Podcast Summary:

New Books Network
Episode: Susannah Fisher, "Sink or Swim: How the World Needs to Adapt to a Changing Climate" (Bloomsbury, 2025)
Host: Dr. Miranda Melcher
Guest: Dr. Susannah Fisher
Date: October 7, 2025

Episode Overview

In this episode, Dr. Miranda Melcher interviews Dr. Susannah Fisher about her new book Sink or Swim: How the World Needs to Adapt to a Changing Climate. The discussion centers on the urgent reality of climate change and, crucially, the world’s need to move beyond mitigation and accelerate adaptation efforts. Dr. Fisher draws from her extensive experience as a researcher and policy advisor, explaining systemic barriers, the complexity of adaptation, and the political, legal, and societal challenges ahead. The conversation uses clear examples—from food systems and migration to conflict, nature, and the role of militaries—to make an intricate subject approachable for listeners of all backgrounds.

Key Discussion Points and Insights

1. Motivation for Writing the Book

• [03:11] Dr. Susannah Fisher introduces herself as a researcher at UCL with a decade’s experience in climate adaptation, both practically (with governments and international organizations) and academically.
  • “I've really started to feel that we're just not going far or fast enough on adaptation, but also that there are really big questions that adaptation and climate impact pose for how we live our lives that just aren't really on the public consciousness.” (Dr. Susannah Fisher, 03:19)
• The book aims to surface “the really big questions and hard choices about how we can adapt to climate change” in an accessible way.

2. Scope: Systems Affected by Climate Change

• [04:33] Climate change's primary and secondary effects are vast and interconnected:
  • Extreme heat, storms, droughts, floods, rising sea levels
  • Indirect effects on food production, disease travel, biodiversity, and more
• Fisher organizes adaptation challenges into four systems:
  • Mobility: Migration and ability to move within and across borders
  • Nature/Biodiversity: Relationships between adaptation and ecosystems
  • Food: Production, transport, storage, and trade under new climate realities
  • Conflict: Inter- and intra-country tensions linked to climate impacts
• “I thought those four topic areas were really some of the areas where I saw the biggest political and most challenging and fractious questions.” (Dr. Susannah Fisher, 05:59)

3. Measuring Successful Adaptation—Are We Doing Enough?

• [06:58] There is no straightforward metric; it’s about matching the scale of expected impacts with the adequacy of the response.
• Examples of adaptation measures: flood insurance, building regulations, and zoning laws.
• Acknowledges the concept of "limits to adaptation": some places will simply become unviable, regardless of investments.
  • “It's quite clear that not all places will be able to manage that way. And we'll get to what's called the limits, where it just won't be safe to live somewhere. However much you invest in adaptation or just the cost of investing will be much, much too high.” (Dr. Susannah Fisher, 07:41)
• The pace and scale of adaptation worldwide is not sufficient.

4. Major Barriers to Effective Adaptation

• [08:29]
  • Financial: Drastic shortfalls in adaptation funding, both internationally (via climate finance flows) and domestically.
    • UNEP's estimate: need $100–350 billion/year; reality is far less.
  • Political and Institutional: Perverse incentives, lack of integration with powerful policy areas (e.g., finance/treasury), adaptation's low political profile.
  • Public Engagement: Limited participation in planning, which leads to resistance or ineffectiveness.
    • “...decisions can often also end up being quite disconnected from how people live their lives.” (Dr. Susannah Fisher, 10:20)
  • Not just a money problem—systemic political and social change needed to realign incentives.

5. Climate-Driven Migration and Legal Hurdles

• [11:50]
  • Climate-driven mobility is controversial and difficult to distinguish from other migration drivers.
  • Legal gap: No international legal category for cross-border “climate migrants”—most movement remains internal.
    • “...there is no legal provision for people to move across national borders because of climate change.” (Dr. Susannah Fisher, 12:26)
  • Lack of social protection for climate migrants.

6. Food Systems: Complexity, Stakeholders, and Resilience

• [13:53]
  • Adapting food systems requires more than changing what’s grown where—it involves trading relationships, access, storage, and multi-stakeholder cooperation.
  • Interplay of public regulation and private sector dominance (few corporations control staple crop flows).
  • Efficiency vs. resilience: need to incentivize diversity and redundancy in supply chains, moving away from just-in-time models.
    • “The whole system is very complex and there isn't necessarily just one lever that we can pull to make the change that we need.” (Dr. Susannah Fisher, 15:49)
  • Calls for a “systemic approach”—blending regulation, incentives, and new trading rules for resilience.

