NASA Investigations of the Greenhouse Effect
Over the past 30 years, a number of satellite missions have been launched to obtain the data about Earth's radiation budget that are critical to understanding the greenhouse effect. Some of these missions are listed in the accompanying table.
Another very important aspect of greenhouse investigations has been the development of models. A number of climate models have been developed by NASA, and one of the most detailed is a General Circulation Model (GCM) developed by the Goddard Institute for Space Studies (GISS) in New York City. A GCM uses extremely high-speed computers to solve the basic equations governing atmospheric motions and processes by numerical techniques. The GISS group, using its model, predicted that the annual global temperature would reach a new record high sometime during the first three years of the 1990's. Indeed, that record was reached in 1990. However, in June 1991, the Mount Pinatubo volcano erupted and sent 25 to 30 million tons of sulfur dioxide into the stratosphere. There, the sulfur dioxide reacted with water vapor to produce a long-lasting haze of sulfuric acid droplets.
The GISS group then inserted the new information into the model, estimated how much sunlight the Pinatubo aerosol cloud would block, and predicted that the global temperature would drop about 0.3 degree C. Again, the predicted change actually occurred. Although these successful climate predictions are encouraging, most scientists agree that much remains to be done to improve climate models before we will be able to predict future climate in a credible manner.
An important need in the further development and verification of climate models is the acquisition, assembly, and analysis of reliable climate data. The highly-accurate, self-consistent, and long-term data sets that will be acquired by the Earth Observing System (EOS), as part of NASA's Mission to Planet Earth with a series of satellite launches beginning in 1998, are designed to fulfill that need.
Over the past 30 years, a number of satellite missions have been launched to obtain the data about Earth's radiation budget that are critical to understanding the greenhouse effect. Some of these missions are listed in the accompanying table.
Another very important aspect of greenhouse investigations has been the development of models. A number of climate models have been developed by NASA, and one of the most detailed is a General Circulation Model (GCM) developed by the Goddard Institute for Space Studies (GISS) in New York City. A GCM uses extremely high-speed computers to solve the basic equations governing atmospheric motions and processes by numerical techniques. The GISS group, using its model, predicted that the annual global temperature would reach a new record high sometime during the first three years of the 1990's. Indeed, that record was reached in 1990. However, in June 1991, the Mount Pinatubo volcano erupted and sent 25 to 30 million tons of sulfur dioxide into the stratosphere. There, the sulfur dioxide reacted with water vapor to produce a long-lasting haze of sulfuric acid droplets.
The GISS group then inserted the new information into the model, estimated how much sunlight the Pinatubo aerosol cloud would block, and predicted that the global temperature would drop about 0.3 degree C. Again, the predicted change actually occurred. Although these successful climate predictions are encouraging, most scientists agree that much remains to be done to improve climate models before we will be able to predict future climate in a credible manner.
An important need in the further development and verification of climate models is the acquisition, assembly, and analysis of reliable climate data. The highly-accurate, self-consistent, and long-term data sets that will be acquired by the Earth Observing System (EOS), as part of NASA's Mission to Planet Earth with a series of satellite launches beginning in 1998, are designed to fulfill that need.
Original source : http://www.maui.net/~jstark/nasa.html
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