We discuss and comment on the role agriculture will play in the containment of the CO2 problem and address protocols for terraforming the planet Earth.
A model farm template is imagined as the central methodology. A broad range of timely science news and other topics of interest are commented on.
Saturday, March 9, 2013
Ice Sheet Flow Research
What I find most interesting was how a really modest increase in
climate was able to feed back into ice shelf mobility. The
additional warmth produced larger surface melting on the ice sheets
and this melt water increases penetration to the bottom of the ice
sheet affecting its effective viscosity. It is clearly quick and
It is also a warning that a sudden sharp temperature rise of say two
degrees or more will dump huge amounts of ice into the ocean very
quickly. This is likely to happen as we pass through the Sirius
cluster in the next fifty thousand years or so.
Another question I would like to have answered is just how much
surface ice loss occurred last summer. Was it enough to make the
year's ice signature disappear from the ice core record? It clearly
has not happened often but it may be a significant source of error
when it does happen.
Let us not forget that the Greenland ice sheet is a remnant of an ice
sheet comparable to the Antarctic sheet. Thus modest changes will
have far larger effects to the whole sheet making it harder to
correct for by changing locations.
Flow of research on
ice sheets helps answer climate questions
Just as ice sheets
slide slowly and steadily into the ocean, researchers are returning
from each trip to the Arctic and Antarctic with more data about
climate change, including information that will help improve current
models on how climate change will affect life on the earth, according
to a Penn State geologist.
"It is not just
correlation, it is causation," said Richard Alley, Evan Pugh
Professor of Geosciences. "We know that warming is happening and
it's causing the sea levels to rise and if we expect more warming, we
can expect the sea levels to rise even more."
Alley, who reported on
his research Feb. 16 at the annual meeting of the American
Association for the Advancement of Science in Boston, has studied the
movement of ice sheets in Greenland and the Antarctic over the years.
One way researchers are measuring climate change is by collecting
data on how fast ice sheets are flowing toward the sea and comparing
those speeds over time, according to Alley.
Ice sheets are
miles-thick, continent-wide layers of ice that spread toward the
oceans. The researcher said that rising air temperature speeds
melting in warmer parts of ice sheets, contributing to sea-level
rise. Ocean warming can melt the floating ice shelves that form in
bays and fjords around ice sheets.
This lowers the
friction with the rocky coast, allowing non-floating ice to flow more
rapidly into the ocean and raise the sea level, Alley said.
However, when the
climate is warmer, water levels build up beneath the ice and allow it
to float higher above the rocks, cutting down on the friction.
Researchers have reported that the speed of the ice shelf movement
has nearly doubled in recent years.
melting also leads to sea level rises, Alley said. The more quickly
the ice can enter the sea, causing sea levels to rise. The areas of
uncertainty are how much the sea levels will rise and how soon it
will happen, the researcher said.
have projected a range of probabilities about how high and how
quickly the seas will rise, Alley said. Now, they are trying to
better understand whether sea level rise will happen gradually, like
a dial, or abruptly, like a switch, he said. "If you turn a
dial, such as a dimmer on an overhead light, you can change the
brightness gradually, but with a switch, it is either on or off,"
Most planners expect
the sea level to rise gradually. If sea levels do change minimally
and slowly, there will still be costs, but people and governments
will have more time to deal with the problems -- for instance, by
building walls and replenishing beaches with sand.
However, if sea levels
rise fast and suddenly, the cost to fix the damage and prepare for
further problems will increase rapidly, according to Alley.
"If the sea rises
faster, then it can be much more expensive," said Alley. "The
prices will go up much faster than the sea levels." Alley
expects future research projects will help scientists better predict
the rate and size of sea level rise.
"The great thing
is that this is a wonderful period of discovery and exploration in
places like Greenland and the Antarctic," said Alley. "In
the next few year we'll see even more progress."