A U.S.-French satellite has been launched  a mission to map all the world's oceans, lakes, reservoirs, rivers and other waterways. The satellite has been dubbed SWOT - Surface Water and Ocean Topography. It went  space just before dawn  Friday. Scientists hope data  the satellite will help them to monitor how climate change is adversely changing water levels. The U.S. broadcaster PBS said: "The satellite is needed more than ever, as climate change worsens droughts, flooding and coastal erosion." A NASA spokesperson spoke  the mission's importance. She said: "It's a pivotal moment....We're going to see Earth's water  we've never seen it before."
The SWOT satellite is  the size of an SUV (sports utility vehicle). It took 20 years to develop,  a cost of $1.2 billion. High-precision radar equipment will measure the height of water  more than 90 per cent of Earth's surface. It will survey millions  lakes, as well as 2.1 million kilometres of rivers. Scientists will identify potential areas  water loss that could threaten local populations and coastlines. NASA said SWOT is a marked technological upgrade  its predecessors. A spokesperson said: "SWOT will give us a ten-fold improvement  the [accuracy] and spatial resolution  our measurements  water height." It will help scientists to better understand, "the critical role the oceans play  climate change".