the ambiguous item that is graphed. The problem is that a respondent might feel there is a high probability of something happening, but that the consequences are trivial. In which case ‘Act and Improve’ (see ‘Survey Report’ p.10) is the wrong response. There is therefore a strong case for a future survey that accesses more decision relevant risk information across a more comprehensive spectrum of risks. The LTIB should ideally indicate aspiration to commission or conduct such survey work.
  • The survey might also imply (if we interpret ‘how real do you feel the threat is of any of the following happening’ as accessing consequences in expectation, not merely probability) that violent conflict in NZ, a nuclear ‘attack’, or breakdown of infrastructure in NZ are more salient (deserve more focus moving forward) than, for example, terrorism and violent extremism, since the respondents felt that the government was already well placed to deal with the latter threats. Importantly nuclear attack (the LTIB should be far more explicit that major nuclear war is possible, not merely an ‘attack’), breakdown of infrastructure and violent conflict in NZ are not independent risks.

Future iterations of the survey could be conducted with improved wording, after a public information campaign, and include the full spectrum of risks.

We have previously argued for a two-way communication platform connecting information gathered through a comprehensive National Risk Assessment (all risks, not just national security, see below) with a portal for ongoing public and expert feedback and scrutiny [6]. A comprehensive LTIB could signal aspirations to develop such a tool, promoted by the media, and thereby effect the goals of the previous paragraph as well as advance the desirable national security features of:

  • Transparent accessible public information
  • Open debate among, and advice from, experts outside of government
  • Active and engaging media coverage
  • Recognising and working with partners outside of government
  • Communities that feel enabled and empowered to engage with the national security sector

2. Suggestions for completing the Draft National Security LTIB

We agree with the four trends outlined in the LTIB. Increasing global competition, technological advance, climate change and pandemics are growing threats. But each of these four trends has an associated global catastrophic or existential threat to humanity and these extreme tail risks should be acknowledged and analysed because they would be unbearable.

Those that study the largest risks the world faces often prioritise risks from nuclear war, artificial intelligence not aligned to human values, extreme climate change, and engineered pandemics (eg, well summarised in work by Ord [7]). These four risks correspond with the four trends outlined. However, the wording of the LTIB could be clarified to specify that each trend has a globally catastrophic form, or even a tail risk that is an existential threat to humanity. NZ is in a privileged position in that it may well suffer less direct consequences from some of these threats (nuclear war [1], supervolcanic disaster [8]), however as our research has indicated, NZ may be extremely fragile to the cascading consequences of such major threats [1].

Looking to the results of the survey, of these four trends, ‘health epidemic’ tops the list of NZ citizens’ concerns (however they are interpreted). This is probably appropriate, especially if including concerns around natural pandemics (ongoing Covid-19 harms and newly emerging pandemic diseases), bioweapon pandemics, laboratory accidents, and gain-of-function engineering. Nevertheless, the LTIB could be more explicit that the scope of pandemic threats is not limited to influenza pandemics or Covid-19-like events and future biological threats could be extreme (even being existential threats to humanity [7]).

It is particularly appropriate to include misinformation as a major national security risk. A healthy information environment that facilitates accurately informed public discussion on threats is essential, and underpins the ability to analyse, prevent, respond to, and recover from all other threats.

Although the LTIB profiles five important threats other than misinformation, the omissions are interesting. It is not entirely clear why some threats depicted in the four-quadrant figure (public survey results p.10) were selected for inclusion and others for exclusion from further discussion in the LTIB.

  • For example, domestic terrorism is rated by survey respondents as a moderate threat, that is well-handled by the government at present. Whereas nuclear/biological/chemical attack is rated as at least as threatening, but poorly addressed by the government (noting the ambiguity we discuss above over probability, consequences, and consequences in expectation in the survey).
  • Some emphasis could be placed on unknown threats. There are likely many risks both internal and external to NZ and indeed to government itself that we do not know about yet (eg, pandemics from synthetic bioweapons was not appreciated as a future threat before genetic engineering technology was invented). General resilience building may be able to mitigate the impact of such unknowns.

The LTIB acknowledges the existence of tension between prioritising resources for current risks (eg, misinformation) vs future risks (eg, nuclear war). This tension is a strong argument for ensuring a methodology to systematically analyse national risks (present and future, national security risks and other risks) in terms of the ‘level of threat’ and how ‘concerning’ they are (with appropriate operationalisation of these concepts, making clear what kinds of wellbeing, assets, and values – now or in the future – are being considered) and make both the methodology and findings of the analysis public, so the public can have a say in resource prioritisation decisions.

Finally, although ‘natural disaster in New Zealand’ could be considered a national security threat, or at least a national risk, then relevant ‘natural disasters outside NZ’ should be included, such as supervolcanic eruptions or coronal mass ejections (solar flares). However, we suspect that an information campaign would be needed to obtain useful public engagement on such risks (given the technical complexities).

The LTIB states that, ‘New Zealand’s approach to building resilience in our society and preventing the spread of disinformation needs to be comprehensive and long term.’ We concur and this should be the case for every threat ‘of concern’. It is also relevant to particularly catastrophic threats.  For example, nuclear conflict that rises well beyond the use of ‘a nuclear weapon’ and leads to a possible nuclear winter. A multi-decade (long-term!) strategic plan to build NZ’s resilience could be envisioned as an incremental ongoing project. This could be seen as a priority given NZ’s privileged (high-income remote island nation), though fragile, position in greater context of humanity.

Unless the probability of a risk is zero then it will (by definition) occur given a long-enough timeframe. If the probability is one percent per annum (as is plausible with several global catastrophes eg, nuclear war [9]) then it is likely to happen this century if preventive measures are not scaled up. If each successive LTIB only looks 10 years ahead, then each may be blind to such risks. Some generation at some point must prepare for these risks, or all will suffer.

3. The National Security LTIB should signal a move towards a comprehensive National Risk Assessment

Analysis of national security threats needs to feed (along with other risk issues, eg, natural hazards, existential risks) into a National Risk Register that is aligned with a National Risk Mitigation Strategy & Plan, which includes a methodology for prioritising resources to the greatest threats.

The LTIB takes the perspective that national security issues are by and large agential threats, ie, those where someone or some group poses a threat. Other entities in NZ allegedly deal with other kinds of threats, such as natural hazards and other non-agential threats. However, this arrangement risks leading to siloed focus on historical threats with the result that risks that are less familiar to policymakers, emerging risks, and interacting risks slipping between the gaps. How these entities nest and communicate is very important, because as was highlighted in the UNDRR Framework for Global Science In Support of Risk-informed Sustainable Development and Planetary Health (2021) siloing is paralysing risk mitigation action across the entire spectrum of risks (agential and non-agential)

We think that risk management at a national level in NZ would benefit from a move towards an integrated risk approach. Stewardship and partnerships, as indicated in the ‘ten features’ will be important, but these partnerships should include those outside traditional ‘security’ silos, and there should be an overarching entity accountable for analysis, communication, and resource allocation recommendations across all national risks. This entity could be a Parliamentary Commissioner for national/extreme risks [10], or some other office.  

Part of the argument for the national security LTIB signalling the merits of moving to an integrated risk approach rests on global trends towards such approaches. We note that many countries publish a National Risk Register that includes both natural and agential risks. We also note that the distinction between natural and human-induced is often vague. International frameworks such as the Sendai Framework for Disaster Risk Reduction are moving away from such a distinction, with the UN General Assembly deciding to hold a ‘midterm review of the implementation of the Sendai Framework 2015-2030.’ As part of this process, the Global Platform on Disaster Risk Reduction 2022 held a plenary session on ‘beyond natural hazards – operationalizing expanded scope’, and argued in favour of the need to take into account anthropogenic risks and take more preventive action.

The future will likely see the Sendai Framework integrating risks traditionally seen as ‘natural’ and threats perhaps traditionally seen as ‘security’ issues. The plenary session noted that there was a risk of being, ‘blind to the full range of global catastrophic or existential risk scenarios’.

In addition to the Sendai mid-term review, the UN Secretary General has delivered Our Common Agenda (2021), a report that highlights the need to do things radically differently in order to avoid existential and catastrophic risks created as a result of human activity. Additionally, The UN Declaration on Future Generations (part of the Our Common Agenda programme) has published an Elements Paper, which explicitly talks about the need to mitigate extreme risks as a priority to protect future generations. NZ’s LTIBs could look much further than the 10-15 years that concerns the present generation.

In addition, the change in emphasis towards greater integration is reflected in the Framework for Global Science co-sponsored by the UNDRR and ISC and supported by the IRDR IPO in Beijing. Overall, the document takes stock of recent developments in disaster risk science and provides a compelling set of directions for research and scientific collaboration for a more holistic and collaborative approach to understanding and managing risks. The framework highlights the rapidly changing nature of risk dynamics, recognizing that a lot of risk work to date has been hazards focused with specific mitigating actions for specific hazards. However, ever increasingly the risks are complex, systemic and interconnected/cascading (See Framework for Global Science Section 5.1, Priority 1).  A concern is that we may remain locked into traditional framings of risks and therefore, overlook interacting, compound, and cascading risks, and fail to effectively manage/plan for catastrophic and existential risks.

