Category Archives: Climate

Polar ice hits the lowest levels ever recorded


A very sobering report from NASA’s Earth Observatory:

In March 2017, Arctic sea ice reached a record-low maximum extent, according to scientists at NASA and the National Snow and Ice Data Center (NSIDC). In the same month, sea ice on the opposite side of the planet, around Antarctica, hit its lowest extent ever recorded at the end of the austral summer—a surprising turn of events after years of moderate sea ice expansion.

On February 13, 2017, the combined Arctic and Antarctic sea ice numbers were at their lowest point since satellites began to continuously measure sea ice in 1979. Total polar sea ice covered 16.21 million square kilometers (6.26 million square miles), which is 2 million square kilometers (790,000 square miles) less than the average global minimum extent for 1981–2010. That’s the equivalent to losing a chunk of sea ice larger than Mexico.

The line graphs above plot the monthly deviations and overall trends in polar sea ice from 1979 to 2017 as measured by satellites. The top line shows the Arctic; the middle shows Antarctica; and the third shows the global, combined total. The graphs depict how much the sea ice concentration moved above or below the long-term average. (They do not plot total sea ice concentration.)

Arctic and global sea ice totals have moved consistently downward over 38 years. Antarctic trends are more muddled, but they do not offset the great losses in the Arctic. The maps below give a closer look at the record lows that occurred at each pole this year.

The ice floating on top of the Arctic Ocean and its surrounding seas shrinks from mid-March until mid-September. As the Arctic temperatures drop in the autumn and winter, the ice cover grows again until it reaches its yearly maximum extent, typically in March. This winter, a combination of warmer-than-average temperatures, unfavorable winds, and a series of storms stunted sea ice growth in the Arctic.

The first map shows the concentration of Arctic sea ice on March 7, 2017, when it reached its maximum extent for the year. Opaque white areas indicate the greatest concentration, and dark blue areas are open water. All icy areas pictured here have an ice concentration of at least 15 percent (the minimum at which space-based measurements give a reliable measurement), and cover a total area that scientists refer to as the “ice extent.”

The maximum extent on March 7 was a record low, measuring 14.42 million square kilometers (5.57 million square miles). That’s 97,00 square kilometers (37,000 square miles) below the previous record low that occurred in 2015.

“We started from a low September minimum extent,” said Walt Meier, a sea ice scientist at NASA’s Goddard Space Flight Center. “There was a lot of open ocean water, and we saw periods of very slow ice growth in late October and into November because the water had a lot of accumulated heat that had to be dissipated before ice could grow. The ice formation got a late start and everything lagged behind—it was hard for the sea ice cover to catch up.”

This year’s record-low maximum will not necessarily lead to a new record-low minimum extent in summertime, since weather has a great impact on the melt season’s outcome, Meier said. “But it’s guaranteed to be below normal.”

Sea ice around Antarctica behaves in a similar manner, but with the calendar flipped—it usually reaches its maximum in September and its minimum in February. This year, Antarctic sea ice reached a record-low minimum on March 3. The second map shows the concentration of sea ice on that day.

The extent on March 3 measured 2.11 million square kilometers (815,000 square miles). That’s 184,000 square kilometers (71,000 square miles) below the previous record low in the satellite record, which occurred in 1997. This year’s low happened just two years after several monthly record-high extents in Antarctica and decades of moderate sea ice growth.

“There’s a lot of year-to-year variability in both Arctic and Antarctic sea ice, but overall, until last year, the trends in the Antarctic for every single month were toward more sea ice,” said Claire Parkinson, a senior sea ice researcher at NASA Goddard. “Last year was stunningly different, with prominent sea ice decreases in the Antarctic. To think that now the Antarctic sea ice extent is actually reaching a record minimum, that’s definitely of interest.”

Meier said it is too early to tell if this year marks a shift in the behavior of Antarctic sea ice.

“It is tempting to say that the record low we are seeing this year is global warming finally catching up with Antarctica,” Meier said. “However, this might just be an extreme case of pushing the envelope of year-to-year variability. We’ll need to have several more years of data to be able to say there has been a significant change in the trend.”

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DroughtWatch: A story told in four maps


In a departure from our usual weekly report from the United States Drought Monitor.

Click on any of the images to enlarge.

