21st Century Operations Using 21st Century Technologies
Table of Contents

Planning for Systems Management & Operations as part of Climate Change Adaptation

Appendix A – Climate Change Impact Tables

Table A.1. Transportation-Relevant Climate Change Effects Associated with Climate Trends.
Category Climate Impact Region Date Range Certainty Reference
Air Temperature Increase in average annual air temperature CONUS 2001-2100 Very likely Christensen et al., 2007
Air Temperature Increase in average annual air temperature CONUS 2010-2029; 2040-2059 Very likely ICF International, 2010
Air Temperature Increase in diurnal air temperature ranges Western U.S. 2001-2100 empty cell Christensen et al., 2007
Air Temperature Increase in electricity demand for air conditioning during summer and decrease in electricity demand for heating in winter CONUS 2001-2100 High confidence Field et al., 2007
Air Temperature Increase in average winter temperatures CONUS 2010-2029; 2040-2059 Very likely ICF International, 2010
Precipitation Increase in average annual precipitation CONUS except south and southwestern U.S. 2001-2100 Very likely Christensen et al., 2007
Precipitation Increase in average annual precipitation Northeast U.S.
Northwest U.S.
Midwest U.S.		 2010-2029; 2040-2059 Very likely ICF International, 2010
Precipitation Increase in average annual precipitation Hawaii 2040-2059 Very likely ICF International, 2010
Precipitation Increase in average annual precipitation U.S. Great Plains 2010-2029 Very likely ICF International, 2010
Precipitation Increase in average annual precipitation U.S. Great Plains 2040-2059 Likely ICF International, 2010
Precipitation Decrease in average annual precipitation Southwest U.S. 2001-2100 Likely Christensen et al., 2007
Precipitation Increase in average precipitation during winter Northern U.S. 2001-2100 empty cell Christensen et al., 2007
Precipitation Increase in average precipitation during winter Northeast U.S.
Northwest U.S.
Southwest U.S.
U.S. Great Plains
Midwest U.S.		 2010-2029; 2040-2059 Very likely ICF International, 2010
Precipitation Decrease in average precipitation during summer Southern U.S. 2001-2100 empty cell Christensen et al., 2007
Precipitation Decrease in average precipitation during summer Northwest U.S.
Southwest U.S.
Southeast U.S.
U.S. Great Plains
Midwest U.S.
Hawaii		 2010-2029; 2040-2059 Very likely ICF International, 2011
Precipitation Change in seasonal precipitation and river flow patterns CONUS 2001-2100 empty cell Field et al., 2007
Sea Level and Coastal Impacts Rise in sea level Atlantic and Pacific coasts of U.S. 2001-2099 High confidence Meehl et al., 2007
Sea Level and Coastal Impacts Accelerated coastal erosion Atlantic and Pacific coasts of U.S. 2001-2100 Likely Field et al., 2007
Freshwater Resources Increase in precipitation runoff  CONUS 2001-2100 empty cell Field et al., 2007
Freshwater Resources Increase in length of erosion season and enhancement of inland erosion CONUS 2001-2100 Likely Field et al., 2007
Freshwater Resources Decrease in water quality CONUS 2001-2100 High confidence Field et al., 2007
Freshwater Resources Decrease in snow season length and snow depth CONUS 2001-2100 Very likely Christensen et al., 2007
Freshwater Resources Earlier melting and significant reductions in snowpack Rocky Mountains 2001-2100 High confidence Field et al., 2007
Freshwater Resources Lower water levels Great Lakes 2001-2100 High confidence Field et al., 2007
Freshwater Resources Decreased recharge of heavily utilized groundwater-based systems Southwest U.S. 2001-2100 High confidence Field et al., 2007
Freshwater Resources Local, regional, or state-wide shortages of drinking water CONUS 2001-2017 empty cell Field et al., 2007
Freshwater Resources Reduction in winter ice cover Great Lakes  2001-2100 empty cell USGCRP, 2009
Freshwater Resources Shorter ice cover period in shallow inland lakes Northern U.S. 2001-2100 empty cell Field et al., 2007
Freshwater Resources Decrease in surface and bottom water temperatures of lakes, reservoirs, rivers, and estuaries CONUS 2001-2100 empty cell Field et al., 2007
Human Health Impacts Increase in concentrations of tropospheric (surface) ozone and particulate matter (PM2.5) CONUS 2001-2050 empty cell Field et al., 2007
Human Health Impacts Increase in respiratory illness CONUS 2001-2100 empty cell USCCSP SAP 4.6, 2008
Human Health Impacts Increase in pollen production CONUS 2001-2100 Likely Field et al., 2007
Human Health Impacts Increase in heat-related deaths CONUS 2001-2100 empty cell USCCSP SAP 4.6, 2008
Human Health Impacts Increase in extent of Lyme disease Northern U.S. 2001-2080 empty cell Field et al., 2007
Ecological Impacts Increase in length of growing season CONUS 2001-2100 Medium confidence Field et al., 2007
Ecological Impacts Expanded range of invasive species (general) CONUS 2001-2100 empty cell USCCSP SAP 4.4, 2008