These are the arguments for the LTIB signalling that it is part of a future integrated national risk assessment and risk register. This would circumvent the issue of trying to decide what is a ‘security’ risk and what is not, and would help to avoid the problem of institutional silos and would help foster effective communities of practice. To even begin to address the issues of concern, the relevant risks must be included in the analysis.

The LTIB should recommend resources are dedicated to monitoring the four trends identified, but also resources should be committed to acknowledging, analysing and managing the extreme tail risks associated with each trend, in particular those risks that would be unbearable (ie, major nuclear war, powerful unaligned machine intelligence, extreme climate risks (either 6 °C+, or ecological feedforward cascades), and biological engineering of pathogens.

As the most isolated temperate land mass in the world, NZ should be particularly concerned about trade isolation as a severe risk. If any of the extreme scenarios just listed were to manifest, NZ may be the first to be dropped from stressed global shipping or a collapse in air transportation. Such effects could also be brought on by supervolcanic eruption, massive solar flare, large asteroid impact, or a range of other scenarios.

A comprehensive National Risk Assessment would also provide decision-relevant information for rational prioritisation of resources. This is a direction that we believe the National Security LTIB should signal that decision-makers ought to be heading.

Prioritisation decisions are often made within government departments, but shifting resources across government is harder, but more important to do. Areas where NZ is already doing reasonably well probably do not need a lot of extra resourcing (eg, epidemics/pandemics [11], domestic terrorism). But areas where it is perceived we are poorly prepared warrant extra focus, eg, misinformation and impacts of nuclear war/nuclear winter.

The neglectedness of some risks means that investment there will reap low-hanging fruit, while in contrast there are likely to be diminishing returns investing further to mitigate threats NZ is already competent in managing. Government should conduct cost-effectiveness and cost-benefit analyses across national security risks and intervention options (eg, there is scope to significantly advance preliminary work we have done on the cost-benefit of pandemic prevention [12] now that we have Covid-19 experience – this kind of approach can be applied to other threats).

We commend the gestures towards institution building presented in the ten features. However, those writing the LTIB are likely to each exist within one of the national security silos, and each sees what they are familiar with. Other silos exist in the natural hazards domain and yet other hazards and threats may fall between jurisdictional silos. NZ therefore needs a comprehensive National Risk Assessment that integrates natural, security, global catastrophic and existential risks. The LTIB should indicate that this is a goal worthy of pursuing, thereby ensuring there is appropriate responsibility and accountability for foreseeing, assessing, preventing, and mitigating extreme risks that cut across the traditional silos of government, including global risks where indirect harm could be catastrophic for NZ [1].


1.         Boyd M, Wilson N. Island refuges for surviving nuclear winter and other abrupt sunlight-reducing catastrophes. Risk Analysis (in press).

2.         Preddey G, Wilkins P, Wilson N, Kjellstrom T, Williamson B: Nuclear Disaster, A Report to the Commission for the Future. Wellington: Government Printer, 1982.

3.         Green W. Nuclear war impacts on noncombatant societies: An important research task. Ambio. 1989;18:402-406.

4.         Green W, Cairns T, Wright J. New Zealand After Nuclear War. Wellington: New Zealand Planning Council, 1987.

5.         New Zealand Planning Council. New Zealand after Nuclear War: The Background Papers. New Zealand Planning Council, 1987.

6.         Boyd M, Wilson N. Assumptions, uncertainty, and catastrophic/existential risk: National risk assessments need improved methods and stakeholder engagement. SocArXiv 2022;(5 August). Doi: 10.31235/

7.         Ord T. The precipice: Existential risk and the future of humanity. Bloomsbury. 2020.

8.         Wilson N, Cassidy M, Boyd M, Mani L, Valler V, Brönnimann S. Impact of the Tambora Volcanic Eruption of 1815 on Islands and Relevance to Future Sunlight-Blocking Catastrophes. Research Square (Preprint) 2022;(10 October).

9.         Hellman M, Cerf V. An existential discussion: What is the probability of nuclear war? Bulletin of the Atomic Scientists. 2021;(18 March).

10.       Boyd M, Wilson N. Anticipatory Governance for Preventing and Mitigating Catastrophic and Existential Risks. Policy Quarterly. 2021;17(4):20-31.

11.       Boyd M, Baker MG, Nelson C, Wilson N. The 2021 Global Health Security (GHS) Index: Aotearoa New Zealand’s improving capacity to manage biological threats must now be consolidated. The New Zealand Medical Journal (Online). 2022:89-98.

12.       Boyd M, Mansoor O, Baker M, Wilson N. Economic evaluation of border closure for a generic severe pandemic threat using New Zealand Treasury methods. Aust N Z J Public Health. 2018;42:444-446.

Islands and global catastrophic risks: a seminar at the Cambridge Centre for the Study of Existential Risk

Reconstructed temperature anomalies following the 1815 Tambora eruption indicate islands in the Southern Hemisphere experienced statistically significantly less temperature drop than those in the Northern Hemisphere (Wilson et al 2022, preprint)

Seminar 21 Oct 2022

Ahead of our forthcoming Aotearoa New Zealand Catastrophe Resilience Project, I presented a seminar at the Cambridge Centre for the Study of Existential Risk.

You can listen to the audio of the seminar here (90 min total, question time with the CSER audience begins at 58:30).

The slides associated with the presentation can be downloaded here.

Introducing the Aotearoa NZ Catastrophe Resilience Project

This post briefly introduces the Aotearoa NZ Catastrophe Resilience Project, our team including exciting new hire Dr Ben Payne, and outlines the aims, methods, and timeline of the project.

Why this project?

Global catastrophic risks include nuclear war, extreme pandemics, and supervolcanic eruptions, among other threats. Research, and recent experiences with disasters such as the Covid-19 pandemic and Russian invasion of Ukraine, indicate that should global catastrophes eventuate, the cascading global impacts could be severe. The consequences could be devastating for Aotearoa NZ, plausibly making it difficult to sustain industrial society. This runs counter to some views that ‘safe havens’ like NZ or Australia might be relatively less impacted in some global catastrophes.

The risk is that a major catastrophe disrupts climate, trade, or other global systems, to the point that industry is unable to function, leading to massive food, energy, manufacturing, and societal disruption.

The project draws inspiration from the concept of island refuges for mitigating existential risks to humanity. A suitably robust island might increase the probability that humanity survives even the greatest global catastrophes.

Project Aim

To understand the impact representative major global catastrophes might have on Aotearoa NZ, for example a Northern Hemisphere nuclear war. To deduce adaptive strategies and plans that might mitigate these effects, ensuring that industrial society can continue.

Project Team

The project team consists of three co-investigators. We will collaborate with Think Tanks, Academic Researchers, Policy Professionals, Industry, and the Public Sector through the 12-month duration of the project.

Dr Matt Boyd

Matt is an independent researcher who completed his PhD in philosophy. He founded Adapt Research in 2015. Matt has researched health, technology, and catastrophic risk for a decade and published over 40 peer-reviewed academic papers. His recent work has focused on national risk processes, nuclear winter, and global health security.

Professor Nick Wilson

Nick is a research professor of public health with research interests that include refuges to mitigate pandemic disease and nuclear war. Nick contributed to work for the Commission for the Future on Nuclear Disaster as far back as 1982. He has over 500 Medline-indexed research publications.

Dr Ben Payne

Ben is an experienced risk professional who completed his PhD in geography. Ben was Lead Scientific Officer with the Global Risk Research-Agenda Development Group of the UNDRR/International Science Council in producing A Framework for Global Science. He has also worked with Massey University’s Joint Centre for Disaster Research.


The project will begin in November 2022. Initial planning days will invite advice from risk professionals with established interests in global catastrophe and Aotearoa. Following planning there will be four phases:

  • Phase I will consist of the development of a National Risk Assessment risk profile for a representative global catastrophe (nuclear war/nuclear winter).
  • Phase II will involve workshops to assess knowledge gaps with respect to the risk profile, and design mixed method data collection using surveys and interview methodology. Some of these tools will be based on the 1987 NZ Nuclear Impacts Study.
  • Phase III is where we’ll reach out and survey knowledge holders across industry, the public sector and academia, including interviews. The aim is to collect data that paints a rich picture of the likely impacts of nuclear disaster on NZ society and industry, along with crowdsourced adaptive responses, mitigation strategies, and possible plans.
  • Phase IV will involve further workshops and a Delphi process to analyse the collected data and prioritise mitigation measures, this will include identifying those that might enhance business as usual.
  • Findings will be produced in the form of risk register entries, research papers, policy recommendations, and shadow Ministerial briefings.

Project Goals

The goal is to generate productive discussion, concrete solution ideas, and map a pathway to ongoing and robust analysis of global catastrophic and human existential risk and its relationship to Aotearoa NZ. We aim to connect our work in logical and, where possible, generalisable ways with catastrophe resilience work being undertaken across other island jurisdictions, with potential to leverage synergies with continental Australia, Tasmania, Indonesia, or others, in the future.

