Local rain doesn’t fill our pipes. Of the three main sources that do, Lake Mead, the Colorado River storage reservoir serving Southern California, shrank in July to its lowest level since 1956. Last month, the State Water Resources Control Board concluded that the Sacramento-San Joaquin Delta is overdrawn by 50%.

The scorching temperatures and dry skies threatening Russia's wheat harvests have also been beating down on Western Europe, which is forecasting lower output of crops from French wheat to Italian tomatoes.

Colorado’s iconic aspen trees aren’t going to die off any time soon, says a Forest Service researcher who studied a puzzling and unprecedented decline in aspen health that was first noticed in 2004. Sudden aspen decline ultimately affected about 17 percent of the state’s aspen forests, mostly in the southwestern part of the state. “It was a pretty severe event.

Using statistical methods borrowed from the insurance industry, researchers at Sandia National Laboratories say they’e calculated the potential economic costs of global warming for each of the lower 48 states.

Colorado has experienced several serious droughts since the state was settled in the late 1880s. The most serious droughts came in the 1930s dustbowl era, and again in the 1950s, when another multi-year dry spell hit the state.

Federal climate researchers said this week that a weak start to the monsoon season and a shift from El Niño to La Niña conditions could expand drought conditions across parts of Arizona and New Mexico that are already dry.

Californians need to take significantly less water from the state's single largest supply, according to a state report that could lay the foundation for more limits on water shipments to the Southland.

The world has entered a new geologic epoch, in which human activities will largely determine the planet's evolution, reports the United States' chief scientific body, the National Academy of Sciences.