Copernicus – July 2022 was the one of the three warmest Julys on record, marginally cooler than July 2019, and marginally warmer than July 2016. These margins are so small that a clear ranking is not possible.


In other words, the 2nd warmest July recorded.

Copernicus

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Mika Rantanen - New paper alert

I'm excited to announce that our open-access paper "The Arctic has warmed nearly four times faster than the globe since 1979" is now out: The Arctic has warmed nearly four times faster than the globe since 1979 | Communications Earth & Environment


a) Annual mean temperature anomalies in the Arctic (66.5∘–90∘N) (dark colours) and globally (light colours) during 1950–2021 derived from the various observational datasets.

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Human-caused climate change has been warming the Arctic nearly four times faster than the globe since 1979, researchers in Finland said in a new study released Thursday in the journal Communications Earth and Environment.

Why it matters: The study indicates that the polar region is warming faster than scientists previously estimated in other studies, which have previously said that the Arctic was warming either twice, more than twice or three times as fast as the planet on average.

The study also estimates that other parts of the Arctic — such as sea areas near Novaya Zemlya, Russia, and the Barents Sea north of Norway — are warming seven times as fast as the global average.

What they're saying: "We present evidence that during 1979–2021 the Arctic has been warming nearly four times as fast as the entire globe," the study stated.

"Thus, we caution that referring to Arctic warming as to being twice as fast as the global warming, as frequently stated in literature, is a clear underestimation of the situation during the last 43 years since the start of the satellite observations."

Thought bubble, via Axios' Andrew Freedman: Arctic climate change affects the entire world by altering the temperature difference between the tropics and the pole.

This can tip the scale toward more extreme weather events from a slowing summertime jet stream. The loss of sea ice induces a positive climate feedback that in turn warms the region even more rapidly, and can speed the melt of land-based ice sheets as well.

Scientists study the region closely because what happens in the Arctic does not stay in the Arctic. The region's permafrost stores vast amounts of greenhouse gases that, if released, would significantly speed and sharply escalate the amount of global warming. This is considered one of many tipping points in the climate system.

The big picture: Other scientists have observed record melt seasons from glaciers in parts of the Arctic this year, such as on the Norwegian archipelago of Svalbard.

Researchers have also observed peculiar and worrying melting patterns, like melt ponds and other surface water formations, on parts of the Greenland Ice Sheet in recent years.

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Antarctica’s ice shelves may be melting much faster than scientists previously anticipated — a phenomenon that could ultimately accelerate sea level rise, a new study has found.

Researchers at the California Institute of Technology and NASA’s Jet Propulsion Laboratory came to this conclusion by deploying a new model showing how dense, warm ocean water can get trapped along Antarctica’s icy coast and speed up melting.

Their model, detailed in Science Advances on Friday, homes in on a “narrow ocean current” adjacent to the coast that the authors described as “often-overlooked.”

Using the model, they simulated how rapidly flowing freshwater — melted from the ice shelves — can trap the warm ocean current at the base of the ice and thereby hasten the melting process.

“If this mechanism that we’ve been studying is active in the real world, it may mean that ice shelf melt rates are 20 to 40 percent higher than the predictions in global climate models,” co-author Andy Thompson, a professor of environmental science and engineering at Caltech, said in a statement.

Ice shelves are outcroppings of the Antarctic ice sheet, located where ice juts out from the land and floats on top of the ocean.

These shelves, which can be hundreds of meters thick, serve as a protective buffer for mainland ice — preventing the entire ice sheet from flowing into the ocean, according to the researchers.

As both the atmosphere and oceans warm due to a changing climate, the speed at which ice shelves are melting is increasing, the authors warned. Such conditions also therefore jeopardize their ability to block the flow of the ice sheet into the ocean, they added.

The study’s release comes amid a high-traffic week for research on the Earth’s poles.

On the opposite side of the planet, scientists showed on Thursday that the Arctic, too, is warming at a more rapid pace than previously assumed.

Yet another research team revealed on Wednesday how humans could potentially thwart the worst impacts of climate change on the East Antarctic Ice Sheet.

