A massive winter storm system that whipped up tornadoes, ice and snow from the Gulf of Mexico to the Great Lakes and killed at least three people on Christmas was moving slowly eastward Wednesday.

Hundreds of flights were canceled and people were warned to stay home rather than brave the strong winds, freezing temperatures and treacherous roads.

Volunteers who patrol California beaches for plastic, cigarette butts and other litter will be on the lookout this winter for debris from last year's monstrous tsunami off Japan's coast.

The March 2011 disaster washed about 5 million tons of debris into the sea. Most sank, leaving an estimated 1 1/2 million tons afloat. No one knows how much debris — strewn across an area three times the size of the United States — is still adrift.

A bitter cold spell in Russia has claimed 123 lives in the past 10 days, an official said Tuesday, with the unseasonably early freeze testing authorities in a country used to notoriously tough winters.

Temperatures have plunged to up to minus 30 degrees Celsius (minus 34 degrees Farenheit) in the Moscow region and up to minus 60 degrees Celsius (minus 51 degrees Farenheit) in Eastern Siberia.

Forecasts of snow, sleet and freezing rain threatened to complicate Christmas Day travel around the nation's midsection Tuesday as several Gulf Coast states braced for a chance of twisters and powerful thunderstorms.

A blizzard watch was posted for parts of Indiana and western Kentucky for storms expected to develop Tuesday amid predictions of up to 4 to 7 inches of snow in coming hours. Much of Oklahoma and Arkansas braced under a winter storm warning of an early mix of rain and sleet later turning to snow.

From deadly cold in Russia, floods in Britain and balmy conditions that have residents in southwest France rummaging for their bathing suits, the weather has gone haywire across Europe in the days leading up to Christmas.

The mercury in Moscow has fallen to minus 25 degrees Celsius (minus 13 degrees Fahrenheit) -- unseasonably cold in a country where such chills don't normally arrive until January or February.

A survey of endangered porpoises in China's longest river has yielded fewer sightings as intense ship traffic threatens their existence, scientists said Monday.

Chinese researchers spent 44 days tracking the finless porpoise -- or "river pig" in Chinese -- along a little over half of the 6,000-kilometer (3,700-mile) Yangtze River.

Southwestern areas of the United States, reeling from its worst drought in 50 years, may have 10 percent less surface water within a decade due to global warming, a study said Sunday.

While rainfall is forecast to increase over northern California in winter and the Colorado River feeding area, warmer temperatures will outstrip these gains by speeding up evaporation, leaving the soil and rivers drier, a research paper said.

The West Antarctic Ice Sheet, whose melt may be responsible for 10 percent of the sea-level rise caused by climate change, is warming twice as quickly as previously thought, a study said Sunday.

A re-analysis of temperature records from 1958 to 2010 revealed an increase of 2.4 degrees Celsius (36.3 degrees Fahrenheit) over the period -- three times the average global rise.

Italy's red racing giant Ferrari wants to go green, cutting emissions without sacrificing horsepower and working on a new hybrid model set to thrill pro-environment speed junkies.

"We're working on reducing energy consumption without forgetting that the symbol of Ferrari is performance," Matteo Lanzavecchia, head of development, told AFP at the luxury car-maker's historic factory in Maranello, a small town in the Emilia Romagna region.

Two types of ice seals joined polar bears on Friday on the list of species threatened by the loss of sea ice, which scientists say reached record low levels this year due to climate warming.

Ringed seals, the main prey of polar bears, and bearded seals in the Arctic Ocean will be listed as threatened under the Endangered Species Act, the National Oceanic and Atmospheric Administration announced.