An intense marine heat wave has developed off the coast of the United States. West Coast, raising sea surface temperatures by more than 5 degrees Fahrenheit above normal.
The National Oceanic and Atmospheric Administration is tracking an area of warm water in the Pacific Ocean that formed and began to grow more than 1,000 miles offshore in May.
Changing wind patterns have altered the ocean’s circulation in recent weeks, pushing warm water to the coasts, according to Andrew Leising, a research oceanographer at NOAA’s Southwest Fisheries Science Center.
“There’s a big swath of water that’s over 4 degrees Celsius [7.2 degrees F] above normal, and it’s like a few hundred miles off coast, but that’s not that far,” he said. “That could reach the coast in the next week or so.”
The hotter-than-usual Pacific waters contribute to global sea surface temperatures that have repeatedly broken records over the last five months. Parts of the North Atlantic, Caribbean Sea, and Gulf of Mexico have been unusually warm, with temperatures nearing 100 degrees Fahrenheit off the coast of Florida several times last month.
The exceptional warmth of the world’s oceans has, in some ways, mirrored long and brutal heat waves that have swept across almost all continents, including South America, where winter is currently in full swing.
Ocean Health at Stake
Marine heat waves are not uncommon, but scientists closely monitor them because higher-than-normal ocean temperatures can fuel extreme weather, hasten the loss of polar ice, and exacerbate rising sea levels.
Researchers are also concerned about the health of the world’s oceans, which are critical to the planet’s ability to store heat. According to studies, the oceans have absorbed roughly 90% of the heat trapped on the planet due to greenhouse gas emissions since 1970.
The current marine heat wave in the Pacific has yet to be determined, but Leising believes it could end up being the second or third-most powerful heat wave on record for the region.
He also stated that the marine heat wave will most likely dissipate this fall, but some unknowns cloud the forecast. The main wild card, he said, is the potential influence of El Niño.
The return of El Nio conditions this year is expected to raise average air and sea temperatures worldwide, adding to the background warming caused by climate change.
According to Leising, it is unclear what effect El Nio will have on ocean temperatures for the rest of the year. However, in 2014, a massive and long-lasting marine heat wave known as “The Blob” simmered in the northeast Pacific during an El Nio event.
“So there is a hypothesis that El Niño may be able to affect atmospheric patterns in such a way that it could reinforce and sustain this current heat wave,” he said.
If warmer-than-usual waters persist, these conditions could also affect the migration patterns of sea life, including salmon and whales.
Such impacts could be widespread and long-lasting, Leising said.
Source: NBC News