Posted on 09/04/2001 9:12:59 AM PDT by sam_paine
Date: Tue, 4 Sep 2001 11:20:11 -0400 (EDT) Subject: EARTH'S BECOMING A GREENER GREENHOUSEDavid E. Steitz Headquarters, Washington Sept. 4, 2001 (Phone: 202/358-1730)
Lynn Chandler Goddard Space Flight Center, Greenbelt, Md. (Phone: 301/286-2806)
Harvey Leifert American Geophysical Union, Washington (Phone: 202/777-7507)
Colin Riley Boston University, Boston (Phone: 617/353-5386)
RELEASE: 01-178
EARTH'S BECOMING A GREENER GREENHOUSE
NASA satellite data suggest that for more than two decades there's been a gradual greening of the northern latitudes of Earth.
Researchers confirm that plant life seen above 40 degrees north latitude, which represents a line stretching from New York to Madrid to Beijing, has been growing more vigorously since 1981. One suspected cause is rising temperatures possibly linked to the buildup of greenhouse gases in our atmosphere.
Over this same time period, parts of the Northern Hemisphere have become much greener and the growing season has increased by several days. Further, Eurasia appears to be greening more than North America, with more lush vegetation for longer periods of time.
The results of this NASA-funded research will appear in the September 16 issue of the Journal of Geophysical Research - Atmospheres.
"When we looked at temperature and satellite vegetation data, we saw that year-to-year changes in growth and duration of the growing season of northern vegetation are tightly linked to year-to-year changes in temperature," Liming Zhou of Boston University said. The area of vegetation has not extended, but the existing vegetation has increased in density.
The authors also looked at the differences in vegetation growth between NorthAmerica and Eurasia, since the patterns and magnitudes of warming are different on the two continents.
The greenness data from satellites were strongly correlated with temperature data from thousands of meteorological stations on both continents. The Eurasian greening was especially persistent over a broad area from central Europe through Siberia to far-east Russia, where most of the vegetation is forests and woodlands. North America, in comparison, shows a fragmented pattern of change notable only in the forests of the East and grasslands of the upper Midwest.
Dramatic changes in the timing of both the appearance and fall of leaves are recorded in these two decades of satellite data. The authors report a growing season in Eurasia that is now nearly 18 days longer. Spring arrives a week early and autumn is delayed by 10 days. In North America, the growing season appears to be as much as 12 days longer.
The researchers used a temperature data set developed from the Global Historical Climate Network. Dr. James Hansen, of NASA's Goddard Institute for Space Studies in New York, developed this data set and said, "The data were compiled from several thousand meteorological stations in the United States and around the world. The stations also include many rural sites where the data are collected by cooperative private observers."
Scientists believe the results indicate a greener greenhouse. "This is an important finding because of possible implications to the global carbon cycle," said Ranga Myneni of Boston University. "However, more research is needed to determine how much carbon is being absorbed, and how much longer it will continue."
Carbon dioxide is a main greenhouse gas and is suspected of playing a role in rising global temperatures. If the northern forests are greening, they may already be absorbing carbon -- a process that can impact global temperature changes.
Researchers used the Normalized Difference Vegetation Index (NDVI) to help determine the "greening" of plant life. Dr. Compton Tucker, of NASA's Goddard Space Flight Center, Greenbelt, Md., is a co-author of the report and developed NDVI to analyze spectral data collected by orbiting weather satellites.
This work was made possible through funding by NASA Headquarters' Earth Science Enterprise, a long-term research program dedicated to understanding how human-induced and natural changes affect our global environment.
Additional information is available on the Internet at: http://cybele.bu.edu http://www.gsfc.nasa.gov/topstory/20010904greenhouse.html
I Love how you converted this greenhouse issue into a pro-life one!! ;-)
I find it amazing that will all this additional "greening" we are fussing about CO2 so much ... I mean, what do they want to do, starve the trees next?
God Bless!
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to the petition for the unborn (and ask others to do likewise)
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http://www.freerepublic.com/forum/a3b7c063605a8.htm
So let me see if I understand this. There is more carbon dioxide in the air, so the planet warms. The planet warming causing more forests growth in more places. The extra forest growth absorbs carbon.
They forgot the next few steps. The extra forest absorbs the extra carbon. Because there is less carbon dioxide in the air, the planet cools. Self regulating.
Hmmm, tell me about global warming again...
This is because during the 18th and 19th century, vast sections of forest was cleared in North America by settlers for farmlands. Now that farming has gotten much more efficient, we can grow much more food with much less acerage. The result is that most of these small farms have now been allowed to grow back to their original state. Just look out the window next time you fly from the East Coast to say, Chicago. It is virtually a never-ending blanket of green, broken up by a few towns and housing developments.
Oh, yes, notice how they don't say the the impact is a positive one. Or at least one opposite of the scare-mongering one. Maybe in a few years we can talk about the coming ice age once again.
For the Maples want more sunlight, but the Oaks ignore their pleas......"
Nah, it's just because all the soccer moms keep nagging the soccer dads to water the lawn...
About 10 years ago Rush Limbaugh read a paper from some high falutin' dendronologist that unequivocally stated that we have substantially more forest today than we did 200 years ago. Nothing has changed.
The article is crap anyway, since outside of the urban cores, the climate is getting cooler fast.
Don't say that to those of us in Texas. Particularly Dallas, being an urban core. It's supposed to be around 95 degrees about this time of the year. My thermometer says 74 right now. Not that I'm complaining. I like the cooler weather.
There is no global warming.
There is a lot more concrete than there used to be around these meteorological stations.
20 year records from these stations shows slight "warming"
Satellite temperature readings which do not have this bias due to concrete show no change whatsoever in the last 20 years.
The truth can be found here:
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