The historic heat waves that roasted the United States and Europe over the summer may have subsided. But a record-breaking marine heat wave is gripping large swaths of the North Atlantic and North Pacific oceans.
The big picture: This has implications for marine species and extreme weather events, including hurricanes, as climate change exacerbates the problem. NOAA scientists warn that it shows no signs of an immediate decline.
Driving the news: “Climate change is making every marine heatwave warmer than the last,” researcher Dillon Amaya, who studies marine heatwaves at NOAA’s Physical Sciences Laboratory, told Axios.
- “Climate change is increasing the average temperature of the ocean (i.e. global warming),” Amaya says. “Marine heat waves are following this upward trend and warming accordingly.”
By the numbers: “The North Atlantic is currently something like four degrees Celsius warmer than normal, or at least parts of it are. And you end up seeing similar numbers for the North Pacific as well, it’s about four degrees Celsius warmer than normal,” Amaya said. .
State of play: Heat waves in the North Pacific and North Atlantic have been going on for about three months. “For these parts of the world, these temperatures are unprecedented,” Amaya said.
- Vincent Saba, a fisheries biologist at NOAA’s Northeast Fisheries Science Center, notes that it has “warmed faster on the Northeast Shelf of the United States than any other region of the country in the past 15 years” .
- Fish biomass was still relatively stable, but scientists had observed changes in marine species in the northwest Atlantic, Saba said in a phone interview last week.
- In the Pacific Ocean, there is a La Niña weather event for the third consecutive year. This may lead to warmer than normal conditions in the northeast Pacific, Amaya said.
To note : Global warming is not the only impact of climate change.
- “We are also talking about an increased concentration of carbon dioxide in the water, which makes the waters more acidic,” says Saba.
- “It can impact species on the shelf like lobster, high value sea scallops. We still don’t know what those impacts are.”
Threat level: “With climate change, some marine species will fare better than others,” says Saba.
- Research suggests that warmer water species stay longer in the northeastern United States, while North Atlantic right whales feed in different waters as they follow their plankton prey, which have moved, raising concerns about ship strikes and entanglement in fishing gear.
- It’s unclear if this is due to climate change or warming waters, per Saba.
- “We have seen major shifts in species distribution,” he says. “Warmer water species moving north and many cooler water species moving further north out of the system has kind of been the general trend.”
- Research by Saba and her colleagues found that warmer waters lead to the hatching of almost all female sea turtles – although projections indicate that the biggest long-term threats will be hatchling mortality as that nests and beaches are warming and that erosion due to sea level rise is destroying nests.
Enlarge: Bette Zirkelbach, director of Turtle Hospital in the Florida Keys, said that in addition to the newborn problem, she’s seen an increased prevalence of fibropapillomatosis (FP), a tumor-causing disease that primarily affects babies. green turtles.
- In the past 12 months, 70% of approximately 47 turtles admitted to hospital with PF have been diagnosed with internal tumors and had to be euthanized because there is currently no treatment for internal tumors, Zirkelbach said during of a telephone interview on Tuesday.
- “Warmer waters cause these tumors to grow,” she said.
Meanwhile, 20 Kemp’s Ridley sea turtles were taken to hospital from New England last year after the critically endangered animals stayed too long in Cape Cod Bay instead of leaving with the Gulf Stream.
- “Cold weather hits and they get trapped,” Zirkelbach said.
What to watch: The sea heatwave is not only a threat to animals. Models predict it could exacerbate the killer Hurricane Fiona if the storm continues to track north and enters the Northwest Atlantic later this week.
- If that happened, it would help Fiona maintain her tropical nature and intensity longer than if the sea heat wave weren’t there, Amaya notes. However, “strong winds and associated upper ocean mixing can help cool parts of the ocean that are really warm right now.”
The bottom line: To break the marine heat wave, “atmospheric winds must return to normal and the ocean would then need time (usually several months) to cool down without being pitted again,” says Amaya.
#Recordbreaking #marine #heatwave #North #Atlantic #threatens #marine #life