Climate assessment activities are increasingly driven by subnational organizations—city, county, and state governments; utilities and private companies; and stakeholder groups and engaged publics—trying to better serve their constituents, customers, and members by understanding and preparing for how climate change will impact them locally. Whether the threats are drought and wildfires, storm surge and sea level rise, or heat waves and urban heat islands, the warming climate is affecting people and communities across the country. To explore the growing role of subnational climate assessments and action, the National Academies of Sciences, Engineering, and Medicine hosted the 2-day workshop Making Climate Assessments Work: Learning from California and Other Subnational Climate Assessments1 on August 14-15, 2018, with sponsorship from the California Energy Commission and the Electric Power Research Institute.
Based on a statement of task negotiated with the sponsors (Appendix A), a workshop agenda (Appendix B) was developed by a volunteer planning committee (Appendix C) to (1) call attention to examples of subnational leadership in initiating, conducting, implementing, and sustaining climate assessment activities; (2) identify and disseminate effective practices and strategies for engaging local stakeholders and translating relevant climate science for decision makers; and (3) engage and build a network of participants involved with national and subnational climate assessment and adaptation activities across the United States. More than 450 participants (Appendix D) registered for the 2-day workshop. This document summarizes the presentations and discussions that occurred over the course of the workshop. Any statements or opinions contained in this proceedings are those of the individual participants and do not represent the views of the participants on a whole, the planning committee, or the National Academies of Sciences, Engineering, and Medicine.
K. JOHN HOLMES, NATIONAL ACADEMIES OF SCIENCES, ENGINEERING, AND MEDICINE
In introducing the workshop, K. John Holmes, director of the Board on Energy and Environmental Systems, explained that the first day of the workshop focused on California’s Fourth Climate Change Assessment (State of California, 2018)—a collection of more than 50 independent research projects spanning the state’s geography and numerous economic sectors—with an emphasis on stakeholder engagement and use of this information in decision making. The second day surveyed diverse state- and sector-specific assessment activities from across the
country, ranging from Hawaii to New York and many places in between. The panels explored strategies and practices common across the numerous assessments that contributed to better understanding and use of the scientific information produced. The panels also allowed participants to learn collectively from each other’s efforts. Climate assessment begins the process of adaptation, but it does not end there, said Holmes. There must be mechanisms to sustain and evolve the assessment process and to operationalize its findings, he continued, and these topics were explored in a breakout activity and closing panel of the workshop.
Holmes ended his remarks with a personal observation, recalling when he came to Washington, D.C., 30 years ago. In June of that year (1988), James Hanson appeared before the Senate Energy and Natural Resources Committee and testified that global warming was real and had begun. Remembering the summer of 1988, Holmes recalled that half the days in Washington were above 90°F and a handful, including the day Hanson testified, above 100°F. He concluded that it was impossible to say whether that summer heat wave back in 1988 was climate change but, 30 years later, the debate has moved from scientific debates over the existence of climate change to discussions of assessment, adaptation, and mitigation activities. That was the context for this workshop.
ROBERT WEISENMILLER, CALIFORNIA ENERGY COMMISSION
Robert Weisenmiller, chair of the California Energy Commission, opened the workshop by citing Governor Jerry Brown’s public comments that climate change is one of two existential challenges facing the world, alongside nuclear proliferation. California has conducted significant research to inform fact-based adaptation and mitigation strategies, and the workshop will be able to cover only a small portion of this work, he said. Currently, California is being ravaged by wildfires that are growing in frequency and damage—major fires historically occurred once a decade, whereas the past 10 years have seen nine of the largest fires in the state’s history—and this is a global problem with fires burning in countries like Greece and Sweden. Weisenmiller quoted a recent New York Times article stating that “For many scientists, this is the year they started living climate change rather than just studying it” (Sengupta, 2018) and a recent article in the Economist describing how economic and political inertia can make it difficult to enact significant change (Economist, 2018). However, he noted that subnational organizations and states have often acted as laboratories for policy and innovation, and California has contributed through producing rigorous climate change assessments.
Weisenmiller provided a brief history of climate assessments in California (Table 1.1), noting that each has built on the previous and had meaningful outcomes. He enthusiastically previewed early findings from the Fourth Assessment (Bedsworth et al., 2018), which contains technical and regional reports designed to support adaptation actions at the state, sub-state, regional, and local level. He noted several differences between the Fourth Assessment and previous efforts, including the increasing sophistication of downscaling approaches for climate projections and the broader scope of projects beyond energy resources and infrastructure funded by other state agencies.
Reflecting on key takeaways from the Fourth Assessment, Weisenmiller commented that in some places action on the ground is moving faster than scientific research can keep pace. He noted that the nearly 50 studies comprising the Fourth Assessment, all of which have undergone peer review, consider common climate scenarios, and their results have been summarized in an accessible manner for a general audience. A theme across the studies is a trend toward greater variability and higher extremes, for example in temperature, which he illustrated showing the projected number of days exceeding 103°F in Sacramento over the coming decades, and this in turn increases the likelihood of wildfires. The number of structures damaged by wildfires in 2017 alone was similar to the cumulative number damaged during the previous 10 years, he said, and the 2018 Mendocino Complex fire is the largest to date. In addition to wildfires, the Fourth Assessment explores many other topics, including projected sea level rise and winter storm surges. The greater variability and higher extremes forecast for California can bring significant damages, concluded Weisenmiller, so the state and local governments need to accelerate their adaptation efforts.
