Space is the premier vantage point for viewing the Earth and studying its complex climate and weather processes. In 1997, scientists from NASA/Marshall and the Global Hydrology and Climate Center (GHCC) made significant advances in our understanding of the Earth's weather and climate as a large-scale, complex system.
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Urban Heat Islands
Anyone who drives from the city into a park will tell you
that life's cooler around trees. In May, scientists performed a unique study
in Atlanta to determine the effects of urbanization, including tree loss,
on local weather and climate. Flying aboard a NASA jet, the Airborne Terrestrial
and Land Acquisition Sensor (ATLAS) made noon and midnight temperature maps
of the Atlanta area. In urban areas, parking lots, buildings, and other
manmade structures were observed to raise local temperatures by 5 °F
or more.
These "urban heat islands," which are visible
in thermal imagery from space, can raise energy and health care costs. By
studying how urbanization affects weather and climate on a local scale,
scientists hope to learn how to plan cities to be weather-friendly -- by
strategic planting of trees, for example -- and thus lower utility bills,
conserve energy, and make municipal growth sustainable. They can also understand
better the local contributions to global warming.
Learn more about Project Atlanta and Urban Heat Island Research at NASA/Marshall and the GHCC!!!
 Hot 'Lanta: NASA, school
kids team to study how trees help cities keep their cool |
May 8, 1997 |
| Project
Atlanta at NASA/Marshall and the Global Hydrology and Climate Center |
A Complex Atmosphere and Global Warming
For nearly 20 years, scientists at NASA/Marshall and
the GHCC have studied the temperature of the Earth's atmosphere from space
in an attempt to understand the potential magnitude and impact of global
warming. While the temperature at the Earth's surface continues to rise,
the satellite measurements show atmospheric temperatures are steady or falling,
with major excursions produced by natural phenomena like large volcanic
eruptions and El Niño. This apparent discrepancy had been the source
of much controversy.
However, in 1997, scientists from the GHCC discovered that
the low humidity of the tropical free troposphere plays a previously overlooked
central role in the dynamics of the atmosphere. This region of low humidity
allows much of the infrared radiation to escape from the Earth and cool
the atmosphere. Computer models do not accurately handle the processes which
control the humidity in this region, which are related to rainfall. Therefore
the overall signature of any manmade global warming is likely to be much
more complex than originally thought.
Learn more about measuring the Earth's temperature from space, and global warming research at NASA/Marshall and the GHCC!!!
| Is Earth's Temperature
Up or Down or Both? |
February 5, 1997 |
| Global Climate Monitoring:
The Accuracy of Satellite Data |
March 12, 1997 |
| How Dry is the Tropical
Free Troposphere? |
July 14, 1997 |
| Accurate "Thermometers"
in Space: The State of Climate Measurement Science |
October 6, 1997 |
Lightning from Space
In a unique
study in 1997, NASA and GHCC scientists demonstrated conclusively the value
of real-time lightning detection to provide added knowledge to the weather
forecaster in the identification and warning of thunderstorm hazards. Spaceborne
sensors can detect all the lighting in a storm, not just the cloud-to-ground
strikes, greatly enhancing one's insight into developing severe weather.
In November 1997, the Lightning Imaging Sensor, our next-generation space-based
lightning detector, was launched aboard the Tropical Rainfall Measurement
Mission, a joint U.S.-Japanese research effort. LIS is the next step towards
realization of a Lightning Mapping Sensors in geostationary orbit to provide
continuous, real-time lightning detection coverage of nearly the entire
globe.
Learn more about lightning measurements from space from space, and severe weather research at NASA/Marshall and the GHCC!!!
Seeing the Past from Space
Using remote sensing imagery over
the unexplored jungle of northern Guatemala, a research team led by NASA
and GHCC scientist Dr. Tom Sever
has located a Mayan archaeological site which might prove to be the legendary
"Site Q," a center of Mayan culture, commerce, and civilization.
After seeing potential ancient Maya causeways and other cultural features
in satellite images, the research team visited the site in 1996 and 1997.
Whether this actually is Site Q will be determined soon from translations
of hieroglyphics . The Maya, who mysteriously disappeared in just 20 to
100 years, once had a population density nearly equivalent to today's Europe.
Their disappearance may be connected with a change in the local water table
brought on by significant depletion of the tropical rain forest. The region
again is experiencing widespread deforestation to support agriculture, and
GHCC scientists theorize history may be about to repeat itself. By studying
the Maya from space, we may learn how to avoid similar problems in the future
here on Earth.
Learn more about Space Archaeology at NASA/Marshall and the GHCC!!!
| NASA Helps
Find Mayan City |
April 7, 1997 |
| Space
Archaeology Research!!! |
| 1997 Highlights Physics and Astronomy |
1997 Highlights Microgravity Science |
Last updated November 19, 1997