In parched California, rainfall patterns are essentially the same as they were 120 years ago, but humans have made it warmer and that added heat is driving the state’s crippling drought, according to a new study. Warm temperatures dry out soils and cause precipitation to fall as rain rather than snow, thus reducing annual snowpack essential for irrigation, for example. What snow does fall then melts earlier in the spring.
Heat waves, droughts, and downpours across the United States are likely to increase according to a White House report released Tuesday — and experts say all we might be able to do now is prepare for what’s to come.
“People have this perception of this being an issue that affects our kids but not us, or affects polar bears in the Arctic but not us, and what this report really brings home is the fact that climate change is affecting us right here, today,” said Katharine Hayhoe, a lead author of National Climate Assessment report.
The report lays out how dramatic changes in weather, from rising heat to too much water on the East Coast and too little water on the West, will likely impact the U.S. in coming decades.
Wind-whipped mayhem may ratchet up as the global climate adjusts to ever increasing concentrations of greenhouse gases in the atmosphere, according to a new study.
In particular, easterly winds associated with weather systems known as African easterly waves that bring rains critical to crops and livestock in the Sahel, transport Saharan dust within Africa and across the Atlantic Ocean, and play a role in the formation of tropical cyclones –- i.e. hurricanes –- will strengthen.
Ready for a ’90s El Niño flashback?
Researchers are keeping a close eye on a giant pool of abnormally warm water in the Pacific Ocean that some think could trigger another El Niño of epic proportions if it rises to the surface, sending weather patterns into a tizzy around the world.
That could mean heavy rains in drought-stricken California, dry weather across the Midwest and East Coast, and parched landscapes in Australia and South Africa while it pours in South America. The phenomenon is linked to the periodic warming of surface waters in the eastern tropical Pacific Ocean.
During February 1998, a powerful jet stream pounded California with an unrelenting series of wet Pacific storms. Longstanding rainfall records fell. Oceanfront homes slumped into the roiling surf. Roads washed out across the state. Federal disaster areas were declared in 35 counties. At least 17 people died. The Red Cross opened 79 shelters and fed more than 100,000 people.
The culprit? An extreme El Niño, a phenomenon triggered by a warming of waters in the equatorial Pacific Ocean that shifts weather patterns around the world.
El Niño’s ills weren’t confined to California: In 1997-98, torrential rains washed away villages in northern Peru, heat waves rolled across Australia, and massive peat-bog fires cloaked Indonesia in a thick haze. All told, the impacts caused upwards of $45 billion in global economic losses and claimed an estimated 23,000 lives.
If global warming gases build up so much that record-setting rains, droughts and coastal floods routinely bankrupt businesses and cities, the world’s economic and political powers may decide to aggressively re-engineer the global climate. One option is to fill the atmosphere with enough sunlight-reflecting particles to restore surface temperatures to pre-industrial levels. If they do, would all be cool?
Absolutely not, according to a new study that asked the question to 12 models forced to simulate the global climate with four times more carbon dioxide in the atmosphere than existed in 1850, the start of the industrial revolution. Under such conditions, reflecting sunlight in order to lower temperatures to pre-industrial levels would cause monsoonal rains to drop 5 to 7 percent below pre-industrial levels.
As the Earth continues to warm during this century, atmospheric conditions ripe for severe thunderstorms and tornadoes will increase in the U.S., according to a new study.
Given the amount of damage caused by the straight-line winds, golf-ball-sized hail or flash floods associated with any given severe thunderstorm, understanding whether they will increase in frequency or intensity on a warming planet is a key question in climate science.