Ocean warming accelerated over past 100 years

TEXAS A&M (US) — Increased warming from changing ocean currents has accelerated over the past century and could ultimately affect climate patterns over much of the world, according to oceanographers.

A multinational team of researchers analyzed ocean temperature and current data since 1900. Their findings show that parts of the world’s oceans are warming at an accelerated rate, showing a global warming “signature” in the ocean. The warming trend in some parts of the oceans is twice as large as the global average, the researchers discovered.

“Certain parts of the oceans are getting warmer much faster than others,” says Benjamin Giese, professor of ooceanography at Texas A&M University, “and it shows that there are significant regional differences in warming. The difference is from 0.5 to more than 1.5 degrees, and while that may seem small, it is a large change compared with the historical data over the past 100 years.”


The rising temperatures are possibly attributed to ocean circulation changes, which are likely caused by changes in atmospheric circulation, especially in the winds over the oceans, says Ping Chang, professor of oceanography.

“If this trend continues, it could have a potential impact on the occurrence of extreme climate events, such as winter storms, in these regions because the atmospheric circulation is affected by sea-surface temperatures. These changes in ocean circulation could also have an impact on marine ecosystems.”

As reported in the journal Nature Climate Science, the most severely affected areas of rising ocean temperatures are off the coast of Australia, near the Philippines, the Gulf Stream from Florida to New England, the Brazil current, and the Kuroshio current, which is similar to the Gulf Stream but located in the Pacific Ocean near Japan.

Rising temperatures would probably not affect conditions of an El Niño or La Niña event.

“It is difficult to determine how these changes will affect global weather patterns,” Chang explains, “and it is more likely that regional climate extremes will be affected by these rising temperatures.”

The warming trend could pose problems for sensitive marine areas, Giese notes. “People in Australia are worried about it because it could have an impact on its Great Barrier Reef. Any rise in temperature might damage the sensitive ecosystems of the reef.”

At 1,800 miles long, the Great Barrier Reef is so large it can be seen from space.

Researchers from the Ocean University of China, National Oceanic and Atmospheric Administration, the University of Hawaii, the University of Colorado, the Woods Hole Oceanographic Institution, the University of Tokyo, the Ocean University of China, and scientists in Germany and Australia took part in the study.

The team’s work was funded by the China National Key Basic Research Project, the Australian Climate Change Science Program, the Southeast Australia Climate Initiative, the Japanese Ministry of Education, Culture, Sports, Science and Technology, NOAA, and the National Science Foundation.

More news from Texas A&M University: http://tamutimes.tamu.edu/