South Okiehomeland needs rain
How Bad is the Texas Drought? “In Austin, They are Praying for a Hurricane”
By Joe Romm on Jun 29, 2011 at 5:25 pm
This is “the worst Texas drought since record-keeping began 116 years ago.” Drought and wildfires have led the US Department of Agriculture “to declare the entire state of Texas a natural disaster.” Over 70% of the state was in “exceptional” drought last week, with another 20% in “extreme” drought, and “213 counties in Texas have lost at least 30 percent of their crops or pasture.”
You know a drought is devastating when people are so desperate for relief they start rooting for a catastrophic deluge. But that’s what NPR reported today:
The word drought doesn’t really capture what’s happening in Texas. The last nine months have been the driest in state history. Instead of rain, spring brought nearly half a million acres of wildfires. And in central Texas, around Austin one of the area’s largest lakes is drying up.
That’s why I prefer Dust-Bowlification. And if drought doesn’t capture what’s happening now, it certainly won’t capture what we face if we don’t reduce greenhouse gas emissions sharply (see U.S. southwest could see a 60-year drought this century). Back to NPR:
Haskell Simon has been farming rice in Matagorda county near the Gulf of Mexico since the 1940s. He says that over the last 15 years the rice planting season has been getting earlier and earlier, because the South Texas climate is getting hotter and hotter….
In Austin, they’re praying for a hurricane, a nice slow moving category one or two, or a tropical storm, that makes its way up to Austin and then stalls out over the Texas hill country.
And the Southwest isn’t the only part of the country that is facing the alternating twin threats of Dust Bowl and deluge, Hell and High Water. (see “Study: Global warming is driving increased frequency of extreme wet or dry summer weather in southeast, so droughts and deluges are likely to get worse“)
NPR quotes farmer Simon about the change, “Typically LCRA [Lower Colorado River Authority] would turn on the irrigation water pumps by April 15th. And now the pumps can be started as early as March the 1st. So something is happening, obviously, there.”
Something is happening. Obviously. Too bad NPR — the supposedly liberal (aka science-based) media — can’t be bothered to stick in even one sentence explaining exactly why the South Texas climate is getting hotter and hotter. Or how we can be quite certain it’s going to get much, much worse.
What’s surprising about that crucial omission is NOAA’s National Climatic Data Center just released its final State of the Climate in 2010 report, and their climate experts were pretty blunt. As AFP in its piece, “Experts warn epic weather ravaging US could worsen“:
Epic floods, massive wildfires, drought and the deadliest tornado season in 60 years are ravaging the United States, with scientists warning that climate change will bring even more extreme weather.The human and economic toll over just the past few months has been staggering: hundreds of people have died, and thousands of homes and millions of acres have been lost at a cost estimated at more than $20 billion.
The piece quoted, Deke Arndt, NOAA’s chief of climate monitoring:
Arndt said this spring’s extreme weather is in line with what is forecast for the future.”In general, but not everywhere, it is expected that the wetter places will get wetter and the drier places will tend to see more prolonged dry periods,” he told AFP.
“We are seeing an increase in the amount (of rain and snow) that comes at once, and the ramifications are that it’s a lot more water to deal with at a time, so you see things like flooding.”
More than 6.8 million acres in the central United States have been swamped after record spring rainfall overwhelmed rivers already swollen from the melting of a heavy winter snow pack….
Meanwhile, the southern United States is dealing with one of the most extreme droughts since the dust bowl of the 1930s, and the dry conditions have led to massive and uncontrollable wildfires.
More than 4.7 million acres have been burned in some 32,000 separate fires so far this year, which is more than twice the annual average over the past decade, according to the National Interagency Fire Center.
Other climate experts have been equally blunt about what is to come:
… the intensity of future droughts, heat waves, storms and floods is expected to rise drastically if greenhouse gas emissions don’t stabilize soon, said Michael Mann, a scientist at Penn State University.
Note: AFP means “if greenhouse gas concentrations don’t stabilize soon.” Stabilizing emissions wouldn’t stop weather from getting more and more extreme throughout the century:
“Even a couple degree warming can make a 100-year event a three-year event,” Mann, the head of the university’s earth systems science center, told AFP.
