SOURCE: Inside Climate News

DATE: January 14, 2020

SNIP: The world’s oceans are warming at a rapidly increasing pace, new research shows, and the heat is having devastating effects on marine life and intensifying extreme weather.

Last year, the oceans were warmer than any time since measurements began over 60 years ago, according to a study published Monday in the journal Advances in Atmospheric Sciences.

While global surface temperature measurements go back farther in time, the measurement of ocean heat content is considered one of the most effective ways to show how fast Earth is warming because more than 90 percent of the heat trapped by greenhouse gases goes into the oceans.

The new study, the first to analyze ocean temperatures for 2019, was based on two independent data sets and used a new way of filling data gaps to measure ocean temperatures going back to the 1950s.

When the scientists compared ocean temperature data from the last three decades (1987-2019) to the three decades before that (1955-1986), they found the rate of warming had increased 450 percent, “reflecting a major increase in the rate of global climate change.”

Measured by a common energy unit used in physics, the oceans absorbed 228 sextillion joules of heat in the past 25 years. That’s equivalent to adding the energy of 3.6 billion Hiroshima-size atom bomb explosions to the oceans, said the study’s lead author, Lijing Cheng, with the International Center for Climate and Environmental Sciences at the Institute of Atmospheric Physics.

The warming of the oceans has widespread effects. It causes marine heat waves that kill fish and coral reefs, fuels hurricanes and coastal downpours, spawns harmful toxin-producing algal blooms and also contributes to heat waves on land, said study co-author Kevin Trenberth, with the National Center for Atmospheric Research.

The new evaluation of ocean heat content reinforces other recent signs of global warming. This past decade was the warmest on record since measurements started, and 2019 ended up the second-warmest year on record, though it was the warmest in the oceans.