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...
Ocean Warming Is Accelerating Faster Than Thought, New Research Finds

Ocean Warming Is Accelerating Faster Than Thought, New Research Finds

SOURCE: NY Times DATE: January 10, 2019 SNIP: Scientists say the world’s oceans are warming far more quickly than previously thought, a finding with dire implications for climate change because almost all the excess heat absorbed by the planet ends up stored in their waters. A new analysis, published Thursday in the journal Science, found that the oceans are heating up 40 percent faster on average than a United Nations panel estimated five years ago. The researchers also concluded that ocean temperatures have broken records for several straight years. “2018 is going to be the warmest year on record for the Earth’s oceans,” said Zeke Hausfather, an energy systems analyst at the independent climate research group Berkeley Earth and an author of the study. “As 2017 was the warmest year, and 2016 was the warmest year.” As the planet has warmed, the oceans have provided a critical buffer. They have slowed the effects of climate change by absorbing 93 percent of the heat trapped by the greenhouse gases humans pump into the atmosphere. Because they play such a critical role in global warming, oceans are one of the most important areas of research for climate scientists. Average ocean temperatures are also a consistent way to track the effects of greenhouse gas emissions because they are not influenced much by short-term weather patterns. As the oceans heat up, sea levels rise because warmer water takes up more space than colder water. In fact, most of the sea level rise observed to date is because of this warming effect, not melting ice...
Oceans Have Absorbed 60 Percent More Heat Than Previously Thought

Oceans Have Absorbed 60 Percent More Heat Than Previously Thought

SOURCE: Scripps Institution of Oceanography and Nature. DATE: November 1, 2018 UPDATE: November 13, 2018 Scientists acknowledge key errors in study of how fast the oceans are warming Scientists behind a major study that claimed the Earth’s oceans are warming faster than previously thought now say their work contained inadvertent errors that made their conclusions seem more certain than they actually are. Two weeks after the high-profile study was published in the journal Nature, its authors have submitted corrections to the publication. The Scripps Institution of Oceanography, home to several of the researchers involved, also noted the problems in the scientists’ work and corrected a news release on its website, which previously had asserted that the study detailed how the Earth’s oceans “have absorbed 60 percent more heat than previously thought.” “Unfortunately, we made mistakes here,” said Ralph Keeling, a climate scientist at Scripps, who was a co-author of the study. “I think the main lesson is that you work as fast as you can to fix mistakes when you find them.” ORIGINAL SNIP: For each of the past 25 years, oceans have absorbed an amount of heat energy that is 150 times the energy humans produce as electricity annually, according to a study led by researchers at Scripps Institution of Oceanography at the University of California San Diego and Princeton University. The strong ocean warming the researchers found suggests that Earth is more sensitive to fossil-fuel emissions than previously thought. Study lead author Laure Resplandy, a Princeton assistant professor of geosciences, said that this estimate is more than 60 percent higher than the figure in the most recent...
Watery heatwave cooks the Gulf of Maine

Watery heatwave cooks the Gulf of Maine

SOURCE: NASA DATE: September 12, 2018 SNIP: Most of us are familiar with heat waves on land, but in a warming world, heat waves are starting to become common in the ocean, too. One basin in particular, the normally cool Gulf of Maine in the Northwest Atlantic Ocean, has seen several heat waves in recent years and has spent most of 2018 with unusually warm water temperatures. On August 8, 2018, scientists using satellite data and sea-based sensors measured the second warmest sea surface temperatures ever observed in the Gulf of Maine. Average water temperatures reached 20.52 degrees Celsius (68.93 degrees Fahrenheit) that day, just 0.03°C (0.05°F) below the record set in 2012. The map on this page shows sea surface temperature anomalies as compiled by NOAA’s Coral Reef Watch, which blends observations from the Suomi NPP, MTSAT, Meteosat, and GOES satellites and from computer models. Shades of red and blue indicate how much water temperatures were above or below the long-term average for the region. The map [on this post] shows conditions on August 8, the near-record setting day. The heatwave of 2018 fits with a much longer trend in the region, which is among the fastest-warming parts of the global ocean. In the past three decades, the Gulf of Maine has warmed by 0.06°C (0.11°F) per year, three times faster than the global average. Over the past 15 years, the basin has warmed at seven times the global average. The Gulf has warmed faster than 99 percent of the global ocean. “Climate change is likely contributing to the circulation changes through melting in Greenland and Arctic, as...
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...