Are Record-Breaking Heat Waves Here to Stay?


Scientists said that the past three days have been the hottest on Earth in modern history. An astonishing heat wave across the globe continues to break temperature records, from North America to Antarctica.

Forecasters are warning that Earth may be entering a period of unusual warmth for several years, due to two factors: the continued emission of heat-trapping gasses, mostly caused by humans’ burning of oil, coal, and gas; and the return of El Niño, which is a cyclical pattern of weather.

Already, there has been a dramatic increase. Researchers said that the planet has just experienced its hottest June on record, with deadly heatwaves scorching Texas and Mexico. While sea ice has reached record lows off the coasts of Antarctica this year.

The ocean in the North Atlantic has been scorching hot. In May, surface temperatures were 2.9 degrees Fahrenheit or 1.6 degrees Celsius warmer than usual for this time of the year. This was a record-breaking increase.

Even scientists who track climate change are disturbed by the sudden increase in temperature.

“It’s so far out of the line of what’s been observed that it’s hard to wrap your head around,” said Brian McNoldy, a senior research scientist at the University of Miami. “It doesn’t seem real.”

According to an analysis of the European Union’s Copernicus Climate Change Service, Tuesday was the hottest Earth day since 1940 when records were first kept. It is very likely that it was even hotter before then.

As this was an average figure, some parts of the world felt it more intensely. Scientists at the Lawrence Berkeley National Laboratory, California, say that climate change is responsible for the current heat wave in the Southern United States and Northern Mexico where the heat index is triple digits.

As humans continue to pump huge amounts of heat-trapping greenhouse gases into the air, the overall warming of our planet is “well in the realm of what the scientists projected would happen,” said Zeke Hausfather a climate researcher at Berkeley Earth and Stripe, a payments company.

Earth’s average temperature has increased by about 2 degrees Fahrenheit in the past century. It will continue to rise until humans stop all fossil fuel emissions and stop deforestation.

Other factors, layered over the human-caused heating, may have contributed to the dramatic increase in temperatures seen in recent months. El Niño and the Southern Oscillation is a cyclical phenomenon in the Pacific Ocean that causes fluctuations from year to year by shifting heat into and out of the deeper ocean layers. The global surface temperature tends to be lower during La Niña and higher during El Niño.

Dr. Hausfather explained that the transition from a La Niña of unusual length, lasting three years, which lowered temperatures, to a strong El Niño is a major reason for so many records being broken.

This could be a sign of even more heat to come. Many researchers do not expect the current El Niño to peak until December, and that global temperatures will continue to rise in the months following. Scientists say that next year’s temperatures could be higher than this year.

There may also be other dynamics at play. Since early March, the North Atlantic has experienced record temperatures. This was before El Niño conditions started. The Azores High, a subtropical system of high pressure that is known to have weakened winds over the ocean as well as reduced the amount of dust from the Sahara which would normally cool the ocean may be one factor.

McNoldy, a Dr. at the University of Miami, believes that these weather patterns may change in the coming weeks. He said that even then, temperatures would likely drop from record-breaking to extremely record-breaking.

Some meteorologists have increased their hurricane warnings this year due to the soaring temperatures. Forecasters from Colorado State University announced on Thursday that they expect an above-average Atlantic hurricane season with 18 tropical cyclones. This is a change in forecasts for a quieter-than-usual year. El Niño years are usually a time when hurricanes in the Atlantic are suppressed, but this may not be the case this year due to the unusually warm waters of the ocean, which could fuel storms.

Researchers have also suggested that efforts to clean up pollution caused by ships in the world could be causing temperatures to rise slightly. Sulfur dioxide tends to reflect sunlight, and thus cool the earth. The exact impact of sulfur dioxide is still under debate.

Gabriel Vecchi is a Princeton climate scientist. “There seems to be an unusual convergence of factors that are causing warming right now”, he said. “But all of this is happening in a climate where greenhouse gases have been rising for 150 years.” “That really loads the odds and makes it more likely that we will be pushed to record-breaking territory.”