Sunday, 12 August 2012

Climate stuff from the fortnight 30/7 - 12/8/12

Salmon are staying out at sea for another year, to fatten up their gonads, before swimming inland to breed.
This means smaller populations to fish, but bigger adults, which is what the fishers want.
These changes have been driven by temperature changes, augmenting the food web, meaning the salmon are going hungry, in the autumn - the critical time for gonad maturation.
And on the other coast, grizzlies are getting more and more stressed from hunger.

About 40,000 shovelnose sturgeons have died in Iowa, because of temperatures up to 38 degrees Celsius.
The US has been suffering, this year, with terrible drought conditions, which climatologists say has been exacerbated by the climatic effects of fossil-fuel combustant pollution.
"The fish are victims of one of the driest and warmest summers in history. The federal U.S. Drought Monitor shows nearly two-thirds of the lower 48 states are experiencing some form of drought, and the Department of Agriculture has declared more than half of the nation's counties — nearly 1,600 in 32 states — as natural disaster areas. More than 3,000 heat records were broken over the last month."
[video] 2012 Drought Update:
'New NASA study links current extreme summer events to climate change'

'Greenland loses ice in fits and starts'
There's a lot of ice on Greenland; and there's even more on Antarctica; but because we know so little about how they behave, we can't formulate useful predictions about how they're goignt o melt, as temperatures increase.
We know they're going to contribute to sea-level rises, but we don't know by how much, and when - liek the title says, the melting occurs in fits and starts - caused by fluctuations in ambient water temperature.
Because of this, the meltwater from Greenland and Antarctica was completely left out of the IPCC's 2007 predictions, so all we know is that sea-level rise will be at lest as much as the IPCC predicted.
More research. We need it.

By the way, here's a follow-up from the Greenland surface-melt story:
"On top of the approximately 3 km thick ice sheet in Greenland the temperature is normally around minus 10-15 degrees C in the summer and about minus 60 degrees in the winter. This year, researchers from the Niels Bohr Institute observed temperatures above zero and a significant warming and melting of the upper 1 1/2 meter layer of snow at the NEEM ice core drilling project in northwestern Greenland."
That gives us some idea of quantity -- quite a lot.

52 million years ago, 10 million years after the dinosaurs went extinct, and when atmospheric CO2 concentrations were more than twice as high as they are now (400 ppm), Antarctica was populated by... get this... palm trees!
I remember Walking With Dinosaurs did an episode situated in the Jurassic Antarctic

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