National Assessment Finds Climate Change “Has Moved Firmly into the Present”
The effects of human-induced climate change are being felt in every corner of the United States. . . . If greenhouse gases like carbon dioxide and methane continue to escalate at a rapid pace, [scientists] said, the warming could conceivably exceed 10 degrees by the end of this century.
—“U.S. Climate Has Already Changed, Study Finds, Citing Heat and Floods,” New York Times  (5/7/14)
Melting of West Antarctic Ice Sheet “Has Passed Point of No Return”
Scientists say that the melting will continue as long as the heat-trapping carbon dioxide in the atmosphere increases. Even if carbon dioxide and temperatures stabilize, the melting and shifting of glaciers will continue for decades or centuries as they adjust to the new equilibrium.
—“The Big Melt Accelerates,” New York Times  (5/20/14)
Two major reports released in recent weeks state emphatically that dramatic changes in climate are under way in the United States and globally, with a 10-degree average temperature rise in the U.S. possible by 2100, and world sea levels likely to rise by 4 to 12 feet or more by the end of the century. Perhaps most ominous of all, according to papers published last week in Science  and Geophysical Research Letters , the melting of the West Antarctic Ice Sheet has already “passed a point of no return,” which will lead to alarming sea level rises that will imperil—or render uninhabitable—coastal and low-lying cities  around the planet: New Orleans, New York, Miami, Boston, Venice, Shanghai, Mumbai . . .
A good summary by NASA of the Science and Geophysical Research Letters papers’ findings, along with an explanatory video, can be found here .
More Intense, Frequent Extreme Weather Projected for U.S.
The National Climate Assessment , released by the White House on May 6, was conducted by a team of more than 300 experts guided by a 60-member Federal Advisory Committee and reviewed by the National Academy of Sciences. Among the Assessment’s many noteworthy findings: “The intensity, frequency, and duration of North Atlantic hurricanes , as well as the frequency of the strongest hurricanes, have all increased since the early 1980s. Hurricane intensity and rainfall are projected to increase as the climate continues to warm.”
The Assessment also projects increases in extreme weather  generally, both in intensity and frequency: heat waves, droughts, wildfires, along with (in other places) excessive rainfall, flooding, tornadoes “and other severe thunderstorm phenomena,” etc.:
The number of extremely hot days is projected to continue to increase over much of the United States, especially by late century. Summer temperatures are projected to continue rising, and a reduction of soil moisture, which exacerbates heat waves, is projected for much of the western and central U.S. in summer.
In a good summary  of 12 points the Obama administration wants the American public to understand from the Climate Assessment, Grist.org includes one point (among others) that this blog takes very seriously: “Infrastructure is being damaged by sea level rise, heavy downpours, and extreme heat; damages are projected to increase with continued climate change.” (See Further Reading below.)
The Climate Assessment’s findings on sea level rise  make for chilling reading:
The oceans are absorbing over 90% of the increased atmospheric heat associated with emissions from human activity. Like mercury in a thermometer, water expands as it warms up (this is referred to as “thermal expansion”) causing sea levels to rise. Melting of glaciers and ice sheets is also contributing to sea level rise at increasing rates.
Recent projections show that for even the lowest emissions scenarios, thermal expansion of ocean waters and the melting of small mountain glaciers will result in 11 inches of sea level rise by 2100, even without any contribution from the ice sheets in Greenland and Antarctica. This suggests that about 1 foot of global sea level rise by 2100 is probably a realistic low end. On the high end, recent work suggests that 4 feet is plausible. . . . some decision makers may wish to use a wider range of scenarios, from 8 inches to 6.6 feet by 2100.
