Monday, May 27, 2013

Global Warming

Global Warming Did It! Well, Maybe Not.
(By Joel Achenbach, Washington Post, August 2008)

We're heading into the heart of hurricane season, and any day now, a storm will barrel toward the United States, inspiring all the TV weather reporters to find a beach where they can lash themselves to a palm tree. We can be certain of two things: First, we'll be told that the wind is blowing very hard and the surf is up. Second, some expert will tell us that this storm might be a harbinger of global warming.

Somewhere along the line, global warming became the explanation for everything. Right-thinking people are not supposed to discuss any meteorological or geophysical event -- a hurricane, a wildfire, a heat wave, a drought, a flood, a blizzard, a tornado, a lightning strike, an unfamiliar breeze, a strange tingling on the neck -- without immediately invoking the climate crisis. It causes earthquakes, plagues and backyard gardening disappointments. Weird fungus on your tomato plants? Classic sign of global warming.  You are permitted to note, as a parenthetical, that no single weather calamity can be ascribed with absolute certainty (roll your eyes here to signal the exasperating fussiness of scientists) to what humans are doing to the atmosphere. But your tone will make it clear that this is just legalese, like the fine-print warnings on the flip side of a Lipitor ad.

Some people are impatient with even a token amount of equivocation. A science writer for Newsweek recently flat-out declared that this year's floods in the Midwest were the result of climate change, and in the process, she derided the wishy-washy climatologists who couldn't quite bring themselves to reach that conclusion (they "trip over themselves to absolve global warming").  Well, gosh, I dunno. Equivocation isn't a sign of cognitive weakness. Uncertainty is intrinsic to the scientific process, and sometimes you have to have the courage to stand up and say, "Maybe."  Seems to me that it's inherently impossible to prove a causal connection between climate and weather -- they're just two different things. Moreover, the evidence for man-made climate change is solid enough that it doesn't need to be bolstered by iffy claims. Rigorous science is the best weapon for persuading the public that this is a real problem that requires bold action. "Weather alarmism" gives ammunition to global-warming deniers. They're happy to fight on that turf, since they can say that a year with relatively few hurricanes (or a cold snap when you don't expect it) proves that global warming is a myth.  There's an ancillary issue here: Global warming threatens to suck all the oxygen out of any discussion of the environment. We wind up giving too little attention to habitat destruction, overfishing, invasive species tagging along with global trade and so on. You don't need a climate model to detect that big oil spill in the Mississippi. That "dead zone" in the Gulf of Mexico -- an oxygen-starved region the size of Massachusetts -- isn't caused by global warming, but by all that fertilizer spread on Midwest cornfields.

Some folks may actually get the notion that the planet will be safe if we all just start driving Priuses. But even if we cured ourselves of our addiction to fossil fuels and stabilized the planet's climate, we'd still have an environmental crisis on our hands. Our fundamental problem is that -- now it's my chance to sound hysterical -- humans are a species out of control. We've been hellbent on wrecking our environment pretty much since the day we figured out how to make fire.  This caused that: It would be nice if climate and weather were that simple.  But "one can only speak rationally about odds," Kerry Emanuel, a climatologist at the Massachusetts Institute of Technology who has studied hurricanes and climate change, told me last week. "Global warming increases the probabilities of floods and strong hurricanes, and that is all that you can say."  Emanuel's research shows that in the past 25 years, there's been an uptick in the number of strong storms, though not necessarily in the number of hurricanes overall. Climate models show that a 1-degree Celsius rise in sea-surface temperatures should intensify top winds by about 5 percent, which corresponds to a 15 percent increase in destructive power. The tropical Atlantic sea surface has warmed by 0.6 degrees Celsius in the past half-century.  At my request, Emanuel ran a computer program to see how much extra energy Hurricane Katrina had because of increases in sea-surface temperature. His conclusion: Katrina's winds were about 2 percent stronger in the Gulf, and not significantly stronger at landfall. Maybe climate change was a factor in generating such a storm, or in the amount of moisture it carried, but the catastrophe that Katrina caused in New Orleans can more plausibly be attributed to civil engineers who built inadequate levees, city planning that let neighborhoods materialize below sea level and Bush administration officials who didn't do such a heckuva job.

