Scientists stunned by Antarctic rainfall and a melt area bigger than Texas

Scientists stunned by Antarctic rainfall and a melt area bigger than Texas

SOURCE: Washington Post

DATE: June 15, 2017

SNIP: Scientists have documented a recent, massive melt event on the surface of highly vulnerable West Antarctica that, they fear, could be a harbinger of future events as the planet continues to warm.

In the Antarctic summer of 2016, the surface of the Ross Ice Shelf, the largest floating ice platform on Earth, developed a sheet of meltwater that lasted for as long as 15 days in some places. The total area affected by melt was 300,000 square miles, or larger than the state of Texas, the scientists report.

That’s bad news because surface melting could work hand in hand with an already documented trend of ocean-driven melting to compromise West Antarctica, which contains over 10 feet of potential sea level rise.

Geoscientific evidence for subglacial lakes

Geoscientific evidence for subglacial lakes

SOURCE: Alfred Wegener Institute

DATE: June 1, 2017

SNIP: During the last glacial period – when the ice in the Antarctic was far thicker and extended further offshore than it does today – it has been speculated that subglacial lakes existed beneath it. An international team of researchers has now successfully sampled the metre-thick sediment layers left behind by these lakes contemporary on the seafloor.

Hundreds of subglacial lakes currently exist beneath the Antarctic Ice Sheet, with Lake Vostok being the largest and best known. The challenges involved in exploring these lake systems, which have remained enclosed for thousands of years, are enormous.

Satellite-monitoring shows that the movement of water from one lake to another can cause glaciers draining the Antarctic Ice Sheet to move more quickly. “This aspect needs to be taken into account in models designed to make predictions on the future behaviour and dynamics of ice masses, and with them, the degree to which the sea level will rise,” explains AWI marine geologist Kuhn. According to a second study, which Kuhn contributed to and was published in Nature Communications on 17 March 2017, he added: “We have every reason to believe that there are more subglacial lakes in the Antarctic – and more so in the last glacial period – than has been previously assumed. In addition, icecaps like those on the sub-Antarctic island South Georgia and ice sheets reacted much more sensitively and rapidly to climate changes than previously assumed.

Second Biggest Jump in Annual CO2 Levels Reported as Trump Leaves Paris Climate Agreement

Second Biggest Jump in Annual CO2 Levels Reported as Trump Leaves Paris Climate Agreement

SOURCE: Inside Climate News

DATE: June 1, 2017

SNIP: As President Donald Trump prepared to pull the United States out of the global Paris climate agreement this week, scientists at NOAA reported that 2016 had recorded the second-biggest jump in atmospheric carbon dioxide on record.

Last year’s increase in the atmospheric CO2 concentration was nearly double the average pace since detailed measurements started in 1979.

Concentrations of other greenhouse gases, including methane and nitrous oxide, also increased last year, according to the National Oceanic and Atmospheric Administration’s latest update to its greenhouse gas index. The heating effect of all combined greenhouses gases in the atmosphere increased by 2.5 percent in 2016, according to the index.

Acidified ocean water widespread along North American West Coast

Acidified ocean water widespread along North American West Coast

SOURCE: Oregon State University News and Research Communications

DATE: May 31, 2017

SNIP: A three-year survey of the California Current System along the West Coast of the United States found persistent, highly acidified water throughout this ecologically critical nearshore habitat, with “hotspots” of pH measurements as low as any oceanic surface waters in the world.

The researchers say that conditions will continue to worsen because the atmospheric carbon dioxide primarily to blame for this increase in acidification has been rising substantially in recent years.

A team of researchers developed a network of sensors to measure ocean acidification over a three-year period along more than 600 miles of the West Coast. The team observed near-shore pH levels that fell well below the global mean pH of 8.1 for the surface ocean, and reached as low as 7.4 at the most acidified sites, which is among the lowest recorded values ever observed in surface waters.

The Larsen C Iceberg Is on the Brink of Breaking Off

The Larsen C Iceberg Is on the Brink of Breaking Off

SOURCE: Climate Central

DATE: May 31, 2017

SNIP: The saga of the Larsen C crack is about reach its stunning conclusion. Scientists have watched a rift grow along one of Antarctica’s ice shelves for years. Now it’s in the final days of cutting off a piece of ice that will be one of the largest icebergs ever recorded.

The crack has spread 17 miles over the past six days, marking the biggest leap since January. It’s also turned toward where the ice shelf ends and is within eight miles of making a clean break. There’s not much standing in its way either.

