Research Earth Observations Satellites provide the potential for observing changes of the Earth system on a global scale. A major task at GISS is to define which satellite observations are needed in the 1990s and to study how satellite data relates to and supports data acquired using more conventional techniques. Satellite observations are analyzed to obtain information on the Earth's surface, atmosphere and, especially, global cloud systems.
Clouds are a great source of uncertainty in predicting future climate.
Clouds are potentially the most powerful feedback mechanism in the climate system, but we are not yet even certain whether they are a positive feedback which will enchance future greenhouse warming, or a negative feedback. Comparing Temperatures from Different Monthly-Mean Datasets James Hansen et al.