NASA scientists have ranked 2017 as the second hottest year on record. The experts explained that in 2016, which holds the record as the hottest year in history, an El Niño event pushed temperatures higher. In 2017, however, temperatures broke records without the help of an El Niño.
March of 2017 was particularly exceptional. According to The National Oceanic and Atmospheric Administration (NOAA), “This marked the first time the monthly temperature departure from average surpassed 1.8°F (1.0°C) in the absence of an El Niño episode in the tropical Pacific Ocean.”
The El Niño Southern Oscillation (ENSO) cycle, which includes both El Nino and La Niña, causes global changes in temperatures and rainfall levels. El Niño results in warmer sea surface and atmospheric temperatures, while La Niña events leave the ocean and air colder than usual.
Greenhouse gas emissions are also affecting temperatures, and global warming has raised temperatures an average of 1 degree Celsius since the late 19th century. Since 2001, the planet has experienced 17 out of the 18 hottest years since record-keeping began in 1880.
Gavin A. Schmidt is the director of NASA’s Goddard Institute for Space Studies, which conducted the study.
“Individual ranking of years is not necessarily the most important thing,” Schmidt told the New York Times. “What we’re seeing is an increasing string of years of temperatures more than 1 degree above the pre-industrial era. And we’re not going to go back.”
Scientists are linking an abnormally warm February, in particular, to climate change. And the experts are saying that Earth’s changing environment is also to blame for the extent of the damaging hurricanes and wildfires that struck the United States in 2017.
“Despite colder than average temperatures in any one part of the world, temperatures over the planet as a whole continue the rapid warming trend we’ve seen over the last 40 years,” said Schmidt.
More details on the study by NASA can be found on their Global Climate Change website.