“It has to do with the tail of the bell curve. When you move the bell curve, that area changes dramatically.”
For more on that, see “NOAA: Monster crop-destroying Russian heat wave to be once-in-a-decade event by 2060s (or sooner).”
Scientific American has a three part series on this subject which is worth reading. From Part 1, “Storm Warnings: Extreme Weather Is a Product of Climate Change“:
“Our figures indicate a trend towards an increase in extreme weather events that can only be fully explained by climate change,” says Peter Höppe, head of Munich Re’s Geo Risks Research/Corporate Climate Center: “It’s as if the weather machine had changed up a gear.”
The second line of evidence comes from a nascent branch of science called climate attribution. The idea is to examine individual events like a detective investigating a crime, searching for telltale fingerprints of climate change. Those fingerprints are showing up—in the autumn floods of 2000 in England and Wales that were the worst on record, in the 2003 European heat wave that caused 14,000 deaths in France, in Hurricane Katrina—and, yes, probably even in Nashville. This doesn’t mean that the storms or hot spells wouldn’t have happened at all without climate change, but as scientists like Trenberth say, they wouldn’t have been as severe if humankind hadn’t already altered the planet’s climate.
From Part 2, “Global Warming and the Science of Extreme Weather: How rising temperatures change weather and produce fiercer, more frequent storms”:
Until recently scientists had only been able to say that more extreme weather is “consistent” with climate change caused by greenhouse gases that humans are emitting into the atmosphere. Now, however, they can begin to say that the odds of having extreme weather have increased because of human-caused atmospheric changes—and that many individual events would not have happened in the same way without global warming. The reason: The signal of climate change is finally emerging from the “noise”—the huge amount of natural variability in weather.
Scientists compare the normal variation in weather with rolls of the dice. Adding greenhouse gases to the atmosphere loads the dice, increasing odds of such extreme weather events. It’s not just that the weather dice are altered, however. As Steve Sherwood, co-director of the Climate Change Research Center at the University of New South Wales in Australia, puts it, “it is more like painting an extra spot on each face of one of the dice, so that it goes from 2 to 7 instead of 1 to 6. This increases the odds of rolling 11 or 12, but also makes it possible to roll 13.”
Why? Basic physics is at work: The planet has already warmed roughly 1 degree Celsius since preindustrial times, thanks to CO2and other greenhouse gases emitted into the atmosphere. And for every 1-degree C (1.8 degrees Fahrenheit) rise in temperature, the amount of moisture that the atmosphere can contain rises by 7 percent, explains Peter Stott, head of climate monitoring and attribution at the U.K. Met Office’s Hadley Center for Climate Change. “That’s quite dramatic,” he says. In some places, the increase has been much larger. Data gathered by Gene Takle, professor of meteorology at Iowa State University in Ames, show a 13 percent rise in summer moisture over the past 50 years in the state capital, Des Moines.
Droughts, too, will increase:
On a warmer planet, however, the dry air will travel farther north and south from the equator before it descends, climate models predict, making areas like the U.S. Southwest and the Mediterranean even drier. Such an expanded Hadley cell would also divert storms farther north. Are the models right? Richard Seager of Columbia University’s Lamont–Doherty Earth Observatory has been looking for a climate change–induced drying trend in the Southwest, “and there seems to be some tentative evidence that it is beginning to happen,” he says. “It gives us confidence in the models.” In fact, other studies show that the Hadley cells have not only expanded, they’ve expanded more than the models predicted.
Such a change in atmospheric circulation could explain both the current 11-year drought in the Southwest and Minnesota’s status as the number one U.S. state for tornadoes last year. On October 26, 2010, the Minneapolis area even experienced record low pressure in what Paul Douglas, founder and CEO of WeatherNation in Minnesota, dubbed a “landicane”—a hurricanelike storm that swept across the country. “I thought the windows of my home would blow in,” Douglas recalls. “I’ve chased tornados and flown into hurricanes but never experienced anything like this before.” Yet it makes sense in the context of climate change, he adds. “Every day, every week, another piece of the puzzle falls into place,” he says. “More extreme weather seems to have become the rule, not just in the U.S. but in Europe and Asia.”
thinkprogress.org |
