New research finds that “unusual changes in atmospheric jet stream circulation caused the exceptional surface melt of the Greenland Ice Sheet (GrIS) in summer 2012.”
Prof. Jennifer Francis tells me these changes are consistent with those caused by warming-driven “Arctic Amplification.” And that means GrIS may melt faster than climate models have projected.

Extent of surface melt over Greenland’s ice sheet on July 8, 2012 (left) and July 12, 2012. In just a few days, the melting had dramatically accelerated and an estimated 97 percent of the ice sheet surface had thawed. Credit: NASA.

Back in May, a study found that by 2025, there is a “50-50 chance” of this unprecedented ice melt happening annually simply based on the continued rapid warming of GrIS.

This new study, “Atmospheric and oceanic climate forcing of the exceptional Greenland ice sheet surface melt in summer 2012,” suggests this kind of melt may become commonplace even sooner.

As the news release explains, an international team used a computer model and satellite data “to confirm a record surface melting of the GrIS for at least the last 50 years – when on 11 July 2012, more than 90 percent of the ice-sheet surface melted. This far exceeded the previous surface melt extent record of 52 percent in 2010.” Weather station data “showed that several new high Greenland temperature records were set in summer 2012.”

The research “clearly demonstrates that the record surface melting of the GrIS was mainly caused by highly unusual atmospheric circulation and jet stream changes, which were also responsible for last summer’s unusually wet weather in England.”

What were these changes? Professor Edward Hanna from the University of Sheffield’s Department of Geography explains:

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A NASA science team has observed “amazing and potentially troubling” levels of methane and CO2 from the rapidly warming Arctic. Given the staggering amount of carbon trapped in the permafrost — and the fact that methane is a very potent heat-trapping gas — the space agency is now asking: “Is a Sleeping Climate Giant Stirring in the Arctic?”

“Permafrost zones occupy nearly a quarter of the exposed land area of the Northern Hemisphere. NASA’s Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) is probing deep into the frozen lands above the Arctic Circle in Alaska to measure emissions of the greenhouse gases carbon dioxide and methane from thawing permafrost — signals that may hold a key to Earth’s climate future.” Credit: UNEP

We’ve known for a while that “permafrost” was a misnomer (see “Thawing permafrost feedback will turn Arctic from carbon sink to source in the 2020s“). The defrosting permamelt will likely add up to 1.5°F to total global warming by 2100.

Two studies from February provide more evidence the process may happen even faster than we thought:

• 500,000-Year History of Permafrost Reveals Further Warming of 1.5°C Would ‘Thaw Significant Regions’
• “Surface exposure to sunlight stimulates CO₂ release from permafrost soil carbon in the Arctic”

Now we are getting some of the first detailed observations of carbon emissions from the thawing permafrost thanks to the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), “a five-year NASA-led field campaign studying how climate change is affecting the Arctic’s carbon cycle.”

Flying in a specially instrumented C-23 Sherpa aircraft only 500 feet above the ground, CARVE scientists “measure interesting exchanges of carbon taking place between Earth’s surface and atmosphere,” something most other airborne permafrost measurement missions can’t do. The goal:

Ultimately, the scientists hope their observations will indicate whether an irreversible permafrost tipping point may be near at hand. While scientists don’t yet believe the Arctic has reached that tipping point, no one knows for sure.

NASA’s news release is one of the best I’ve ever seen from any source. I’ll quote it at length since its factoids and findings are so citable.

Let’s start with just how fast the permafrost has been heating up. CARVE principal investigator Charles Miller of NASA’s Jet Propulsion Laboratory explains:
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The East coast was drenched by record-smashing tropical storm Andrea this week.

Predicted rainfall for the 48-hour period from 8 am EDT Friday, June 7, to 8 am EDT Sunday, June 8, 2013. Image credit: NOAA.

The L.A. Times reported a few of the records demolished by this early-season tropical storm:

In some places, rainfall measurements smashed century-old totals as flash flooding occurred. Central Park saw 4.16 inches of rain, more than double the record set in 1918. No major damage was reported.