Islands, nuclear winter, and trade disruption as an existential risk factor

This is a link post to our new long-read on nuclear winter and abrupt sunlight reducing scenarios.

Purpose: In this long-read we provide a summary and extended commentary on our recent paper: Island refuges for surviving nuclear winter and other abrupt sun-reducing catastrophes (available as a pre-print via the link). We demonstrate how this research could help direct efforts to reduce the risk from catastrophic sun-blocking scenarios and suggest some next steps to safeguard humanity from these types of existential threat using New Zealand as a case study. 


  • Abrupt sunlight reducing scenarios (ASRS) such as nuclear winter or volcanic super-eruption are plausible and could have serious consequences for climate and food production. 
  • It is often thought that some Southern Hemisphere islands might resist the more severe impacts of these winters. 
  • We find that some locations could likely produce enough food in a nuclear winter to keep feeding their populations, but food supply alone does not guarantee flourishing of technological society if trade is seriously disrupted.
  • The potential disruption to industry and society caused by serious trade collapse could be severe and cause deindustrialization of societies. 
  • It is problematic to assume that locations such as New Zealand and Australia might survive catastrophes such as nuclear winter with their institutions and technology intact – without major upgrades in their levels of resilience. 
  • This has implications for the future of humanity and human civilisation, given the existing assumptions about Southern Hemisphere islands. 
  • Many nations might be advised to pursue resilient foods to mitigate ASRS, but New Zealand and Australia might focus on resilience measures for preserving transport, energy, manufacturing, and industrial inputs in the absence of global trade. 

You can read the full long-read on the EA Forum by clicking here.

NZ and Global Crises: Brief reply to Reuben Steff

This short piece is a reply to Dr Reuben Steff’s insightful new article about geopolitics and strategic risks to New Zealand on Newsroom:

Great piece Reuben, and I largely agree with your assessment. The confidential nature of New Zealand’s National Risk Register is frustrating especially for those wanting to contribute to research, idea generation and strategy on catastrophe resilience. It seems that the decision of the government has been to keep ‘bad news’ quiet rather than foster a national culture of strategic planning and resilience (compare Sweden, Switzerland, Netherlands, Norway).

There was some public work in the 1980s on nuclear impacts (which applies to other hazards too such as trade isolation, great power war, climate altering volcanic eruptions, etc). Recommendations for a ‘Phase II’ project to understand vulnerability and resilience were tabled but killed by security officials. Apparently, it was in the best interests of New Zealand to keep resilience thinking secret or non-existent. Yet you don’t buy house insurance because you’re planning for a house fire, you buy it because a fire would be unbearable.

Given that this information is not public, our new project (Aotearoa NZ Catastrophe Resilience Project) looks to start to create ‘modules’ similar in nature to those that might be found in National Risk Register but covering catastrophic and existential threats. Societal prioritisation processes across all risks, are only possible if the thinking is transparent. We further plan to begin crowdsourcing strategic solutions from industry, the public sector and academia.

There are those beyond NZ who care about NZ’s resilience. These are found in the long-termist community that values humanity’s future. An impartial moral stance sees the most worthwhile thinking to be location agnostic, and a rationalist perspective seeks (and finds in eg NZ) optimal targets for developing human resilience. Leveraging this thinking, and its local proponents, could lead to a think tank on NZ resilience issues (eg your Aotearoa NZ Resilience Initiative) catalysed by proof of concept from this and earlier work. We also favour a ‘Parliamentary Commissioner for Extreme Risks’ to look across this set of issues.

Regional collaboration will be important if there is decay of global interconnectedness. New Zealand should re-evaluate its regional trade mix. In particular, NZ should probably ensure complementary rather than competitive industry with Australia.

This exciting new work to try to uncover vulnerabilities and crowdsource solutions for 2023 rather than 1987, and using processes such as Delphi to generate a ‘big 10’ approach, could be insightful. There are some obvious contenders, for example diesel is still needed to feed the country (production, processing, distribution). The recent murmurings about onshoring fuel stockpiles are initial token gestures (eg converting 20 days operational reserve into 24 or 60). This might buffer a 90-day trade hiccup, not a years-long disconnection. Local production, or alternative infrastructure would be better (think Southland green hydrogen, increased production of biofuels – it is disappointing to see Marsden Refinery closed and Z-Energy pulling back from biofuel production at the same time).

But I don’t want to prejudge solutions, our project is taking some initial steps to start extracting them, and hopefully generate some interesting leads which the funder might want to pursue via think tank in a Public/Private/longtermist-NGO collaboration. I welcome anyone interested to get in touch.

‘The End of the World is Just the Beginning’ and the value of a NZ National Catastrophe Resilience Strategy

Book Cover: Harper Business, 2022

TLDR: This post surveys Peter Zeihan’s new book on demographic trends and geopolitical strife, in which he warns of future severe disruptions to global trade, and the likelihood of industrial collapse in many regions. I then leverage off Zeihan’s book (and some similar recent work we’ve done on global catastrophic risks) to suggest a suite of other risks/risk factors that could all manifest with the same catastrophic trade isolation for New Zealand (including nuclear war/winter, supervolcanic eruption, extreme pandemic, solar flare, asteroid/comet impact, conventional war, etc). I briefly introduce an upcoming project to investigate these issues and inform a possible future New Zealand National Catastrophe Resilience Strategy (or similar). I call for interested contributors to get in touch to learn more.

Demography and geopolitics

An international demographic time bomb that is already underway, interacts with US retreat from globalisation, and this sets off a cascade of trade uncoupling that sees only the US (NAFTA) and a few very select locales maintain industrialisation.

This is the scenario Peter Zeihan contemplates in his new book ‘The End of the World is Just the Beginning’ (Harper Business, June 2022). Zeihan uses this scenario, which he argues is very plausible, to present an extremely engaging overview of the interconnected dependencies of the industrialised world, their historical origins, and how they will end.  

The lesson is that immense global interdependencies across transport, finance, energy, industrial inputs, manufacturing, and agriculture are extremely fragile to the scenario he describes. Unmitigated the outcome could be deindustrialisation, and hence de-civilisation for much of the world.

The Scenario

Zeihan’s forecast scenario is one where the United States determines that the world Order (with a capital ‘O’) that it helped engineer after World War Two was useful for keeping the Soviet Union at bay but since the fall of the Berlin Wall is no longer in US strategic interests (Zeihan’s final manuscript was completed days before Russia invaded Ukraine). The US withdraws its policing of global trade routes, setting off a wave of trade insecurity.

The US move is amplified by a demographic transition that has already past the point of no return in many countries, namely the retiring of baby boomers, who cease productivity, extract capital from the economy, and leave insufficient children in their wake to supply labour and consumption. The impact on China, which is averaging 1.3 children per couple, is particularly catastrophic, halving the Chinese population by 2070.

Zeihan notes that the ONLY high-development steady-demographic countries are: the US, France, Argentina, Sweden, and New Zealand, that’s ALL. Most countries will never return to 2019 stability and growth, and most have now lost the chance to even try to shift footing.


In this scenario, the world cannot assume that industrial technologies that reduce mortality and raise standards of living will continue to be supplied if trade collapses. Industry sustains the ability of many human settlements to remain where they are. For example, water management systems are essential for many cities in arid regions, and without industrial inputs there would be societal breakdown. If global flows of products and services and energy and food are interrupted, ‘political and economic maps will change’.

Zeihan argues that the US (with the cooperation of NAFTA partners Canada and Mexico) can shuffle things internally and supply all the material resources and labour that they need, along with the geography and means to defend it all.

Elsewhere de-globalisation means an ‘unravelling’. Zimbabwe and Venezuela are cited as examples, and much worse could happen (perhaps Sri Lanka is on the precipice).

‘Should something happen to the sustainability or reach of the industrial technology set, all of them will simply fade away-and take all their benefits with them,’ says Zeihan. Basically, if a country lacks the industrial inputs they need, then they can’t achieve the outputs. Deindustrialization would be much quicker than industrialisation.

Some selected highlights from Zeihan’s systematic and highly engaging discussion of the critical sectors are as follows:


Transportation is the ultimate enabler of industry (arguably it’s energy, but it’s all a bit chicken and egg and energy comes below). The world has become massively dependent on long-distance shipping, with logistics concentrated in a handful of mega-ports such as Rotterdam and Shanghai. Nowadays it is not just raw materials and finished goods that are shipped, intermediate products are shipped too and there may be hundreds or even thousands of intermediate steps products pass through.

Long haul transport is an early casualty in the scenario because it requires peace in all regions (and the absence of state piracy). It also requires diesel (which must also be transported). Small interruptions amplify to major interruptions due to the just-in-time logistical nightmare that is global shipping. Skill or capacity to adapt to failed arrival of commodities is lacking in many locales if transport fails. Rail, trucks, let alone horse carts, are completely inadequate to preserve the flow of goods enabled by modern long-haul container, and bulk, shipping.


At present the importance of oil for global industrial functioning cannot be overemphasized. Firstly, transportation (above) depends on oil. Protection of shipping lanes and other transport routes depends on oil. Zeihan compares renewables and electrification with oil and finds that although there are some emerging solutions these are too few, too slow, and not up to the task of replacing industrial energy needs (yet).