Let's go back to those Iowa floods. Humans surely contributed to the calamity: Farmland in the Midwest has been plumbed with drainage pipes; streams have been straightened; most of the state's wetlands have been engineered out of existence; land set aside for conservation is being put back into corn production to meet the demands of the ethanol boom. This is a landscape that's practically begging to have 500-year floods every decade.  Was climate change a factor in the floods? Maybe. A recent report from the National Oceanic and Atmospheric Administration said that heavier downpours are more likely in a warming world. Thomas Karl, a NOAA scientist, says that there has been a measurable increase in water vapor over parts of the United States and more precipitation in the Midwest.  But tree-ring data indicate that the state has gone through a cycle of increasing and decreasing rainfall for hundreds of years. The downpours this year weren't that unusual, according to Harry J. Hillaker Jr., the Iowa state meteorologist. "The intensity has not really been excessive on a short-term scale," he said. "We're not seeing three-inch-an-hour rainfall amounts."  This will be a wet year (as was last year), but Iowa may not set a rainfall record. The wettest year on record was 1993. The second wettest: 1881. The third wettest: 1902.

Iowa is an awkward place to talk about global warming, because the state has actually been a bit cooler in the summer than it was in the first half of the 20th century. Hillaker says the widespread shift to annual plants (corn and soybeans) and away from perennial grasses has altered the climate. The 10 hottest summers in Iowa have been, in order, 1936, 1934, 1901, 1988, 1983, 1931, 1921, 1955, 1933 and 1913. Talk about extreme weather: One day in 1936, Iowa set a state record with a high temperature of 117 degrees. And no one blamed it on global warming.  Rest assured, we may find ways to ruin the planet even before the worst effects of global warming kick in. The thing that gets you in the end is rarely the thing you're paying attention to.  The basic problem is that there are so many of us now. Four centuries ago, there were about 500 million people on Earth. Today there are that many, plus 6 billion. We're rapidly heading toward 9 billion. Conservatives say that we just need to focus on maintaining free markets and let everything sort itself out through the miracle of the invisible hand. But the political tide is turning against unfettered free markets and toward greater regulation. Climate-change policy is part of that: Somehow we've got to embed environmental effects into the cost of energy sources, consumer goods and so on. The market approach by itself has let us down.  Viewed broadly, it appears that humans are environment-destroying creatures by nature. The notion of the prelapsarian era in which we lived in perfect harmony with nature has been effectively shattered by such scientists as Jared Diamond, the author of "Collapse," and Tim Flannery, who wrote "The Future Eaters." If everything gets simplified and reduced to a global-warming narrative, we'll be unable to see the trees for the forest.   Last week, we saw reports of more wildfires in California. Sure as night follows day, people will lay some of the blame on climate change. But there's also the minor matter of people building homes in wildfire-susceptible forests, overgrown with vegetation due to decades of fire suppression. That's like pitching a tent on the railroad tracks.  The message that needs to be communicated to these people is: "Your problem is not global warming. Your problem is that you're nuts."  You should definitely worry about global warming. But you don't need to worry about global warming when your house is on fire.

Global Warming

(By Elizabeth Weise, USA TODAY)

 To the untrained eye, Bonanza Creek forest in Fairbanks, Alaska is breathtaking, a vibrant place alive with butterflies and birds, with evidence of moose and bear at every turn.  But look through forest ecologyist Glenn Juday's eyes, and you see a dying landscape.  Since the 1970s, climate change has doubled the growing season in some places and raised state temperatures 6 degrees in the winter and 3.5 on average annually since 1950, says Juday, a professor at the University of Alaska. Drought is killing spruce, aspen and birch trees.  Alaska has emerged as the poster state for global warming, the climate effect attributed to higher concentrations of "greenhouse" gases- mostly carbon dioxide created by burning fossil fuels- that capture the sun's heat in the atmosphere.  Global warming is a hot topic, especially now. Hurricane season begins soon, and climate researchers warn that rising ocean temperatures may bring more intense storms.  Ex- vice president Al Gore is back in the news with his acclaimed documentary on warming, An Inconvenient Truth.  President Bush, who has been criticized by environmental groups that say he has been slow to acknowledge the dangers posed by warming, said last week that "people in our country are rightly concerned about greenhouse gases and the environment."

