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The federal government has proposed steps to address low water levels on the Colorado River. Last summer, the Bureau of Reclamation said usage would need to be cut by as much as 30 percent after the two large reservoirs on the river—Lakes Powell and Mead—dropped to historic lows. However, the seven states in the basin have yet to reach an agreement.
Lake Powell Utah, (May 2007) | Credit: PRA
Last week, the Bureau of Reclamation announced two alternative plans to cut allocations. One would result in prioritizing the older legal rights of farmers in California and the other would sacrifice those rights to the needs of cities, particularly in Arizona.
Favoring urban needs in Arizona would hurt farmers in Southern California who produce much of the nation’s fruits and vegetables. On the other hand, honoring those historic rights in California could result in Arizona having to curtail much of its Colorado River allocation. According to the New York Times, Arizona’s major canal, the Central Arizona Project, which delivers Colorado River water to Phoenix, Tucson, and farmers in the state, could be reduced drastically.
U.S. Representative Greg Stanton, a Democrat from Phoenix, said that Arizona’s economy would take a beating if California’s senior rights prevail. But J.B. Hamby, a member of the board of the Imperial Irrigation District in Southern California told the Arizona Republic that making cuts entirely by a percentage cut across the board rather than legal rights would unduly harm his state and his district's farmers. He said he does not expect it to come to that as the states continue to find a consensus.
A third proposal is to do nothing, which could result in water levels falling so low that Lake Powell and Lake Mead couldn’t generate hydropower—something the Bureau of Reclamation would probably not allow.
The Arizona Republic reports that negotiations among the states are said to be making progress and there’s growing confidence a deal could be reached that respects older legal rights and doesn’t cut off cities or those with junior allocations.
The federal government’s plans, which don’t currently affect the Upper Basin States of Colorado, Wyoming, Utah, and New Mexico, are now subject to public comment. A decision could come this summer.
Last week, Fort Lauderdale, Florida, suffered a rainstorm that dropped 25 inches of water in seven hours, breaking the previous daily record by more than ten inches. Government data show heavy rainfalls have increased by nearly 30 percent in the Southeast over the past 50 years.
The LOCA2 data estimate how often a “once-in-a-century” day of rain or snow will hit in different climate change scenarios between now and 2100. Colors on the maps show how frequently researchers expect such an extreme precipitation event to occur, with the darkest brown indicating every 30 to 40 years. | Credit: Dave Pierce/Scripps Institution of Oceanography
Climate activist Bill McKibben noted that while the Fort Lauderdale event was a freak of nature, it was also utterly predictable. As the planet warms, the atmosphere can hold more water. He warns that we are entering a phase of steep rises in global temperatures, as El Niño conditions return in the Pacific Ocean.
New research from the Lawrence Berkeley National Laboratory shows that by the end of the century, the biggest rain and snow days will be 20 to 30 percent wetter than they are today. The study reaffirms what climate scientists have been predicting and says that much of the increased precipitation will occur in winter.
But while a warmer atmosphere can hold more water, it can also cause more evaporation. A study led by the Nanjing University of Information Science and Technology in China shows that climate change is making droughts, which occur mostly in the summer growing season, faster and more furious.
So-called “flash droughts,” which they say are particularly nasty and sudden, may lead to a large crop-killing footprint not only from lack of rain or snow but also from global warming, because the atmosphere gets so hot and dry that it sucks water right out of plants and soil. In 2016, a sudden drought occurred in the Southeast, and Jason Otkin, of the University of Wisconsin and a co-author of the study, told the Associated Press it was a factor of the devastating wildfires in Gatlinburg, Tennessee.
The researchers found that flash droughts are occurring more often in nearly three-quarters of the world and are coming on faster.
The precipitation study was published in the Journal of Hydrometeorology.
The flash drought study was published in the journal Science.
From swimming pools to lush landscapes, the lavish lifestyles of the wealthy require a lot of water—and according to a new study, they do so at the expense of the poor. New research led by Uppsala University found high water use by the elite to irrigate gardens, wash cars, or fill pools are driving urban water crises around the globe—at least as much as climate change or population growth.
The locations of some of the direst urban water crises over the past two decades, as reported from several media | Figure created with Matlab R2022b
For their study, the team focused on Cape Town, South Africa, where many poor people live without taps or toilets and use their limited water for drinking and hygiene. The researchers found that affluent households, which make up less than 14 percent of Cape Town’s population, used more than 51 percent of the water consumed in the city, while lower-income groups, which account for nearly two-thirds of the city’s residents, consumed just over 27 percent. The authors say that low-income households are significantly more vulnerable to drought and water crises than the elite, who can afford price increases and find alternative water sources, such as digging wells.
The study said that more than 80 cities worldwide face similar water scarcity and equity issues, including London, Miami, Beijing, Istanbul, Cairo, Moscow, Bangalore, and Mexico City. They add that while solutions to urban water use have focused on raising prices and finding more supplies, more consideration should be given to reducing unsustainable consumption among elites.
The study was published in the journal Nature Sustainability.
Phytoplankton—microscopic ocean organisms—are climate superstars for the amount of carbon dioxide they sequester from the atmosphere through photosynthesis. To grow, all that phytoplankton need is sunlight, CO2, and a few nutrients in the water including nitrogen, phosphorus, and iron. Most iron in the ocean drifts from dust on land, but not much ends up in the Southern Ocean, so any amount of the element found there needs to be recycled.
Iron recycling in the Southern Ocean | Credit: Oleg Belyaev/Institute of Marine Sciences of Andalusia (ICMAN)
That task has been largely handled by a circular relationship between krill—tiny shrimp-like crustaceans—and baleen whales. Krill eat plankton and then are eaten by whales. When whales poop, the iron in their feces is taken up by plankton and the cycle continues. But these two aren’t the only players in this game. New research shows that shorebirds play a key role in iron recycling and in particular, penguins, which punch above their weight.
Scientists led by the Institute of Marine Sciences of Andalusia (ICMAN) in Spain used drone images to estimate the size of Chinstrap penguin (Pygoscelis antarcticus) colonies in Antarctica and then calculated that their poop, also known as guano, contains very high concentrations of iron (about three milligrams per gram). The penguins also feast on krill and have been found to poop an impressive 521 tons of iron back into the icy water each year.
That might sound like a lot, but it’s only half the amount from four decades ago, as the birds’ numbers have plummeted due to climate change. Less penguin guano affects phytoplankton growth, which in turn will sequester less carbon and be less able to keep the climate in check. That means Chinstrap penguins—already suffering from global warming—will take it on the chin despite doing their utmost to keep ecosystems healthy.
The research was published in the journal Nature Communications.