“The rift has now fully breached the zone of soft ‘suture’ ice originating at the Cole Peninsula and there appears to be very little to prevent the iceberg from breaking away completely,” scientists monitoring the ice with Project MIDAS wrote on their blog.

The breakup is sure to be a spectacle both awe-inducing and horrifying. The iceberg on the verge of splitting off is estimated to be the size of Delaware, covering an area of 1,930 square miles.

Scientists warn US coral reefs are on course to disappear within decades

Scientists warn US coral reefs are on course to disappear within decades

SOURCE: The Guardian

DATE: May 30, 2017

SNIP: Some of America’s most protected corals have been blighted by bleaching, with scientists warning that US reefs are on course to largely disappear within just a few decades because of global warming.

New research has shown that strict conservation measures in Hawaii have not spared corals from a warming ocean in one of its most prized bays, with the National Oceanic and Atmospheric Administration predicting yet more bleaching is likely off Hawaii and Florida this summer.

“As scientists we are breathlessly trying to catch up,” said Cobb [Kim Cobb, an oceanographer at Georgia Tech]. “Things started to run away from us around 10 years ago but we were perhaps a little naive in not realizing that.”

“This is another data point on the staggering breadth of damage across the global oceans. You can run but you can’t hide from the train wreck that is coming. The recent bleaching has been a brush with death and shows that this fatal stress is upon us.”

Nitrous Oxide Poses Fresh Threat to the Arctic

Nitrous Oxide Poses Fresh Threat to the Arctic

SOURCE: Scientific American

DATE: May 30, 2017

SNIP: The thawing of the Arctic permafrost is releasing a potent greenhouse gas into the atmosphere that has rarely been considered as a threat despite its tremendous potential to drive global warming.

Nitrous oxide, or N2O, is more of a threat to the Arctic and global warming than previously believed, according to a study published yesterday in the journal Proceedings of the National Academy of Sciences. Currently, it’s not usually considered when researchers create models to predict the future warming of the region.

As the permafrost thaws, emissions of nitrous oxide increase, researchers found. That’s significant because naturally occurring nitrous oxide, which is locked inside the permafrost when it is frozen, is a potent greenhouse gas with 300 times the global warming potential of carbon dioxide.

Climate change could make cities 8C hotter – scientists

Climate change could make cities 8C hotter – scientists

SOURCE: The Guardian

DATE: May 29, 2017

SNIP: Under a dual onslaught of global warming and localised urban heating, some of the world’s cities may be as much as 8C (14.4F) warmer by 2100, researchers have warned.

Such a temperature spike would have dire consequences for the health of city-dwellers, rob companies and industries of able workers, and put pressure on already strained natural resources such as water.

The projection is based on the worst-case scenario assumption that emissions of greenhouse gases continue to rise throughout the 21st century.

The top quarter of most populated cities, in this scenario, could see temperatures rise 7C or more by century’s end, said a study in the journal Nature Climate Change.

For some nearly 5C of the total would be attributed to average global warming.

The rest would be due to the so-called “urban heat island” effect, which occurs when parks, dams and lakes, which have a cooling effect, are replaced by concrete and asphalt – making cities warmer than their surrounds, the researchers said.

Great Barrier Reef is damaged beyond repair and can no longer be saved, say scientists

Great Barrier Reef is damaged beyond repair and can no longer be saved, say scientists

SOURCE: The Telegraph (not usually a trustworthy source on climate change, so keep that in mind…)

DATE: May 29, 2017

SNIP: Scientists have concluded that the Great Barrier Reef can no longer be saved because it is so damaged.

The plight of the reef is partly due to the “extraordinary rapidity” of climate change, according to experts.

The reef has been severely damaged by the warming of the oceans, and around 95 per cent of it suffers from bleaching, according to scientists who surveyed it in 2016.

Experts have said the ecological function of the reef should be maintained as much as possible in coming years, but that the reef itself will not be saved in its current form.

Waves Rippled Through Greenland’s Ice. That’s Ominous

Waves Rippled Through Greenland’s Ice. That’s Ominous

SOURCE: Climate Central

DATE: May 26, 2017

SNIP: On its surface, the Greenland ice sheet is a vast expanse of seemingly immovable ice. But beneath the monotonous stretch of white, scientists have discovered evidence of waves rippling through one of its outlet glaciers and roiling its innards.

The waves, observed during the two most intense melt seasons on record, sent an unprecedented cascade of ice and water rushing into the sea and warping the very bedrock upon which the ice sits. As temperatures continue to rise, scientists fear that massive waves of ice could expedite Greenland’s melt even further, pushing sea levels higher.