We begin with a look at current conditions in California, which are unchanged from last week:

Next up, how things looked four years ago this week:

We turn to a broader view, conditions in the 48 contiguous states this week:

And the same view, as it appeared four years ago:

Chart of the day: Republican science-blindness


From the Pew Research Center, which reports:

People’s level of science knowledge helps to a degree to explain their beliefs about climate change, but the relationship is complicated. While there are wide political divides in public views of the potential for harm from climate change. A majority of Democrats holding medium or high levels of science knowledge said it was “very likely” that climate change would lead to rising sea levels that erode beaches and shore lines, harm to animal wildlife and their habitats, damage to forests and plant life, storms that are more severe, and more droughts or water shortages. But there are no differences or only modest differences among Republicans holding high, medium and low science knowledge levels in their expectations of harms to the Earth’s ecosystems because of climate change.

Similarly, Democrats with high levels of knowledge about science, based on a nine-item index, almost all agree that climate change is mostly due to human activity (93%). By contrast, 49% of Democrats with low science knowledge think this is the case.

But among Republicans, there are no significant differences by science knowledge about the causes of climate change. Put another way, Republicans with high levels of science knowledge are no more likely than those with lower levels of knowledge to think climate change is mostly due to human activity.

This pattern did not occur on all judgments related to climate change, but to the extent that science knowledge influenced judgments, it did so among Democrats but not Republicans. (See our report “The Politics of Climate” for the results from statistical models of these patterns.)

Graphic Representation: Magical Misery Tour


With apologies to the Fab Four.

We begin with the Los Angeles Times, reading the fine print:

David Horsey: The joke is on voters who trusted Trump’s healthcare promises

While the Minneapolis Star Tribune looks at one of the impacts of EPA cuts:

Steve Sack: Clean water, the musical

The Miami Herald completes a slogan:

Jim Morin: Dirty work

A little sleight of hand from the Lexington Herald-Leader:

Joel Pett: Look! Up in the sky! It’s….

While the Atlanta Journal-Constitution covers the art of the steal:

Mike Luckovich: Let’s make a deal.

From the Kansas City Star, going down?:

Lee Judge: Establishing a trend

And from the Sacramento Bee, one character in 140:

Jack Ohman: Mad Men, the sequel…

The Arizona Republic draws a parallel:

Steve Benson: ‘I am not a. . .Dick’

From the Washington Post, the amen chours chimes in:

Tom Toles:  Does Donald Trump cry? Only like this. Sad!

From the Illinois Times, down at the heels:

Chris Britt: Trumpcare

The Buffalo News covers a case where ignorance isn’t bliss:

Adam Zyglis: Scott Pruitt remarks

The San Diego Union-Tribune sounds a similar note:

Steve Breen: New E.P.A. Chief Doubts CO2 Plays Big Part in Global Warming

From the Newark Star-Ledger, standard operating mode:

Drew Sheneman: Our paranoid President Trump

But paranoia may be reasonable, notes the Baton Rouge Advocate in the first of two spooky offerings:

Walt Handelsman: Turn off the TV

And the Tulsa World covers tools of the trade:

Bruce Plante: CIA spying tools

Finally, via the Washington Post, strike up the brand:

Ann Telnaes: The seal of approval

Global warming linked to massive coral reef dieoffs


Donald Trump and his crew of wreckers may believe climate change is a hoax, but nearly all of country’s scientists disagree huuugely.

So, too, does the American public, which is growing increasingly worried about what lies ahead, as new polling from Gallup reveals:

Yet mroof of the power of global warming to devastate vast ecosystems comes from new research from the Australian Research Council’s Centre of Excellence for Coral Reef Studies:

Coral researchers are remobilising to conduct aerial and underwater surveys along the Great Barrier Reef and elsewhere in Australia as coral bleaching reappears for the second year in a row. The decision coincides with the release today of a study [$32 to read] in the prestigious journal Nature warning the Reef’s resilience is rapidly waning.

Scientists and Reef managers from ten research institutions across Australia, representing the National Coral Bleaching Taskforce, have returned to the Reef only one year after scorching temperatures caused the worst coral bleaching event on record in 2016. Teams will spend the next few weeks in the air and underwater measuring the extent of the damage from this summer compared to last.

“We’re hoping that the next 2-3 weeks will cool off quickly, and this year’s bleaching won’t be anything like last year. The severity of the 2016 bleaching was off the chart,” explains lead author and Taskforce convener, Prof. Terry Hughes (ARC Centre of Excellence for Coral Reef Studies). “It was the third major bleaching to affect the Great Barrier Reef, following earlier heatwaves in 1998 and 2002. Now we’re gearing up to study a potential number four.”

