Research and Application News
NASA balances water budget with new estimates of liquid assets
07 July 2015
Many pressing questions about Earth's climate revolve around water. With droughts and flooding an ongoing concern, people want to know how much water is on the move and where it is going. To help answer those questions, a new NASA study provides estimates for the global water cycle budget for the first decade of the 21st century, taking the pulse of the planet and setting a baseline for future comparisons.
The water cycle is the catch-all phrase to describe the movement of water - in its different forms, e.g., liquid, gas and solid - around the planet. It includes freshwater used in households and for agriculture, so any changes to the patterns of where rain and snow occur due to the changing climate may have huge impacts for communities worldwide.
The study is a rigorous accounting of the movements of Earth's water from 2000 to 2010, and the first to rely solely on satellite observations and data-integrating models. The new estimates were derived simultaneously with estimates for the amount of energy from the sun available to heat and move water. A hotter day outside means, for example, that more water evaporates from the soil, plants or the ocean, so putting a number on the amount of heat energy helps scientists put a number on the amount of water that lifts into the atmosphere and is then transported by winds around the world. Assessing these two major components of Earth's climate system is the first step for evaluating how patterns of water and energy may be affected by climate change.
Image credit: NASA - The Water Cycle