Past is prologue: A case study exploration of the role of climate indicators in adaptation in the United States

Climate change projections have been the primary informational currency for exploring the impacts of climate change and thus informing how to prepare for and adapt to those projected impacts. However, climate indicators, which we define as observed climate trends, conditions, and impacts often associated with socioeconomic consequences, can also be helpful in motivating or shaping adaptation actions. In this paper, we explore the use of climate indicators in adaptation decision-making through three detailed case studies. We find that climate indicators play an important and sometimes foundational role in the context setting and support building stages of the decision process. We also find that climate indicators sometimes play a role in the informing policy-decision stage. However, climate indicators play a limited and less explicit role in the implementing and evaluating policy stages of the decision process. Ultimately, an integrated approach that draws upon both climate indicators and climate projections to support adaptation decision-making is more productive than a narrow focus on climate projections alone.