With global climate change, ocean warming is accelerating and sea levels are rising faster, warns a new report by the UN Intergovernmental Panel on Climate Change.
The report is a synthesis of the most up-to-date climate science for the oceans and ice, and it presents a terrific reality: ocean surface temperatures have been warming ever since 1970 and have warmed twice as fast over the last 25 years.
Sea levels are also rising at an increasing rate "due to increasing rates of ice loss from the Greenland and Antarctic ice fields," the report said.
"To me, this is the complete picture, which is kind of surprising and, frankly, disturbing," says Ko Barrett, Vice-Chair of the UN Group and Deputy Assistant Research Administrator at the National Oceanic and Atmospheric Administration in USA "This is somehow a water report. Water is the lifeblood of the planet. "
A report also discusses a relatively new phenomenon in the oceans: sea heat waves.
"It's remarkable that before 201
Elaine Thompson / AP
Abnormally hot water affects animals that live off the coast of Maine, including lobsters and other creatures that are critical to the local fisheries economy. Moreover, it quickly became clear that the state was not alone.
"Subsequently, these types of heat waves have erupted all over the ocean," says Pershing. "We actually had three big heat waves in the Gulf of Maine – 2012, 2016 and 2018 – and now we're looking at recurring heat waves in the North Pacific; Australia has had some recurring heat waves. So it's really becoming part of the conversation in oceanography. "
" This is some emerging problem, "Barrett says. "The report finds that these heat waves have been doubling in frequency since the 1980s and are increasing in intensity."
This is great work for coastal communities whose economies rely on fish and other seafood. Sea heat waves in recent years have driven a cascade of changes in marine life off the Pacific Northwest, which in turn has led to catastrophic seasons for commercial fishermen.
"We have had two federally declared fishery disaster seasons in 2016 and 2017," says Noah Oppenheim, executive director of the Pacific Federation of Fisheries Associations. "The distress seasons we have experienced have put many fishermen on the edge. "
Abnormally hot water kept algae flowering, polluting the West Coast Dungeness crab fishery, shutting it down for months. Meanwhile, the so-called Hot Water Ash offshore was associated with drought, which cut through the land. the village maggot increases the risk of fires and strained inland water resources.
"Certainly this is a phenomenon that we need to pay more attention to because I think there are links between sea heat waves and, say, weather, because it affects even the interior of the continents, "says Barrett.
The rise in water temperature in the Gulf of Mexico has also affected the weather in this region. When sea surface temperatures are unusually high, this helps to cause larger, wetter tropical storms. For example, Hurricane Harvey and the Tropical Depression Imelda have entered the interior and dumped incredible amounts of rain on Texas over the past two years.
The UN Group report proposes a number of actions that local, state and national leaders can take to delay the warming and warming of the ocean. and adapt to its impact. First and foremost, the authors have been reinforcing what has been known for decades: greenhouse gas emissions from fossil fuels are the main driver of change in the oceans, and the global economy must undergo a dramatic transformation to reduce these emissions.  The report notes that the oceans become more acidic, which can lead to the mass extinction of marine organisms, especially animals with shells such as oysters and mussels.
However, the report also notes that if greenhouse gas emissions are immediately and drastically curtailed, some of the effects of ocean acidification could be avoided this century.
Some marine impacts of climate change will develop in the coming years, no matter what. Accelerating sea-level rise, for example, will threaten billions of people and pose an existential threat to millions living in coastal communities that are susceptible to flooding and relying on fishing.
"Even if we are reducing our carbon footprint right now, we are still looking at a change of 20 to 30 years," explains Pershing. ]