Satellite data coupled with new modeling is found to efficiently predict drought and wildfire risk
Advanced scientific instruments in orbit around the planet are capable of tracking stocks of groundwater resources, which researchers are utilizing to develop more accurate predictions system for drought and the risks that it brings months in advance. In 2002, a joint space project was launched between Germany and America, the Gravity Recovery and Climate Experiment (GRACE) mission installed a pair of satellites into polar orbit with an aim to map the Earth’s gravitational field.
The twin satellites work in collaboration to map variations in the Earth’s gravity. The instruments are sensitive enough to reveal micro fluctuations in the Earth’s gravitational field, as changes in mass underneath cause them to speed up and slow down ever so slightly. Scientists at Australian National University’s (ANU) Research School of Earth Sciences was able to measure changes in the amount of water stored in the ground, as larger masses of water will result in a slightly larger gravitational pull.
Though the GRACE, satellites were recently decommissioned, in their time of operation they collected a wealth of useful data for scientists to pore over. 2012 study revealed an unsettling pattern of the Earth’s groundwater reserves on the decline, which provided with clear picture of how much water was present at various depths. Furthermore, researchers analyzed how different kinds of vegetation around the world are able to access the groundwater at different depths, information they were then able to use to predict the state of that same vegetation months down the track.
The researchers describe the accuracy with which the satellites can measure the presence of water on Earth as ‘mind-boggling’ and ‘unprecedented.’ Combined with computer modeling, the scientists say it can help simulate the cycles of plant growth and water distribution, helping them predict declining conditions of grazing areas, crops and forests in advance and also indicate areas at heightened risk of wildfires. The research was published in the journal Nature in January 2019.