NASA/Marshall Earth Science 1997 Stories
1997 Science Highlights Preview: Earth Systems Science Science From Space
[Lightning From Space][Seeing the Past from Space]
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.
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|
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|
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!!!
|The Value of Real-Time Lightning Detection||February 5, 1997|
|Launch of the Lightning Imaging Sensor aboard the Tropical Rainfall Measurement Mission||November 1997|
|Lightning Research at NASA/Marshall and the GHCC|
|Optical Transient Detector Home-Page|
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!!!
Authors: Dr. John Horack, Dave Dooling
Curator: Bryan Walls
NASA Official: Dr. Gregory S. Wilson, Director
Last updated November 19, 1997