Philadelphia International Airport measured 3.5 inches of rain, compared to the 1.79-inch mark set in 1904. In Newark, N.J., 3.71 inches of rain broke a 1931 measurement of 1.11 inches.

Meteorologist and former hurricane Hunter Dr. Jeff Masters discusses the long-term trend:

Andrea’s formation in June continues a pattern of an unusually large number of early-season Atlantic named storms we’ve seen in recent years. Climatologically, June is the second quietest month of the Atlantic hurricane season, behind November. During the period 1870 – 2012, we averaged one named storm every two years in June, and 0.7 named storms per year during May and June. In the nineteen years since the current active hurricane period began in 1995, there have been fifteen June named storms (if we include 2013′s Tropical Storm Andrea.) June activity has nearly doubled since 1995, and May activity has more than doubled (there were seventeen May storms in the 75-year period 1870 – 1994, compared to 6 in the 19-year period 1995 – 2013.) Some of this difference can be attributed to observation gaps, due to the lack of satellite data before 1966.

However, even during the satellite era, we have seen an increase in both early season (May – June) and late season (November – December) Atlantic tropical storms. Dr. Jim Kossin of the University of Wisconsin looked at the reasons for this in a 2008 paper titled, “Is the North Atlantic hurricane season getting longer?” He concluded that there is a “apparent tendency toward more common early- and late-season storms that correlates with warming Sea Surface Temperature but the uncertainty in these relationships is high.” He found that hurricane season for both the period 1950-2007 and 1980-2007 got longer by 5 to 10 days per decade (see my blog post on the paper.)

This post has been updated.

Related Post:

• New Research Finds Humans Causing More Strong Hurricanes

Internationally, the big hurdle to fighting climate change and global warming is figuring out a fair way to divvy up responsibility. Serious efforts to curb carbon emissions will require considerable upfront investment, so who should make those investments and how much? That impasse then influences domestic political reluctance in the United States. If the rest of the world isn’t moving, why should we?

Earlier this week, Bloomberg flagged work by the Stockholm Environment Institute and others to nail down answers to those questions with hard numbers. Their conclusion?

As of now, the United States bears fully one third of the burden to reduce global carbon emissions, with much of Europe shouldering nearly another third. It’s a bracing conclusion. The latest analysis suggests the per-unit social and economic damage from carbon emissions due to global warming is as much as twice what we thought. Several countries with much more modest obligations than America’s have already moved to price carbon, leaving the U.S. sticking out like a sore thumb. Even China is tip-toeing up to it.

Much of the researchers’ work comes from the Greenhouse Development Rights Framework. First, they set a global threshold for living standards, below which people are considered free from the responsibility to sacrifice in the fight against climate change. They came up with $7,500 a year in dollars (adjusted for purchasing power parity) — it’s the living standard at which malnutrition, infant mortality, low education, and other problems of poverty begin to fade, plus a bit of breathing room. Even then, about 70 percent of the globe lives at or below this level, and taken all together is responsible for only 15 percent of the cumulative global emissions.

Capacity to invest in climate mitigation and adaptation was then defined as all income per person falling above that threshold. As you can see below, the United States’ capacity swamps that of both India and China, despite the much larger populations of the latter two countries:

The researchers then tried to quantify responsibility for climate change by accounting for cumulative emissions since 1990, and all projected emissions going forward, while excluding all emissions associated with income below the threshold. Putting it all together, they calculated the “responsibility and capacity indicator” (RCI) for each country. In other words: everyone’s fair share of the responsibility to reduce carbon emissions enough to keep the planet’s climate under two degrees Celsius of warming.

The result? The United States has 33.1 percent of the global RCI in 2010, dropping to 25.5 percent in 2030. The European Union has 25.7 percent in 2010 and 19.6 percent in 2030. Thanks to its economic growth, China does jump from 5.5 percent in 2010 to 15.2 percent in 2030. But no other country even cracks 8 percent, or changes much over that period.

This shouldn’t be surprising. Other data suggests the U.S. can claim a third of the world’s carbon dioxide emissions since the mid-1800s, and our per capita emissions top nearly every other nation. We’re also the most economically developed nation without a price on carbon, meaning we implicitly subsidize fossil fuel use far more than anyone else.