Furthermore, existing oil infrastructure (and any new build-out) depends on UK and US experts. Left to their own devices many states will struggle with oil, and countries such as Russia may struggle to maintain their existing pipelines due to shortages of capital, labour, and technical expertise.

A few weeks without oil and industrial civilization is screwed. This is why the EU requires countries to maintain a 60-day buffer of fuel supply, and Japan over 120 days. In New Zealand there is 20 days of operational reserve, although MBIE has made moves to increase this. However, none of these short-term buffers is actually a solution.

Industrial Inputs

Essential inputs to maintain industrialization include iron ore, copper, bauxite, as well as rare earths and many many other materials. Zeihan’s scenario forecasts the withering of Chinese industry (including smelting) as the demographic timebomb really hits, compounded by collapse of China’s over financed industrial build-out. The world has prepared to compensate for a weakened China in some areas, such as rare earths, where there are processing facilities on standby (eg in Australia), if the products can be successfully transported! But the loss of a steady predictable flow of other inputs would spell immense disruption and the book surveys in some detail the role and difficulties associated with a suite of key industrial inputs.

Zeihan notes that countries may individually be able to accomplish some steps in critical processes, but there are some very challenging steps that require specialised mastery. Solar panels and semiconductors require extremely pure silicon. Forging steel is harder than making rails. Zeihan argues that the world needs more smelting capacity. Places like Australia produce both iron ore and coal and could connect the dots, but there are still problems with transport and energy (see above).


Manufacturing has become a highly distributed, highly specialised process. A car might have 30,000 parts and hundreds if not thousands of suppliers and intermediate steps in the manufacturing process. Any disruption to any one supply chain could turn cars into expensive paperweights. Other manufacturing sectors such as lumber, electronics, semiconductors, machinery, pharmaceuticals, plastics, and so on, are all highly susceptible to disruptions in long-haul shipping, capital, labour, and expertise.


Any trade disruption would hit food supply hard. Firstly two-thirds of countries are dependent on food imports for calorie intake. But industrial inputs including raw stock (eg seeds), equipment, and industrial commodities must all be transported. Diesel, pesticide, and fertilizer (including sources of nitrogen, phosphate, and potassium) must all be sourced. Transport and refrigeration are needed. Zeihan predicts that large scale monoculture will give way to small scale polyculture.

Zeihan also talks about Finance, but I’ve skipped over that in the interests of brevity (however, it’s worth a read).

Relevance for New Zealand

Zeihan paints a detailed picture of the collapse of many regions of the world. However, he predicts US (NAFTA) success thanks to its demographic and geographic abundance and diversity. He also leaves room for other thriving regional networks if the right cooperation is in play. For example, Southeast Asia plus Australia and New Zealand. This is where Zeihan’s analysis intersects with a topic I’m particularly interested in.

Zeihan’s book is about US policy and world demographics. He doesn’t contemplate catastrophic risks to the US, such as major political instability, let alone supervolcanic eruptions (Yellowstone), immense solar flares, global conventional war, or extreme bioweapon pandemics. Nor does he consider nuclear war.

The reason I raise these potential catastrophes is because they all have the potential to cause the same kind of global trade meltdown and deindustrialisation as in Zeihan’s scenario, but in these cases the US/NAFTA may be particularly hard hit. This is especially the case for nuclear or volcanic winter where food production could collapse in North America. France, Canada, and the US may be the most agriculturally robust countries, once access to agricultural inputs and equipment are also considered (according to Zeihan), but these countries suffer some of the worst from sunlight reduction and crop failure in nuclear war modelling studies.

Under such scenarios the Australia-New Zealand dyad may be one of the few places on earth able to sustain functional industry, and probably only with careful planning and cooperation. No matter the proximal cause (demography, geopolitical unrest, pandemic, nuclear war, volcano) trade collapse requires a similar response.

We recently analysed the nuclear war (or other abrupt sunlight reducing) scenario and came to similar conclusions to those in Zeihan’s book. Australia and New Zealand have an agricultural buffer that might resist severe shock (both sunlight reduction and lack of some inputs), but resilience might be optimised by regional cooperation with the likes of Indonesia, the Philippines, etc. Our academic paper on ‘Island refuges for surviving nuclear winter and other abrupt sun-reducing catastrophes’ is currently going through the publication process, and I will blog separately on it when it appears, but the one line summary is that only eight island nations have sufficient food production under even ‘mild’ nuclear winter conditions but these include: Australia, New Zealand, Indonesia, and the Philippines, which like Zeihan’s ‘Southeast Asia’ set, could form an extremely complementary quartet (throw in PNG’s mineral resources and the likes of Vanuatu and the Solomon Islands excess food production).

It is not just our analysis of nuclear winter that has recently contemplated trade disruption and its impact on New Zealand. The Covid-19 pandemic and Russian invasion of Ukraine have highlighted many of these issues. Waka Kotahi have published an issues paper on freight and supply chain, MPI’s think tank Te Puna Whakaaronui has written on global food security, and an Office of the Minister for Energy Cabinet Paper addresses short-term issues for refined fuel supply. Some organisations have started to think through these implications in isolation. However, in the 1980s the New Zealand Nuclear Impacts Study explored this somewhat systematically but appears never to have been followed up with an actual strategy.

The question remains, how can New Zealand optimise its resilience to catastrophic trade disruption and what level of industrial civilisation could be sustained?

In one sense New Zealand is in the worst possible position, as the most remote temperate land mass in the world (if there is catastrophic geopolitical/global demographic disruption). In another sense it is in the best possible position as the most remote temperate land mass in the world (if there is nuclear or volcanic winter, or an extreme bioweapon pandemic). Regardless, the issues may be roughly the same.

What should New Zealand do?

What follows is not intended to be a set of recommendations or a plan, much more work is needed to identify and then prioritise the most important impacts. However, possible approaches can be conceived. For example, failure of transport might be aided by a plan to secure resources for coastal shipping, or a strategy of developing a hydrogen powered logistics fleet. Oil will be necessary (it is also an input to many products), and local production should be matched to a local refinery handling the appropriate grade. The present 20 days of refined fuel as operational reserve will be manifestly insufficient, and any suggestion for increasing reserve, and for storing it onshore (rather than offshore as at present) will help the transition (diesel should be prioritized).

Biofuel production facilities could be prepared and on standby. Hydroelectric power could be used to produce green hydrogen. Geothermal energy, and wind and solar could be further developed. Plans for how to prioritise energy for essential functions could be drawn up, cities can plan to down-power. Coal can be used. Nuclear can be investigated.

Overall, solutions that are the least technically challenging, and have the lowest probability of requiring imported commodities and expertise for maintenance should be prioritised.

That said, a critical part of such planning should be integrated cooperation with near neighbours, where shipping may still be possible (with locally owned ships and strategic use of limited fuels). This might occur among New Zealand, Australia, Indonesia, and the Philippines. Along with Papua New Guinea, this mix of countries holds a diverse, complementary, and possibly self-sustaining set of natural, human, and economic resources (akin to the NAFTA situation).

New Zealand will clearly not be able to manufacture everything it desires. The automotive industry might study the case of Cuba during its decades of trade blockade. On the other hand, use of woollen textiles and a growing textile industry might be encouraged. Machinery is needed for all manufacturing, and the Japanese and Taiwanese strategy of supporting a multitude of tiny facilities that machine, produce and supply customized parts could be developed. 3D printing can be harnessed provided there is access to input materials. Raw inputs such as bauxite, iron ore and rare earths could be traded with Australia (smelted and returned in the case of aluminium).

Agriculturally New Zealand is well-placed but could squander that advantage with poor management. Overfertilisation may have baked several productive years into the soil, but eventually these inputs will need reliable energy and transport. It might be in some cases that it is more efficient to move people closer to production (deurbanisation). Shifting planting (away from the margins) with large scale monoculture giving way to smaller scale localised polyculture could preserve variety, even preindustrial gardening can be highly efficient, though a sustainable plan for seed stock is needed. We’ve found in recent work that NZ exports of milk powder alone, if directed to the domestic market, could provide more than 100% of New Zealand’s caloric needs even under the severe modelled global conditions of a nuclear winter. However, no one wants to eat only milk.  

Regional cooperation, perhaps with non-traditional partners, is likely to be important to connect New Zealand to supplies of equipment and inputs. This might require a new paradigm for regional shipping, a stocktake of resources and capabilities across places like New Zealand, Australia, Indonesia, and the Philippines (all of which feature in that ‘top 8’ in our analysis of nuclear winter). Zeihan notes that there is ‘no obvious leader’ in Southeast Asia. This only underscores the potential value of a regional alliance for resilience.

Overall, an oil replacement, such as biofuels or hydrogen, will be critical to New Zealand’s plan if it seeks to preserve industrial society, along with the infrastructure to support it. Critical too will be regional alliances forged ahead of time with local resilience in mind. The transition to a society resilient to the shocks listed above might take decades but should be started now.

