NASA Mission Update: CALIPSO - 10/26/2008

Clouds have forever held the imagination of skygazers who are captivated by their endless beauty and seeming randomness. But clouds, and whats in them, also hold fascination for scientists who seek to understand the many effects they have on life here on Earth.

Hal Maring, Program Scientist, CALIPSO: "Low clouds, which are white, can reflect sunlight and cause cooling of the Earth, and high clouds tend to warm the Earth by absorbing and re-radiating warmth back into the atmosphere."

Launch Announcer: "2-1 We have ignition and we have lift-off of NASAs Calipso/Cloudsat spacecraft."

Since its launch in April 2006, the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation mission, CALIPSO, has provided new insight into the role that clouds play in regulating our climate. As CALIPSO orbits the Earth, its light detection and ranging, or lidar system, emits short pulses of green and infrared light, producing a 300-feet wide snapshot of what's in the atmosphere from top to bottom -- clouds and airborne particles. Snapshots collected along the same orbit are then streamed together to paint a picture of what a vertical slice of our atmosphere looks like.

Hal Maring: "Its basically a large laser range finder, and it shoots light down into the atmosphere. And, its able to detect and measure, clouds in the vertical .Not like a photograph, which tends to be two-dimensional, but gives us vertical curtains of measurements of clouds, i.e., their altitude."

These critical cloud data from CALIPSO are used with information gathered by other satellites in NASAs A-train constellation of Earth-observing spacecraft to quantify just how much sunlight reaches the planet -- and how much gets radiated back into space. This so-called energy budget is a key to documenting and understanding climate change.

Hal Maring: "We have found, it appears as though, the Earth is warming and its warming because of an imbalance or a change in the Earths energy budget."