5 Signs Global Warming is Here
Sea squirts, poison ivy and other evidence that climate change is altering Connecticut's environment
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Tuesday, July 07, 2009
By Andy Bromage
Sea squirts are smothering Connecticut's shellfish industry.
Sea squirts are smothering Connecticut's shellfish industry.In the film The Day After Tomorrow, global warming looks like hell on Earth.
Polar ice caps melt, causing sea levels to rise and swallow Manhattan in a single tidal surge. Hail stones as big as footballs pummel Tokyo. Twisters rip through Los Angeles, destroying skyscrapers and shredding the Hollywood sign. Then comes a deep freeze, and the world is consumed in a second Ice Age.
In real life, global warming looks like a harmless yellow sea sponge. Non-native sea squirts, also known as Tunicate or sea pork, are proliferating in Long Island Sound and elsewhere as water temperatures rise. Marine scientists at the University of Connecticut found that warmer winters are causing the invasive invertebrates to explode in population. Sea squirts reproduce rapidly and compete with shellfish for food and space, threatening Connecticut's shellfish industry.
Like sea squirts, the early signs of global warming mostly fall into the non-life-threatening category: fast-spreading poison ivy and clinging kudzu vines. But that's just a preview of what's to come.
"What's happening today is a mild annoyance. This is nothing compared to what's around the corner," says Brenda Ekwurzel, a climate scientist with the Union of Concerned Scientists in Washington, D.C.
The U.S. House just passed, and the Senate will debate, the most sweeping climate change bill in a generation, one that would cap carbon emissions — a huge step toward curbing greenhouse gases.
Should smokestacks belch on unabated, Ekwurzel predicts, Connecticut's own day after tomorrow will feature fire ants, blood-sucking insects and suffocating summers as hot and humid as Georgia's.
Ekwurzel was a staff hydrologist at the Connecticut Department of Environmental Protection in the late 1980s (she lived in New Haven) and says signs of global warming are subtle, but there.
Conclusively linking these events to man-made climate change is tricky (see sidebar), but leading climatologists say they are consistent with what they'd expect a warming planet to do. Here are five clues that global warming has arrived in Connecticut. Senators, take note:
It's the Heat, Stupid
Temperatures in the northeast (Pennsylvania to Maine, including Connecticut) have risen sharply in the last 40 years, according to a 2007 study by the Union of Concerned Scientists.
Overall, the mercury's up 1.5 degrees on average since 1970, with the winter average being 4 degrees higher. The amount of ground covered by snow for longer than 30 days has decreased significantly, threatening cross-country skiing, snowball fights — and sugar maples. Warmer weather will push the trees north into Canada, scientists fear, decimating New England's maple sugar industry.
The Fish Switch
So long lobster, hello blue crab! The fish species inhabiting Long Island Sound are undergoing something of a sea change, says Peter Auster, a marine sciences professor at UConn.
Cold-water species like winter flounder, windowpane flounder and Atlantic herring are declining in number. Fish that like warmer climes, like weakfish, are on the rise, he says.
The die-offs that decimated Sound lobsters in 1999 and before can't be linked concretely to global warming, but it's hardly unthinkable, Auster says. In their place, blue crabs, which like warmer water, are reproducing like mad. "Between increased temperatures and stress on lobsters — warming certainly contributed to that."
One variable that complicates the theory: fishing. "The problem with working on fish is there's something called fishing going on," Auster says. "What's climate change and what's fishing is hard to say."
Attack of the Vines!
They call it "the vine that ate the south," but it must still be hungry. Once relegated to the south, kudzu vines have stretched into northern states too, including Connecticut. These invasives from Asia can grow up to a foot a day and strangle everything in their path.
Don't be fooled by the pretty flower they shoot up: kudzu kills other plants by smothering them and can get so heavy it uproots trees by the force of its weight. Kudzu now infects 2.5 million acres of farmland, fields and forests in the American south.
Scientists blame warmer, wetter weather for its arrival in the Nutmeg State. "It's a very voracious vine, so it can outcompete other vegetation," says Ekwurzel.
Ivy League
Poison ivy's going gangbusters as the globe heats up. Scientists at the Connecticut Agricultural Experiment Station in New Haven say poison ivy is spreading in the state, and some researchers think global warming is the culprit. A widely quoted 2006 study by Jacqueline E. Mohan of Duke University suggests that higher CO2 levels are causing poison ivy to spread and become more toxic. In her experiment, ivy exposed to higher CO2 levels averaged 149 percent faster growth than control plants.
See the Sea Squirts
In 2002, UConn scientists studied whether climate change was to blame for the growth of invasive sea squirts in Long Island Sound. The harmless-looking invertebrates outcompete economically vital shellfish like clams, mussels and oysters and smother other organisms. Left unchecked, they could have a devastating impact on shellfishing in the Sound.
And the warmer the water, the worse they get.
Scientists studied native species against invasive ones from 1991 to 2002 at Avery Point near Groton. They found that in the year after the warmest winter (1991), invasive growth was twice that of native squirts. By contrast, after the coldest winter (1994), the native ones outgrew the invasive sea squirts 5-to-1.¦
An Inconvenient Truthteller
Sandra Shumway believes in global warming. She also believes it's become a catchphrase scientists use for any number of unexplained biological and ecological phenomena. And something they throw around to attract research dollars.
"It makes it more relevant to granting agencies," says Shumway, a marine sciences professor at UConn.
Shumway, whose expertise is shellfish biology and the impacts of harmful algae on shellfish aquaculture, says linking ecological changes to climate change is a "leap of faith" some scientists make too easily.
"There are any number of factors that can alter environment and biological activities, temperature certainly being among them. It's not the only thing," she says. "That is not to say global warming isn't an issue of tremendous proportions and should be of concern to all."
