News | May 21, 2006
Pacific Climate Calm
The latest remote sensing data from NASA's Jason satellite show near normal conditions across the equatorial Pacific Ocean. As we enter the Atlantic Ocean hurricane season, there are currently no visible signs in sea surface height of either El Niño or La Nña. The image represents data collected and composited over a 10-day period, centered on May 21, 2006. The height of the water relates to the temperature of the water, an indicator of the changing amount of heat stored in the ocean. As the ocean warms, its level rises; and as it cools, its level falls. Yellow and red areas indicate where the waters are relatively warmer and have expanded above normal sea level, green (dominating this image) indicates near normal sea level, and blue and purple areas show where the waters are relatively colder and the surface is lower than normal sea level.
The Jason satellite carries a dual-frequency radar altimeter. This instrument beam microwave pulses-at 13.6 and 5.3 Gigahertz, respectively-downward toward the Earth. To determine the ocean's height, the instrument precisely measures the time it takes for the microwave pulses to bounce off the surface and return to the spacecraft. This measure, multiplied by the speed of light, gives the range from the satellite to the ocean surface. The U.S. portion of the Jason mission is managed by JPL for NASA's Science Mission Directorate, Washington, D.C. Research on Earth's oceans using Jason and other space-based capabilities is conducted by NASA's Science Mission Directorate to better understand and protect our home planet.
Please visit the Earth Observatory site for additional information.