Heatwave cooks mussels in their shells on California shore

Heatwave cooks mussels in their shells on California shore

SOURCE: The Guardian DATE: June 29, 2019 SNIP: In all her years working at Bodega Bay, the marine reserve research coordinator Jackie Sones had never seen anything like it: scores of dead mussels on the rocks, their shells gaping and scorched, their meats thoroughly cooked. A record-breaking June heatwave apparently caused the largest die-off of mussels in at least 15 years at Bodega Head, a small headland on the northern California bay. And Sones received reports from other researchers of similar mass mussel deaths at various beaches across roughly 140 miles (225km) of coastline. While the people who flocked to the Pacific to enjoy a rare 80F (27C) beach day soaked up the sun, so did the mussel beds—where the rock-bound mollusks could have been experiencing temperatures above 100F at low tide, literally roasting in their...
Climate Change Threat to Dolphins’ Survival

Climate Change Threat to Dolphins’ Survival

SOURCE: University of Zurich DATE: April 1, 2019 SNIP: An unprecedented marine heatwave had long-lasting negative impacts on both survival and birth rates on the iconic dolphin population in Shark Bay, Western Australia. Researchers at UZH have now documented that climate change may have more far-reaching consequences for the conservation of marine mammals than previously thought. Shark Bay in Western Australia in early 2011: A heatwave causes the water temperatures to rise to more than four degrees above the annual average. The extended period caused a substantial loss of seagrass, which drives the Shark Bay ecosystem, in this coastal area, a UNESCO world heritage site. Researchers from UZH have now investigated how this environmental damage has affected survival and reproduction of dolphins. They used long-term data on hundreds of animals collected over a ten-year period from 2007 to 2017. Their analyses revealed that the dolphins’ survival rate had fallen by 12 percent following the heatwave of 2011. Moreover, female dolphins were giving birth to fewer calves – a phenomenon that lasted at least until 2017. “The extent of the negative influence of the heatwave surprised us,” says Sonja Wild, former PhD candidate at the University of Leeds and first author of the study. “It is particularly unusual that the reproductive success of females appears to have not returned to normal levels, even after six...
Heatwaves sweeping oceans ‘like wildfires’, scientists reveal

Heatwaves sweeping oceans ‘like wildfires’, scientists reveal

SOURCE: The Guardian DATE: March 4, 2019 SNIP: The number of heatwaves affecting the planet’s oceans has increased sharply, scientists have revealed, killing swathes of sea-life like “wildfires that take out huge areas of forest”. Global warming is gradually increasing the average temperature of the oceans, but the new research is the first systematic global analysis of ocean heatwaves, when temperatures reach extremes for five days or more. The research found heatwaves are becoming more frequent, prolonged and severe, with the number of heatwave days tripling in the last couple of years studied. In the longer term, the number of heatwave days jumped by more than 50% in the 30 years to 2016, compared with the period of 1925 to 1954. As heatwaves have increased, kelp forests, seagrass meadows and coral reefs have been lost. These foundation species are critical to life in the ocean. They provide shelter and food to many others, but have been hit on coasts from California to Australia to...
Alien Waters: Neighboring Seas Are Flowing into a Warming Arctic Ocean

Alien Waters: Neighboring Seas Are Flowing into a Warming Arctic Ocean

SOURCE: Yale e360 DATE: May 10, 2018 SNIP: As the Arctic heats up faster than any other region on the planet, once-distinct boundaries between the frigid polar ocean and its warmer, neighboring oceans are beginning to blur, opening the gates to southern waters bearing foreign species, from phytoplankton to whales. The “Atlantification” and “Pacification” of the Arctic Ocean are now rapidly advancing. A new paper by University of Washington oceanographer Rebecca Woodgate, for example, finds that the volume of Pacific Ocean water flowing north into the Arctic Ocean through the Bering Strait surged up to 70 percent over the past decade and now equals 50 times the annual flow of the Mississippi River. And over on the Atlantic flank of the Arctic, another recent report concludes that the Arctic Ocean’s cold layering system that blocks Atlantic inflows is breaking down, allowing a deluge of warmer, denser water to flood into the Arctic Basin. “You have all this warm Pacific water coming into the Arctic and what is that going to mean?” says Robert Pickart, a physical oceanographer with the Woods Hole Oceanographic Institution in Massachusetts who studies Pacific Arctic circulation. “Not only is there more water going through, but there’s an increase in the amount of heat going through.” Adding more heat, he says, is “going to change the composition of the water and its likelihood to melt sea ice.” In addition, waters from the Atlantic that have long entered the Arctic Ocean and circled down deep are being driven higher onto shallow sea shelves north of Alaska by increasingly intense storms. (The Arctic’s extensive sea ice cover used...
In 2017, the oceans were by far the hottest ever recorded

In 2017, the oceans were by far the hottest ever recorded

SOURCE: The Guardian and Advances in Atmospheric Sciences DATE: January 26, 2018 SNIP: Among scientists who work on climate change, perhaps the most anticipated information each year is how much the Earth has warmed. That information can only come from the oceans, because almost all heat is stored there. If you want to understand global warming, you need to first understand ocean warming. This important ocean information was just released today by a world-class team of researchers from China. The researchers (Lijing Cheng and Jiang Zhu) found that the upper 2000 meters (more than 6000 feet) of ocean waters were far warmer in 2017 than the previous hottest year. We measure heat energy in Joules. It turns out that 2017 was a record-breaking year, 1.51 × 1022 Joules hotter than any other year. For comparison, the annual electrical generation in China is 600 times smaller than the heat increase in the ocean. The authors also calculated that all this heat resulted in approximately 2 mm rise in sea level (as water warms, it expands and so that ocean levels rise). Further consequences of this heating include declining oxygen levels in the oceans, bleaching of coral reefs, and melting of both sea ice and ice shelves (the latter of which which will also raise sea levels). We are observing these effects. Arctic ice is undergoing a long-term decline, and it’s possible the Arctic will become ice-free. Massive coral bleaching events have been recorded, particularly in the waters off of Australia. The point is, the effects of global warming aren’t just academic; they are...