WaterCalifornia’s agriculture feels pain of harsh drought

The California drought is expected to be worse for the state’s agricultural economy this year because of reduced water availability, according to a new study. Farmers will have 2.7 million acre-feet less surface water than they would in a normal water year — about a 33 percent loss of water supply, on average. Reduced availability of water will cause farmers to fallow roughly 560,000 acres, or 6 to 7 percent of California’s average annual irrigated cropland. The drought is estimated to cause direct costs of $1.8 billion — about 4 percent of California’s $45 billion agricultural economy. When the spillover effect of agriculture on the state’s other economic sectors is calculated, the total cost of this year’s drought on California’s economy is $2.7 billion and the loss of about 18,600 full- and part-time jobs.

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WaterWinners and losers in California’s water crisis

A recent article highlights the widening gap of inequality between the wealthy and the poor of California, specifically in relation to the State’s current drought. The authors discuss what has caused these inequalities to expand — the outdated and unsupervised water regulations still currently used, combined with decentralized local control means using and sourcing water comes down to the simple matter of what people can and cannot afford.

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WaterNew EPA rules extend Clean Water Act protection to more streams, wetlands

Aiming to clarify the ambiguities of the federal Clean Water Act, the Environmental Protection Agency (EPA) last week issued a new ruling which take a tougher approach to the protection of streams and wetlands which support wildlife habitats and filter drinking water supplies. EPA officials have warned that up to 60 percent of the streams and millions of acres of wetlands in the United States are not protected under current law. The new regulations would bring these streams and wetlands under the protection of the Clean Water Act.

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WaterWarming amplifying adverse effects of California’s historic drought

Although record low precipitation has been the main driver of one of the worst droughts in California history, abnormally high temperatures have also played an important role in, according to a recent study by the U.S. Geological Survey and university partners. Experiments with a hydrologic model for the period October 2013-September 2014 showed that if the air temperatures had been cooler, similar to the 1916-2012 average, there would have been an 86 percent chance that the winter snowpack would have been greater, the spring-summer runoff higher, and the spring-summer soil moisture deficits smaller.

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WaterHimalayas glaciers volume to decline dramatically, affecting region’s water supply

Glaciers in High Mountain Asia, a region that includes the Himalayas, contain the largest volume of ice outside the polar regions. If greenhouse-gas emissions continue to rise, glaciers in the Everest region of the Himalayas could experience dramatic change in the decades to come – and may decline by between 70 percent and 99 percent by 2100. Changes in glacier volume can impact the availability of water, with consequences for agriculture and hydropower generation. While increased glacier melt initially increases water flows, ongoing retreat leads to reduced meltwater from the glaciers during the warmer months. “The signal of future glacier change in the region is clear: continued and possibly accelerated mass loss from glaciers is likely given the projected increase in temperatures,” says a researcher.

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Decision making“Echo chambers” fuel climate change debate: Study

A new study demonstrates that the highly contentious debate on climate change is fueled in part by how information flows throughout policy networks. The researchers found that “echo chambers” — social network structures in which individuals with the same viewpoint share information with each other — play a significant role in climate policy communication. The researchers point out that the debate on climate change is not indicative of inconclusive science. Rather, the debate is illustrative of how echo chambers influence information flows in policy networks. “Our research underscores how important it is for people on both sides of the climate debate to be careful about where they get their information. If their sources are limited to those that repeat and amplify a single perspective, they can’t be certain about the reliability or objectivity of their information,” says one of the authors.

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WaterHow climate change is making California’s epic drought worse

By Catherine Gautier

California is undergoing a record-setting drought that began in 2012, the worst in at least 1,200 years. California and other southwestern states have suffered through multi-year droughts in the past, but how does climate change figure into what’s happening now? Can scientists separate the effect of rising greenhouse gas levels on the current drought from other factors? Detecting and attributing observed or projected impacts to man-caused climate change is not an easy task. But there is some supporting evidence from improving numerical climate models and the record of several diverse meteorological and hydrological events already happening, including heat waves, flooding, or droughts. Scientists can run climate model experiments that include only natural variability and then include manmade factors, such as greenhouse gases. These tools serve to highlight and distinguish the dominant mechanisms responsible for particular air circulation characteristics. These climate model simulations show that the extreme and persistent circulation patterns that have caused droughts on the West Coast this century are due to anthropogenic external forces, not natural causes. Studies suggest that climate change might give rise to a new climate regime, one in which the years of low precipitation will be accompanied by warm conditions, creating the aforementioned “warm drought.”

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