U.S. Climate Resilience Toolkit

The Working Group II contribution to the IPCC Sixth Assessment Report assesses the impacts of climate change, looking at ecosystems, biodiversity, and human communities at global and regional levels. It also reviews vulnerabilities and the capacities and limits of the natural world and human societies to adapt to climate change.

Arctic ecosystems and communities are increasingly at risk due to continued warming and declining sea ice. The Arctic marine ecosystem and the communities that depend upon it continue to experience unprecedented changes as a result of warming air temperatures, declining sea ice, and warming waters. This 2019 update to the Arctic Report Card draws particular attention to the Bering Sea region, where declining winter sea ice exemplifies the potential for sudden and extreme change. Indigenous Elders from the Bering Sea region offer their experiences of living at the forefront of climate change.

The Global Change Research Act of 1990 mandates that the U.S. Global Change Research Program deliver a report to Congress and the President no less than every four years that “1) integrates, evaluates, and interprets the findings of the Program…; 2) analyzes the effects of global change on the natural environment, agriculture, energy production and use, land and water resources, transportation, human health and welfare, human social systems, and biological diversity; and 3) analyzes current trends in global change, both human-induced and natural, and projects major trends for the subsequent 25 to 100 years.” The Fourth National Climate Assessment (NCA4) fulfills that mandate in two volumes. This report, Volume II, draws on the foundational science described in Volume I, the Climate Science Special Report. Volume II focuses on the human welfare, societal, and environmental elements of climate change and variability for 10 regions and 18 national topics, with particular attention paid to observed and projected risks, impacts, consideration of risk reduction, and implications under different mitigation pathways. Where possible, NCA4 Volume II provides examples of actions underway in communities across the United States to reduce the risks associated with climate change, increase resilience, and improve livelihoods. This assessment was written to help inform decision makers, utility and natural resource managers, public health officials, emergency planners, and other stakeholders by providing a thorough examination of the effects of climate change on the United States.

As a key part of the Fourth National Climate Assessment (NCA4), the U.S. Global Change Research Program (USGCRP) oversaw the production of this stand-alone report of the state of science relating to climate change and its physical impacts. The Climate Science Special Report (CSSR) is designed to be an authoritative assessment of the science of climate change, with a focus on the United States, to serve as the foundation for efforts to assess climate-related risks and inform decision making about responses. 

As Volume 1 of NCA4, CSSR serves several purposes, including providing (1) an updated and detailed analysis of the findings of how climate change is affecting weather and climate across the United States; (2) an executive summary and 15 chapters that provide the basis for the discussion of climate science found in the second volume of NCA4; and (3) foundational information and projections for climate change, including extremes, to improve “end-to-end” consistency in sectoral, regional, and resilience analyses within the second volume. CSSR integrates and evaluates the findings on climate science and discusses the uncertainties associated with these findings. It analyzes current trends in climate change, both human-induced and natural, and projects major trends to the end of this century. As an assessment and analysis of the science, CSSR provides important input to the development of other parts of NCA4, and their primary focus on the human welfare, societal, economic and environmental elements of climate change. Much of the underlying report is written at a level more appropriate for a scientific audience, though the Executive Summary is intended to be accessible to a broader audience. 

This document provides final guidance for federal agencies on how to consider the impacts of their actions on global climate change in their National Environmental Policy Act (NEPA) reviews, providing a framework for agencies to consider both the effects of a proposed action on climate change, as indicated by its estimated greenhouse gas emissions, and the effects of climate change on a proposed action. The memorandum applies to all types of proposed federal agency actions that are subject to NEPA analysis and guides agencies on how to address the greenhouse gas emissions from federal actions and the effects of climate change on their proposed actions within the existing NEPA regulatory framework.

This technical report focuses on sharing the collective efforts of the Inuit Circumpolar Council-Alaska, 146 Inuit contributing authors, a 12-member Food Security Advisory Committee, and many other Inuit who provided input and guidance to the process. The report aspires to strengthen the evidence base of (1) what Inuit food security is, (2) what the drivers of food (in)security are, and (3) identify information needed to conduct an assessment through the development of a conceptual framework. The assessment tool is designed to build the baseline of information needed to understand the Arctic environment and allow a pathway for assessments (food security, ecosystem, political, cultural, etc.) to link eco- and socio- components of sciences and indigenous knowledge.

The National Climate Assessment assesses the science of climate change and its impacts across the United States, now and throughout this century. It documents climate change-related impacts and responses for various sectors and regions, with the goal of better informing public and private decision making at all levels.

The assessment draws from a large body of scientific peer-reviewed research, technical input reports, and other publicly available sources; all sources meet the standards of the Information Quality Act. The report was extensively reviewed by the public and experts, including a panel of the National Academy of Sciences, the 13 federal agencies of the U.S. Global Change Research Program, and the Federal Committee on Environment, Natural Resources, and Sustainability.

President Obama's Climate Action Plan includes a series of executive actions to reduce carbon pollution, prepare the United States for the impacts of climate change, and lead international efforts to address global climate change.

In determining appropriate adaptation strategies, project staff worked with participants to survey a wide range of potential strategy options and develop a process for evaluation and prioritization of targeted strategies.