Dead staghorn coral killed by bleaching on the northern Great Barrier Reef, November 2016. Credit: Greg Torda, ARC Centre of Excellence for Coral Reef Studies

“We have now assessed whether past exposure to bleaching in 1998 and 2002 made reefs any more tolerant in 2016. Sadly, we found no evidence that past bleaching makes the corals any tougher.”

While protecting reefs from fishing, and improving water quality is likely to help bleached reefs recover in the longer term, the study also revealed that it made no difference to the amount of bleaching during the extreme heatwave of 2016.

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DroughtWatch: California’s dry spell fades again


While all of California was still covered entirely by drought in September, only a fourth of the state is now involved in any level of official drought, and the Golden State is officially free of the two worst categories, while there was yet another small reduction in the third-worst category.

From the United States Drought Monitor:

Soil carbon found to pose even greater climate risk


New research reveals yet another alarming dimension of the climate change process, adding another powerful accelerant to the forces, many of them human in origin, driving the dramatic climate change now underway.

And this is yet another sign of the complexity of climate change, evidence that rising temperatures can trigger releases of still more forces that make the earth hotter as thresholds are crossed.

The irony is that the research comes from the U.S. Department of Energy,  a federal agency in a government headed by a climate change skeptic/denier [it depends on his whim of the moment]] who his appointed many other climate change deniers to high posts in his administration.

Under Obama, the department’s policy was clear, voiced by-then Secretary of Energy Ernest Moniz on the department website:

I’m not here to debate what’s not debatable.  I mean, the evidence is overwhelming.  The science is clear, certainly clear for the level that one needs for policymaking, in terms of the real and urgent threat of climate change.

Here’s his replacement during his confirmation hearings:

With Big Oil running the show, we suspect things will get much worse.

Meanwhile, let’s get grounded.

Steep rises in CO2 release follows soil warming in tests

From Lawrence Berkeley National Laboratory:

Soils could release much more CO2 than expected into the atmosphere as the climate warms, according to new research by scientists from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab).

Their findings are based on a field experiment that, for the first time, explored what happens to organic carbon trapped in soil when all soil layers are warmed, which in this case extend to a depth of 100 centimeters. The scientists discovered that warming both the surface and deeper soil layers at three experimental plots increased the plots’ annual release of CO2 by 34 to 37 percent over non-warmed soil. Much of the CO2 originated from deeper layers, indicating that deeper stores of carbon are more sensitive to warming than previously thought.

They report their work online March 9 in the journal Science [$30 for 24-hour access].

The results shed light on what is potentially a big source of uncertainty in climate projections. Soil organic carbon harbors three times as much carbon as Earth’s atmosphere. In addition, warming is expected to increase the rate at which microbes break down soil organic carbon, releasing more CO2 into the atmosphere and contributing to climate change.

But, until now, the majority of field-based soil warming experiments only focused on the top five to 20 centimeters of soil—which leaves a lot of carbon unaccounted for. Experts estimate soils below 20 centimeters in depth contain more than 50 percent of the planet’s stock of soil organic carbon. The big questions have been: to what extent do the deeper soil layers respond to warming? And what does this mean for the release of CO2 into the atmosphere?

“We found the response is quite significant,” says Caitlin Hicks Pries, a postdoctoral researcher in Berkeley Lab’s Climate and Ecosystem Sciences Division. She conducted the research with co-corresponding author Margaret Torn, and Christina Castahna and Rachel Porras, who are also Berkeley Lab scientists.

“If our findings are applied to soils around the globe that are similar to what we studied, meaning soils that are not frozen or saturated, our calculations suggest that by 2100 the warming of deeper soil layers could cause a release of carbon to the atmosphere at a rate that is significantly higher than today, perhaps even as high as 30 percent of today’s human-caused annual carbon emissions depending on the assumptions on which the estimate is based,” adds Hicks Pries.

The need to better understand the response of all soil depths to warming is underscored by projections that, over the next century, deeper soils will warm at roughly the same rate as surface soils and the air. In addition, Intergovernmental Panel on Climate Change simulations of global average soil temperature, using a “business-as-usual” scenario in which carbon emissions rise in the decades ahead, predict that soil will warm 4° Celsius by 2100.

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