A long-term cycle of too little water from melting snow and rain to counter the effects of evaporation has caused water levels in Lakes Michigan and Huron to fall to record low levels. There's too little data to say the problem is a product of global warming, but it's a cycle that's been seen before.

The SWOT mission will provide a comprehensive view of Earth's freshwater bodies and allow scientists to accurately monitor lake levels globally. Hydrologists will use the data from SWOT to help water managers better prepare for water related hazards such as drought and floods.

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