Clouds and Climate Change
We must also determine to what extent resulting changes in cloud patterns will affect climate as a result of their effects on Earth's "energy balance." If we measure the total amount of solar energy Earth receives from the sun, then we deduct from that number the total amount of sunlight reflected and the heat emitted from Earth, then we arrive at a number referred to as Earth's "energy budget." Because global measurements to date suggest that the amount of incoming radiant energy is roughly equal to the amount that is outgoing, we say there is an "energy balance." But a small percentage change in cloud cover could have a significant effect on Earth's energy balance. A key to predicting climate change is to observe and understand the global distribution of clouds, their physical properties (such as thickness and droplet size), and their relationship to regional and global climate. Because clouds change rapidly over short time and space intervals, they are difficult to simulate in computer models and, therefore, their contribution to climate change is difficult to quantify. Improving our understanding of clouds and refining our predictive models of their behavior will also aid weather forecasting. Current global change models are hampered by insufficient understanding of certain fundamental physical processes. NASA's Terra spacecraft will obtain a variety of precise measurements of cloud properties to feed improved climate models. Terra will yield improvements in our knowledge of cloud water droplet and ice crystal content, as well as how the feedback loops between Earth's air, land, and ocean work from day to day. next: Surface-Based and Satellite Observations |
|
Subscribe to the Earth Observatory About the Earth Observatory Contact Us Privacy Policy and Important Notices Responsible NASA Official: Lorraine A. Remer Webmaster: Goran Halusa We're a part of the Science Mission Directorate |