TABLE 1.1 History of California Climate Assessments, Their Characteristics, Drivers, and Outcomes
|Year||First California Climate Assessment 2006||Second California Climate Assessment 2009||Third California Climate Assessment 2012||Fourth California Climate Assessment 2018|
|Description||Understanding climate impacts in California. Developed to provide support for undertaking greenhouse gas emissions reductions.||Understanding how climate change will affect specific sectors. Made the case that adaptation could reduce costs.||Increased understanding of vulnerability in natural and human systems, and generated two pilot regional assessments.||Technical and regional reports designed to support adaptation actions at the state, regional, and local level.|
|Driver||Executive Order S-3-05||Policymakers’ desire to know if adaptation was needed||2009 Climate Adaptation Strategy||2015 Climate Change Resilience Plan|
|Outcome||Assembly Bill (AB) 32||2009 Climate Adaptation Strategy||Supported passage of new climate adaptation laws||Informing the implementation of AB 2800, which requires a report on how engineering standards should be changed to consider climate change. Other outcomes to be determined.|
SOURCE: Bedsworth et al. (2018).
Craig Zamuda, U.S. Department of Energy (DOE), asked Weisenmiller what the federal government can do to assist California and other states in addressing the challenges of a more variable and extreme climate. Weisenmiller responded that Governor Jerry Brown has declared a state of emergency in reaction to the California wildfires, which prompted the federal government to step up as a partner. However, because most of the U.S. Forest Service’s budget is increasingly allocated to fire suppression, there is not sufficient funding available for treating forested land, which can improve ecosystem health and decrease the likelihood of future fires. This is an area where the federal government could help significantly, said Weisenmiller, because forest treatment will be a growing issue as development continues to occur in fire-prone areas. Weisenmiller also highlighted the work done by DOE’s Partnership for Energy Sector Climate Resilience2 to help electric utilities conduct climate vulnerability assessments and commit to implementing adaptation strategies. Regarding mitigation efforts, Weisenmiller commented that he would like to see the United States reenter the Paris Climate Accord, because the extent of adaptation required will be less if emissions can be reduced.
Bob Yukne, Elders for Climate Action, asked about the extent to which the Fourth Assessment addresses reductions in agricultural production. Weisenmiller explained that the assessment does include studies that focus on prolonged drought and other adaptation challenges for agriculture (e.g., Medellin-Azuara et al., 2018; Flint et al., 2018), as it is one of California’s largest industries and droughts can have huge impacts on production. To close this session, Bruce Riordan, Climate Readiness Institute, asked Weisenmiller what the key is to securing dedicated and increased funding for local and regional governments to take on climate adaptation, on a scale analogous to mitigation. Weisenmiller acknowledged that this is a primary challenge and that the key is engaging and communicating with people around the issue to convince them that it is a serious threat that needs to be addressed.
2 U.S. Department of Energy, “Partnership for Energy Sector Climate Resilience,” https://www.energy.gov/policy/initiatives/partnership-energy-sector-climate-resilience.
Bedsworth, L., D. Cayan, G. Franco, L. Fisher, and S. Ziaja. 2018. “Statewide Summary Report.” California’s Fourth Climate Change Assessment. SUMCCCA4-2018-013. http://www.climateassessment.ca.gov/state/docs/20180827-StatewideSummary.pdf.
Economist. 2018. “The World Is Losing the War Against Climate Change.” August 2. https://www.economist.com/leaders/2018/08/02/the-world-is-losing-the-war-against-climate-change.
Flint, L., A. Flint, M. Stern, A. Mayer, S. Vergara, W. Silver, F. Casey, et al. 2018. “Increasing Soil Organic Carbon to Mitigate Greenhouse Gases and Increase Climate Resiliency for California.” California’s Fourth Climate Change Assessment. CCCA4-CNRA-2018-006. http://www.climateassessment.ca.gov/techreports/docs/20180827-Agriculture_CCCA4CNRA-2018-006.pdf.
Medellín-Azuara, J., D.A. Sumner, Q. Y. Pan, H. Lee, V. Espinoza, S.A. Cole, A. Bell, et al. 2018. “Economic and Environmental Implications of California Crop and Livestock, Adaptation to Climate Change.” California’s Fourth Climate Change Assessment. CCCA4-CNRA-2018-018. http://www.climateassessment.ca.gov/techreports/docs/20180827-Agriculture_CCCA4-CNRA-2018-018.pdf.
Sangupta, S. 2018. “2018 Is Shaping Up to Be the Fourth-Hottest Year. Yet We’re Still Not Prepared for Global Warming.” New York Times. August 9. https://www.nytimes.com/2018/08/09/climate/summer-heat-global-warming.html.
State of California. 2018. California’s Fourth Climate Change Assessment. http://www.climateassessment.ca.gov/.