The shape of impacts to come: lessons and opportunities for adaptation from uneven increases in global and regional temperatures

Uneven patterns in the rate of climate change have profound implications for adaptation. Assuming a linear or monotonic increase in global or regional temperatures can lead to inefficient planning processes that underestimate the magnitude, pattern, and timing of the risks faced by human and natural systems, which could exaggerate future impacts and the costs of managing them. Adaptation planning needs to move beyond imposing linear thinking and analysis onto nonlinear systems. Doing so would improve research into adaptive management processes that learn from and adapt to new knowledge at a pace that reflects non-linearity. Specifically, the pace of adaptation must consider the potential consequences of uneven increases in weather and climate variables as a means to reduce system vulnerability. Projections simulating periods of relative stability with those of rapid change would lead to more complex and more accurate expectations of future risks and associated consequences for human and natural systems. Adaptation planning based on such projections could then consider the implications of non-linear climate change on the extent of any adaptation effort, including quantified (or qualitative) risks and associated costs and benefits. Adaptation planning could be improved by projections that incorporate more nuanced understandings of how development processes could interact with climate change to alter future risks and vulnerabilities. Two examples are highlighted to illustrate the complexity and dynamic nature of non-monotonic climate-development-response scenarios: vector borne diseases and agricultural productivity.