Sea squirts, poison ivy and other evidence that climate change is altering Connecticut's environment
Comments (0)
Tuesday, July 07, 2009
By Andy Bromage
Sea squirts are smothering Connecticut's shellfish industry.
Sea squirts are smothering Connecticut's shellfish industry.In the film The Day After Tomorrow, global warming looks like hell on Earth.
Polar ice caps melt, causing sea levels to rise and swallow Manhattan in a single tidal surge. Hail stones as big as footballs pummel Tokyo. Twisters rip through Los Angeles, destroying skyscrapers and shredding the Hollywood sign. Then comes a deep freeze, and the world is consumed in a second Ice Age.
In real life, global warming looks like a harmless yellow sea sponge. Non-native sea squirts, also known as Tunicate or sea pork, are proliferating in Long Island Sound and elsewhere as water temperatures rise. Marine scientists at the University of Connecticut found that warmer winters are causing the invasive invertebrates to explode in population. Sea squirts reproduce rapidly and compete with shellfish for food and space, threatening Connecticut's shellfish industry.
Like sea squirts, the early signs of global warming mostly fall into the non-life-threatening category: fast-spreading poison ivy and clinging kudzu vines. But that's just a preview of what's to come.
"What's happening today is a mild annoyance. This is nothing compared to what's around the corner," says Brenda Ekwurzel, a climate scientist with the Union of Concerned Scientists in Washington, D.C.
The U.S. House just passed, and the Senate will debate, the most sweeping climate change bill in a generation, one that would cap carbon emissions — a huge step toward curbing greenhouse gases.
Should smokestacks belch on unabated, Ekwurzel predicts, Connecticut's own day after tomorrow will feature fire ants, blood-sucking insects and suffocating summers as hot and humid as Georgia's.
Ekwurzel was a staff hydrologist at the Connecticut Department of Environmental Protection in the late 1980s (she lived in New Haven) and says signs of global warming are subtle, but there.
Conclusively linking these events to man-made climate change is tricky (see sidebar), but leading climatologists say they are consistent with what they'd expect a warming planet to do. Here are five clues that global warming has arrived in Connecticut. Senators, take note:
It's the Heat, Stupid
Temperatures in the northeast (Pennsylvania to Maine, including Connecticut) have risen sharply in the last 40 years, according to a 2007 study by the Union of Concerned Scientists.
Overall, the mercury's up 1.5 degrees on average since 1970, with the winter average being 4 degrees higher. The amount of ground covered by snow for longer than 30 days has decreased significantly, threatening cross-country skiing, snowball fights — and sugar maples. Warmer weather will push the trees north into Canada, scientists fear, decimating New England's maple sugar industry.
The Fish Switch
So long lobster, hello blue crab! The fish species inhabiting Long Island Sound are undergoing something of a sea change, says Peter Auster, a marine sciences professor at UConn.
Cold-water species like winter flounder, windowpane flounder and Atlantic herring are declining in number. Fish that like warmer climes, like weakfish, are on the rise, he says.
The die-offs that decimated Sound lobsters in 1999 and before can't be linked concretely to global warming, but it's hardly unthinkable, Auster says. In their place, blue crabs, which like warmer water, are reproducing like mad. "Between increased temperatures and stress on lobsters — warming certainly contributed to that."
One variable that complicates the theory: fishing. "The problem with working on fish is there's something called fishing going on," Auster says. "What's climate change and what's fishing is hard to say."
Attack of the Vines!
They call it "the vine that ate the south," but it must still be hungry. Once relegated to the south, kudzu vines have stretched into northern states too, including Connecticut. These invasives from Asia can grow up to a foot a day and strangle everything in their path.
Don't be fooled by the pretty flower they shoot up: kudzu kills other plants by smothering them and can get so heavy it uproots trees by the force of its weight. Kudzu now infects 2.5 million acres of farmland, fields and forests in the American south.
Scientists blame warmer, wetter weather for its arrival in the Nutmeg State. "It's a very voracious vine, so it can outcompete other vegetation," says Ekwurzel.
Ivy League
Poison ivy's going gangbusters as the globe heats up. Scientists at the Connecticut Agricultural Experiment Station in New Haven say poison ivy is spreading in the state, and some researchers think global warming is the culprit. A widely quoted 2006 study by Jacqueline E. Mohan of Duke University suggests that higher CO2 levels are causing poison ivy to spread and become more toxic. In her experiment, ivy exposed to higher CO2 levels averaged 149 percent faster growth than control plants.
See the Sea Squirts
In 2002, UConn scientists studied whether climate change was to blame for the growth of invasive sea squirts in Long Island Sound. The harmless-looking invertebrates outcompete economically vital shellfish like clams, mussels and oysters and smother other organisms. Left unchecked, they could have a devastating impact on shellfishing in the Sound.
And the warmer the water, the worse they get.
Scientists studied native species against invasive ones from 1991 to 2002 at Avery Point near Groton. They found that in the year after the warmest winter (1991), invasive growth was twice that of native squirts. By contrast, after the coldest winter (1994), the native ones outgrew the invasive sea squirts 5-to-1.¦
An Inconvenient Truthteller
Sandra Shumway believes in global warming. She also believes it's become a catchphrase scientists use for any number of unexplained biological and ecological phenomena. And something they throw around to attract research dollars.
"It makes it more relevant to granting agencies," says Shumway, a marine sciences professor at UConn.
Shumway, whose expertise is shellfish biology and the impacts of harmful algae on shellfish aquaculture, says linking ecological changes to climate change is a "leap of faith" some scientists make too easily.
"There are any number of factors that can alter environment and biological activities, temperature certainly being among them. It's not the only thing," she says. "That is not to say global warming isn't an issue of tremendous proportions and should be of concern to all."