Researchers from the Massachusetts Institute of Technology (MIT) suggest that much of the ocean surface will be bluer and greener due to the effect of rising global temperatures on phytoplankton, or microscopic marine algae that contain chlorophyll and need sunlight to live and grow.
The current outbreak, which began in October 2017 off southwest Florida, has been tied to a record 589 sea turtle deaths and 213 manatee deaths, the Herald-Tribune reported, citing figures from the Florida Fish and Wildlife Conservation Commission.
The research, published Tuesday in the journal Nature Communications, shows that from 1925-2016, the frequency of marine heatwaves increased on average by 34 percent and the length of each heatwave increased by 17 percent. In all, the number of marine heatwave days has increased 54 percent per year.
Scientists predict that so much pollution is pouring into the Gulf of Mexico this year that it is creating a larger-than-ever "dead zone" in which low to no oxygen can suffocate or kill fish and other marine life.
The Guardian reported that the National Oceanic and Atmospheric Administration (NOAA) is expected to announce this week the largest recorded hypoxic zone in the gulf, an oxygen-depleted swath that's even larger than the New Jersey-sized, 8,185 square-mile dead zone originally predicted for July.
Cyanobacteria bloom at Clear Lake, Lake County, California, resulted in oxygen depletion in the water and the subsequent mortality of multiple aquatic species, including carp, catfish, bluegill and crappie. Kirsten Macintyre, California Department of Fish and Wildlife
Associated Press reported that algal blooms have been detected in more than 40 of the California's bodies of water—the highest number in state history. The blue-green cyanobacterium's growth has been fueled by
record-breaking heat and a historic drought.
"Warm temperatures, increased nutrients, and low water flows aggravated by drought conditions and climate change are favoring toxin-producing cyanobacteria and algae; and a number of lakes, reservoirs and river systems are suffering blooms as a result," the California State Water Resources Control Board announced last month.
As the Sacrameto Bee described, this green muck has been spotted across the Golden State:
"Since July, officials have issued notices about potentially toxic blue-green algae in the Klamath River near the Oregon border; along an arm of the state's largest reservoir, Shasta Lake; and at Pyramid Lake in Los Angeles County. They've attributed the deaths of thousands of fish along a section of Clear Lake to toxic blooms. Blue-green algae also has formed in parts of the Sacramento-San Joaquin Delta, prompting health warnings about green, malodorous water in Discovery Bay and Stockton."
Beverley Anderson-Abbs, an environmental scientist with the State Water Board, told AccuWeather that blooms are usually seasonal, "However, these seasons have been getting longer over the past few years as winters have been relatively warm and water, especially in smaller lakes, has been warming earlier in the year and staying warm later."
"It is very possible that this could get worse in the future as temperatures continue to increase and the possibility of future droughts along with that," Anderson-Ebbs said.
Harmful algal blooms can produce toxins that can cause serious illness in people. Wade Hensley, a resident of Discovery Bay, California was hospitalized after microcystin poisoning, a byproduct of algae. According to NPR, his body went numb from the waist down.
The California Department of Public Health states that algae exposure can cause rashes, skin and eye irritation, allergic reactions and other health effects but at high levels, "exposure can result in serious illness or death."
Over on the East Coast, the Chesapeake Bay and waterways beyond are seeing bigger and longer lasting algal blooms. The Daily Press reported that a strain of algae called Alexandrium monilatum has spread from Virginia Beach to the James, York and Rappahannock rivers to the Eastern Shore—even as far north as the Potomac River.
The report states that this year's bloom is still going strong even though it usually disappears by early to mid-September. Researchers are now trying to understand if Alexandrium has an impact on marine life. Currently, it does not appear to be harmful to humans.
"So the guidance is you should probably avoid it," Virginia Department of Health's marine science supervisor Todd Egerton told the Daily Press. "But, for the most part, people haven't reported any issues with it."
A number of other drivers can spur algae growth, from warming water to excess nitrogen and phosphorus runoff. Algal blooms have been known to strip oxygen from the water, creating a "dead zone" that threatens fish and other marine life.
More than 20 states have seen occurrences of toxic algae blooms this summer, which have had far-reaching environmental and human health impacts across the country. The algae blooms can also be found around the world, in all climates from Greenland to Oman.