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United States
Environmental Protection
Agency
         Climate Change  in  the United States:
                      Benefits of Global Action
A new EPA report, Climate Change in the United States: Benefits of Global Action,
explores the question: What are the benefits to the United States of reducing
global greenhouse gas emissions? To answer this, we need to understand the
basic scale of the difference between a world with and without global climate
action.This report summarizes peer-reviewed  results from the Climate
Change Impacts and Risks Analysis (CIRA) project, which estimates the physi-
cal and monetary benefits to the U.S. of global action on climate change. This
brochure provides key findings and regional highlights of the report, showing
that Americans significantly benefit from global action. Importantly, this
report analyzes only some of the impacts of climate change, and therefore
estimates just a portion of the total benefits of reducing GHGs.
    KEY FINDINGS
    • Global Action on Climate Change Avoids Costly Damages in the U.S. Across sectors, global greenhouse gas (GHG)
     mitigation (actions to reduce GHGs) is projected to prevent or substantially reduce adverse impacts in the U.S. this
     century compared to a future without emission reductions.

    • Global Action on Climate Change Reduces the Frequency of Extreme Weather Events and Associated Impacts.
     Global GHG reductions are projected to substantially reduce how often extreme temperature and precipitation
     events occur by the end of the century.

    • Global Action Now Leads to Greater Benefits over Time. For a majority of sectors, the benefits to the U.S. of GHG
     mitigation are projected to be even greater by the end of the century compared to the next few decades. Therefore,
     decisions we make today on GHG emissions have long-term effects, and delaying action increases the risks of
     significant and costly impacts in the future.

    • Adaptation Can Reduce Damages and Overall Costs in Certain Sectors. Though actions to prepare for climate
     change incur costs, they can be very effective in reducing certain impacts and will be necessary in addition to
     GHG mitigation.

    • Impacts are Not Equally Distributed. Some regions are more vulnerable than others and therefore will experience
     greater impacts.

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                                United States
                                Environmental Protection
                                Agency
Highlights  by Sector
Compared to a future of unchecked GHG emissions, global action on climate change is projected to provide
the following annual benefits to the U.S.1 The majority of these benefits (avoided impacts) are shown forthe
end of the century, assuming significant global action happens in the near term and continues. Importantly,
this report analyzes only some of the impacts of climate change, and therefore estimates just a portion of the
total benefits of reducing GHGs. While projecting decades into the future involves uncertainty, this report
shows a substantial difference between a world with and without global climate action, making a clear case
that acting now is vital for the U.S.
HEALTH
Air Quality: An estimated 57,000 fewer deaths
annually from poor air quality in 21OO.2
Extreme Temperature: In 49 major U.S. cities, an
estimated 12,000 fewer deaths annually from extreme
temperature events in 2100. Adaptive measures could
also reduce the number of deaths.
Labor: Approximately $110 billion in avoided damages
annually from lost labor due to extreme temperatures
in 2100.
Water Quality: An estimated $2.6-$3.0 billion in
avoided damages annually from poor water quality in
2100.
INFRASTRUCTURE
Bridges: An estimated 720-2,200 fewer bridges made
structurally vulnerable annually from heavy river flows
in 2100.
Roads: An estimated $4.2-$7.4 billion in avoided
adaptation costs for roads annually in response to
changes in temperature and precipitation in 2100.
Urban Drainage: In 50 U.S. cities, an estimated $50
million-$6.4 billion in avoided adaptation costs
annually in response to heavy precipitation in 2100.
Coastal Property: Approximately $3.1 billion in
avoided damages and adaptation costs annually to
coastal property from sea level rise and storm surge in
2100.
ELECTRICITY
Electricity Demand: An avoided increase in demand
in 2050 of approximately 1.1%-4.0%dueto smaller
increases in temperature.
Electricity Supply: An estimated $10-$34 billion in
savings on power system costs in 2050.
WATER RESOURCES
Inland Flooding: Estimates range from approximately
$2.8 billion in avoided damages to $38 million in
increased damages annually in 2100.
Drought: An estimated 40%-59% fewer severe and
extreme droughts in 2100.
Supply and Demand: An estimated $11-$180 billion
in avoided damages annually from water shortages in
key economic sectors in 2100.


AGRICULTURE AND FORESTRY
Agriculture: An estimated $6.6-$11 billion annually in
avoided damages to agriculture in 2100.
Forestry: An estimated $520 million to $1.5 billion
annually in avoided damages to forestry in 2100.


