Research geographer Prasad Thenkabail of the U.S. Geological Survey will speak at 7 p.m. Thursday, Aug. 30, at the USGS offices in Menlo Park about the implications for global food and water security in the 21st century on a planet with a population expected to exceed 9 billion by 2050.

Today, 70 percent of the Earth's fresh water goes toward growing food for human consumption, and the need will be greater in 2050, when the world will need another 2.5 billion acres of cropland and the water to irrigate it, according to a USGS statement. Global food security will be "a primary requirement for human advancement, overall societal health, and peaceful coexistence."

The talk takes place in Conference Room A in Building 3 at 345 Middlefield Road in Menlo Park.

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