Letter from the US: California's drought highlights global warming's danger

Global warming is not only exacerbating California's drought, it has likely transformed the ecology of the state well into the f

California has what is called a Mediterranean climate, which means it has two seasons, wet and dry one. The wet one usually starts in November and lasts through the winter and early spring and is characterised by rain, and snow in the northern part of the Sierra Nevada Mountains. In the dry season, from mid-spring through October, there is little or no rain.

In recent years the wet season has become shorter, with less rain and snow, while the dry season has lengthened and grown hotter. This reached the point four years ago when the state was officially declared to be in a drought, which has continued to the present and has become more extreme.

Global warming is not only exacerbating the drought, it has likely transformed the ecology of the state well into the future.

The dry season is marked by wildfires, but these have become worse due to drought. This year has seen twice the usual number of fires, with one especially destructive that virtually wiped out a small town. It spread so fast that seasoned firefighters said they had never seen anything like it.

There is only one year's worth of water left in the state's reservoirs. That groundwater also is in danger Jay Famiglietti, a senior water scientist at the NASA Jet Propulsion Laboratory in California warned last March.

At the end of the last wet season, which was hardly “wet” at all, the snow pack in various parts of the Sierra Nevada, the run-off from which is key to supply water in the summer, was between 16% and 22% of normal levels.

Big business

Agriculture is big business in the state, concentrated in the Central Valley that runs between the Sierra Nevada and Costal mountain ranges. California accounts for more than 60% of total US fruit and nut production and 51% of vegetables.

Agricultural losses due to the drought are worth tens of billions of dollars. Some crops have been abandoned. As growers scramble for the depleting water supply, they have turned to pumping up more groundwater from ever deeper wells. As a result, the surface ground level in the Central Valley has dropped by more than 30 centimetres.

There are many smaller effects of the drought. One example is that black bears have been coming down from the hills into a small town, looking for food, as their regular food supplies are dwindling. This includes the acorns these omnivores rely on. Oak trees in these hills have died or stopped producing acorns.

California Governor Jerry Brown has declared a state of emergency and called for a 25% reduction in water use. The target is aimed at individuals and small businesses, not agribusiness, which sucks up 80% of California water. There have been small cutbacks imposed on this sector by necessity.

Oil

Also let off the hook is Big Oil. California is a major oil producer. The April 8San Francisco Chronicle reports, “A typical Central Valley oil well pulls up nine or 10 barrels of water for every barrel of petroleum that reaches the surface. In addition, companies often flood oil reservoirs with steam to coax out the valley's thick, viscous crude, which is far heavier than petroleum found in most other states. They pump high-pressure water and chemicals underground to crack rocks in the controversial practice of hydraulic fracturing. They use acid and water to clear up debris that would otherwise clog their oil-producing wells.”

All that leftover contaminated water has to go somewhere. According to The Chronicile, state regulators allowed oil companies to fill 170 aquifers that could be suitable for drinking or irrigation with fracking waste. Companies drilled another 253 wells close to aquifers, and the waste can seep into them.

So not only does Big Oil use up a lot of water, it poisons other water sources.

In addition to favouring agribusiness and Big Oil in the emergency, there is a big discrepancy between individuals who are conserving and those who are nt.

As Regina Johnson said in the July 28 Socialist Worker: “We aren't 'all equal' when it comes to access to vital resources, like water — or food or housing, for that matter. Rancho Santa Fe … is a gated community with multi-acre estates, country clubs and ranches. There, water consumption has gone up by 9% since Brown's mandatory 25% reduction went into effect…

“One example from the Bay Area: The historically Black and working-class city of Oakland uses 57 gallons per person per day, compared to Diablo, an elite community a 30-minute drive away, where use is at 345 gallons per person.”

El Nino?

Noah S. Diffenbaugh, associate professor of earth system science at Stanford University, and Christopher B. Field, director of the department of global ecology at the Carnegie Institution for Science, wrote the September 18 New York Times: “As wildfires rage, crops are abandoned, wells run dry and cities work to meet mandatory water cuts, drought-weary Californians are counting on a saviour in the tropical ocean: El Niño.

“This warming of the Pacific occurs about every five years, affecting climate around the globe and bringing heavy winter precipitation to parts of California. The state experienced two of its wettest years during two of the strongest El Niños, in 1982-83 and 1997-98.

“Now climatologists have confirmed that a powerful El Niño is building, and forecasts suggest a high likelihood that El Niño conditions will persist through the next several months. So we in California expect a rainy winter.

“But before everyone gets too excited, it is important to understand this: Two physical realities virtually ensure that California will still face drought, regardless how this El Niño unfolds.

“The first is that California has missed at least a year's worth of precipitation, meaning that it would take an extraordinarily wet rainy season to single-handedly break the drought. Even if that happened, we would most likely suffer from too much water too fast, as occurred in the early 1980s and late 1990s, when El Niño delivered more rainfall than aquifers could absorb and reservoirs could store.

“The second is that California is facing a new climate reality, in which extreme drought is more likely … Our research has shown that global warming has doubled the odds of the warm, dry conditions that are intensifying and prolonging this drought, which now holds records not only for lowest precipitation, but also for the lowest spring snow pack in the Sierra Nevada in at least 500 years. These changing odds make it much more likely that similar conditions will occur again, exacerbating other stresses on agriculture, ecosystems and people.”

The research on the snow pack was based on studies of tree rings in centuries-old blue oaks, which strongly correlate with summer run-off from the Sierra snow pack. The study indicated that present drought conditions are a once-in-1,000 years event. It is difficult to believe that this rare event is a random coincidence with global warming.

Diffenbaugh and Field said: “At the same time, extreme wet periods may also increase because a warming atmosphere can carry a larger load of water vapour. In a possible preview, persistent El Niño conditions this year could force Californians to face both flooding and drought simultaneously. The more rainfall there is, the more water will be lost as runoff or river flow, increasing the risk of flooding and landslides. Add in the fact that the drought and wildfires have hardened the ground.”

This and other studies indicate that while El Niño is likely to increase the snow pack this year, which will ameliorate somewhat the drought next summer, the drought will not end this year. If this projection is correct (and this is the scientific consensus), the drought will continue for more years to come.

To understand the impact of this is on California's economy, it is useful to look at the state's water use structure. The importance of the snow pack in the Sierra Nevada is indicated by the fact that its runoff as it melts fills reservoirs that provide a third of all the drinking water for the state, as well as water to fight fires and generate electricity.

The Central Valley is naturally a desert. It has become fertile only through massive irrigation from water pumped from the rivers that depend on the snow pack. The snow accumulates well north of the Central Valley. Water pumped from the rivers that depend on the snowpack not only irrigates the farms in the Valley, but is an important source for Los Angeles and all of southern California.

The present and future danger resulting from the disruption of this water system is obvious. To carry through the large-scale revamping necessary to cope with this disaster runs directly into the obstacle of the big capitalist firms involved, who are driven by the iron necessity of maximizing their profits, no matter what the costs to society at large.

As is the case with all the problems caused by the burning of fossil fuels, no long-term solutions are available under the capitalist system. Partial reforms can be fought for and won, but such struggles will pit the working people against powerful capitalist interests, which will open the door to understanding that the system itself must be changed.

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