California Central Valley

Data from the GRACE satellites allow scientists to see how fresh water is being redistributed across the continents over time.


CAPITAL: Sacramento

AREA: 18,000 square miles (47,000 km2)


POPULATION: 6.5 million

GEOGRAPHY: The Central Valley is a lowland region that extends through central California from the Cascade Mountains in the north to the Tehachapi Mountains in the south. Its 450-mile-long stretch is bounded by the Pacific Coast Range to the west and the Sierra Nevadas to the east. Ranging in width from 30 to 60 miles (78 to 155 kilometers), the Central Valley is divided into two smaller valleys: the Sacramento Valley in the north and San Joaquin Valley in the south. Major cities in this region of the state include Fresno, Modesto, Stockton and the state’s capital, Sacramento. The Central Valley’s fertile soil and extended growing season make it one of the major agricultural regions in the United States.

CLIMATE: The Central Valley has a hot Mediterranean climate in the north; the southerly parts of the region are dry and categorized as desert. The Central Valley is prone to greater daily and seasonal temperature ranges than the surrounding mountains or the coast. Precipitation in the Central Valley ranges from more than 20 inches (51 centimeters) a year in the north to roughly 5 inches (13 centimeters) a year in the far south.

ECONOMY: Agriculture is the primary industry in much of the Central Valley, with its irrigated valleys accounting for a large share of the fruits and vegetables consumed in the United States. Lettuce, grapes and lemons are among the major crops grown in this region.

Photo © BrendelSignature


The GRACE data visualization shows changes in total freshwater storage across the landscape for the period January 2007 to March 2009, relative to the average amount of water at that location during this period. The blue colors show regions that are wetter than the average and the red colors show regions that are dryer.


Examine areas in detail: