World's Oceans Are Gasping for Breath
A decrease in dissolved oxygen due to warming could be a major threat to marine life. Continue reading →
Here's yet another alarming consequence of human-driven climate change. We're rapidly smothering the ocean, and the creatures that live in it.
A new study in Global Biogeochemical Cycles, a journal published by the American Geological Union, concludes that a reduction in amount of oxygen dissolved in the world's oceans will be evident across large regions between 2030 and 2040, and already is evident in some places.
The study was led by scientists from the National Center for Atmospheric Research (NCAR).
"Loss of oxygen in the ocean is one of the serious side effects of a warming atmosphere, and a major threat to marine life," NCAR scientist Matthew Long, lead author of the study, said in a press release.
"Since oxygen concentrations in the ocean naturally vary depending on variations in winds and temperature at the surface, it's been challenging to attribute any deoxygenation to climate change. This new study tells us when we can expect the impact from climate change to overwhelm the natural variability."
According to the study, which was based upon computer modeling, the decrease in dissolved oxygen already is evident in the southern Indian Ocean and parts of the eastern tropical Pacific and Atlantic basins.
The ocean gets its oxygen supply from the surface, both from the atmosphere and from phytoplankton, which release oxygen into the water. But as an article from Yale's Environment 360 explains, as ocean temperatures warm, surface seawater becomes lighter, due to the influx of freshwater from melting glaciers, icebergs and ice sheets, and from expansion. That means that surface water will be less likely to sink into the deep ocean, which will keep those waters from being oxygenated.
A decrease in dissolved oxygen - which scientists call hypnoxia – can cause vast dead zones in the ocean, which are virtually devoid of marine life.
The Indian Ocean, seen from the International Space Station, already is experiencing a loss of dissolved oxygen that could prove devastating for marine life.
The National Oceanic and Atmospheric Administration (NOAA) is celebrating "30 Days of the Ocean" in the month of June, and in honor of the organization's hat-tip to life undersea, we take a look, this final June weekend, at some of the organization's captivating marine life snapshots. Here, the eyes of a queen conch (
) peek out from under its shell in La Parguera, Puerto Rico.
Kelp and sardines, just doing what they do, off Anacapa Island, Channel Islands National Marine Sanctuary.
This school of permits contains 60-80 individuals, each more than a foot long. The school was observed in the Dry Tortugas, Florida.
A Caribbean spiny lobster strolls on the sea floor. This photo was shot during a 2010 NOAA expedition in the U.S. Virgin Islands to map underwater habitats and the marine life they support.
DNA testing confirmed that the eggs pictured here were those of a loggerhead turtle, a marine reptile species listed as threatened under the Endangered Species Act. The testing was done by NOAA's Center for Coastal Environmental Health and Biomolecular Research, in Charleston, S.C., the only lab in the country dedicated to forensic analysis of marine species.
This manta ray coasts over a reef, in the process inviting much smaller fish to clean parasites and other debris off of it. Manta Rays are the largest type of ray in the ocean.
Make way for the balloonfish, also known as a porcupine or spiny puffer fish. As its name suggests, it will swell up like a balloon when attacked.
Here we see a close-up of brain coral in the Dry Tortugas, Florida.
Off the California coast, a group of elephant seals sleeps in the sun on a sand dune on Active Point, San Miguel Island, part of the Channel Islands National Marine Sanctuary.
With its distinctive reddish and white stripes, its gracefully flowing fins, and its menacing spine, not many fish can embody the beauty, mystery, and danger of the ocean quite like the lionfish. Although it's native to the Indo-Pacific region, lionfish were introduced to the Atlantic and are now found along the U.S. coast, from North Carolina to Florida, and in the Bahamas and Caribbean. The lionfish spells trouble for the balance of ecosystems and fisheries it invades, as it can out-compete native species for food and space. It lacks predators, has a voracious appetite, reproduces quicly, and is spreading fast.