Weather

weather

Mighty Mekong cut by monsoon, not tectonics

The rivers draining the Tibetan Plateau are some of the largest, longest and most deeply incised waterways in the world. For decades, most geologists assumed that these river canyons were cut as the plateau was uplifted following the initial collision of the Indian subcontinent with Asia. However, recent studies have found that the plateau was already elevated by 40 million years ago — roughly 20 million years before the deep canyons formed. 

06 Feb 2019

Benchmarks: January 12, 1888: "Schoolchildren's Blizzard" Strikes the Great Plains

By mid-January 1888, the Great Plains had seen ice storms, frigid temperatures and above-average snowfall. On the morning of Jan. 12, however, the weather was unseasonably warm and sunny, with temperatures reaching well above freezing in places. Many people, including children on their way to school, left home without winter coats, hats or mittens. In a matter of hours, everything changed.

12 Jan 2019

Arctic warming causes Siberian cooling

The Arctic is warming faster than anywhere else on Earth, and fall sea-ice extents have been trending downward for decades. But while the region is heating up, that northerly warming seems to be having the opposite effect on some midlatitude locations: Parts of Siberia near the Ural Mountains, for example, have had anomalously cold winters in recent decades.

04 Jan 2019

Winter precipitation in southwestern U.S. tied to Kiwi Coast

Water supplies in the southwestern United States largely depend on winter precipitation. Predicting seasonal rain and snowfall is becoming more difficult, however, as climate change causes precipitation patterns to vary. A new study provides evidence of a strong correlation between late-summer to fall sea-surface temperatures off the coast of New Zealand and winter precipitation in the southwestern U.S. — a correlation that could help provide earlier and more reliable forecasts for the southwestern U.S., and improve water resource and ecosystem management in the region.

21 Nov 2018

Saharan dust a storm killer

Each year between 900 million and 4 billion metric tons of dust from the Sahara Desert in Africa is swept into the atmosphere and blown around the world. In places like Texas, the dust often leads to poor air quality. A new study suggests that desert dust may also suppress the formation of severe storms and hurricanes in the southern United States.

06 Nov 2018

Rivers in the sky: Improving predictions of atmospheric rivers to reduce risk

Researchers are working to improve forecasts of atmospheric rivers — long, narrow systems of moist, tropical air that can deposit enormous amounts of water, bringing both relief from drought and catastrophic flooding.
23 Aug 2018

Comment: The changing shape of local climates

Climate is changing globally, but how will it be experienced locally? Researchers are developing the techniques needed to understand and predict the local consequences of global change.

02 Jul 2018

"Dam levels critical" in Cape Town

At first glance, a visitor to Cape Town might not notice the extent of the parched conditions — people still go about their business, amid the same kind of hustle and bustle you would find in other major cities. But looking closer, there are signs that something is not right. People standing in buckets to conserve water during showers is one such sign, and bottled water flying off grocery store shelves is another.

13 Jun 2018

Cape Town faces a waterless future

The city of Cape Town, South Africa, is bone dry. In 2017, after two straight years of drought, a third drought year offered more of the same.. This past January, city leaders announced that they would shut off the taps to the municipal water supply in April because that was when “Day Zero” — the day when the water supply would run dry — was predicted to occur. Day Zero has since been pushed back to sometime in 2019, but, for 4 million Capetonians, living under the specter of a day without water is the new normal, and signs of that reality litter the city. Sometimes literally.

22 May 2018

El Nino "flavors" affect California rainfall

Twenty years ago, the 1997–98 El Niño surpassed the 1982–83 event to become the strongest El Niño ever recorded, contributing to famine and drought in Southeast Asia, devastating floods in Southern California, and other natural disasters. By many metrics, the 2015–16 El Niño bested both to claim the title of the strongest El Niño on record. This most recent event, nicknamed the “Godzilla El Niño,” did contribute to extreme weather in parts of the world, including disastrous fires in Indonesia and the longest, global coral-bleaching event on record. However, it did not have the anticipated effect on California, which, at the time, was in the midst of a severe multi-year drought. In a recent study, researchers suggest the 2015–16 El Niño was the wrong “flavor” to bring heavy precipitation to the state.

13 May 2018

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