West Antarctic Melting “Appears Unstoppable”
A study led by NASA finds that major glaciers in the West Antarctic Ice Sheet (shown in orange-red above)—which alone contain the equivalent of 4 feet of sea level rise—appear to have become destabilized beyond repair; their collapse “appears unstoppable.” Researchers find “continuous and rapid retreat”—two glaciers there have receded some 22 miles since 1992—and authors of the study see “no [major] obstacle that would prevent the glaciers from further retreat.” (Antarctica holds 90 percent of the world’s ice; a complete meltdown—not inconceivable—would raise global sea level by some 215 feet.)
The NASA press release says the West Antarctic glaciers “have passed the point of no return.” The video  above illustrates the big melt. The process may take several hundred years, or a millennium, but there is no comfort in the potential slow motion: Recent studies have found scientists’ earlier predictions have often proved too cautious (they try not to be alarmist; see below), and many climatic changes have been accelerating faster than originally feared.
Scientists said the ice sheet was not melting because of warmer air temperatures, but rather because relatively warm water that occurs naturally in the depths of the ocean was being pulled to the surface by an intensification, over the past several decades, of the powerful winds that encircle Antarctica. (NYT  5/12/14)
(It is warmer water, by the way, that intensifies the power of hurricanes; such was the case with Hurricane Katrina. Climate change does not necessarily cause hurricanes, per se, but when tropical storms do arise the warmer sea water turbocharges them.)
The National Academy of Sciences says  that the earth’s major ice sheets—the poles and Greenland—hold enough frozen water to raise sea levels by some 200 feet. The ice melt from Greenland alone has raised global sea levels by more than a quarter-inch since the early 1990s. In previous years only limited parts of Greenland melted in summer; now there is no part of Greenland that does not melt to some extent. Greenland holds 10 percent of the world’s ice, enough to raise the sea level some 23 feet. An additional worrying factor is that the many wildfires made more common by climate change release soot into the atmosphere, which settle on the ice and darken it, reducing the ice’s reflectivity and, in effect, causing the ice to absorb more sunlight thus melt faster.
This Is Not an “Alarmist” Exaggeration
Some science writers note that, far from being “alarmist,” scientists tend to understate the severity of the earth’s environmental predicament. As The New Yorker’s Elizabeth Kolbert observes,
“The unfortunate fact about uncertainty is that the error bars always go in both directions. While it is possible that the problem could turn out to be less serious than the consensus forecast, it is equally likely to turn out to be more serious. In fact, it increasingly appears that, if there is any systemic bias in the climate models, it’s that they understate the gravity of the situation.” —Elizabeth Kolbert, “The West Antarctic Ice Sheet Melt : Defending the Drama” in The New Yorker (5/13/14)
Fear Not—Organize (or, Despair Is Not the Right Response)
The scientists’ projections are serious, dire, and depressing—no question about it. But the right response—the honorable and moral response—is not to give up hope and succumb to defeat, but rather to summon courage and try to resist and press local, state, and national officials and businesses to mend their ways as rapidly and thoroughly as possible. We can limit the damage. All is not lost. For example, The New York Times reports (5/22/14) that billionaire environmental activist Tom Steyer  of California is promising to spend $50 million of his own fortune and his super-PAC NextGen Climate  in the 2014 congressional elections to make sure climate change is a prominent issue, and to assist the campaigns of environmentally serious candidates.
Most Republicans are ideologically unwilling or unable to face reality, but one, Jon M. Huntsman Jr. of Utah, a former ambassador to China and the GOP’s most admirable candidate in the 2012 primaries, recently wrote an Op-Ed  for The New York Times arguing that Republicans must no longer ignore climate change as a scientific fact: “Our approach as a party should be one of neither denial nor extremism. Science must guide sensible policy discussions that will lead to well-informed choices, which may mean considering unexpected alternatives.” Huntsman then quotes the great Republican conservationist of a century ago, Theodore Roosevelt:
“To waste, to destroy our natural resources, to skin and exhaust the land instead of using it so as to increase its usefulness, will result in undermining in the days of our children the very prosperity which we ought by right to hand down to them amplified and developed.”