     Alaska is important in measuring the effect of global warming on the USA because what happens here soon will be felt in the Lower 48 states, say experts such as Robert Corell, a senior fellow at the American Meteorological Society.  The spruce budworm, aspen leaf miner and the spruce bark beetle, pests once kept in check by winter cold, are flourishing here. Statewide, insect outbreaks have killed more than 4 million acres of forest in a decade and a half, says John Morton, a biologist at the Kenai National Wildlife Refuge in Soldotna.  Fires, long an integral part of the forest ecology here, are burning millions of acres as summers get longer and hotter, says Scott Rupp, a University of Alaska professor of forestry.  With each wave of fires, trees have a harder time coming back in the increasingly warm and dry landscape.  This great northern forest may end up a grassland. "Soon, people will be coming to the great plains of Alaska," Juday says.  Alaska is ahead of the climate-change curve because polar regions warm the fastest. They had long been kept frigid by vast regions of snow and ice that reflect 70% of the sun's energy back out to space.  But higher temperatures are shrinking that snow and ice cover. In the Arctic, summer sea ice has shrunk 15% to 20% in the past 30 years, according to 2005's Arctic Climate Impact Assessment report.

     As the snow and ice recede, the sun's rays are hitting more dark ground and water, which absorb most of the heat, reflecting just 20% of the energy away, says Matthew Sturm, a research scientist with the U.S. Army Corps of Engineers' Cold Regions Research Laboratory in Fairbanks.  Lakes and ponds are disappearing as the permafrost, permanently frozen ground that underlies much of Alaska north of Fairbanks, melts.  "It's like pulling the plug in a bathtub," says Peter Schweitzer, an anthropologist who works with the Arctic peoples in Alaska and Russia.  In some areas, as much as 40% of surface water has disappeared, taking with it vital habitat for ducks and other waterfowl, says Juday.  The permafrost that underlies much of the central and north of the state is a relic of the last Ice Age. Some of the frozen ground under Fairbanks is 100,000 years old, says Vladimir Romanovsky, a permafrost expert at Fairbanks. And it's now starting to get "slushy."  For Ruth Macchione, that meant a more expensive design to her new home after the cabin her husband built in the 1950s sank into the ground. The permafrost under the cabin thawed because the structure wasn't built to keep the ground cold- a key trick in building in cold regions.  Her new home incorporates piers to allow cold air to circulate underneath it.  "Local engineers are getting worried about higher ground temperatures, so they're specifying more pilings to combat that," says Billy Connor, director of the Alaska University Transportation Center. That will mean higher construction costs across the state, Sturm says.

     More heat means longer summers. The growing season in Fairbanks has gone from 80 to 120 days since records were first kept in the 1900s, says John Walsh, director of the Arctic System Research at the University of Alaska-Fairbanks.  But those summer days haven't come with any more rain, so plants and trees adapted to short, cool summers grow quickly but then dry out while it's still warm. That's one reason forest fires have become such a problem, he says.  In the Midwest and East, a few extra degrees can bring on higher milk prices. That's because cows don't like it hot. When the mercury gets over 80°F, milk production drops.  "Last year, we had herds that were down 5 to 15 pounds of milk per cow, and they'll usually be making 65 to 75 pounds" a day, says Larry Chase, a professor of animal science at Cornell.  In the Midwest, the corn belt is shrinking, says S. Elwynn Taylor, a professor of agricultural meteorology at Iowa State University in Ames. Especially at the western edges in Nebraska and the Dakotas, areas that were marginal for corn and soybeans are now unable to economically grow them.  David Lobell, an environmental scientist at Lawrence Livermore National Laboratory in Calif., says that for every 2°F increase in growing-season temperature, farmers can expect a 17% decline in yield for corn and soybeans.

