A level hotter than twenty years in the past – FOX23 Information

America’s new normal temperature is one degree hotter than it was two decades ago.

Scientists have long talked about climate change – hotter temperatures, changes in rain and snowfall, and more extreme weather – as the “new normal”. Data released Tuesday by the National Oceanic and Atmospheric Administration supports the stereotype.

The new normal in the United States is not only hotter, but also wetter in the east and center of the nation, and significantly drier in the west than it was a decade ago.

Meteorologists calculate climate normals based on data from 30 years in order to limit the random fluctuations in daily weather. It is a standard established by the World Meteorological Organization. Every 10 years, NOAA updates for the entire country, state, and city are performed normally – by year, month, and season.

For the entire nation, the normal annual temperature is now 53.3 degrees (11.8 degrees Celsius), based on weather station data from 1991 to 2020, almost half a degree warmer than a decade ago. Twenty years ago, the normal value was 52.3 degrees (11.3 degrees Celsius) based on data from 1971 through 2000. The average US temperature for the 20th century was 52.3 degrees (11.1 degrees Celsius).

The new US normal annual temperature is 1.7 degrees (0.9 degrees Celsius) hotter than the first calculated normal temperature for 1901-1930.

“Almost every place in the US warmed up from 1981-2010 to 1991-2020,” said Michael Palecki, project manager for normals at NOAA.

Fargo, North Dakota, where the new normal is one-tenth of a degree cooler than the old, is an exception, but more than 90% of the US now has warmer normal temperatures than 10 years ago, Palecki said.

In Chicago and Asheville, North Carolina, the new annual normal temperature rose 1.5 degrees in a decade. In Seattle, Atlanta, Boston, and Phoenix, normal annual temperatures have increased at least half a degree over the past decade.

Charlottesville, Virginia, had the largest increase in normal temperatures of 739 major weather stations. Other big changes were in California, Texas, Virginia, Indiana, Arizona, Oregon, Arkansas, Maryland, Florida, North Carolina, and Alaska.

New normals are warmer because fossil fuel burning makes the last decade “a much hotter time for much of the world than it did in decades,” said Natalie Mahowald, a climatologist at Cornell University.

For Phoenix, the biggest change from normal was rainfall. The normal annual rainfall for Phoenix fell 10% to 18.2 inches. Rainfall in Los Angeles decreased 4.6%.

At the same time, Asheville rainfall increased nearly 9% while New York City rainfall increased 6%. The normal value in Seattle is 5% more humid than before.

Climate researchers are split over how useful or misleading recalculated normals are.

Mahowald and University of Oklahoma Meteorology professor Jason Furtado said the update to normal calculations will help city and regional planners prepare for floods and drought, farmers decide what and when to plant, energy companies around to meet changing demands, and physicians to address public health problems arising from climate change.

However, Pennsylvania State University climatologist Michael Mann said he prefers a constant baseline like 1951-1980 used by NASA. Adjusting normally every 10 years “perverts the meaning of” normal “and” normalizes “climate change,” he said in an email.

North Carolina state climatologist Kathie Dello said, “It seems strange still calling them normal because 1991-2020 was far from normal in terms of climate.”


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The Associated Press Department of Health and Science is supported by the Department of Science Education of the Howard Hughes Medical Institute. The AP is solely responsible for all content.

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