How can winds be observed by satellites?

Question

What will be the ideal response?

Answer 1

ANSWER: Geostationary satellites positioned above a particular location show the movement of clouds. The direction of cloud movement indicates wind direction, and the horizontal distance the cloud moves during a given time period indicates the wind speed. In addition, a specialized satellite-borne instrument called a scatterometer (a type of radar) can measure surface winds above the open ocean during all kinds of weather by observing the roughness of the sea. From the satellite, the scatterometer sends out a microwave pulse of energy that travels through the clouds, down to the sea surface. A portion of this energy is scattered (bounced) back to the satellite. The amount of energy returning to the scatterometer (called the echo) depends on the roughness of the sea—rougher seas have a stronger echo because they scatter back more incoming energy. Since the sea’s roughness depends upon the strength of the wind blowing over it, the echo’s intensity can be translated into surface wind speed and direction. Surface wind information of this nature can be extremely valuable to the shipping industry, as well as to coastal communities. Hurricanes and other storms over the open ocean can be carefully monitored to see how their winds are changing. And incorporating sea surface wind information into computer forecast models may have the benefit of improving weather forecasts.