Researchers Hope To Clear Mystery From Clouds
Date: 23-Apr-09
Country: NETHERLANDS
Author: Catherine Hornby
Researchers Hope To Clear Mystery From Clouds Photo: Jerry Lampen/Files
A researcher works on a 3D cloud simulation at the Delft's
University of Technology in the section clouds, Climate and Air Quality in
Delft, in this March 6, 2009 file photo.
Photo: Jerry Lampen/Files
DELFT - Wearing 3-D viewing goggles, scientists peer at virtual pink, blue
and purple clouds billowing in cyberspace at a research laboratory in the
Dutch city of Delft.
By tracking how particles move in and around computer-simulated clouds, they
hope to shed light on one of the unknowns of climate forecasting: how these
masses of water droplets and ice crystals influence changing temperatures.
The research, at Delft University of Technology, was undertaken because of
the growing urgency for scientists to improve ways of forecasting climate
change.
Besides the Dutch scientists' work, a multi-million-euro satellite project
funded by the European and Japanese space agencies will be launched shortly
to help demystify clouds, which are also a source of inspiration for
thousands of amateur cloud-spotters who post their comments and photos
online.
Researcher Thijs Heus, a former student at the laboratory, explained that he
used the simulations to chart data such as the speed, temperature and
lifespan of clouds.
"We number the clouds and we track them from their infancy through their
entire life cycle," he said.
"We can also give them color to see if dust particles are moving up or down
within and around the clouds," Heus added, demonstrating ways to observe
clouds in more detail by magnifying their virtual images on screen.
Using powerful computer technology and satellite data, the scientists at
Delft hope to gain a more accurate picture of how clouds react to climate
change.
"There is enormous uncertainty about what clouds will do, and how they will
respond to a changing climate and that is a major impediment for climate
predictions," said Harm Jonker, associate professor at the university.
SOURCE OF UNCERTAINTY
Projections of how much the earth's temperature will rise in the next
century vary from 1.1 to 6.4 degrees Celsius (from 2 to 11.5 degrees
Fahrenheit), with the effect of clouds remaining one of the main sources of
uncertainty, the U.N. Climate Panel found in its 2007 climate assessment
report.
Jonker said it was unclear, for example, whether there would be more or
fewer of low clouds such as cumulus in warmer conditions, which would affect
the rate of global warming because of their role in reflecting sunlight away
from the earth.
"In a warmer climate, if there is more evaporation, that could lead to more
of the lower clouds, which could diminish the effects of climate warming,"
said Jonker.
He added warm air could hold more water vapor than cold air before it formed
clouds, so there might be fewer low clouds as the earth heated up, which
would accelerate global warming.
Rising sea levels and increased risk of droughts, flooding and species
extinction are some of the likely effects of global warming, caused mainly
by emissions of greenhouse gases from burning fossil fuels, the U.N. Climate
Panel has projected.
European and Japanese space scientists have turned their attention to clouds
because of the pressing need for research.
A 350-million-euro satellite project, due for launch in 2014, aims to
improve understanding of the role they play in climate regulation.
The project, known as EarthCARE, is being assembled mainly by the Astrium
unit of the European aerospace group EADS and combines the technology of
existing cloud observation satellites with new instruments for a more
accurate picture.
"It's much more complex then anything that's flying at present," said
Stephen Briggs, head of the Earth Observation, Science, Applications and
Future Technologies Department at the European Space Agency.
"The difficulty with clouds is that you can't see into them, so you have to
find ways of looking into their three-dimensional structure, such as with
radar systems."
CLOUD OF THE MONTH
Advances in research are followed closely by cloud enthusiasts who spend
their leisure time looking out for unusual varieties and learning about
their effect on the planet.
"We believe that clouds are unjustly maligned and that life would be
immeasurably poorer without them," says the Cloud Appreciation Society, a
club for spotters, on its website, where it regularly posts a "cloud of the
month."
The wispy high cirrus, the ominous cumulonimbus and the fluffy cumulus have
all held the title and have led to heated debate in Internet chat forums.
Thousands of people capture unusual or striking clouds on camera and share
them online.
"High cirrus thickened up to put on a strange show over Phoenix this
evening," said U.S. spotter Mike Lerch in a chat forum, before posting
dramatic shots of the spidery high clouds in the skies above Arizona.
Enthusiasts are keen to challenge negative attitudes to clouds, which have
spawned sayings such as "a dark cloud on the horizon" and "even the darkest
cloud has a silver lining."
"I thought it was about time someone stood up for the clouds because too
many people complain about them," said Gavin Pretor Pinney, author of "The
Cloudspotter's Guide."
"They are rather chaotic things, difficult to predict, difficult to fully
understand, but the facts are emerging that they play a crucial and
essential role in regulating and affecting the temperatures on the planet."
(Editing by Andrew Dobbie)
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