Hottest summer ever, NASA confirms
That was no surprise to the millions who experienced summer in the Northern Hemisphere, as the season just passed was the hottest on Earth since records began in 1880, according to NASA scientists.
The announcement by researchers at the Goddard Institute for Space Studies (GISS) in New York comes after consecutive months of record temperatures.
June, July, and August together were 0.41 °F (0.23 °C) warmer than recorded in NASA’s record books, and 2.1 °F (1.2 °C) warmer than the average summer between 1951 and 1980. August was 2.2°F (1.2°C) warmer than average.
It may come as no surprise that June, July and August all broke individual records for the hottest months yet. July beat its 2019 best by 0.24°C (0.43°F) and was the five hottest Julys on record in the past five years.
“The record temperatures in the summer of 2023 are not just a set of numbers, they lead to serious real-world consequences,” said NASA Administrator Bill Nelson. “From extreme temperatures in Arizona and across the country, to wildfires across Canada, and severe flooding in Europe and Asia, extreme weather is threatening lives and livelihoods around the world.”
GISTEMP, NASA’s temperature records, stem from surface air temperature data provided by tens of thousands of weather stations, and sea surface temperature data from ships and buoys. The raw data are analyzed taking into account the spacing of heat stations around the planet and the impact of urban heating.
“Exceptionally high sea surface temperatures, fueled in part by the return of El Niño, were largely responsible for the record summer warmth,” said Josh Willis, a climate scientist and oceanographer at NASA’s Jet Propulsion Laboratory in Southern California.
The Southern Hemisphere is now bracing for the El Niño Southern Oscillation (ENSO), with the World Meteorological Organization (WMO) predicting a 90% chance of a “moderately strong” El Niño arriving in spring 2023.
“The emergence of El Niño will significantly increase the likelihood of breaking temperature records and causing more extreme heat in many parts of the world and in the oceans,” WMO Secretary-General Professor Petteri Taalas said in a July statement.
The naturally occurring El Niño phenomenon, which typically occurs every two to seven years, stems from warm water rising to the surface in the central and eastern tropical Pacific Ocean. This has a significant impact on seasonal weather, leading to intensification of events such as heatwaves and floods.
As the United States heads into winter, this may be a temporary reprieve. Decades of data collected by NASA, the National Oceanic and Atmospheric Administration (NOAA), and others show that El Niño is being exacerbated by human-caused global warming.
“With rising temperatures and marine heat waves creeping up on us for decades, El Niño has pushed us to set all kinds of records,” Willis said. “The heat waves we are seeing now are longer, hotter and more extreme. The atmosphere can also hold more water now, and when it is hot and humid, it becomes more difficult for the human body to regulate its temperature.”
Earlier this year, the United Nations Intergovernmental Panel on Climate Change (IPCC) found that global temperature would likely increase by 2.7 degrees Fahrenheit (1.5 degrees Celsius) by the early 2030s. The timeline has been moved forward from previous projections set at 2050.
In addition to more records to break in the summer, this increase also brings with it many other serious issues including the increasing spread of new zoonoses, extinctions that are crippling international agreement on biodiversity targets, and food and water security concerns.
“Unfortunately, climate change is happening,” said Gavin Schmidt, a climate scientist and director of GISS. “The things we said would happen, will happen.” It will get worse if we continue to emit carbon dioxide and other greenhouse gases into our atmosphere.
Source: NASA