New Zealand has been identified in many writings on global catastrophe (including nuclear winter) as one of the few potentially sustainable corners of civilisation in the most extreme circumstances. These analyses include Zeihan’s book, where New Zealand features repeatedly (often as a functional dyad with Australia), and in our analyses on island refuges against extreme pandemics and against abrupt sunlight reducing scenarios such as nuclear winter (academic paper forthcoming, blog here). However, we have been clear that of the islands identified as ‘most prepared’, none are yet close to being ‘fully prepared’ for this suite of catastrophic risks.

New Zealanders must ask, if appropriate anticipation does not occur here, where chances are best, then where?  

Moving Forward

Many New Zealand organisations have started work on aspects of trade disruption, supply chain issues, or the future of agriculture and food. However, I would like to see the scenarios that are contemplated expanded to encompass the more severe catastrophes mentioned above, with at least some resilience work targeting such possibilities (which in turn should also help allay fears over the lesser challenges). A programme of work on global catastrophic and existential risks should complement and integrate with emerging and ongoing work on day-to-day risks to foster a resilient New Zealand across the decades to come.

The first step in such a resilience project is to understand the key common consequences across these scenarios. An obvious common impact is the loss of trade (which may occur in isolation or in a context of climate (nuclear winter) and/or electrical (EMP, solar flare) disruption, or other factors).

We will soon be announcing a project investigating exactly these issues, for which we have recently secured funding.

I am very keen to talk with anyone who has an interest in contributing to the project goal of mapping out what could be the nucleus of a New Zealand (nuclear, trade isolation, biothreat, supervolcano, solar flare, asteroid impact…) National Resilience Strategy and Plan. I am excited for upcoming wide engagement and hope to foster a sense of collaboration. Feel free to get in touch and share your experience, ideas, and expertise with me.  

A successful strategy depends on exactly what the impacts are likely to be, and that should now be explored for the most catastrophic scenarios.

Global catastrophe and risk analysis: Podcast smorgasbord

Image: Dan Gold, Unsplash

This instalment of the Adapt Research Blog brings you a selection of Matt’s recent audio and video presentations.

These appeared in podcast, radio and conference format through April–June 2022.

  • Podcast by Radio New Zealand (13 May, 2022):
  • Do we really need to prepare for nuclear war? (23 min), Matt and Nick Wilson in conversation with Sharon Brettkelly – Covering: Nuclear winter, resilience, and the cross-cutting benefits of preparation. Further details in our blog on Sustained Resilience to mitigate catastrophic risk.

Cambridge Conference on Catastrophic Risk 2022

The CCCR 2022 was held as a hybrid in-person and online conference 19–21 April 2022.

Opened by Lord Martin Rees, the conference attracted researchers and policymakers with an interest in global catastrophic risks such as biological threats, artificial intelligence, nuclear war, volcanic eruption and food shortages. Attendees engaged with keynote speakers, panel discussions, workshops and 7 minute lightning talks.

The Conference Programme is available here.

Videos of each conference day are now available on YouTube:

Day 1, Day 2, Day 3

Adapt Research Ltd contributed to authoring two lightning talks. Matt Boyd of Adapt Research presented the second of these. Slides and video timestamps are available here:

Island Refuges (YouTube) – Professor Nick Wilson (7 min)

National Risk Assessments (YouTube) – Dr Matt Boyd (7 min)

Sustained Resilience: the impact of nuclear war on New Zealand and how to mitigate catastrophe

Dr Matt Boyd & Prof Nick Wilson*

Photo by Chad Peltola on Unsplash

Efforts to prevent nuclear war should be greatly intensified – but we must also consider what happens if prevention fails. NZ is often cited as somewhere most likely to preserve a thriving society through a nuclear aftermath. However, our society is a complex adaptive system heavily dependent on trade. Major perturbations triggered by nuclear war could shift the state of NZ society from one of flourishing to one of mere survival. We detail these risks of societal failure and conclude with a set of first steps NZ could take to strengthen its societal systems.

“I had a dream, which was not all a dream. / The bright sun was extinguish’d, and the stars / Did wander darkling in the eternal space” (Byron ‘Darkness’)

Byron penned what could be a striking vision of nuclear winter 129 years before the atomic age. Holed up in a Swiss mansion during the ‘year without a summer’ following the eruption of Mt Tambora, he composed ‘Darkness’ (1816) on a day in which ‘the fowls went to roost at noon’.

‘Darkness’ imagines the severe cascading calamities that might ensue if the sun were obscured, as following nuclear war. We detailed these potential climate impacts and the consequences for NZ food production in a recent blog post, Putin and the Bomb.

However, in his poem Byron envisions the cascading impacts sun-blocking might have on energy supply, communications, resources, ecology, social cohesion, and conflict. In 1987 the NZ Nuclear Impacts Study examined the potential for similar cascading impacts (Green, Cairns, & Wright, 1987). This study involved 300 industry experts, government officials, a public survey, and role plays with citizens. In 35 years, nothing remotely as sophisticated has been done to update the findings for the NZ context.

Contrary to common misconception, radiation is not a major risk to NZ in a Northern Hemisphere nuclear war. It is commonly assumed that far flung Southern Hemisphere islands like NZ may fare comparatively well. For example, existential risk scholar Toby Ord writes in The Precipice, “if we consider somewhere like NZ… It is hard to see why they wouldn’t make it through with most of their technology (and institutions) intact” (Ord, 2020).

In what follows we question Ord’s assumption, reiterate the salience of nuclear war as a global catastrophic risk, its far-reaching impacts on society and industry and what NZ might do to mitigate the threat, including reprising the work of the 1980s with up-to-date understandings.

Food supply

“the wildest brutes / Came tame and tremulous; and vipers crawl’d / And twin’d themselves among the multitude, / Hissing, but stingless—they were slain for food”

A typical human needs around 2,100 kcal of food energy per day to avoid losing weight. NZ produces something in the order of 9,500 kcal/capita/day (Schramski, Woodson, Steck, Munn, & Brown, 2019), and exports the majority of this food. Although modelling of severe nuclear winter reported in a preprint indicates NZ food production could fall 58% (Xia et al., 2021), New Zealanders should, in principle, be able to be fed. However, orderly production and distribution of this supply assumes that people understand there will be enough, that there is sufficient energy to maintain production and distribution, that crop substitutions are appropriate, that essential machinery does not irrevocably break down, that unforeseen cascading socio-ecological impacts do not wreak havoc and that the country is not likely to be overcome by refugees.


Covid-19 and the war in Ukraine has taught us that complex interdependent human systems are often fragile – and trade can be vulnerable. Even, when just one ship blocked the Suez Canal, there were global trade disruptions. In a severe nuclear (or volcanic, or asteroid) winter key infrastructure in the Northern Hemisphere may lie in ruin, including ports, airports, fuel stores, fibre optic cables, satellites, factories, and data centres. Food production could collapse in breadbaskets such as the US and Ukraine. This would massively strain a world where two-thirds of countries are currently not food self-sufficient (Schramski et al., 2019). There may be hoarding, reluctance or inability to trade, severe food and fuel shortages, and ongoing conflict.

Research on volcanic eruptions at global ‘pinch points’ indicates that an unfortunately located eruption could disable world trade (Mani, Tzachor, & Cole, 2021). We must assume the same following dozens, scores, or even hundreds of nuclear detonations. Remote NZ may be on its own. At the very least Northern Hemisphere markets could be inaccessible and trade networks with Australia, Indonesia, the Philippines, Chile or Peru would need to be strengthened or forged.

Communications and governance

“And they did live by watchfires—and the thrones, / The palaces of crowned kings—the huts, / The habitations of all things which dwell, / Were burnt for beacons; cities were consum’d”

People will panic. This is natural. But actions hinge on information held. The nuclear impact study in NZ found that people were often mistaken, they thought radiation was the most important threat (46%) followed by cold weather (11%) (Green et al., 1987). This is probably not the case in NZ. Authorities must anticipate and provide clear, relevant information about nuclear winter, with two-way dialogue. We need a shared mental model that there should be enough food, but medicines and fuel might need to be rationed. At the beginning of the Covid-19 pandemic, communication in NZ was very successful, but eventually mis/dis-information crept in, the shared mental model was lost and tension arose.

However, in a nuclear aftermath standard communication by NZ authorities might not be possible. There could be widespread international internet and cloud outages, an electromagnetic pulse (EMP) targeted at Australia could potentially disable electronic equipment in NZ (Green et al., 1987), and over time NZ’s telecommunications infrastructure will likely degrade as parts break down and replacements are not available.

Energy and transport

“Forests were set on fire—but hour by hour / They fell and faded—and the crackling trunks / Extinguish’d with a crash—and all was black”

When considering total generic units of energy, NZ superficially appears self-sufficient (IEA 2021). However, NZ exports low-grade coal but imports refined oil; produces hydroelectric power, but this is partly configured to supply to an aluminium smelter; there is geothermal energy but a small electric vehicle fleet; and a single point of failure (one cable) spans the interisland strait. The system may not be resilient to major shocks. Without trade there would be extreme fuel shortages, compounded as the only oil ‘refinery’ has just shut its refining business. Overseas reserves would be useless without the ability to retrieve them. Even if refining were restored, a single key fault could cripple it again without imported parts and international expertise. The effects of an EMP could make the energy situation worse. Critically, energy is needed for food processing and distribution. Milk needs to be transported every day, without electric trucks this requires refined fuel. The energy system will degrade over time and beyond a certain threshold there could be catastrophic cascading effects throughout every other system.

