While the world is made up of 75% water, only a small portion of it is available and used in daily life.Limited information, and in some cases, no information at all, about the world’s active river systems can prove detrimental in a world already facing a water crisis. To identify these hidden resources, the Surface Water and Ocean Topography (SWOT) satellite will map the planet.
The satellite will provide a better understanding of the Earth’s water cycle, help better manage water resources, and increase knowledge of how climate change affects lakes, rivers, and reservoirs. The mission, jointly developed by NASA and the French space agency, Center National d’Études Spatiales (CNES), will fill a huge data gap about the planet’s water resources. The satellite will measure the height of the water on the Earth’s surface. It will also be equipped to detect features such as eddies that are less than 100 kilometres wide in the ocean.
NASA said SWOT will also measure more than 95 percent of Earth’s lakes larger than 15 acres and rivers wider than 330 feet in width. Along with measuring the height of the water when in a lake, river, or reservoir, the spacecraft will also measure its width, or area. This important information allows scientists to calculate how much water flows through fresh water. Scientists have long thought that climate change is speeding up the Earth’s water cycle. Warmer temperatures mean the atmosphere can hold more water (in the form of water vapor), which can cause rain storms that are heavier than the area would normally see.
The change could have major implications for global agriculture and food production. “As the Earth’s water cycle intensifies, predicting future extreme events such as floods and droughts requires tracking changes in ocean water supply and demand, as well as land use.” “A global SWOT view of all water on Earth’s surface will allow us to provide precision,” said Nadya Vinogradova Shiffer, SWOT Program Scientist.
The spacecraft will use a Ka-band radar interferometer (KaRIn), which will reflect the radar pulses from the water surface and receive the return signal with two antennas simultaneously. The radar can simultaneously collect information about a distance of almost 120 kilometres from the planet. The SWOT mission is scheduled to launch in November from Vandenberg Space Base in California.
