Climate change

Coastal urban centers around the world are urgently looking for new, sustainable water sources as their local supplies become less reliable. In the U.S., the issue is especially pressing in California, which is coping with a record-setting, multidecadal drought. California Gov. Gavin Newsom recently released a US$8 billion plan for coping with a shrinking water supply. Along with water conservation, storage and recycling, it includes desalination of more seawater. Ocean desalination, which turns salt water into fresh, clean water, has an intuitive appeal as a water supply strategy for coastal cities. The raw supply of salt water is virtually unlimited and reliable. Ocean desalination is already a major water source in Israel and the United Arab Emirates. Cities in the Middle East, Australia, Mediterranean Europe, the U.S. Southwest and Australia also rely on it. There are more than 20 ocean desalination plants operating in California, plus a few in Florida. Many more plants acr...

The U.S. Senate voted to ratify an international treaty on Sept. 21, 2022, agreeing to phase out a class of climate-warming chemicals that are widely used as coolants in refrigerators, air conditioners and heat pumps. If you’re getting a sense of déjà vu, don’t be surprised. These chemicals, called hydrofluorocarbons, or HFCs, were commercialized in the 1990s as a replacement for earlier refrigerants that were based on chlorofluorocarbons, or CFCs. CFCs were destroying the ozone layer high in the Earth’s atmosphere, which is essential for protecting life from the Sun’s harmful ultraviolet radiation. HFCs are less harmful than CFCs, but they create another problem – they have a strong heat-trapping effect that is contributing to global warming. If HFCs can be phased down globally – as many countries have agreed to do under the 2016 Kigali Amendment to the Montreal Protocol, the treaty just ratified by the U.S. Senate on a bipartisan...

The summer of 2022 started with a historic flood in Montana, brought on by heavy rain and melting snow, that tore up roads and caused large areas of Yellowstone National Park to be evacuated. It ended with a record-breaking heat wave in California and much of the West that pushed the power grid to the breaking point, causing blackouts, followed by a tropical storm that set rainfall records in southern California. A typhoon flooded coastal Alaska, and a hurricane hit Puerto Rico with more than 30 inches of rain. In between, wildfires raged through California, Arizona and New Mexico on the background of a megadrought in Southwestern U.S. that has been more severe than anything the region has experienced in at least 1,200 years. Near Albuquerque, New Mexico, a five-mile stretch of the Rio Grande ran dry for the first time in 40 years. Persistent heat waves lingered over many parts of the country, setting temperature records. At the same time, during a period of five weeks between...

Hundreds of industrial facilities with toxic pollutants are in Hurricane Milton’s path as it heads toward Florida, less than two weeks after Hurricane Helene flooded communities across the Southeast. Milton, expected to make landfall as a major hurricane late on Oct. 9, is bearing down on boat and spa factories along Florida’s west-central coast, along with the rubber, plastics and fiberglass manufacturers that supply them. Many of these facilities use tens of thousands of registered contaminants each year, including toluene, styrene and other chemicals known to have adverse effects on the central nervous system with prolonged exposure. Farther inland, hundreds more manufacturers that use and house hazardous chemicals onsite lie along the Interstate 4 and Interstate 75 corridors and their feeder roads. And many are in the path of the storm’s intense winds and heavy rainfall. Black dots indicate facilities in EPA’s...

Atmospheric rivers – those long, narrow bands of water vapor in the sky that bring heavy rain and storms to the U.S. West Coast and many other regions – are shifting toward higher latitudes, and that’s changing weather patterns around the world. The shift is worsening droughts in some regions, intensifying flooding in others, and putting water resources that many communities rely on at risk. When atmospheric rivers reach far northward into the Arctic, they can also melt sea ice, affecting the global climate. In a new study published in Science Advances, University of California, Santa Barbara, climate scientist Qinghua Ding and I show that atmospheric rivers have shifted about 6 to 10 degrees toward the two poles over the past four decades. Atmospheric rivers on the move Atmospheric rivers aren’t just a U.S West Coast thing. They form in many parts of the world and provide over half of the mean annual runoff in these regions, including the U.S. Southeas...