(NASA)

In case the disappearing animals, towns running dry, sinking land and empty waterways didn't hammer home the severity of California's worst drought on record, NASA produced a series of images that show just how much water the state has lost in the last decade-plus.

Theside-by-side satellite image comparison taken by satellites from NASA's Gravity Recovery and Climate Experiment (GRACE) show total water loss across California over a 12 year period from June 2002 to June 2014. The color palette ranges from green to red, with red values representing the greatest total water loss during the 12 year span.

Deep reds stretch across California's Sacramento and San Joaquin rivers basins, where more than 4 trillion gallons of water is being lost on an annual basis as the drought deepens, NASA notes.

Significant snowfall accumulations in the Sierra Nevada Mountain Range are needed in the coming months if California is to recover from the drought. As weather.com senior meteorologist Jon Erdman reports, 75 percent of all of the West's freshwater comes from snowmelt, not rain.

Peak wet season in California usually runs from November to March, but a ridge of high pressure, known as the "Ridiculously Resilient Ridge" for its exceptional longevity, parked over the Pacific Northwest in January 2013 and cut short the wet season, sucking dry air into California that prevented precipitation and effectively incited the current drought.

Even when the rain finally came in late September, it did little to lessen California's drought. According to the U.S. Drought Monitor, 50 out of California's 58 counties are currently experiencing some degree of exceptional drought, the worst possible measure.

MORE ON WEATHER.COM: Before/After Pictures Show the Severity of California's Drought

The Green Bridge passes over full water levels at a section of Lake Oroville near the Bidwell Marina on July 20, 2011, in Oroville, California. (Paul Hames/California Department of Water Resources/Getty Images)