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Sea level rise last century versus the last two decades via Jet Propulsion Lab.

Is it big news that “Rising Sea Level Tied to Faster Melt,” as the Wall Street Journal reported today?

Back in 2011, JPL researchers concluded that polar ice sheet mass loss is speeding up, threatening a 1 foot sea level rise by 2050. Last year, the most comprehensive analysis of all observational data found that Greenland ice sheet melt is up nearly five-fold since mid-1990s.

Changes in global sea level due to ice sheet melting since 1992. Credit: NASA via NBC.

But I think it qualifies as news when the Wall Street Journal actually does an original piece on one of the more worrisome threats from global warming — and gets it right.

Indeed the Wall Street Journal reporters and editorial page editors are kind of like Edward Norton and Brad Pitt (respectively) in Fight Club (spoiler alert) raging a schizophrenic war with one another (literally). The WSJ editors set the first rule of global warming fight club — don’t talk about the threat of manmade global warming (see Not The Onion: Wall Street Journal Hits ‘Rock Bottom’ With Inane Op-Ed Urging ‘More Atmospheric Carbon Dioxide’)

The more sane half of the WSJ reported on a new study in Nature Geoscience, whose abstract explains:

… we conclude that most of the change in ocean mass is caused by the melting of polar ice sheets and mountain glaciers. This contribution of ice melt is larger than previous estimates, but agrees with reports of accelerated ice melt in recent years.

Here is how a rogue reporter at the WSJ covered it:
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A (new) paper by Qing-Bin Lu in the International Journal of Modern Physics B is gaining attention for asserting that chlorofluorocarbons (CFCs), not CO₂, is causing global warming. This sensationalist headline is typically repeated with little mention that Lu’s claims are not new, and they have not held up to scientific scrutiny in the past.

The following is a guest post by Climate Nexus. Text in PDF format here.

A new paper by Qing-Bin Lu in the International Journal of Modern Physics B is gaining coverage for its claim that chlorofluorocarbons (CFCs), not CO₂, is causing global warming. This sensationalist headline is often repeated with little mention that Lu’s claims are not new, and have not held up to scientific scrutiny in the past. In fact, Lu has been promoting his theories about CFCs for years, and mainstream scientists have found no merit in them. Critics have said Lu makes a fundamental scientific error by confusing correlation with causation, and does not effectively challenge the physical evidence of the warming effects of CO₂, a body of knowledge built up over 150 years.

The claim:

Lu argues that CFCs are responsible for causing global warming. He uses a complicated chain of logic starting with the premise that it is cosmic rays, not UV rays as most scientists think, that break down CFCs, and ending with the finding that after his calculations, the estimated warming impact of CFCs matches up closely with actual measured surface temperatures. He concludes that it must be CFCs, not CO₂, that are causing surface temperatures to rise.

The facts:

- This theory has been considered and dismissed before. A 2010 report by the National Academies of Science was commissioned by Congress to examine all the evidence surrounding global warming including the theory that cosmic rays might influence Earth’s climate. It concluded that “a plausible physical mechanism… has not been demonstrated” and “cosmic rays are not regarded as an important climate forcing.”

- In 2011, a peer-reviewed paper found that Lu’s conclusions “are based solely on correlation… do not have a physical basis… and the findings of the IPCC… remain unchallenged.”

- In response to Lu’s most recent publication, several different scientists interviewed by the Vancouver Sun each said that Lu’s conclusions “[go] against 150 years of very fundamental physics.”

- Critics point out that Lu’s paper fails to make the leap from correlation to causation, one of the most basic and most common scientific failings. This error is simply illustrated in the classic fable of the rooster who believes the sun rises because he crows. Two things may happen at the same time, but this does not mean one causes the other. A “physical mechanism” by which the two events are connected must be known, in order to fully understand causation.

- In contrast, there is strong experimental evidence of the physical mechanism by which CO₂ warms the planet, evidence that (as scientists have mentioned already in response to Lu) dates back 150 years.

