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Images: Storms, Floods, and Droughts

Evaporation from the ocean sends moisture into the atmosphere and leaves behind salt. These maps show areas of the ocean where evaporation (top) and precipitation (bottom) are highest (red) and lowest (blue). The mid-latitude are dry, like oceanic deserts; the tropics and high latitudes are wet, like oceanic rain forests. Measuring the ocean's salinity is a way to measure its evaporation, which starts the cycle that transports water from the ocean into the atmosphere and eventually via rain or snow on to land. Indications are that the Earth's water cycle is intensifying, causing wet areas to become wetter and dry areas to become dryer. (Schanze, Schmitt, and Yu, Journal of Marine Research, 2010)

Warming global temperatures means more evaporation over the ocean, where 86% of the planet's evaporation occurs, and an intensification of the water cycle that creates precipitation, said WHOI oceanographer Ray Schmitt. “As we increase our understanding of oceanic conditions, we are going to do a better job of predicting changes in the water cycle.” (Photo by Tom Kleindinst, Woods Hole Oceanographic Institution)

Ocean conditions, combined with unwise land use by farmers, resulted in the drought that caused the Dust Bowl in the 1930s, which devastated the nation’s agricultural heartland and displaced a million or more people. Scientists warn that chances for similar catastrophes are increasing. (Courtesy NOAA Photo Library)

In the fall of 2012, Ray Schmitt led a NASA-sponsored expedition aboard the WHOI research vessel Knorr to the North Atlantic's saltiest spot to get a detailed picture of how variations in the upper ocean's salinity are related to shifts in rainfall patterns around the planet. Black dashed lines show the approximate cruise track. White "X" marks the location of major experiments. Orange indicates areas of highest salinity. (NASA Jet Propulsion Laboratory)

Salinity measurements collected by instruments in the ocean will be correlated with measurments taken by  Aquarius, NASA's new salinity-sensing satellite launched in 2011. Aquarius offers continuous measurements of ocean salinity patterns over larger areas. Over its three-year mission, Aquarius will collect as many sea surface salinity measurements as the entire 125-year historical record from ships and buoys. (NASA Jet Propulsion Laboratory)

This map show average sea surface salinity measurements in September 2012 collected from the Aquarius satellite. Orange/yellow areas are more salty; blue/purple areas are less salty. Aquarius aims to provide the first global observations of sea surface salinity, covering Earth's surface once every 7 days and achieving accuracy equivalent to 0.2 psu, or about a "pinch" (1/8th of a teaspoon) of salt in 1 gallon of water. (Maps produced by Norman Kuring, NASA Goddard.)

On the deck of R/V Knorr, WHOI physical oceanographer Dave Fratantoni inspected one of several wave gliders, which were deployed during the SPURS expedition. The vehicles use wave motion to propel themselves through the ocean and solar-charged batteries to power their sensors, which will measure temperature, salinity, and meteorological conditions. Other instruments used on the expedition included autonomous gliders, sensor-laden buoys and floats, unmanned underwater vehicles, and expendable bathythermographs. (Photo by Tom Kleindinst, Woods Hole Oceanographic Institution)

Data from tree rings and other indicators of past climate can give water resource managers a record s of a region's drought and flood conditions than spans centuries. “With that knowledge, planners can design strategies realistically based on history, not based simply on the recent climate," said WHOI dendrochronologist Kevin Anchukaitis. (Courtesy of Kevin Anchukaitis, Woods Hole Oceanographic Institution)