new normal

National drought

December 5, 2024 By EarthWise Leave a Comment

Climate change brings with it many kinds of extreme weather. It isn’t just higher temperatures. It is changing patterns of weather and weather events that are rare or even unprecedented.

Late October saw drought conditions throughout almost the entire United States. Only Alaska and Kentucky did not have at least moderate drought conditions.

The previous four months were consistently warmer than normal over a large area of the country. When that period started, about a quarter of the country was at least somewhat dry, but in late October, 87% of the country was dry.

Droughts in many parts of the U.S. and in places around the world are becoming more frequent, longer in duration, and more severe.

Residents of New York City were urged to start conserving water. This October was the driest October since record keeping began in 1869. The upstate reservoirs that supply New York’s water were below two-thirds full. They are normally more than three-quarters full in the fall.

Even the Southeast, which received huge amounts of rain from Hurricane Helene, is experiencing drought. Not much rain had fallen since that storm and warmer temperatures mean more evaporation and drier soils.

Drought is not just a lack of precipitation. Drought conditions are driven by abnormally high temperatures that remove moisture from the atmosphere and the ground.

Whether widespread drought conditions will persist is unknown. If a predicted La Niña condition develops in the tropical Pacific, drought conditions in the southern half of the country could get worse, but the Northeast could see lots of rain and snow.

To have nearly the entire country experiencing drought conditions is pretty rare. But unusual weather is becoming the new normal.

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In a Record, All but Two U.S. States Are in Drought

Photo, posted May 21, 2024, courtesy of Adam Bartlett via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

2022 Temperature Report | Earth Wise

February 8, 2023 By EarthWise Leave a Comment

The average surface temperature for the Earth in 2022 tied with 2015 as the fifth warmest on record. The warming trend for the planet continued with global temperatures 1.6 degrees Fahrenheit above the average baseline for 1951-1980 that NASA uses for its studies. Compared with the late 19th century average used in setting climate goals, global temperatures are up about 1.1 degrees Celsius, or 2 degrees Fahrenheit.

Overall, the past nine years have been the warmest since modern recordkeeping began in 1880. The rising temperatures have moved in concert with rising levels of greenhouse gases entering the atmosphere from human activity. Many factors can affect the average temperature in any given year including El Nino and La Nina conditions in the Pacific. But the longer-term trend is quite clear. Global temperatures continue to rise.

Greenhouse gas emissions have reached all-time high levels despite increasing efforts to reduce them. There was a real drop in levels in 2020 due to reduced activity during COVID-19 lockdowns, but they rebounded soon thereafter.

The Arctic region continues to experience the strongest warming trends, as much as four times the global average. Arctic warming has a major impact on weather at lower latitudes as it changes the behavior of the jet stream as well as affecting ocean currents and water temperatures.

As global temperatures continue to rise, rainfall and tropical storms have become more intense, droughts have become more severe, and ocean storm surges have had increasing impact. From torrential monsoons in Asia to megadroughts in the U.S. Southwest, extreme weather has become the new normal.

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NASA Says 2022 Fifth Warmest Year on Record, Warming Trend Continues

Photo, posted June 20, 2020, courtesy of Daxis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The New Normal Weather

March 13, 2019 By EarthWise Leave a Comment

We often hear about how the weather is getting stranger all the time, but do most of us really think so? What kinds of weather do we really find remarkable and has that been changing?

A study led by the University of California, Davis used some very modern tools to examine the question of what people might consider to be “normal” weather. To reach their conclusions, they quantified the timeless pastime of talking about the weather by analyzing Twitter posts. They sampled over 2 billion geolocated tweets to determine what kind of events generated the most posts about the weather.

Unsurprisingly, they found that people most often tweet when temperatures are unusual for a particular place and time of year. However, if the same weather persisted year after year, it generated less comment on Twitter, indicating that people began to view it as normal in a relatively short amount of time.

The study indicates that people have short memories when it comes to what they consider normal weather. On average, most people base their idea of normal weather on what has happened in just the past two up to maybe eight years. This disconnect with the historical climate record may obscure the public’s perception of climate change.

After repeat exposures to historically-extreme temperatures, people talk less about the weather, even though particularly hot or cold weather conditions make them unhappy and grumpy. Even though we are experiencing conditions that are historically extreme, we might not consider them to be particularly unusual if we tend to forget what happened more than a few years ago. Things may be getting worse, but they apparently are just the new normal.

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Tweets tell scientists how quickly we normalize unusual weather

Photo, posted March 11, 2013, courtesy of Adedotun Ajibade via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.