7. Nature: Assisted Migration, Challenges, and Ethical Questions

• [18:01]
  • Moving species for their survival raises ecological, logistical, and moral dilemmas.
    • Risks include invasive species, public opposition, and prioritization (“photogenic” vs. keystone species).
  • Existing actions: animal corridors, climate refuges, some cases of intentional relocation.
    • “But it is fraught with difficulty because you're moving something, one species into an ecosystem that already exists and you might upset a very delicate web of relationships.” (Dr. Susannah Fisher, 19:14)

8. Climate Change and Conflict

• [20:39]
  • Impacts can drive violent conflict, political disputes, or local disagreements (e.g., between farmers and conservationists).
  • Rewilding and adaptation efforts can clash with established community practices and livelihoods.
  • Transboundary resources, notably water, are flashpoints (e.g., India-Pakistan's Indus river).
  • Urges proactive, flexible agreements to manage these evolving tensions.
    • “The important thing about climate, climate and conflict is thinking what agreements and relationships can we put in place to manage those changes before they happen?” (Dr. Susannah Fisher, 23:11)

9. The Role of the Military in Adaptation

• [24:46]
  • Militaries increasingly providing disaster relief; raises questions about mission, resources, and risks of politicization.
    • “...the military is actually becoming quite a default responder on adaptation.” (Dr. Susannah Fisher, 25:05)
  • Possibility of militaries being overstretched and the potential need for dedicated civil disaster response forces.

10. Pathways to Mobilization and Adaptation

• [27:05]
  • There is no “silver bullet.” Solutions must be context-specific and multifaceted.
  • Political action, social movements, and legal pressure are essential levers.
    • “I think adaptation has often not been a primary area for social movements to engage with. And I think that's maybe partly because it feels like giving in.” (Dr. Susannah Fisher, 28:01)
  • Litigation is rising as a tool to push for more aggressive action.
  • Calls for bold policy innovation and participatory processes (citizens’ assemblies, deliberative forums).

Notable Quotes and Memorable Moments

• On adaptation’s urgency:
  “It's quite clear that not all places will be able to manage that way. And we'll get to what's called the limits, where it just won't be safe to live somewhere. However much you invest in adaptation...” (Dr. Susannah Fisher, 07:41)

• On public engagement:
  “...decisions can often also end up being quite disconnected from how people live their lives. And so people might respond by resisting the plans, for example...” (Dr. Susannah Fisher, 10:20)

• On legal limbo for climate migrants:
  “...there is no legal provision for people to move across national borders because of climate change.” (Dr. Susannah Fisher, 12:26)

• On the challenge in food systems:
  “The whole system is very complex and there isn't necessarily just one lever that we can pull to make the change that we need.” (Dr. Susannah Fisher, 15:49)

• On moving animal species:
  “But it is fraught with difficulty because you're moving... one species into an ecosystem that already exists and you might upset a very delicate web of relationships...” (Dr. Susannah Fisher, 19:14)

• On conflict over adaptation:
  “The important thing about climate, climate and conflict is thinking what agreements and relationships can we put in place to manage those changes before they happen?” (Dr. Susannah Fisher, 23:11)

• On militaries in adaptation:
  “...the military is actually becoming quite a default responder on adaptation.” (Dr. Susannah Fisher, 25:05)

• On the need for systemic change:
  “There is no one silver bullet policy that's going to solve all of our issues. It's going to be a response to coastal relocation in the US and the UK, a response to wildfires in Greece and Spain.” (Dr. Susannah Fisher, 27:09)

• Call to action:
  “I really hope that people take it as a call to arms, to action, but that they don't feel overwhelmed by the scale of the challenge...” (Dr. Susannah Fisher, 31:06)

Key Segment Timestamps

• [03:11] – Dr. Fisher introduces her background and aims of the book
• [04:33] – Discussion of climate impacts and systems approach
• [06:58] – How to measure if adaptation is sufficient
• [08:29] – Barriers to effective adaptation (money, politics, engagement)
• [11:50] – Political and legal questions on migration
• [13:53] – Complexities in food system adaptation
• [18:01] – Moving species and adapting biodiversity
• [20:39] – Climate change as a driver of conflict
• [24:46] – The military’s evolving role in disaster response
• [27:05] – Pathways to organizing and mobilizing for adaptation
• [30:43] – What Dr. Fisher hopes readers take away from the book
• [32:15] – Dr. Fisher’s future projects and ongoing research

Conclusion: Themes and Takeaways

• Urgency and Scale: Climate adaptation must accelerate and expand in scale; current efforts are seriously insufficient.
• Systemic Approach: No single measure or institution can solve the problem; an integrated systems approach is essential.
• Complex Barriers: Financial, political, legal, and social challenges are deeply interwoven.
• Action and Hope: Change is possible—through activism, legal avenues, political reform, community engagement, and bold policy thinking. Dr. Fisher encourages listeners not to feel overwhelmed, but to see their own potential roles in driving forward adaptation, both locally and globally.

“We can take the next steps today and we can build on those steps and that's the way that we can work together to address these challenges.”
— Dr. Susannah Fisher (31:49)

For more detailed exploration and practical avenues for engagement, Dr. Fisher’s book, Sink or Swim: How the World Needs to Adapt to a Changing Climate, is now available from Bloomsbury.