But officials said the flights also will serve as a partial replacement for one satellite: NASA's Ice, Cloud and Land Elevation Satellite, known as ICESat.
Less ice on rivers, lakes and the sea will lead to more evaporation, probably increasing cloud cover at mid-levels, which should have a cooling effect.
In China, they use artillery shells, rockets and airplanes to spray existing cloud systems with silver iodide, a compound that triggers moisture in the clouds to form ice crystals, which then fall to earth as snow or rain.