When Stuart Kirk, HSBC’s Global Head of Responsible Investment, argued that climate risk wasn’t something investors should worry about, he made an important claim. He said: ‘Who cares if Miami is six metres below sea level? Amsterdam is six metres below sea level and a very nice place to be’. The point he was making was that societies will adapt to the impacts of climate change, learning to cope with hotter, drier, stormier weather and changing sea levels. While it is true that people and nature adjust to weather and climate variability, the question of adaptability to long-term and deep-seated changes in climate is an important one.
If there were an unlimited capacity to adapt, as Stuart Kirk suggests there may be, climate change would not be of great concern to any of us. But it seems likely that there are climates which would be difficult and perhaps even impossible to adapt to, however wealthy a society was. A concern about limits to adaptation is therefore central to our views about climate risk and what policy and market responses may be appropriate. The more we worry about our ability to adapt, the more we should worry about the impacts of climate change.
The problem is that we don’t know very much about our limits to adapt, how to identify them, how they may differ between places, or what we might do once we approach such adaptation limits, or tip over them. What if the people of Miami decided that they did not want to live behind sea dykes? What would their options be? Could they build sea barrages out in the ocean? Could they raise the level of the entire city? How much would it cost? Who would pay? Who would be the winners and who the losers? How would these changes be governed?
Although the problem of adaptation limits is widely accepted, it is complex and contested. Conventional economic analysis tends to assume high levels of adaptiveness to climate change and, as a result, delivers high ‘optimal’ global warming targets, in the range +3-4˚C . This is way beyond international political targets, such as those set out in the 2015 Paris Agreement which aims to limit global warming to between +1.5-2˚C. Alternative economic analysis, including the 2006 Stern Review, suggests that limits to the capacity to adapt, especially to low-probability but potentially catastrophic impacts, lie at the heart of debates in climate economics and policy
As the most recent report of the Intergovernmental Panel on Climate Change makes clear, there is accumulating evidence that adaption limits to climate-related risks are emerging in relation to several hazards (heat, flooding, fire, sea level rise) in different sectors and regions (coasts, water, food and agriculture, cities and settlements, critical infrastructures). For instance, homeowners around Lake Charles in Louisiana (United States) are already choosing to participate in a federal buyout programme to help them sell their properties and move away. Lake Charles Mayor, Nic Hunter said after repeated hurricane-induced flooding, “…eventually you do kind of get to the point where you ask Mother Nature: What more can you do to us?” Limits to adaptation are clearly a present-day reality in some places.
Climate risks are unevenly distributed – spatially, socially, temporally. As risks change and escalate due to climate change, so these uneven distributions of risk will tend to become entrenched, deepening existing inequalities. The capacity of the City of Miami to adapt to sea level rise is not the same as the capacity of the nation of Vanuatu to adjust. At local, national, and international scales, public policy responses to this unequal pattern of climate-related loss and damage will be expected. More positively, there are also opportunities to support transformative adaptation to achieve desired futures under climate change.
We urgently need to better understand our adaptation limits. One approach has defined a limit to adaptation as being a threshold beyond which, despite adaptive effort, valued objectives (like being able to live in a place and sustain a livelihood) can no longer be secured from intolerable climate-related risk.
There are perhaps four pressing dimensions for future research:
1. Understanding the social and biophysical dimensions of limits and how they interact
Understanding the factors underlying limits to adaptation is crucial. Vulnerability to climate risk and adaptation are complex outcomes of many factors, often context-specific . The physical risk of drought faced by farm businesses may differ markedly across England, as will their ability to invest in adaption, like irrigation. Limits are an outcome of situated social processes in which social actors have access to certain resources, capacities, and capabilities. But factors influencing adaptation limits are often structural, institutional, economic, and cultural. For instance, national regulations restricting water abstraction linked to nature conservation policy may constrain the ability to irrigate farmland.
2. Understanding the dynamics of adaptation limits
Adaptation to climate risk must occur over time and needs to overcome economic and institutional inertia. As climate change accelerates, adapting long-lived critical infrastructures may be costly and difficult. The transition to Net Zero carbon emissions needs to be consistent with the transition to climate-resilience. Adaptation gaps may emerge, leading to new risks.
Many climate risks stem from extreme events, including droughts, storms and floods. There are important questions about how social actors respond to infrequent, extreme events leading to losses. While some analysis assumes that adaptation decision-making is based on an analysis of risks, costs and benefits, some research suggests otherwise.
3. Developing an economic understanding of adaptation limits
As impacts of climate change expose economic activities to risk, effort and investment to reduce these risks will increase up to a limit, at which point something has to give (as at Lake Charles), with costs to individuals and businesses, but also for the economy as a whole. Recent research has developed granular global data for the link between climate and economic, social and health outcomes, while another study has focused for example on linking economic productivity to rainfall. Yet another study emphasises the importance of including adaptation into economic analysis of climate change. There is still much work to do here.
4. Addressing the justice issues linked to the uneven distribution of limits to adaptation.
We must also focus on the procedural and distributional consequences of adaptation limits and how to address them. Normative, political, and cultural considerations underlie all adaptive responses to climate change, as they shape what is valued and what adaptive options are viewed as appropriate. Likewise, prevailing norms and values will determine what are viewed as tolerable and intolerable risks requiring gradual or transformative adaptation. There is also potential for some adaptation strategies to transfer vulnerability to other places or groups.
Limits to adaptation, like many other expressions of climate change, are no longer just anticipated, but are increasingly observed. As those limits come into focus, some people will be able to find paths to reduce climate risks to tolerable levels, while others find themselves unable to escape significant damage and loss, precipitating radical changes, typically leading to serious losses in welfare, well-being and perhaps identity. We need a collective research effort to advance knowledge that is relevant for policymakers and practitioners as they plan and finance responses to climate change. If escalating loss and damage can no longer be avoided, even in a 1.5˚C world, there is a need for a mature and well-articulated knowledge base to inform the uncomfortable choices that lie ahead. Hoping for the best is not really an option.
Photo Credit: Toomas Tartes on Unsplash
About the author
Frans Berkhout is Professor of Environment, Society and Climate at King’s College London. He joined King’s in 2013 and was the Executive Dean of the Faculty of Social Science & Public Policy between 2015 and 2021.
He was previously Director of the Future Earth programme, based at the International Council for Science (ICSU) in Paris, and Director of the Institute for Environmental Studies (IVM) at the VU University Amsterdam in The Netherlands. Before that, he held posts at SPRU (Science and Technology Policy Research), University of Sussex, and was Director of the UK Economic and Social Research Council’s Global Environmental Change and Sustainable Technologies programmes. Frans was a lead author in the Intergovernmental Panel on Climate Change (IPCC)’s 4th and 5th Assessment Reports (2007 and 2014) and shared the 2007 Nobel Peace Prize as a member of the IPCC.