It’s hot out there, and not just on land. Temperatures are skyrocketing both on land and at sea, with climate experts ringing alarm bells about unprecedented sea surface temperatures in the North Atlantic.
Yes, it’s July, and it’s normal for ocean waters to be a little warmer, but experts say, the extended extremely high ocean temperatures (“like bath water”) since May are drastically impacting sea ice levels, fisheries and coral.
“We are in uncharted territory and we can expect more records to fall as El Niño develops further and these impacts will extend into 2024,” World Meteorological Organization (WMO) director of climate services Christopher Hewitt said Monday. “This is worrying news for the planet.”
As CBS News reports, the National Oceanic and Atmospheric Administration (NOAA) in late June warned that half of the world’s oceans may experience marine heat wave conditions by September. Research scientist Dillon Amaya said that in the organization’s Physical Sciences Laboratory’s decades of measurement, such widespread high temperatures had never been seen.
“Normally, we might expect only about 10% of the world’s oceans to be ‘hot enough’ to be considered a marine heatwave, so it’s remarkable to reach 40% or 50%, even with long-term warming,” Amaya said.
Global sea temperatures in May and June were at record highs for the time of year. The temperatures also “much higher than anything the models predicted,” Dr. Michael Sparrow, head of the World Meteorological Organization’s world climate research department, said. Those high temperatures came, in part, before El Niño — which is associated with high ocean temperatures — even began, the European Union’s Copernicus Climate Change Service stressed in a July report.
With warmer temperatures, Antarctic sea ice “reached its lowest extent for June since satellite observations began, at 17% below average, breaking the previous June record by a substantial margin,” according to Copernicus. The region is usually thought of as being relatively stable when compared to the Arctic, Sparrow said.
High ocean temperatures are also causing coral bleaching, which can leave coral vulnerable to deadly diseases, experts warned. NOAA calls coral bleaching “one of the most visible and damaging marine ecological impacts of persistently rising ocean temperatures.”
Coral-based ecosystems act as nurseries for fish, which means that spiking ocean temperatures also impact fisheries. As water temperatures rise, marine life is moving toward the poles to stay cool, according to NOAA. This can mean fish are moving out of the range of fishers. Marine fisheries and seafood industries in the U.S. supported around 1.7 million jobs and $253 billion in sales in 2020, according to the agency.
Warmer ocean water can kill fish because it holds less oxygen than cooler water. In June, thousands of dead fish washed up along the Texas Gulf Coast because of a “low dissolved oxygen event.” Marine heat waves can also produce “hot spots” of harmful algae, which produces a toxin, domoic acid, that can accumulate in shellfish and make it dangerous to eat, according to NOAA.
According to ABC News, warmer ocean waters can contribute to more powerful tropical storms and impact marine life. In addition, a warmer atmosphere holds more moisture and can increase potential flooding events. Melting sea ice in the Arctic is also causing sea levels to rise, which is eroding coastlines.
Around 90% of global warming is occurring in the ocean, according to NASA. Scientists attribute the widespread heat of the global ocean waters to human-caused climate change. Scientists anticipate that the current high temperatures could increase in the coming weeks and set record-shattering numbers, which could spell disaster for coastal communities all over the world.
2023 is very likely to rank among the 10 warmest years on record, according to the National Centers for Environmental Information statistical analysis that was released in April. Should warmer ocean and air surface temperatures continue, 2023 could become the warmest year on record.