Conflict and Refugees

“And War, which for a moment was no more, / Did glut himself again… / …The crowd was famish’d by degrees; but two / Of an enormous city did survive, / And they were enemies”

Internal conflict may arise if there are concerns about ongoing supply of food or energy, or if inequality is perceived. People seeking escape from war and famine may try to arrive by force, or bring novel infectious diseases (eg, if bioweapons are released in a Northern Hemisphere conflict). Although NZ is sheltered by a huge natural moat, the country must plan for the possibilities of such challenges. We need to calculate how many can be fed. En masse arrivals may be unlikely in a world without commercial transportation, but NZ’s vulnerability might require alliances with other survivors such as Australia, Indonesia, or Chile.

Ecology and flourishing

“The rivers, lakes and ocean all stood still, / And nothing stirr’d within their silent depths”

Ecological systems are complex adaptive systems with many interacting parts. Models of the impact of nuclear winter cannot account for all variables, and we know that ecological systems sometimes exhibit sudden and unpredictable shifts in state. Algal blooms or tropical storms exemplify these processes. It is possible that severe climate impacts of nuclear winter might disrupt global ecology for decades or forever. Human societies are part of this complex adaptive system (Walker & Salt, 2006). We must understand that as human systems degrade accumulating stresses across a range of tightly coupled and interdependent sectors can manifest as cascading failures (Homer-Dixon et al., 2015). As one of the havens most likely to survive comparatively intact after a nuclear war, NZ must avoid tipping into pre-digital, pre-industrial, or pre-agricultural states. Persisting institutions and technological systems will be needed to help ‘reboot’ a flourishing humanity across the years and decades after a catastrophic nuclear winter.

A possible solution for NZ?

NZ may have some inbuilt cultural resilience especially in Māori and Pasifika communities. Communitarian efforts via marae and other social networks have successfully distributed food and information in the past, such as during the Covid-19 pandemic and Kaikoura earthquake. NZ’s ‘social cohesion’ score is very high. But we can’t take this for granted in an information environment where risks are classified, and misinformation is rife.

Unfortunately, nuclear war matters because it is not improbable. Nuclear safety depends on a system of rational actors, perfect information, and fail proof systems that operate without error in perpetuity. The risk of nuclear war lies in human error, component failures, violent catalysis, irrational leaders, accident, miscalculation, and cyber vulnerabilities (see Nuclear Threat Initiative president Joan Rohlfing’s interview from 24 Feb here).

Nuclear winter especially matters because there is still a small possibility that it could lead to human extinction, not directly, but via cascading effects on food, energy, transport, trade, disease, and conflict. Study of these cascading interdependencies is very neglected.

NZ has a chance to both survive and sustain a thriving hub of complexity through nuclear winter. With promising baseline conditions, there is an argument NZ has an obligation to humanity to maximise its chances. This could be achieved by undertaking the following:

  • Repeat the 1987 Nuclear Impacts Study in today’s context and prioritise intervention according to experts, science and modelling (see Green et al. 1987 for initial policy suggestions).
  • Make a detailed local study of food production and distribution under nuclear winter and zero trade/scarce fuel conditions, as well as manage marine stocks to ensure surplus in times of need.
  • Research and prepare communication materials and plans, with redundancies, collaborate with the public and generate a shared mental model.
  • Incentivise distributed renewable energy sources, electric vehicle uptake, cycle infrastructure, home insulation, and reduce oil dependence, while maintaining refining capability until zero-oil reached.
  • Conduct simulations/walk-throughs of critical functions such as restoring systems after an EMP, or storing, rationing, and distributing food, fuel, medicines.
  • Reduce reliance on Northern Hemisphere export markets by diversifying regionally – particularly with Australia, the Pacific and Southeast Asia.
  • Study the potential irreplaceable failure points of NZ industry and crowdsource solutions and workarounds, eg, 3D printing.
  • Model the co-benefits of resilience measures against nuclear winter on climate targets, inequality, health, the economy.
  • Include nuclear war, nuclear winter, and NZ trade isolation in national risk assessments and make public NZ’s national risk register (the contents of which are currently classified).
  • Establish a Parliamentary Commissioner for Extreme Risks to provide resource, responsibility and political neutrality for assessing and governing nuclear risks and other extreme risks. We have previously made this case (Boyd & Wilson, 2021).
  • Research actions NZ might take to increase the chance of rebooting a collapsed global civilization, such as developing local digital manufacturing, renewable energy, and other independent high-tech sectors.


If nuclear war led the world to a collapsed, even pre-industrial state, all the gains in healthcare, life-expectancy, social institutions, and other domains of human endeavour attained in the last 200 years would be at risk. There is no guarantee they would be quickly recovered, and could even be lost forever.

At present nuclear war and winter impacts are much neglected (the word ‘nuclear’ did not appear in the ‘Summary of Public Consultation’ for NZ’s National Security Long-term Insights Briefing 2022). Also, when these type of impacts are examined internationally, there seems to be too much focus on just the climate and food impacts, as opposed to issues such as systems interdependencies, governance and communication. There are knowledge gaps about the dynamic cascading effects of nuclear war. It is inconceivable that any present government could successfully manage this kind of situation. We must build better systems that reduce inherent risks of nuclear war eg, better diplomacy and technical safeguards. Better yet, we should greatly intensify efforts to eliminate nuclear weapons. Until that day, we should nurture the changing mindset around climate change and expand this to all catastrophic risks, so we can anticipate them and be better ancestors.

Risk communication is critical. Citizens need to understand risks and have some concept that solutions are possible. This will encourage cooperation and coordination rather than conflict and degradation of social cohesion. No solution to a major risk will succeed without some degree of social cohesion. This is why the problem of mis/dis-information must be solved in parallel with work on catastrophic risks. No risks, nuclear or otherwise, exist in isolation and many of the measures we suggest above have wide-ranging co-benefits.

* Author details: Dr Boyd is a catastrophic risk researcher and Director of Adapt Research Ltd. He has funding support for work on this topic from the Centre for Effective Altruism’s Long-Term Future Fund. Prof Wilson is with the Department of Public Health, University of Otago, Wellington. Views are the authors’ own.

To enable more content on these topics, please consider donating below the References list.


Boyd, M., & Wilson, N. (2021). Anticipatory Governance for Preventing and Mitigating Catastrophic and Existential Risks. Policy Quarterly, 17(4), 20–31. doi:10.26686/pq.v17i4.7313

Green, W., Cairns, T., & Wright, J. (1987). New Zealand After Nuclear War. Wellington: New Zealand Planning Council.

Homer-Dixon, T., Walker, B., Biggs, R., CrÈpin, A.-S., Folke, C., Lambin, E. F., . . . Troell, M. (2015). Synchronous failure: the emerging causal architecture of global crisis. Ecology and Society, 20(3), 6. doi:10.5751/ES-07681-200306

Mani, L., Tzachor, A., & Cole, P. (2021). Global catastrophic risk from lower magnitude volcanic eruptions. Nature Communications, 12(1), 4756. doi:10.1038/s41467-021-25021-8

Ord, T. (2020). The Precipice: Existential Risk and the Future of Humanity. London: Bloomsbury.

Schramski, J. R., Woodson, C. B., Steck, G., Munn, D., & Brown, J. H. (2019). Declining Country-Level Food Self-Sufficiency Suggests Future Food Insecurities. BioPhysical Economics and Resource Quality, 4(3), 12. doi:10.1007/s41247-019-0060-0

Walker, B., & Salt, D. (2006). Resilience Thinking: Sustaining Ecosystems and People in a Changing World. Washington, DC: Island Press.

Xia, L., Robock, A., Scherrer, K. J. N., Harrison, C., Jaegermeyr, J., Bardeen, C., . . . Heneghan, R. F. (2021). Global Famine after Nuclear War. Research Square – Preprint. doi:10.21203/


Make a one-time donation

Make a monthly donation

Make a yearly donation

Choose an amount


Or enter a custom amount


Your contribution is appreciated.

Your contribution is appreciated.

Your contribution is appreciated.

DonateDonate monthlyDonate yearly

Putin and the Bomb: Why New Zealand national risk assessments should include planning for the potential impacts of nuclear winter

(9 min read)

Dr Matt Boyd & Prof Nick Wilson

Photo by Colin Watts on Unsplash

In this blog we briefly review the literature on the probability of nuclear war and what various models estimate to be the potential global climate impacts (eg, of nuclear winter). Although New Zealand is relatively well placed as a major food producer – a range of mitigation strategies could increase the probability of sustaining food security during a recovery period. To get the ball rolling the Government needs to perform a national risk assessment on this topic and commission work on identifying the most cost-effective preparations.