The Caltech-NASA researchers, however, focused their study on the West Antarctic Peninsula. This icy mass protrudes out of the higher polar latitudes and into lower, warmer altitudes, and has undergone the most dramatic changes due to climate change, they explained.

“There are aspects of the climate system that we are still discovering,” Thompson said, noting that improvements in modeling ocean, ice and atmosphere interactions have helped scientists make more accurate predictions, with less uncertainty.

“We may need to revisit some of the predictions of sea level rise in the next decades or century — that’s work that we’ll do going forward,” he added.


Fig. 8. Summary of mechanisms by which Antarctic Peninsula warming increases basal melt rates of WAIS.
(1) Multidecadal-scale warming trends over the Antarctic Peninsula have led to increased glacial runoff and freshening along the coast. (2) The influx of freshwater strengthens the westward-flowing, geostrophically balanced AACC, which (3) modifies the sea surface height and stratification in front of floating ice shelves. (4) The enhanced stratification traps more heat at depth and a larger proportion of warm water is directed into ice shelf cavities, (5) leading to enhanced basal melt rates.

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  • Dr. Robert Rohde - Every year a new layer of snow falls on Greenland & Antarctica. As the snow compacts into ice, tiny bubbles of air get trapped.


By carefully sampling the bubbles in old layers of ice, we can measure the past atmosphere.

That's how we know carbon dioxide has increased 50%. https://twitter.com/RARohde/status/1555470684192751617


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Extreme weather

  • This is the summer that climate change impacts are becoming overwhelmingly obvious and costly across much of Europe.


The big picture: Western Europe's fourth region-wide, fierce heat wave of the summer is well underway.

It's pushing temperatures into the triple digits Fahrenheit in Portugal, Spain, and France, and close to that level in the United Kingdom.

French firefighters are battling a nearly 20,000-acre blaze in the Gironde region that has forced thousands from their homes, while other fires burn elsewhere in the heat-affected regions.

That wildfire, burning in pine forests south of Bordeaux, has required the deployment of at least 1,000 firefighters, according to Reuters, with more resources on the way.

Temperatures in the region are forecast to exceed 100°F Thursday and Friday along with low relative humidity levels, making firefighting conditions extremely challenging.

Threat level: In the U.K., where temperatures are forecast to soar into the mid-to-upper 90s today through Sunday, the Met Office has hoisted an Amber "Extreme Heat Warning" through the period.

The fire danger in southeast England is forecast to reach its two highest categories, "very high" to "exceptional," with authorities warning that they may not be able to respond to every call.

During the record-breaking heat wave in July, fires swept through parts of London and London's mayor said it was the busiest day for fire crews since World War II.

Grasses in and around London are tinderbox dry, firefighters warn, and could ignite with the slightest spark, spreading rapidly in heat and drought conditions.

Context: Much of Europe is in the middle of an intense drought, which the heat will only worsen. French officials have called that country's drought, which has knocked some nuclear power plants that rely on river water to cool their reactors offline.

July was France's driest month on record dating back to 1959, and southern England is setting drought records as well.

In Germany, the Rhine River has hit such low levels that the viability of this crucial cargo artery, which carries commodities and energy supplies like coal and diesel fuel, is threatened.

This summer has also seen rapid and extensive melting of mountain glaciers across Europe, including the Swiss Alps.

According to the AP, in Valais, Switzerland, melting glaciers revealed parts of a plane that had crashed there long ago, as well as at least two skeletons in separate locations.

Of note: The heat and drought conditions are reducing crop productivity, cutting the harvest of key commodities at a time when food supplies are strained worldwide and prices are elevated due to Russia's unprovoked invasion of Ukraine.

Context: Heat waves are more likely to occur, more intense, and longer lasting due to human-caused climate change.

A study published following the extreme heat in England last month found that climate change made the event at least 10 times as likely than it would have been in preindustrial times.

It also found that the heat wave's average temperatures were at least 2°C (3.6°F) milder than they would have been in a world without today's high atmospheric concentrations of greenhouse gases, but observational data supports an even greater figure of a 4°C (7°F) difference. https://www.axios.com/2022/08/11/eur...climate-crisis