Table A.2. Transportation-Relevant Climate Change Effects Associated with Distinct Climate Events.
Category Climate Impact Region Date Range Certainty Reference
Air Temperature Events Increase in intensity, frequency, and duration of heat waves CONUS 2001-2100 High confidence Field et al., 2007
Air Temperature Events Increase in intensity, frequency, and duration of heat waves Midwest U.S. by 2100 empty cell USGCRP, 2009
Air Temperature Events Increase in frequency and duration of extreme high temperature events and decrease in extreme low temperature events CONUS 2001-2100 empty cell Christensen et al., 2007
Precipitation Events Increase in intensity and frequency of extreme precipitation events CONUS 2001-2100 empty cell Christensen et al., 2007
Precipitation Events Greater variability in precipitation events CONUS 2001-2100 empty cell Meehl et al., 2007
Precipitation Events Greater variability in precipitation events Southwest U.S. empty cell empty cell USGCRP, 2009
Storms and Coastal Flooding Slight poleward shift in storm tracks of extra-tropical cyclones Mid-latitudes
(30-60 °N)		 2001-2100 empty cell Christensen et al., 2007
Storms and Coastal Flooding Increase in intensity but reduction in frequency of extra-tropical cyclones Mid-latitudes
(30-60 °N)		 2001-2100 empty cell Christensen et al., 2007; Meehl et al., 2007
Storms and Coastal Flooding Increase in peak wind speeds and precipitation intensities of hurricanes Atlantic and Eastern Pacific coasts of U.S. 2001-2102 empty cell Meehl et al., 2007
Storms and Coastal Flooding Increase in frequency and severity of coastal flooding events Atlantic and Pacific coasts of U.S. 2001-2100 Very high confidence Field et al., 2007
Storms and Coastal Flooding Increase in storm surge Atlantic and Pacific coasts of U.S. 2001-2101 High confidence Field et al., 2007
Wildfires More frequent wildfires that cover larger geographic areas CONUS 2001-2100 empty cell Field et al., 2007

Table A.3. Transportation-Relevant Climate Change Effects for Alaska.
Category Climate Impact Region Date Range Certainty Reference
Air Temperature Increase in average annual air temperature at higher rate than CONUS Alaska 2001-2100 Very likely Christensen et al., 2007
Precipitation Increase in average annual precipitation Alaska 2001-2100 Very likely Christensen et al., 2007
Precipitation Increase in average annual precipitation Alaska 2010-2029; 2040-2059 Very likely ICF International, 2010
Precipitation Increase in frequency of very warm and wet winters and summers Alaska 2001-2100 empty cell Christensen et al., 2007
Precipitation Increase in average precipitation during winter Alaska 2010-2029; 2040-2059 Very likely ICF International, 2010
Ice, Snow, and Permafrost Thinning and reduction in extent and thickness of annually averaged Arctic sea ice Alaska 2001-2100 Very likely Christensen et al., 2007
Ice, Snow, and Permafrost Warming, thawing, and decrease in areal extent of terrain underlain by permafrost Alaska (Arctic) 2001-2100 empty cell Anisimov et al., 2007
Ice, Snow, and Permafrost Reduction in seasonal snow cover on land Alaska (Arctic) 2001-2101 empty cell Anisimov et al., 2008
Storms Reduction in medium-strength extra-tropical cyclones Poleward of 70 °N 2001-2100 empty cell Christensen et al., 2007

Table A.4. Likelihood Terminology for Climate Change Effects.
[Adapted from Le Treut et al., 2007]
IPCC Likelihood Terminology Likelihood of the Impact
Virtually certain > 99% probability
Extremely likely > 95% probability
Very likely > 90% probability
Likely > 66% probability
More likely than not > 50% probability
About as likely as not 33 to 66% probability
Unlikely < 33% probability
Very unlikely < 10% probability
Extremely unlikely < 5% probability
Exceptionally unlikely < 1% probability

Table A.5. Confidence Terminology for Climate Change Effects.
[Adapted from Le Treut et al., 2007]
IPCC Confidence Terminology Degree of Confidence in Being Correct
Very high confidence At least 9 out of 10 chance
High confidence About 8 out of 10 chance
Medium confidence About 5 out of 10 chance
Low confidence About 2 out of 10 chance
Very low confidence Less than 1 out of 10 chance