Putin’s Ukraine invasion and nuclear weapons

Does Russian President Vladimir Putin intend to use nuclear weapons, under what circumstances, and what would be the impact of such aggression?

This question is important because days after Russia’s invasion of Ukraine began in February 2022, Putin ordered Russia’s nuclear forces to high alert. It is also important because of the potentially dire consequences following a nuclear war, given that Russia possesses approximately 4500 nuclear warheads, not counting ‘retired’ weapons.

Below, we address the probability of nuclear war, the modelling work around its potential consequences, and some mitigation strategies that could minimise the impact of nuclear war on New Zealand.

How likely is nuclear war?

Since 1945 when nuclear weapons were used to end The Second World War, none have been used in combat. Unlike many natural phenomena there is no frequency distribution to base probability estimates upon. However, subjective estimates have been published.

In 2008 Hellman estimated the probability of full-scale nuclear war between the US and Russia in any given year at 0.02–0.5% (Hellman, 2008), however this calculation included a 6% annual probability of an ‘initiating event’ that could lead (with 33% probability) to a ‘Cuban missile crisis type’ event. If we follow Hellman’s assessment and consider Putin’s move to nuclear high alert in the context of the Ukraine invasion to be an ‘initiating event’, then the annualised probability of ‘a nuclear weapon being detonated’ rises to 3.3–16.5% and that of nuclear war to 0.3–8.3% (or higher if Putin’s Ukraine posture is considered an actual Cuban crisis-type event).

In 2013, Barrett et al estimated the annualised probability of inadvertent US-Russia nuclear war at 2% (90% CI, 0.02–7%) or 1% (0.001–5%) if it is assumed launch could not occur during ‘calm’ geopolitical periods (Barrett, Baum, & Hostetler, 2013). Half of the total risk was contained in periods of US-Russia tensions (perhaps the Ukraine war for example), but importantly this means the other half of the risk lies in peacetime. This is due to risks such as systems faults, miscalculations, malice, and third-party interference.

Several, other assessments put the probability in a similar range. However, these assessments usually focus on one possible scenario (eg, US-Russia war, inadvertent war, regional war between Pakistan and India, etc) and so the true probability of any kind of nuclear war between any nuclear armed nations will necessarily be higher. Baum et al have elaborated a full model (see p.21) for the factors which must be included to deduce the total probability of nuclear war (S Baum, de Neufville, & Barrett, 2018). However, multiple war games have concluded that Putin would probably use a nuclear weapon if he felt his regime was threatened (Civvis, 2022).

The crowd forecasting organisation Good Judgment has reported the estimated number of nuclear weapons detonated conditional on a nuclear weapon being used. Results were: 84% probability of 1–9 weapons detonating, 13% to 10–99, 2% to 100–999, and 1% to 1000 or more (Beard, Rowe, & Fox, 2020).

So, the risk of nuclear war is generally considered to be low in any given year, but certainly not trivial, and it may be elevated to the concerning level of several percent per annum in times of crisis. This makes the annual risk of nuclear war in times of US-Russia tensions possibly greater than the risk of a Covid-19-like pandemic, which has an estimated return time of 59 years (Marani, Katul, Pan, & Parolari, 2021).

Models suggest nuclear war would have significant climate impacts

Nuclear war would have impacts that reach far beyond the mass deaths and destruction from blast, thermal and radiation impacts from the bombs themselves at explosion sites. Baum and Barrett systematically collated these impacts in a model of nuclear war (S Baum & Barrett, 2018). The impacts include: ‘fire, blocked sunlight, damage to infrastructure, water supply disruption, agriculture disruption, food insecurity, healthcare disruption, infectious disease, transportation disruption, transportation systems disruption, energy supply disruption, satellite disruption, telecommunications disruption, shifted norms, and general malfunction of society’.

Since the 1980s it has been supposed that the greatest of these wider impacts would result from climate disruption. Nuclear firestorms would burn combustible material in cities and loft black carbon (soot) far into the stratosphere, where it would spread globally, and could persist for years imposing a global ‘nuclear winter’.

A regional nuclear war (such as between India and Pakistan where up to 100 bombs are used) might loft up to 5 teragrams (Tg) of soot, whereas a full-scale global war (eg, between the US and Russia where hundreds to thousands of weapons are exploded) might push as much as 150 Tg of soot into the stratosphere.

Modelling the effects of this in the 1980s relied on computing capacity that did not allow models to ‘look’ beyond the very short term or perform numerous model runs. However, in 2007 Robock et al modelled nuclear climate impacts with a, then, modern climate model, NASA’s ModelE. They found that 5 Tg, 50 Tg and 150 Tg scenarios would have significant climate impacts with severe reductions in surface temperature, precipitation and solar radiation (Robock, Oman, & Stenchikov, 2007; A. Robock et al., 2007). The climate changes were predicted to be large and long-lasting. At the lower end of the spectrum the impact might be similar to the impact from the worst volcanic climate impacts in recorded history, for example the civilisation altering impact of the Late Antiquity Little Ice Age (536–556CE) and at the upper end (150 Tg) could impose a ‘nuclear winter’ which might see summer time temperatures in the northern hemisphere 20–30 degrees C below normal, with an 8–9 degree C drop in mean global temperature spanning a decade. The 150 Tg case is very much a worst case scenario given that it assumes the use of almost the entire global nuclear arsenals, which is probably unrealistic given that many reserve warheads would need to be mobilised and deployed.

More recent modelling of both the regional nuclear war scenario (Reisner et al., 2018; Wagman, Lundquist, Tang, Glascoe, & Bader, 2020), and the global scenario (Coupe, Bardeen, Robock, & Toon, 2020), using more sophisticated climate models such as the WACCM, generally concur with these earlier estimates. Nevertheless, the regional war case might produce lesser impacts than previously thought, yet still have an impact on global agriculture and food trade ‘unmatched in modern history’ (Jagermeyr et al., 2020). Even so, the potential impacts are still highly uncertain and depend on the behaviour of the relevant fires and the material that is available to be burned, which in turn depends on where the weapons are targeted.

What is generally agreed is that the worst-case scenarios would devastate ordinary global agriculture. Results of global modelling of 150 Tg scenarios, currently available as a preprint (Xia et al., 2021), suggest yield losses for major food crops (maize, rice, soybean and spring wheat) and marine fish, averaged over the first five years, might hit 79% loss globally and approach 100% loss in the northern hemisphere, (see also Jagermeyr et al 2020 for related peer-reviewed estimates pertaining to regional war). The impact on global food trade would be disastrous and billions of people would be at risk of starvation.  

Additionally, ozone could be catastrophically depleted by stratosphere heating and the UV index at the Earth’s surface could rise to 35–45, or more, in places for several years (yes, this is the index reported by weather forecasters where 11+ is considered ‘severe’). The impact of this on global agriculture is unknown (Bardeen et al., 2021), but could be important.

Despite these catastrophic impacts, these models suggest that some places might be comparatively unscathed. This is because regions between the equator and 30 degrees south are not likely to be as impacted by climate changes. Although the equatorial monsoons may be greatly diminished, the growing seasons in some regions of Africa and South America may persist (Coupe et al., 2020). Additionally, remote southern hemisphere islands like New Zealand and Australia appear in the models to suffer less severe temperature drops (Coupe et al., 2020; A Robock et al., 2007), and some regions such as the Caribbean might even see increased fish catch (Scherrer et al., 2020).

What could be done to mitigate nuclear winter in New Zealand?

As with pandemics, prevention of nuclear war would be vastly better than being forced to respond. Immense diplomatic efforts are needed to resolve the situation in Ukraine. However, just as the world ought to be planning to mitigate the impacts of the next pandemic, we ought to address the potential impacts of nuclear war. In particular, policy should address food insecurity. This can be done by striking the right mix between the following three strategies (S. Baum, Denkenberger, Pearce, Robock, & Winkler, 2015):

  • Food stockpiles (which while expensive can allow for transition to a new normal in the event)
  • Agricultural adaptation including winter hardy crops
  • Development of alternative resilient food systems which do not depend on normal levels of sunlight

New Zealand specifically is a vast food overproducer due to its export economy. In a context where global food trade is severely disrupted, New Zealand could retain for domestic use food that is normally exported. Indeed, current volumes of dairy exports alone would be able to supply more than all the dietary energy needs of the whole New Zealand population (calculations by the authors – available on request). However, normal agricultural yields are likely to be diminished after a nuclear war. The calculations by Xia et al suggest that New Zealand might suffer reduced production of major crops of approximately 60% in worst scenarios (Xia et al., 2021). Applied to grass yield, along with the absence of palm kernel extract imports, this would severely impact dairy production. We note that Xia et al’s estimates are extrapolated from crude global macro-indicators and more detailed regional studies should be performed.

Production and distribution might additionally be hampered by lack of fossil fuel and fertiliser imports, and other impacts on machinery and access to parts. In cases where exports are retained for local consumption, there would need to be a plan in place to redistribute the food locally.