     Taylor isn't convinced that the warming isn't simply part of a larger climate pattern that has been seen in the Midwest since about 1850. He is not alone. Other scientists see warming as part of a cyclical climate change, but they are outnumbered by colleagues who say the planet is warming steadily because human activity is adding to the greenhouse gases.  A landmark 2001 report by the United Nations' Intergovernmental Panel on Climate Change forecast that the average global surface temperature will increase 2.5 to 10°F above 1990 levels by 2100.  In White Mountain, a village of 200 on the western coast of Alaska near Nome, stocking up the larder is harder now for Rita Buck, a native Alaska Inupiaq.  Buck's year used to be a steady flow of work. First came salmon fishing, then harvesting berries. Salmonberries, a type of raspberry, would arrive first, then blueberries, blackberries and finally cranberries. Berries make up an important part of the subsistence diet.  But now, she says, the berries are blooming too early, when frost is still a danger. "It freezes all the berry blossoms and stops them growing," she says.  Cherry growers in Michigan, the nation's primary grower of tart cherries for pies, are having much the same problem. Spring now arrives seven to 10 days earlier there than in the 1970s, but cold snaps still come when they always have.  The commonly grown cherry variety isn't cold-hardy, so once it comes out of dormancy, it has no resistance to freezing, says Jeffrey Andresen, an agricultural meteorologist with Michigan State University.  "In 2002, early warming brought the tart cherry crop out of dormancy, and then a two-day freeze in April resulted in an almost complete loss for the year," he says.  Growers may have to plant new, more cold-hardy varieties, which won't be cheap, Andresen says. "You can't just pick up the trees and move them somewhere else."

     In Alaska, the sea ice that armors the coastline against winter storms is forming a week later than it used to, says David Atkinson, a Fairbanks professor of atmospheric science.  The state accounting office estimates that more than 100 coastal villages potentially face danger as winter storms erode their once-protected shorelines. The open water makes for stronger storms. Some areas have lost 30 feet of beach in a single storm, Atkinson says.  Warmer winters also are creating problems for California farmers of high-value crops such as peaches, plums, nectarines, almonds, pistachios and walnuts, which need a period of cold in the winter to bloom properly.  A series of warm winters has played havoc with fruit production, says Theodore DeJong, a professor of plant science. Farmers may have to switch out their current trees with low-chill varieties, expensive but at least a solution.  But for the trees that grow plums for prunes, that's simply not an option. It would take 10 to 20 years to develop low-chill varieties of these trees, DeJong says.  Packers already are moving some production to Chile. There could soon come a day when California, grower of 95% to 98% of all plums in the USA, is out of the business entirely.

     The huge fires that have hit Alaska in the past few summers filled the air with so much smoke and ash that people in Fairbanks at times wore dust masks and doctors told asthmatic patients to leave town until the fires were out.  U.S. asthma and allergy rates are increasing in part because more carbon dioxide in the atmosphere is supercharging the production of pollen that can trigger them. When carbon dioxide is doubled, ragweed stems grow 10% more but pollen increases by 60%.  "Pollen counts of 120 used to be cause for alert. We're seeing counts like 6,000 now," Epstein says.  Warmer winters also mean insects can survive and thrive in places where the cold used to keep them in check. Lyme disease is spreading beyond the former winter confines of the tick that carries it. And West Nile virus is spreading farther because spring drought amplifies the bird-biting mosquito cycle, Epstein says.  Ten years of change in the Arctic region is a preview of 25 years of change in the rest of the world, says Corell.  "This country is at its best when it has a grand challenge, whether it's World War II or going to the moon," says U. of New Hampshire professor Cameron Wake. "This is the next grand challenge."

Captivity Could Help Polar Bears Survive Global Warming Assault
(By Juliet Eilperin, Washington Post, March 25, 2012)

Polar bears are ideally suited to life in the Arctic: Their hair is without pigment, blending in with the snow; their heavy, strongly curved claws allow them to clamber over blocks of ice and snow and grip their prey securely; and their rough pads keep them from slipping.  The one thing they cannot survive is the disintegration of the ice. They range across the sea ice far from shore to hunt fatty seals, whose blubber sustains them.  Heat-trapping greenhouse gas emissions caused by burning fossil fuel are making the Arctic warm twice as fast as lower latitudes, and Arctic summer sea ice could disappear by 2030, according to climate models.  So a group of activists, zoo officials, lawmakers and scientists have a radical proposal: Increase the number of polar bears in U.S. zoos to help maintain the species’ genetic diversity if the wild population plummets.  In a worst-case scenario, a remnant group of bears would survive in captivity.













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