Dear Friends/Co-sailors,
For the today's pick section I am sharing with you this new development reported in the New York times. NASA is launching the new satellite Orbiting Carbon Observatory-2 this Tuesday with an aim of tracking the carbon dioxide that does not return back to the Earth.
NY time quotes David Crisp, senior research scientist at NASA's Jet Populsion Laboratory, saying, “Somewhere on earth, on land, one-quarter of all our carbon emissions released through fossil fuel emissions is disappearing...We can’t identify the processes responsible for this. Wouldn’t it be nice to know where?”
Hope you would find this piece of news useful.
Thanks and regards,
Ranjan
NASA Launching Satellite to Track Carbon
An illustration of the Orbiting Carbon Observatory-2, ready
to launch Tuesday to measure atmospheric carbon dioxide. Credit JPL/NASA
By KENNETH CHANGJUNE 29, 2014
On an average day, some 100 million tons of carbon dioxide
is liberated from oil and coal by combustion, wafting into the air. The gas
traps heat in the atmosphere, resulting in the gradual warming that has alarmed
scientists and much of the public.
But only half of the carbon dioxide stays up there; the
other half falls back to earth. While scientists know what happens to half of
that half — it dissolves into the oceans — the rest is a continuing puzzle. It
is taken up by growing plants, but nobody knows exactly where and how.
“Somewhere on earth, on land, one-quarter of all our carbon emissions released
through fossil fuel emissions is disappearing,” said David Crisp, a senior
research scientist at NASA’s Jet Propulsion Laboratory. “We can’t identify the
processes responsible for this. Wouldn’t it be nice to know where?”
Now NASA is launching a satellite to help solve the puzzle.
The satellite, the Orbiting Carbon Observatory-2, is
scheduled to lift off Tuesday morning from Vandenberg Air Force Base in
California. Passing over the North and South Poles at an altitude of 438 miles,
it will observe the same spots every 16 days as the earth rotates beneath.
These repeated measurements will allow scientists to observe
the rise and fall of carbon dioxide with the seasons. They may also figure out
how the balance changes with droughts or floods.
That should give them a better idea of whether the oceans
and land plants will continue to absorb half of the carbon dioxide emissions as
in the past or whether any of these so-called carbon sinks are close to
overflowing, leaving even more gas in the air.
In particular, scientists do not understand how plants have
kept pace with fossil fuel emissions that have nearly tripled since 1960. “Have
you seen a new rain forest spring out of nowhere that wasn’t there before?”
asked Dr. Crisp, the leader of the science team for the mission. “No.”
The orbiting observatory carries a single instrument, to
measure colors of sunlight bouncing off the earth. The relative intensity of
the colors will tell how much carbon dioxide the light beam passed through, and
the spacecraft will take a million measurements a day.
Because of intervening clouds, only a tenth of the
measurements — about 100,000 a day — will prove useful data. Still, that will
dwarf what 150 carbon dioxide measuring stations on the ground are able to
provide. A Japanese satellite is making similar measurements, but with less
precision.
An earlier Orbiting Carbon Observatory mission failed in
2009, when the clamshell nose cone surrounding the spacecraft did not open and
the satellite splashed into the ocean a few minutes after liftoff — a $273
million loss. “That was a heartbreak, utter devastation,” said Ralph R.
Basilio, the project manager for the current mission.
At the end of 2009, the Obama administration decided to
build a nearly identical satellite scheduled for launch in February 2013. But
those plans were disrupted when the same launch failure that had doomed the
first mission occurred again, destroying another NASA satellite, the Glory
mission, in 2011.
The space agency then decided to switch rockets, putting the
new satellite on a Delta 2 rocket, which has long history of successful
launches.
The switch delayed the launching date, and the bigger Delta
2 added to the cost — which totaled $467.5 million this time. The cost also
includes an extra copy of the carbon dioxide measuring instrument, which was
built to ensure against delays if problems arose during testing. That extra
instrument may be flown to the International Space Station to provide another
set of observations.
Levels of carbon dioxide in the air have jumped 40 percent
since the start of the Industrial Revolution, but the amount is still tiny: Of
every million molecules of air, just 400 are carbon dioxide. Over a power plant
or a city where emissions are higher, that number rises by perhaps one molecule
per million. A field of corn stalks at the height of growing season might
reduce the number by a similar amount.
To detect such minute changes, Dr. Crisp said, the parts of
the 300-pound instrument had to be aligned within the width of a human hair.
The scientists think they may also be able to discern a faint infrared
fluorescent glow emitted by plants as they photosynthesize, which could
indicate their health.
The Orbiting Carbon Observatory-2 is part of a busy year for
NASA’s earth sciences division — the second of five launches — reflecting
increased financing for this segment of NASA even as other parts have been
squeezed by tight budgets.
Michael Freilich, director of the earth sciences division,
said, “There is no question that the Obama administration puts a very high
priority on understanding the earth.”
Source: http://www.nytimes.com/2014/06/30/science/nasa-launching-satellite-to-track-carbon.html?_r=0
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