Heat Check

That hot air that blanketed Europe has gone north, reaching the Arctic.  Sure enough, it has made a hot summer there much hotter.  This story is typical:

Greenland forest fires the largest ever monitored by satellite

"The heat wave that smashed high temperature records in five European countries a week ago is now over Greenland, accelerating the melting of the island’s ice sheet and causing massive ice loss in the Arctic.

More than 10 billion tons (11 billion U.S. tons) of ice was lost to the oceans by surface melt on Wednesday alone, creating a net mass ice loss of some 197 billion tons (217 billion U.S. tons) from Greenland in July, she said.

The current melting has been brought on by the arrival of the same warm air from North Africa and Spain that melted European cities and towns last week, setting national temperature records in Belgium, Germany, Luxembourg, the Netherlands and Britain.

Smoke from fires in Siberia has reached the US

In Russia, meanwhile, forest fires caused by hot, dry weather and spread by high winds are raging over nearly 30,000 square kilometers of territory in Siberia and the Russian Far East — an area the size of Belgium. The smoke from these fires, some of them in Arctic territory, is so heavy it can easily be seen in satellite photos...

Greenland has also been battling a slew of Arctic wildfires, something that Mottram said was uncommon in the past."

Another scientist on the scene spoke to NPR, and noted that melting in the center of the ice sheet hasn't happened since 2012, "which was a record amount year. But before that, we hadn't seen it happen since 1889. And by drilling into the ice sheet, we could look even earlier, and the last time it happened before that was 680 years earlier. So having these two large melt years happening quite close together certainly raises alarms about the loss that we're seeing. But it's really this year-to-year build-on of ice loss year after year that's particularly concerning. And unfortunately, that's headed into the ocean and showing up on our coastal shores."

Even a very small increase in sea levels adds to the dangers of hurricanes and other big storms, such as several that are currently brewing in the Atlantic and Pacific.  Greenland's ice specifically affects coastal flooding in Florida.

Elsewhere in the Arctic region, the state of Alaska is seeing sustained record heat:

The nation’s 49th state is warming faster than any other, having heated up more than 2 degrees Celsius (3.6 degrees Fahrenheit) over the past century — double the global average. And parts of the state, including its far northern reaches, have warmed even more rapidly in recent decades.

Temperatures have been above average across Alaska every day since April 25. None of the state’s nearly 300 weather stations have recorded a temperature below freezing since June 28 — the longest such streak in at least 100 years. On Independence Day, the temperature at Ted Stevens Anchorage International Airport hit 90 degrees for the first time on record."

But as profound as the dangers are of Arctic heating, sea levels around the world as well as ocean temperatures and salinity that affect major ocean currents, all feel much more impact from Antarctic melting, because there is so much more ice there, and it is on land.  When it melts into the sea, it increases water volume more directly. But any heating of ocean water--including from Arctic melt--increases melting in Antarctica:

"Like Greenland, the Antarctic ice sheet is losing ice and contributing to unabated global sea level rise. But there are worrying signs Antarctica is changing faster than expected and in places previously thought to be protected from rapid change. 

On the Antarctic Peninsula—the most northerly part of the Antarctic continent—air temperatures over the past century have risen faster than any other place in the Southern Hemisphere. Summer melting already happens on the Antarctic Peninsula between 25 and 80 days each year. The number of melt days will rise by at least 50 percent when global warming hits the soon-to-be-reached 1.5℃ limit set out in the Paris Agreement, with some predictions pointing to as much as a 150 percent increase in melt days.

But the main threat to the Antarctic ice sheet doesn't come from above. What threatens to truly transform this vast icy continent lies beneath, where warming ocean waters (and the vast heat carrying capacity of seawater) have the potential to melt ice at an unprecedented rate."

Meanwhile, records on the month of July are starting to come in, but even without adding the last several days, it has been the hottest July in recorded history in several New England cities, including Boston and Hartford, as well as the hottest of any month in more than 100 years.  Forecasts for August call for higher than average temperatures to continue in New England and the eastern states generally.  Of the lower 48, only the Midwest is predicted to have normal or slightly below average temps for the month.