We could not agree more, and we feel very strongly that how the American public responds to this challenge—or not—and how the humans of Planet Earth organize and force governments and businesses and all the powers that be to mend our ways will be our legacy to coming generations of humanity, and other living things. The Industrial Revolution began about 250 to 300 years ago, and it has not taken humankind—or at least its industrial, carbon-producing elements—long to bring the planet to the brink of ecological destruction and mayhem.
We asked Mark S. Davis , former director of the Coalition to Restore Coastal Louisiana and now Senior Research Fellow and Director of the Institute on Water Resources Law and Policy at Tulane University, for his thoughts on what the reports mean for New Orleans, Louisiana, and the Gulf Coast and the U.S. generally (admittedly a tall order). He replied:
We [in Louisiana] have some land-building and sustaining capacity but we also need to start managing to reduce subsidence (we are not alone in that), and factoring in potential sea level rise scenarios. We do that some, but not enough; the predictions keep getting worse . . . Since most public and private risk management decisions are made with a pretty short horizon in mind, I don’t expect a really glum forecast for 100 years out to change much behavior today—however much I might advise otherwise. Most people, firms, and governments have real trouble planning for things more than five years in the future. Thirty years—the length of a mortgage—is almost an eternity, which explains a lot when you think about it.
Unfortunately, at the moment we are acting out our hopes more than we are acting on what the facts are telling us. Ignoring this information and what it portends may well be our defining act of ignorance and arrogance.
Grist reports  that environmental activist and author Bill McKibben , author of The End of Nature, is organizing “A Call to Arms : An Invitation to Demand Action on Climate Change” for September 20–21 in New York City when the delegates to the United Nations assemble for the UN’s annual proceedings. McKibben writes  in Rolling Stone:
My guess is people will come by the tens of thousands, and it will be the largest demonstration yet of human resolve in the face of climate change. Sure, some of it will be exciting—who doesn’t like the chance to march and sing and carry a clever sign through the canyons of Manhattan? But this is dead-serious business, a signal moment in the gathering fight of human beings to do something about global warming before it’s too late to do anything but watch. You’ll tell your grandchildren, assuming we win. So circle September 20th and 21st on your calendar . . .
Here’s a banner I know you’ll see in the streets of New York: CLIMATE/JOBS. TWO CRISES, ONE SOLUTION.
National Climate Assessment Report 2014  (“A team of more than 300 experts guided by a 60-member Federal Advisory Committee produced the report, which was extensively reviewed by the public and experts, including federal agencies and a panel of the National Academy of Sciences.”)
U.S. Climate Has Already Changed, Study Finds, Citing Heat and Floods  (NYT 5/6/14)
Scientists Warn of Rising Oceans from Polar Melt  (NYT 5/12/14)
This Is What a Holy Shit Moment for Global Warming Looks Like  (Mother Jones, 5/12/14)
Humans Have Already Set in Motion 69 Feet of Sea Level Rise  (Mother Jones, 1/31/13)
The Arctic Ice Crisis : Greenland’s glaciers are melting far faster than scientists expected (Bill McKibben in Rolling Stone, 8/16/12)
12 things the Obama administration wants you to know about climate change  (Grist.org on the National Climate Assessment)
Just 90 Companies Caused Two-Thirds of Man-Made Global Warming Emissions  (Mother Jones, 11/20/13)
What Climate Change Will Do to Your City : By 2300, these iconic cities [New Orleans omitted] could be underwater
150 Years in 30 Seconds: Sea Level Debt Sinking U.S. Cities  (ClimateCentral)
NextGen Climate.org 
Muir Glacier at Glacier Bay National Park and Preserve in Alaska is among the many worldwide that are disappearing. Muir, left, as seen in August 1941, and photographed in August 2004. Credit W. Field; B. Molnia/U.S.G.S., via Glacier Photograph Collection
Solar flare + hurricane image courtesy of Salon.com.