Via Climate Science Watch. Top Chart via UK Telegraph.

While the overall warming is about 0.16°C per decade, there are three ten-year periods where there was a hiatus in warming, as the graph above shows, from 1977 to 1986, from 1987 to 1996, and from 2001 to 2012. But at each end of these periods there were big jumps. We find exactly the same sort of flat periods in climate model projections, lasting easily up to 15 years in length.

by Kevin Trenberth via The Conversation

Has global warming stalled? This question is increasingly being asked because the local weather seems cool and wet, or because the global mean temperature is not increasing at its earlier rate or the long-term rate expected from climate model projections.

The answer depends a lot on what one means by “global warming.” For some it is equated to the “global mean temperature.” That keeps going up but also has ups and downs from year to year. More on that shortly.

Why should it go up? Well, because the planet is warming as a result of human activities. With increasing carbon dioxide and other heat-trapping greenhouse gases in the atmosphere, there is an imbalance in energy flows in and out of the top of the atmosphere: the greenhouse gases increasingly trap more radiation and hence create warming. “Warming” really means heating, and this can exhibit itself in many ways.

Rising surface temperatures are just one manifestation. Melting Arctic sea ice is another. So is melting of glaciers and other land ice that contribute to rising sea levels. Increasing the water cycle and invigorating storms is yet another. But most (more than 90%) of the energy imbalance goes into the ocean, and several analyses have now shown this. But even there, how much warms the upper layers of the ocean, as opposed to how much penetrates deeper into the ocean where it may not have much immediate influence, is a key issue.

The ups and downs of global temperature

My colleagues and I have just published a new analysis showing that in the past decade about 30% of the heat has been dumped at levels below 700m, where most previous analyses stop.

The first point is that this is fairly new; it is not there throughout the record. The cause of the shift is a particular change in winds, especially in the Pacific Ocean where the subtropical trade winds have become noticeably stronger, changing ocean currents and providing a mechanism for heat to be carried down into the ocean. This is associated with weather patterns in the Pacific, which are in turn related to the La Niña phase of the El Niño phenomenon.

The second point is that we have found distinctive variations in global warming with El Niño. A mini global warming, in the sense of a global temperature increase, occurs in the latter stages of an El Niño event, as heat comes out of the ocean and warms the atmosphere. The ocean’s temperature is also affected by volcanic eruptions, which also affect the perceptions of global warming.

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At a May 16 televised forum on the recovery from Superstorm Sandy, a former top military infrastructure official called on Americans to “stop ignoring” climate change and “realize it’s the new reality.”

At the Sandy town hall organized by public television stations NJTV and WNET, John Boulé, the former commander of the New York District, Army Corps of Engineers, warned New Yorkers to stop ignoring climate change and start preparing for higher sea level rise and more frequent and more powerful storms:

First of all, we’ve got to realize it’s the new reality. Climate change is real. It’s more than sea level rise that’s going to happen over the course of the next 100 years. It’s greater storm intensities, it’s greater storm frequencies. We’ve got to stop ignoring it and start planning and building to reduce the risk to the public. That’s where we are.

Watch it:

Like Boulé, other panelists, including PSE&G president Ralph LaRossa, recognized the “new reality” of rising seas and extreme weather. Although these words are welcome, the most important element of facing the reality of climate change is understanding that it’s caused by human activities — something no-one at the forum did. In fact, Richard Ravitch, the real-estate scion and former Democratic lieutenant governor of New York, blamed “forces of nature” on sea level rise.

At no point during the two-hour forum did any panelist or reporter discuss the manmade causes of climate change or recommend opposing the threat to civilization posed by the fossil-fuel industry. The words “fossil fuels,” “carbon”, “greenhouse,” “pollution,” and “oil” were never mentioned. Also not mentioned was David Koch, the carbon pollution billionaire and richest man in New York, who was on the board of WNET from 2006 until the day of the forum. At the WNET board meeting on the morning of May 16, Koch’s resignation was accepted.