But with appropriate foresight, much agricultural production could continue with domestic production of biodiesel for farm machinery (or greater use of electric vehicles on farms), and increased local production capacity of fertiliser. The expansion of household and community gardens could be promoted by both central and local governments. These could focus on such highly efficient crops such as potatoes, but also crops that tolerate lower sunlight levels eg, winter vegetables. Also, the stock of marine food could be managed pre-war to maximise reserves and therefore yield if fishing is ramped up in the near-term aftermath of a nuclear war (Scherrer 2020).

Photo by Paul Einerhand on Unsplash

New Zealand could also invest in research and development of alternative foods such as ocean greens (eg, farming seaweed), single-celled protein (García Martínez et al., 2021), synthetic fat (García Martínez, Alvarado, & Denkenberger, 2022), as well as the role of cheap polymer film greenhouses which could be rapidly scaled up in the months after nuclear war (Alvarado et al 2020) – especially if planning for more severe nuclear winter impacts was thought to be worthwhile.

Additional research on nuclear winter is needed

Some government-funded NZ work on the impact of nuclear war was done in the 1980s by the NZ Planning Council (eg Preddey, Wilkins, Wilson, Kjellstrom, & Williamson, 1982; Green et al. 1987). But, as far as we are aware little has been done since then. It is currently unclear whether nuclear winter is contemplated in the country’s National Risk Register, given that the contents of this document is classified. We discovered in February 2020 that New Zealand was very unprepared for a Covid-19-type pandemic. We don’t want to discover that we are just as unprepared for a nuclear winter if it happens.

We have previously argued for transparency around the national risk assessment process, wider consultation and a publicly accessible national risk register, along with the appointment of a Parliamentary Commissioner for Extreme Risks to oversee analysis and planning across a portfolio of risks (Boyd & Wilson, 2021).

These issues around nuclear winter should also be raised at the United Nations (UN), as we have argued before (Boyd & Wilson, 2020), and as would be consistent with the recent UN framework for ‘risk informed sustainable development’ (UNDRR, 2021).

The Royal Society of New Zealand and/or the Department of the Prime Minister and Cabinet (DPMC), should consider doing an updated report on the impacts and responses to nuclear war and nuclear winter, including what the government and citizens might consider doing in anticipation. Engagement with iwi and key New Zealand agricultural and fisheries organisations would be important to shift the perspective on New Zealand’s food supply towards one of long-term resilience ‘no matter what’, beyond anticipated greenhouse gas climate change, by thinking about severe cooling episodes too. These ‘winters’ could be produced not just by nuclear war, but by major volcanic events as well. The eruption of Mt Tambora in 1815 produced 53-58 Tg of SO2 and produced global winter-like effects (it was the ‘year without a summer’). The eruption in January 2022 of Hunga Tonga-Hunga Ha’apai puts this in perspective as it produced only 0.4 Tg.

In summary, the available literature suggests that the risk of nuclear war is far from trivial and is likely to be increased at times of international crisis. Various models have estimated that the potential global climate impacts (eg, of nuclear winter) could be severe – though less so for islands in the southern hemisphere such as New Zealand. Although New Zealand is relatively well placed as a major food producer – a range of mitigation strategies could increase the probability of sustaining food security during a recovery period. To get the ball rolling the Government needs to perform a national risk assessment on this topic and commission work on identifying the most cost-effective preparations.


Bardeen, C. G., Kinnison, D. E., Toon, O. B., Mills, M. J., Vitt, F., Xia, L., . . . Robock, A. (2021). Extreme Ozone Loss Following Nuclear War Results in Enhanced Surface Ultraviolet Radiation. Journal of Geophysical Research: Atmospheres, 126(18), e2021JD035079. doi:10.1029/2021JD035079.

Barrett, A., Baum, S., & Hostetler, K. (2013). Analyzing and Reducing the Risks of Inadvertent Nuclear War Between the United States and Russia. Science and Global Security, 21(2), 106–133.

Baum, S., & Barrett, A. (2018). A Model for the Impacts of Nuclear War: Global Catastrophic Risk Institute Working Paper 18-2. Retrieved from

Baum, S., de Neufville, R., & Barrett, A. (2018). A Model For The Probability Of Nuclear War: Global Catastrophic Risk Institute Working Paper 18-1. Retrieved from

Baum, S., Denkenberger, D. C., Pearce, J. M., Robock, A., & Winkler, R. (2015). Resilience to global food supply catastrophes. Environment Systems and Decisions, 35(2), 301–313. doi:10.1007/s10669-015-9549-2.

Beard, S., Rowe, T., & Fox, J. (2020). An analysis and evaluation of methods currently used to quantify the likelihood of existential hazards. Futures, 115, 102469. doi:10.1016/j.futures.2019.102469.

Boyd, M., & Wilson, N. (2020). Existential Risks to Humanity Should Concern International Policymakers and More Could Be Done in Considering Them at the International Governance Level. Risk Analysis, 40(11), 2303–2312. doi:10.1111/risa.13566.

Boyd, M., & Wilson, N. (2021). Aotearoa New Zealand would benefit from anticipatory central governance for preventing and mitigating catastrophic and existential risks. Policy Quarterly, 17(4), 20–31. doi:10.26686/pq.v17i4.7313.

Civvis, C. (2022). How does this end? . Retrieved from

Coupe, J., Bardeen, C., Robock, A., & Toon, O. (2020). Nuclear Winter Responses to Nuclear War Between the United States and Russia in the Whole Atmosphere Community Climate Model Version 4 and the Goddard Institute for Space Studies ModelE. Journal of Geophysical Research: Atmospheres, 124(15), 8522–8543. doi:10.1029/2019JD030509.

García Martínez, J. B., Alvarado, K. A., & Denkenberger, D. C. (2022). Synthetic fat from petroleum as a resilient food for global catastrophes: Preliminary techno-economic assessment and technology roadmap. Chemical Engineering Research and Design, 177, 255–272. doi:10.1016/j.cherd.2021.10.017.

García Martínez, J. B., Egbejimba, J., Throup, J., Matassa, S., Pearce, J. M., & Denkenberger, D. C. (2021). Potential of microbial protein from hydrogen for preventing mass starvation in catastrophic scenarios. Sustainable Production and Consumption, 25, 234–247. doi:10.1016/j.spc.2020.08.011.

Green, W., Cairns, T. and Wright, J. (1987). New Zealand After Nuclear War. New Zealand Planning Council, Wellington.

Hellman, M. (2008). Risk analysis of nuclear deterrence. The Bent of Tau Beta Pi, 99(2), 14.

Jagermeyr, J., Robock, A., Elliott, J., Muller, C., Xia, L., Khabarov, N., . . . Schmid, E. (2020). A regional nuclear conflict would compromise global food security. Proceedings of the National Academy of Sciences, 117(13), 7071–7081. doi:10.1073/pnas.1919049117.

Marani, M., Katul, G. G., Pan, W. K., & Parolari, A. J. (2021). Intensity and frequency of extreme novel epidemics. Proceedings of the National Academy of Sciences, 118(35), e2105482118. doi:10.1073/pnas.2105482118.

Preddey, G., Wilkins, P., Wilson, N., Kjellstrom, T., & Williamson, B. (1982). Nuclear Disaster: A Report to the Commission for the Future. Retrieved from

Reisner, J., D’Angelo, G., Koo, E., Even, W., Hecht, M., Hunke, E., . . . Cooley, J. (2018). Climate Impact of a Regional Nuclear Weapons Exchange: An Improved Assessment Based On Detailed Source Calculations. Journal of Geophysical Research: Atmospheres, 123(5), 2752-2772. doi:10.1002/2017JD027331.

Robock, A., Oman, L., & Stenchikov, G. L. (2007). Nuclear winter revisited with a modern climate model and current nuclear arsenals: Still catastrophic consequences. Journal of Geophysical Research: Atmospheres, 112(D13). doi:10.1029/2006JD008235.

Robock, A., Oman, L., Stenchikov, G. L., Toon, O. B., Bardeen, C., & Turco, R. P. (2007). Climatic consequences of regional nuclear conflicts. Atmos. Chem. Phys., 7(8), 2003–12. doi:10.5194/acp-7-2003-2007.

Scherrer, K. J. N., Harrison, C. S., Heneghan, R. F., Galbraith, E., Bardeen, C. G., Coupe, J., . . . Xia, L. (2020). Marine wild-capture fisheries after nuclear war. Proceedings of the National Academy of Sciences, 117(47), 29748–29758. doi:10.1073/pnas.2008256117.

UNDRR. (2021). A Framework for Global Science in Support of Risk-informed Sustainable Development and Planetary Health. Retrieved from

Wagman, B. M., Lundquist, K. A., Tang, Q., Glascoe, L. G., & Bader, D. C. (2020). Examining the Climate Effects of a Regional Nuclear Weapons Exchange Using a Multiscale Atmospheric Modeling Approach. Journal of Geophysical Research: Atmospheres, 125(24), e2020JD033056. doi:10.1029/2020JD033056.

Xia, L., Robock, A., Scherrer, K. J. N., Harrison, C., Jaegermeyr, J., Bardeen, C., . . . Heneghan, R. F. (2021). Global Famine after Nuclear War. Research Square – Preprint. doi:10.21203/

%d bloggers like this: