The Earth's climate is undergoing significant changes, including rising temperatures and shifts in precipitation patterns.
More extreme climate events, such as heavy rainstorms and record-high temperatures, are occurring.
Scientific consensus strongly links these changes to increased levels of carbon dioxide and other greenhouse gases in the atmosphere due to human activities.
The EPA collaborates with over 40 data contributors from various government agencies and academic institutions to monitor climate change indicators.
These indicators are based on long-term observations and peer-reviewed data.
The indicators provide evidence of ongoing climate change in the United States and globally.
Key Climate Change Indicators
Atmospheric Concentrations of Greenhouse Gases: Current global atmospheric concentrations of carbon dioxide are unprecedented in the last 800,000 years.
U.S. and Global Temperature: Average temperatures have increased across the contiguous 48 states since 1901. Global temperatures show a similar trend, with the warmest years on record occurring since 1998.
Coastal Flooding: Coastal flooding is becoming more frequent along the U.S. coastline due to rising sea levels. The rate of increase is accelerating in many locations along the East and Gulf coasts.
Snowpack: Snowpack in early spring has decreased at over 90 percent of measurement sites in the western United States between 1955 and 2016.
Heat-Related Deaths: Over 9,000 Americans were reported to have died from heat-related illnesses since 1979. However, data variability makes it difficult to discern long-term trends.
Marine Species Distribution: The average center of biomass for 105 marine fish and invertebrate species along U.S. coasts shifted northward by about 10 miles between 1982 and 2015. These species also moved an average of 20 feet deeper.
EPA's Climate Change Indicators
The EPA's indicators serve as a resource for communication, environmental assessment, and informed decision-making.
Indicators are updated annually at www.epa.gov/climate-indicators.
A PDF of the 2016 report is available online, and printed copies can be requested via email.
Temperature Trends
Annual average temperatures in the contiguous 48 states have been tracked from 1901 to 2015, using the 1901–2000 average as a baseline.
Categories of Indicators
Greenhouse Gases
U.S. Greenhouse Gas Emissions
Global Greenhouse Gas Emissions
Atmospheric Concentrations of Greenhouse Gases
Climate Forcing
Weather and Climate
U.S. and Global Temperature
High and Low Temperatures
U.S. and Global Precipitation
Heavy Precipitation
Tropical Cyclone Activity
River Flooding
Drought
A Closer Look: Temperature and Drought in the Southwest
Oceans
Ocean Heat
Sea Surface Temperature
Sea Level
A Closer Look: Land Loss Along the Atlantic Coast
Coastal Flooding
Ocean Acidity
Snow and Ice
Arctic Sea Ice
Antarctic Sea Ice
Glaciers
Lake Ice
Community Connection: Ice Breakup in Two Alaskan Rivers
Snowfall
Snow Cover
Snowpack
Health and Society
Heat-Related Deaths
Heat-Related Illnesses
Heating and Cooling Degree Days
Lyme Disease
West Nile Virus
Length of Growing Season
Ragweed Pollen Season
Ecosystems
Wildfires
Streamflow
Stream Temperature
Tribal Connection: Trends in Stream Temperature in the Snake River
Great Lakes Water Levels and Temperatures
Bird Wintering Ranges
Marine Species Distribution
Leaf and Bloom Dates
Community Connection: Cherry Blossom Bloom Dates in Washington, D.C.
About the Indicators
EPA presents 37 indicators and five features, organized into six chapters.
Each indicator includes easy-to-understand graphs or maps, background information, key points, data source descriptions, transparent technical support documentation, and web links to figures and data files.
Climate Change Indicators and Health
The 2016 Indicators report includes a feature on how climate change can affect human health.
A symbol is used to highlight climate/health interactions throughout the printed edition.
Interactive Maps
Some indicators feature interactive maps online.
For example, the sea level map can be clicked to show trends at specific locations.