COLORADO CLIMATE CHANGE VULNERABILITY STUDY A report submitted to the Colorado Energy Office EDITORS Eric Gordon, University of Colorado Boulder Dennis Ojima, Colorado State University Colorado Climate Change Vulnerability Study A REPORT BY THE UNIVERSITY OF COLORADO BOULDER AND COLORADO STATE UNIVERSITY TO THE COLORADO ENERGY OFFICE January 2015 Editors Eric Gordon, University of Colorado Boulder Dennis Ojima, Colorado State University Lead Authors Amber Childress, Colorado State University Eric Gordon, University of Colorado Boulder Theresa Jedd, Colorado State University Roberta Klein, University of Colorado Boulder Jeff Lukas, University of Colorado Boulder Rebecca McKeown, Colorado State University Acknowledgements The authors would like to thank Jeffrey Ackermann, Tom Hunt, and Michael Turner from the Colorado Energy Office as well as Taryn Finnessey from the Colorado Water Conservation Board for their assistance and guidance. In addition to the many experts and reviewers listed separately, the authors received valuable input from Jeff Lukas, Bill Travis, Kristen Averyt, Imtiaz Rangwala at the University of Colorado Boulder, and Stephen Saunders of the Rocky Mountain Climate Organization. Copyright © 2015 University of Colorado Boulder and Colorado State University Funding for this study was provided by the Colorado Energy Office Cover Photos iStock: JuliScalzi; Sgt. Jeremy Lock, U.S. Air Force; T. H. Painter, Snow Optics Laboratory, JPL/ Caltech; Wikimedia Commons, Daniel Schwen Design and Layout Ami Nacu-Schmidt and Nancy Filice We would like to offer special thanks to those individuals who lent their time and expertise to reviewing the chapters herein. Sector Experts Kristen Averyt, University of Colorado Boulder Lenora Bohren, Colorado State University William D. Bowman, University of Colorado Boulder Tom Bradley, Colorado State University Antony S. Cheng, Colorado State University Paul Chinowsky, University of Colorado Boulder Veva Deheza, University of Colorado Boulder Mary Hayden, National Center for Atmospheric Research Eugene Kelly, Colorado State University Shannon McNeeley, Colorado State University Dennis Ojima, Colorado State University Andrew Seidl, Colorado State University Melinda Smith, Colorado State University Lorann Stallones, Colorado State University William Travis, University of Colorado Boulder Carol Wessman, University of Colorado Boulder Olga Wilhelmi, National Center for Atmospheric Research Reviewers Jeff Ackermann, Colorado Energy Office Steve Adams, Institute for Sustainable Communities Ray Alvarado, Colorado Water Conservation Board Elizabeth Carlton, University of Colorado Denver Lisa Dale, Colorado Department of Natural Resources Taryn Finnessey, Colorado Water Conservation Board Elizabeth Garner, State Demographer Walt Hecox, Colorado College Vanessa Henderson, Colorado Department of Transportation Art Hirsch, TerraLogic Tom Hunt, Colorado Energy Office Paul Komor, University of Colorado Boulder Joshua Laipply, Colorado Department of Transportation Cindy Lair, Colorado Department of Agriculture John Loomis, Colorado State University Sarah Mitchell, Colorado Department of Transportation Dick Parachini, Colorado Department of Public Health and Environment Lori Peek, Colorado State University Gary Peterson, Colorado State University Gigi Richard, Colorado Mesa University Bryan Roeder, Colorado Department of Transportation Bill Romme, Colorado State University Stephen Saunders, Rocky Mountain Climate Organization Tim Seastedt, University of Colorado Boulder Joel Smith, Stratus Consulting Theresa Takushi, Colorado Department of Public Health and Environment Michael Turner, Colorado Energy Office Mike Van Dyke, Colorado Department of Public Health and Environment Reagan Waskom, Colorado State University Al White, Colorado Tourism Office Table of Contents EXECUTIVE SUMMARY i CHAPTER 1: INTRODUCTION AND PURPOSE OF STUDY 1 I. Introduction 1 II. Climate and Colorado’s History 4 III. Structure of Report 6 CHAPTER 2: COLORADO’S CLIMATE: PAST AND FUTURE 9 I. Introduction 9 II. Observed Climate in Colorado 10 III. An Overview of the Projected Mid-Century Climate in Colorado 11 CHAPTER 3: DEMOGRAPHY, LAND USE, AND ECONOMICS 15 I. Introduction 16 II. Demography 16 III. Land Use 19 IV. Economy 23 CHAPTER 4: ECOSYSTEMS SECTOR 31 I. Brief Description of Sector 32 II. Key Climate Impacts to Sector 34 III. Key Vulnerabilities 39 IV. Moving Toward Preparedness 42 V. Future Research Needs 43 CHAPTER 5: WATER SECTOR 53 I. Brief Description of Sector 54 II. Key Climate Impacts in Sector 57 III. Vulnerability in Colorado’s Water Sector 61 IV. Moving Toward Preparedness 67 V. Future Research Needs 68 CHAPTER 6: AGRICULTURE SECTOR 75 I. Background 76 II. Key Climate Change Impacts 78 III. Key