Changes in climate are already negatively impacting the environment in the U.S., according to the third edition of the EPA report “Climate Change Indicators in the United States.”
The study pulls together observed data on environmental measures such as temperature, precipitation, ocean heat and acidity, the length of growing seasons, and others. Taken together, the data yields 30 indicators of how climate change affects environmental and human health in the U.S. and globally.
- Average temperatures have risen in the continental U.S. consistently since 1901, with an increased rate of warming over the last 30 years. Seven of the top 10 warmest years on record have occurred since 1998.
- Tropical storm activity in the Atlantic Ocean, the Caribbean, and the Gulf of Mexico has increased during the past 20 years.
- The highest sea level rise on the U.S. coastline occurred among the Mid-Atlantic coast and parts of the Gulf Coast. Some measuring stations registered increases of more than 8 inches in the sea level between 1960 and 2013.
- The rise in sea level is partially due to the loss of glacial ice, which has been melting at an accelerated rate over the last decade.
- Between 2000 and 2013, every part of the Southwest experienced higher average temperatures than the long-term average, which dates back to 1895.
- Water levels in most of the Great Lakes have declined in the last few decades.
The report also examines impacts on human health and society by incorporating indicators related to the incidence of Lyme disease, heat-related deaths, and pollen season. For example, unusually hot summer temperatures have become more common, leading to a higher risk of heat-related deaths and illness. The warmer temperatures and delayed fall frosts also allow ragweed plants to continue producing pollen later into the year, prolonging allergy season for affected people.