Hey Deniers. Corn Called. CO2 Not all That Good for Plants.
April 12, 2012
Global warming may initially make the grass greener, but not for long, according to new research results.
The findings, published this week in the journal Nature Climate Change, show that plants may thrive in the early stages of a warming environment but then begin to deteriorate quickly.
“We were really surprised by the pattern, where the initial boost in growth just went away,” said scientist Zhuoting Wu of Northern Arizona University (NAU), a lead author of the study. “As ecosystems adjusted, the responses changed.”
Ecologists subjected four grassland ecosystems to simulated climate change during a decade-long study.
Plants grew more the first year in the global warming treatment, but this effect progressively diminished over the next nine years and finally disappeared.
The research shows the long-term effects of global warming on plant growth, on the plant species that make up a community, and on changes in how plants use or retain essential resources like nitrogen.
“The plants and animals around us repeatedly serve up surprises,” said Saran Twombly, program director in the National Science Foundation (NSF)’s Division of Environmental Biology, which funded the research.
“These results show that we miss these surprises because we don’t study natural communities over the right time scales. For plant communities in Arizona, it took researchers 10 years to find that responses of native plant communities to warmer temperatures were the opposite of those predicted.”
A hard freeze has wiped out a big portion of the cherry crop in Northwest Michigan this spring. The area produces more than half the state’s cherries that end up in desserts, juice and as dried fruit.
An historic early warm-up in March left fruit trees vulnerable to frost once the weather turned cooler again.
Temperatures broke records for the month of March across the Great Lakes region.Climate researchers say there’s never been anything like it going back more than a hundred years.”We’re seeing history made before our eyes at least in terms of climatology.”
Jeff Andresen is the state’s climatologist and professor of geography at Michigan State. “And in some ways if we look at where our vegetation is and how advanced it is, it’s probably a month ahead of where it typically is.”
Andresen is careful to point out that this year’s early warm-up is an extreme weather event.
He says it far outpaces the previous warmest March on record in 1945. He can’t say it’s a direct result of climate change. But it fits the predicted long term pattern of change that includes extreme fluctuations.
During one period, there were several straight days of above 80 degree daytime highs and nighttime temperatures in the 60’s.
Philippe Coquard could use some sleep. He’s the co-owner of the Wollersheim Winery in Prairie du Sac, Wisconsin. And he’s been up two nights in a row. He blames it on the weather.
PHILLIPPE COQUARD: The month of March was like summer, which we never see that in Wisconsin. And everybody is so happy and it feels like summer. Well, it’s not good to us.
CORNISH: That’s because Coquard’s 27 acres of grapevines budded a month ahead of schedule. And now there’s frost. Coquard and other vineyard and orchard owners in southern Wisconsin are trying to protect those fragile buds. Some build bonfires, some use large tarps. Coquard says his work starts at 1:30 in the morning.
COQUARD: So, soon as the temperature will hit 35 degree Fahrenheit at two feet off the ground, then it triggers an alarm – it calls me in my house. Then I will come to the winery and start our protection equipment.
CORNISH: There are three wind machines positioned at the lowest and therefore coldest part of the vineyards. They keep the cold air moving so the vines don’t freeze. Then there’s the fire dragon. It’s pulled by a tractor.
COQUARD: You start the fire and there’s a big fan that will draw warm air and shoots it right and left. And you will cover almost 60 or 70 feet on each side of that device.
CORNISH: Hot in the rear but still cold at the wheel. Coquard and his assistance take turns driving the dragon all around the vineyard until morning. So far, there’s minimal damage to his vines. But there could be more cold next week. As for now…
COQUARD: I’m due to go take a nap and…
(SOUNDBITE OF LAUGHTER)