By Michael D. Lemonick via Climate Central

When 97 percent of Greenland’s ice experienced at least some melting in July 2012, scientists wondered if it was a one-time phenomenon. Now a new study in Geophysical Research Letters indicates it is a sign of things to come and by 2025, there is a 50-50 chance of it happening annually.

Extent of surface melt over Greenland’s ice sheet on July 8, 2012 (left) and July 12, 2012. In just a few days, the melting had dramatically accelerated and an estimated 97 percent of the ice sheet surface had thawed. Credit: NASA.

It’s not clear what the effects of such melting will be: the majority of Greenland’s ice loss, which has accelerated significantly over the past decade, comes from glaciers shedding more ice into the sea, and moving faster toward the sea, not from melting snow and ice at higher elevations of the ice sheet.

Nevertheless, such widespread melting indicates an overall warming in the region that could threaten the ice more generally, adding significantly to the threat of sea level rise.

The 2025 projection is based on two factors, according to lead author Dan McGrath, a glaciologist at the University of Colorado, Boulder. The first is a series of temperature measurements going back to 1950 at the Summit research station, at the highest — and on average, the coldest — point on the Greenland ice sheet. The mercury has been rising more or less steadily there for that entire time, with the fastest increase, of about .22° F per year, coming since 1992. “That’s six times faster than the global average,” McGrath said in an interview.

The highest parts of the ice sheet still remain below the freezing mark virtually all the time, but when unusual weather conditions set in — an especially warm air mass, or as in the case of the 2012 melting, an influx of clouds just thin enough to let sunlight through but thick enough to block heat from escaping — the thermometer can sneak above 32°F. “Only an hour above freezing is enough to start the surface melting,” McGrath said.

Another factor that went into the analysis involved what’s known as the equilibrium line — the altitude where the snow is neither piling up year to year nor shrinking. Over the past 20 years or so, that transition zone has been gradually moving up the ice sheet by about 115 feet every year, on average— another indication that temperatures on the frozen island are warming.

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Sarah Palin took to Facebook again this weekend, posting about her youngest daughter’s graduation in the Alaskan snow:

One last blast of Alaska winter today, hopefully? This is what “Grad Blast” means in Alaska! We’ll move our graduation b-b-q indoors and watch the mini-blizzard from ’round the fireplace. (Global warming my gluteus maximus.)

When Palin was running for national office, she advocated capping carbon emissions and said man’s activities contribute to global warming. Over the last half decade, she has swung back to rejecting climate science and embracing carbon emissions:

Aug. 2008: Asked about global warming, said “I’m not one though who would attribute it to being man-made.”

Sep. 2008: Told Charlie Gibson: “I believe that man’s activities can certainly be contributing to the issue of global warming, climate change.”

Oct. 2008: Said during the vice presidential debate that she supported capping carbon emissions.

May 2009: Forced to cancel an appearance at White House Correspondents’ dinner because of a flooding disaster caused by an “unusually warm spring thaw in Alaska.”

Nov. 2009: Asked Rush Limbaugh, “Are we warming or are we cooling?”

Dec. 2009: Attacked climate scientists in a Washington Post op-ed, then said she would not debate Al Gore on climate change because “they don’t want to listen to the facts. They don’t want to listen to some reasonable voices in this.”

Feb. 2010: Asserted that climate science is “snake oil” and said “man-made global warming hysteria isn’t based on sound science.”

Apr. 2010: Dismissed “this snake oil science stuff that is based on this global warming, Gore-gate stuff

Jun. 2010: In the wake of the Deepwater Horizon spill, said “I chant, ‘drill, baby, drill,’ because it will help make the country energy independent.”

May 2011: At a motorcycle rally, exclaimed: “I love that smell of the emissions!”

Jan. 2012: In the middle of last winter, took to Facebook to ask, “What global warming?”.

Apr. 2012: Celebrated Earth Day by calling, yet again, to “drill, baby, drill.”

Palin is an entertainer now rather than a public servant and so her opinions alone do not merit much consideration. Yet her joking asides that cold weather means that climate change is not happening are representative of a larger skepticism and confusion about the link between climate and weather.

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