U.S. Surface Temperatures

This indicator tracks observed changes in temperatures across the contiguous United States. Increasing U.S. temperatures reflect the overall warming trend in the climate system.
This indicator tracks observed changes in temperatures across the contiguous United States. Increasing U.S. temperatures reflect the overall warming trend in the climate system.

Average temperature in the U.S. in warming

Rising temperatures in the United States are indicative of warming in the global climate system. In the contiguous United States, temperatures during this century have been, on average, 1.5°F warmer than during the last century. Human activities have contributed to this increase in temperature through the addition of carbon dioxide and other heat-trapping
greenhouse gases Gases that absorb heat in the atmosphere near the Earth's surface, preventing it from escaping into space. If the atmospheric concentrations of these gases rise, the average temperature of the lower atmosphere will gradually increase, a phenomenon known as the greenhouse effect. Greenhouse gases include, for example, carbon dioxide, water vapor, and methane
into the atmosphere.
 The bars on the graph show the number of degrees by which the average U.S. temperature for each year differs from the average U.S. temperature during the last century.

About U.S. Surface Temperatures

These data were obtained from the National Oceanic and Atmospheric Administration (NOAA) nClimDiv dataset. The nClimDiv is based on daily data from the Global Historical Climatology Network (GHCN), which includes temperature and other climatic measurements from stations located around the world.
Why It's Important
This 
indicatorAn observation or calculation that allows scientists, analysts, decision makers, and others to track environmental trends, understand key factors that influence the environment, and identify effects on ecosystems and society.
can inform 
preparednessActons taken to build, apply, and sustain the capabilities necessary to prevent, protect against, and ameliorate negative effects.
decisions in a wide variety of sectors, such as energy production, agriculture, and human health.