Thanks to the worst drought in eight decades in southeastern Brazil, water levels have dropped dramatically in the reservoirs that supply São Paulo, the country's largest city. New satellite imagery from NASA reveals that critical reservoirs there have dwindled to 3 to 5 percent of storage capacity, creating shortages in the region.

 

Rainfall totals in the region this year are 12 to 16 inches (300 to 400 millimeters) below normal.

 

According to a poll conducted this week, 60 percent of respondents in São Paulo reported that their water supplies have been restricted at least once in the past 30 days. Three-quarters of those people said the cut lasted at least six hours.

 

The Landsat 8 images show Jaguari Reservoir, one of five lakes in the Cantareira System that supply water to roughly half of the 20 million people in the São Paulo metropolitan area. (Another 20 million live in São Paulo state.) The images show the reservoir in August 2013, before the recent drought began, and again in August 2014.

 

Marcos Heil Costa, a climate scientist at the Universidade Federal de Viçosa, told NASA that the drought has been "unprecedented."

 

Lack of water has hurt coffee farmers and other growers in the area and may hamper economic growth, state officials warn. On Tuesday, a top government official told city dwellers that they may be headed for more severe shortages.

 

Some scientists have suggested that the recent uptick in deforestation in Brazil may be partly responsible for the drought, since loss of evapotranspiration from trees is known to reduce cloud formation.

 

 

PHOTO: NASA satellite images show Jaguari Reservoir in August 2013, before the drought, and in August 2014.

PHOTO COMPARISON, BY NASA EARTH OBSERVATORY