1 Global Climate Change Impacts in the United States

2 How has climate already changed? How is it likely to change in the future? How is climate change affecting us now where we live and work? How is it likely to affect us in the future? What are our options for responding?

33 This report provides information we need.... to make good decisions at the national, regional, and local levels so we can avoid some of the impacts we’ll be talking about today to be able to better understand the consequences of our decisions about emissions as well as adaptation

44 Climate changes are underway now in the U.S., and are projected to grow Temperature rise Sea-level rise Increase in heavy downpours Less snow and earlier snowmelt lead to changes in river flows

5 Global Average Temperature, 1900 to 2100 Temperatures will continue to rise − by how much depends largely on the amount of heat-trapping gases in the atmosphere.

6 Number of Days Over 100ºF Increases in very high temperatures will have wide-ranging effects. Recent Past, Higher Emissions Scenario, Lower Emissions Scenario,

7 Projected Increase in Heat-Related Deaths in Chicago Heat-related illnesses and deaths are projected to increase, especially in cities.

8 Observed Increases in Very Heavy Precipitation (1958 to 2007) Heavy downpours have increased across the nation and are projected to increase further.

9 Projected Change in Precipitation by s Water resources will be affected by changing precipitation patterns and increasing temperatures.

10 Agriculture will face challenges from increased heat, pests, water stress, diseases, and weather extremes. ©Copyright

11 Florida with 3 feet of Sea-Level Rise Areas in red would be under water with a 3 foot rise in sea level, projected for this century Coastal areas are at increasing risk from sea-level rise and storm surge.

12 Gulf Coast Area Roads at Risk from Sea-Level Rise Energy and transportation infrastructure in coastal areas faces increasing risk.

13 Climate change will affect many aspects of our lives as it alters the character of every region. ©Copyright

14 Ocean Acidification

15 Decreasing Habitat for Coldwater Fish Based on a Higher Emissions Scenario WA OR ID Thresholds will be crossed, leading to large changes in ecosystems.

16 Water and Energy Interactions Various effects of climate change will interact, compounding and amplifying impacts. ©Copyright

17 Response Strategies “Mitigation” – reducing the amount of climate change, for example, by reducing heat-trapping emissions or increasing their removal from the atmosphere “Adaptation” – improving our ability to cope with or avoid harmful impacts or taking advantage of newly favorable conditions Both will be needed.

18 globalchange.gov/usimpacts