More systematic, integrated use of GPS techniques could lead to better information about the highly variable features of the hydrologic cycle and more.

Atmospheric water vapor is the dominant greenhouse gas in the earth's atmosphere, and so quantifying the feedback of water vapor in global warming is therefore of paramount importance. This feedback is also crucial for other feedback processes, such as snow-sea ice and clouds, that also play a significant role in climate. The lack of detailed knowledge of the hydrological cycle thus is a major limiting factor toward a better understanding of the earth's climate system. The inaccuracy is substantial and concerns practically all aspects of the ...