Vulnerabilities and Adaptability in Agriculture 82 IV. Moving Toward Preparedness 84 V. Future Research Needs 85 CHAPTER 7: ENERGY SECTOR 89 I. Brief Description of Sector 90 II. Key Climate Impacts to Sector 91 III. Key Vulnerabilities 97 IV. Moving Toward Preparedness 103 V. Future Research Needs 103 CHAPTER 8: TRANSPORTATION SECTOR 109 I. Brief Description of Sector 110 II. Key Climate Impacts to Sector 112 III. Key Vulnerabilities in Sector 117 IV. Moving Toward Preparedness 120 V. Future Research Needs 121 CHAPTER 9: OUTDOOR RECREATION AND TOURISM SECTOR 127 I. Brief Description of Sector 128 II. Key Climate Impacts to Sector 131 III. Key Vulnerabilities 136 IV. Moving Toward Preparedness 138 V. Future Research Needs 138 CHAPTER 10: PUBLIC HEALTH SECTOR 145 I. Background 146 II. Key Climate Change Impacts 148 III. Key Vulnerabilities 154 IV. Moving Toward Preparedness 155 V. Future Research Needs 156 CHAPTER 11: MOVING TOWARD PREPAREDNESS 161 I. What Are Adaptation and Preparedness? 162 II. What Are the Key Elements of Adaptation/Preparedness? 162 III. How Can State Agencies and Other Entities Begin Preparedness Planning? 164 IV. How Should State Agencies Begin Preparedness Planning? 167 V. How Have Other States Approached Adaptation Planning? 169 APPENDIX A: “WEATHERING CHANGE” WORKSHOP 175 COLORADO CLIMATE CHANGE VULNERABILITY STUDY Damage from the 2002 Hayman Fire is evident 12 years later in this May 2014 panoramic image of the Lost Creek Wilderness. Photo: Eric Gordon. EXECUTIVE SUMMARY Overview of Report Colorado’s climate has warmed in recent Energy Office commissioned the University decades, and climate models unanimously of Colorado Boulder and Colorado State project this warming trend will continue University to assemble a team of Colorado- into the future. Climate change has and will based experts to complete this study, as one continue to impact the state’s resources in initial step in a multi-agency response to the a variety of ways, including more rapid requirements of HB 13-1293. snowmelt, longer and more severe droughts, and longer growing seasons. Moreover, The Colorado Climate Change Vulnerability Colorado experiences numerous climate- Study provides an overview of key related disasters, such as floods, droughts, vulnerabilities that climate variability and and wildfires, which will continue to occur in change will pose for Colorado’s economy the future and pose serious hazards to public and resources. The purpose of the study is safety and the economy, regardless of the rate to provide state agencies, local governments, at which the climate warms. and others with background for preparedness planning. During its 2013 session, the Colorado Legislature passed HB13-1293, which declared “Key vulnerabilities” are defined as “those that “climate change presents serious, diverse, aspects of the state’s economy, resources, or and ongoing issues for the state’s people, populations that experience negative effects economy, and environment.” Among other from climate variability or change, and that provisions, the bill required the governor lack sufficient capacity to adapt to those to submit an annual report to a number of effects.” Vulnerability is a function of both committees within the legislature “on climate impacts (the effects of climate variability or change issues generally, the current climate climate change on a given system or resource) action plan…and the specific ways in which as well as adaptive capacity (the ability of climate change affects the state.” The Colorado the economy, resources, or population to i EXECUTIVE SUMMARY effectively adapt to such events and changes). • Multiple droughts prior to 1900 that were The report analyzes vulnerabilities related to more severe and sustained than any in both current climate variability—including the observed record, as seen in tree-ring extreme weather events—and future climate records. change. Projections from Global Climate Models (GCMs), under a mid-range emissions scenario, indicate the a number of changes Colorado’s Climate: Past and continued uncertainties for Colorado’s and Future History climate in the mid-21st century: Chapter 2 of this report provides a brief • An increase in statewide average annual summary of Climate Change in Colorado (http:// temperatures of 2.5°F to 5.5°F relative to a wwa.colorado.edu/climate/co2014report), 1971–2000 baseline. Summers are projected which synthesizes observed climate and to warm slightly more than winters. Typical projected future climate for the state of summer temperatures in 2050 are projected Colorado. Historic observations of Colorado’s to be warmer than in all but the very hottest climate include: summers in the observed record. • An increase in statewide annual average • Climate projections