ECOSYSTEMS
Coral Reefs: An avoided loss of approximately 35%
of current Hawaiian coral in 2100, with an annual
recreational value of $1.1 billion.
Shellfish: An avoided loss of approximately 34% of the
U.S. oyster supply, 37% of scallops, and 29% of clams
in 2100.
Freshwater Fish: An estimated 230,000-360,000 acres
of cold-water fish habitat preserved in 2100.
Wildfire: An estimated 6.0-7.9 million fewer acres
burned annually by wildfires in 2100.
Carbon Storage: An estimated 1.0-26 million fewer
tons of carbon stored in vegetation in 2100.
1 The results presented here correspond to a GHG emissions reduction scenario that limits future global temperature increase to 2°C (3.6°F)
 above preindustrial levels. Unless otherwise noted, the results presented here are undiscounted estimates of annual benefits (or disbenefits) of
 GHG reductions in the year 2100 for the contiguous U.S. None of the estimates presented should be interpreted as definitive predictions of
 future impacts at a particular place or time. For detailed information on the results, including the supporting methods and assumptions, please
 refer to the main report.

2 The analysis held emissions of traditional air pollutants constant at current levels to isolate the climate change related impact on air quality.
 As such, the substantial benefits to air quality and health that would stem from the co-control of traditional air pollutants along with GHG
 emissions are not included here.

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                        United States
                        Environmental Protection
                        Agency
Regional  Highlights
The following highlights from the CIRA report provide examples of climate change impacts in U.S. regions, focusing on the risks of inaction and/or
the benefits of global action on climate change.3 As these results were primarily developed to analyze changes at a national-scale, precision at local
scales should not be assumed in most sectors.
NORTHWEST
• In the Pacific Northwest, unmitigated climate
 change is projected result in $120-340
 million in damages due to decreased water
 quality in 2100. Global action on climate
 change would avoid approximately $100-260
 million of these damages.

• In the Pacific Northwest, approximately 56%
 (8,300) of inland bridges are projected to
 become vulnerable in the second half of the
 century due to unmitigated climate change.
 Global action on climate change would reduce
 this number to 25% or approximately 3,700.

• Throughout the Northwest, unmitigated
 climate change is projected to result in the loss
 of a substantial amount of the habitat currently
 suitable for coldwater fisheries, which supports
 valuable species such as trout. Global action on
 climate change is projected to preserve nearly
 all of this habitat.

• In the Northwest, unmitigated climate change
 is projected to increase area burned by
 wildfire annually by approximately 95% by the
 end of the century.

• In the national market, ocean acidification is
 projected to result in a 32-48% decline in the
 harvest of select shellfish by the end of the
 century. Global action on climate change
 could prevent most of the decreases in supply,
 therefore avoiding an estimated $380 million
 in consumer losses in 2100.
MIDWEST
• In 11 major cities of the Midwest, unmiti-
 gated climate change is projected to result
 in approximately 1,700 deaths in 2100 due
 to extreme temperatures. Global action on
 climate change, which would reduce future
 increases in temperature, is estimated to
 avoid 87% of these deaths. Adaptive
 measures are also likely to reduce the
 number of expected deaths.

• In the Great Lakes region, approximately
 37% (7,900) of inland bridges are projected
 to become vulnerable in the second half of
 the century due to unmitigated climate
 change. Global action on climate change
 would reduce this number to 9% or
 approximately 2,000.

• In many large cities in the Midwest, unmiti-
 gated climate change is projected to result
 in average adaptation costs per square mile
 of up to $1 million in 2100 associated with
 impacts from extreme precipitation events
 on urban drainage infrastructure.

• In the Great Lakes region, global action on
 climate change is projected to decrease
 inland flooding damages by 13%-38% in
 2100 compared to a future with no GHG
 emission reductions.
NORTHEAST
• In eight major cities of the Northeast and
 Mid-Atlantic, unmitigated climate change is
 projected to result in approximately 2,600
 deaths in 2100 due to extreme temperatures.
 Global action on climate change, which
 would reduce future increases in tempera-
 ture, is estimated to avoid 93% of these
 deaths. Adaptive measures are also likely to
 reduce the number of expected deaths.

• In New England, unmitigated climate
 change is projected to result in $60-90
 million in damages due to decreased water
 quality. Global action on climate change
 would avoid approximately $77-89 million of
 these damages in 2100.

• In the Mid-Atlantic, approximately 76%
 (24,000) of inland  bridges are projected
 to become vulnerable in the second half
 of the century due to unmitigated climate
 change. Global action on climate change
 would reduce this number to 35% or
 approximately 11,000.

