NASA’s next Earth observing satellite, the Soil Moisture Active Passive satellite (SMAP), which is all set for a Thursday launch, could help predict droughts and floods all over the world much more effectively than it is now done. The new satellite will use microwaves to measure the amount of moisture in the topsoil for doing so.
Scheduled to be launched from Vandenberg Air Force base in California atop a United Launch Alliance Delta II rocket at 9:20 a.m. EST (1420 GMT) on Jan. 29, the satellite is designed to measure the moisture in the top layer of the Earth’s surface more accurately than ever before, claims the space agency. Being able to measure the moisture content with greater accuracy will help scientists across the world create more accurate weather models and predict floods and droughts with much greater accuracy.
“What the soil measurements will do is improve our weather forecasts, improve our assessments of water availability and also address some issues dealing with long-term climate variability and assessments of the impact of human intervention in the global environment,” Dara Entekhabi, SMAP science team leader, said during a news conference Tuesday (Jan. 27). “All of these come together and it’s the metabolism, how it responds, just like a human body.”
The SMAP observatory has two microwave instruments- an active radar which emits short pulses and listens for reflections and a radiometer which will passively monitor the natural microwave radiations emitted by the Earth. Now, the microwave emissions from the topsoil change according to the amount of moisture held by it and the instruments aboard the SMAP have been specially designed so as to be more sensitive to these emissions.
Though the moisture held by the topsoil accounts for less than 1percent of the total water supply on our planet, its presence or absence plays a huge role in Earth’s water, energy and carbon cycles.
“It’s what is interacting with the terrestrial biosphere, with the vegetation. It’s what is determining how much runoff occurs … how much freshwater there is in the rivers and lakes. It’s a tiny amount, but a very important amount,” SMAP lead scientist Dara Entekhabi, with the Massachusetts Institute of Technology, said during a prelaunch press conference.
The data sent back by this new satellite will change both the manner and the effectiveness of flood and drought forecasts.