Mastering Environmental Science Case Study Tour Transcript
Withgott Case Study Tour: Chapter 15 Transcript
Welcome to your Case Study Video Tour. In this tour, we’ll explore the science behind the recent drought in California, its impacts, and efforts being made throughout the state to adapt to a drier climate. Let’s get started!
California's drought has been ongoing for quite a while.
Record-low levels of precipitation coupled with record-high heat have kept California in drought conditions since 2012 and made water scarcity one of the greatest challenges faced by the state in recent memory.
In 2015, Governor Jerry Brown stood on the shore of Lake Tahoe and stated, “This is the new normal,” referring to his state’s current drought, “and we’ll have to deal with it.” Ironically, scientists have postulated that “normal” for California is actually quite dry.
The drought has largely been driven by the lack of intense “atmospheric river” precipitation events, which can supply up to 50% of the state’s annual precipitation. In these events, moist air from the Pacific rushes inland over the California coast.
Since 2011, a high-pressure system in the eastern Pacific has interfered with the atmospheric river events. Normally this air makes it to the Sierra Nevada Mountains. It usually results in precipitation and snow. This snowpack melts to supply water to rivers.
Lack of precipitation and low river water levels due to the noted deficiency in snowpack has impacted the state’s agricultural industry. Agriculture from California normally utilizes 80% of its water, and this water helps grow half of the produce in the United States.
Reservoirs that supply cities with water are draining, threatening the water supply for millions of people. Water levels in some reservoirs have fallen drastically. Low water levels in California reservoirs have also reduced hydroelectric power generation by 60% since 2012.
Organisms other than human beings have been impacted by the drought as well. Animals as well as plants have been dying off. Giant kangaroo rats living in the Carrizo Plain, north of Los Angeles, are starving as their habitat is slowly turning into a desert.
Chinook salmon are experiencing massive die-offs in northern California as water levels drop and temperatures rise to lethal levels. Populations of smelt are also at critical levels, and their scarcity is depriving other fish and predatory birds of an important food source.
Data from the state’s water utilities indicated that in May 2015, one month after the state-wide restrictions were mandated, residential water use across the state dropped by 29% compared with May 2013, with some regions averaging reductions of more than 38%.
Much work remains to be done in California to develop sustainable, long-term water conservation programs. But one of the most important hurdles that has already been overcome is convincing Californians that saving water is important to the future of their state and is a movement worth embracing.