• Coastal properties in the Northeast are at risk
 of significant economic damages from sea
 level rise and storm surge. In New Jersey and
 Delaware, the costs of adaptive responses,
 such as beach nourishment and property
 elevation, are estimated at approximately
 $21 billion (discounted at 3%) through 2100.

• Throughout the Appalachians, unmitigated
 climate change is projected to result in
 the loss of nearly all of the habitat currently
 suitable for coldwater fisheries, which
 supports valuable species such as trout.
 Global action on climate change is projected
 to preserve approximately 70% of this
 habitat.
3 This brochure presents a selection of the estimated benefits of global GHG mitigation for regions of the contiguous U.S.
 and Hawaii (regions loosely defined as those used in the U.S. Global Change Research Program's Third National Climate
 Assessment, nca2014.globalchange.gov). These regional highlights were developed using results presented in the
 report the underlying literature, and in the accompanying data available at www2.epa.gov/cira/downloads-cira-report.

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                      United States
                      Environmental Protection
                      Agency
Regional Highlights (continued)
SOUTHWEST AND HAWAII  	
• In California, global action on climate
 change is projected to result in 39-75%
 fewer severe and extreme droughts by the
 end of the century compared to a future
 with no GHG emission reductions.

• In some areas of California, unmitigated
 climate change is projected to increase area
 burned by wildfire annually by approximate-
 ly 45% by the end of the century.

• In the Southwest, particularly Arizona
 and Southern California, changes in
 extreme temperatures due to unmitigated
 climate change are projected to reduce
 hours worked in outdoor labor industries
 (e.g., construction) by up to 7% in 2100,
 equating to millions of lost labor hours.
 Global action on climate change would limit
 lost labor hours to no more than 2.9%

• In Arizona, Nevada, and California, unmiti-
 gated climate change is projected to result
 in $1.5-2.2 billion in damages due to
 decreased water quality. Global action on
 climate change would avoid approximately
 $1.3-1.7 billion of these damages in 2100.

• In Hawaii, unmitigated climate change is
 projected to result in coral cover declining
 from about 38% today to less than 1% by
 the end of the century. Global action on
 climate change could avoid approximately
 35% of this loss, saving $20 billion in
 recreational activity through 2100 (dis-
 counted at 3%).
  To view and download
  the full report, visit:
  www.eDa.aov/cira
   EPA 430-F-15-023
   June 2015
GREAT PLAINS
• In the southern states of the Great Plains,
 changes in extreme temperatures due to
 unmitigated climate change are projected
 to reduce hours worked in outdoor labor
 industries (e.g., construction) by up to 7%
 in 2100. Global action on climate change
 would limit lost labor hours to no more
 than 3.9%.

• In many large cities in the Great Plains,
 unmitigated climate change is projected to
 result in average adaptation costs per
 square mile of up to  $2.1  million in 2100
 associated with impacts from extreme
 precipitation events  on urban drainage
 infrastructure.

• In the southern states of the Great Plains,
 rising demand for air conditioning is
 projected to increase total electricity demand
 by 2%-4% in 2050 due to unmitigated
 climate change.

• Throughout the Mountain West, unmitigated
 climate change is projected to result in the
 loss  of a substantial amount of the habitat
 currently suitable for coldwater fisheries,
 which supports valuable species such as
 trout. Global action on climate change is
 projected to preserve nearly all of this habitat.

• In the Mountain West, unmitigated climate
 change is projected to increase area burned
 by wildfire annually by approximately 64% by
 the end of the century.
SOUTHEAST
• In the Southeast, changes in extreme
 temperatures due to unmitigated climate
 change are projected to reduce hours
 worked in outdoor labor industries (e.g.,
 construction) by up to 7% in 2100. Global
 action on climate change would limit lost
 labor hours to no more than 3%.

• In South Atlantic-Gulf region, unmitigated
 climate change is projected to result in
 $410-430 million in damages due to
 decreased water quality. Global action on
 climate change would avoid approximately
 $320-360 million of these damages in 2100.

• In the South Atlantic-Gulf region, up to
 approximately 41% (26,000) of inland
 bridges are projected to become vulnerable
 in the second half of the century due to
 unmitigated climate change. Global action
 on climate change would reduce this
 number to 9% or approximately 5,600.

• Coastal properties in the Southeast are at
 risk of significant economic damages from
 sea level rise and storm surge. FortheTampa
 area, the costs of adaptive responses, such
 as beach nourishment and property
 elevation, are estimated at approximately
 $90 billion (discounted at 3%) through 2100.

• In the Southeast, rising demand for air
 conditioning is projected to increase total
 electricity demand by 2%-6% in 2050 due
 to unmitigated climate change.

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