Posted on March 28, 2015 by Bob Berwyn
Is there a ‘safe’ limit for global warming?
‘No safe limit’
FRISCO — While the world haltingly stumbles down a path aimed at limiting global warming to 2 degrees Celsius, some experts say that target isn’t enough to protect at-risk ecosystems and the world’s most vulnerable populations.
In a commentary for the open access journal Climate Change Responses, Penn State geographer Petra Tschakert said the goal is “utterly inadequate,” leaving millions of people vulnerable to devastating flooding, heatwaves and other impacts they are ill-equipped to deal with. Continue reading
Filed under: climate and weather, Environment, extreme weather, global warming | Tagged: climate change, COP climate talks, Environment, global warming, IPCC | Leave a comment »
Posted on March 27, 2015 by Bob Berwyn
Findings from Swiss-American team present nuanced view of how climate change affects weather extremes
One of this past winter’s northeastern snowstorms swirls off the coast of New England in the satellite image via NASA Earth Observatory.
FRISCO — Adding more fuel to the debate over climate change and extreme weather, Swiss and American scientists this week said their new study shows that global warming tends to reduce temperature variability.
The cold and snowy weather that gripped much of the eastern U.S. this winter was probably not linked to Arctic amplification and increased waviness of the jet stream, according to the scientists with ETH Zurich and the California Institute of Technology.
Changes in the north-south difference in temperatures play a greater role in modifying temperature variability than changes in the jet stream, the researchers said. Continue reading
Filed under: climate and weather, extreme weather, global warming | Tagged: climate change, extreme weather, global warming, Jet stream | 2 Comments »
Posted on March 24, 2015 by Bob Berwyn
Real science, from real scientists.
Expert speakers available in all 50 states
FRISCO — Debates about global warming can quickly descend into murky territory, especially if they take place in a political context. But communities looking for straightforward and nonpartisan scientific information can find from a science speakers network that includes climate experts from all 50 states.
The Climate Voices Initiative was launched last year by the University Corporation for Atmospheric Research and the United Nations Foundation, aiming to bring together scientists with members of local communities to discuss climate science and regional effects of climate change. Continue reading
Filed under: climate and weather, extreme weather, global warming | Tagged: climate adaptation, climate science, Environment, global warming | 1 Comment »
Posted on March 17, 2015 by Bob Berwyn
Finding a signal amidst the climate noise isn’t easy
Does La Niña increase the odds of tornadoes?
Study finds links between ENSO and tornado frequency in the Southern U.S. Photo courtesy NOAA.
FRISCO — Teasing out a link between large-scale atmospheric patterns and specific weather events isn’t easy against the backdrop of natural variability.
But a new study of the El Niño-La Niña cycle in the Pacific Ocean suggests that La Niña — the cool phase of the cycle — increases the frequency of tornadoes and hail storms in some of the most susceptible regions of the United States.
During La Niña, both vertical wind shear and surface warmth and moisture increase significantly in the southern states, making conditions favorable to severe storm occurrence.
The study, published in the current issue of the journal Nature Geoscience, may help provide more information for medium- and long-range extreme weather forecasts. Continue reading
Filed under: climate and weather, extreme weather, global warming | Tagged: climate, El Nino, ENSO, extreme weather, La Niña, tornadoes | Leave a comment »
Posted on March 14, 2015 by Bob Berwyn
‘The risk of high-impact heat waves is likely to increase’
Monsoonal summer thunderstorms help regulate heatwaves. bberwyn photo.
FRISCO — Summer heatwaves, already getting longer and hotter because of human-caused global warming, are set to get even worse, as the overall climate-warming trend disrupts atmospheric circulations that bring relief from long spells of hot weather.
A recent study by scientists with the Potsdam Institute for Climate Impact Research one measurement of accumulated summer storm energy has already declined by 10 percent since 1979. The researchers linked the findings to changes in the Arctic caused by man-made global warming. Continue reading
Filed under: Arctic, climate and weather, extreme weather, global warming | Tagged: Arctic sea ice, extreme weather, global warming, heatwaves | 1 Comment »
Posted on March 12, 2015 by Bob Berwyn
A NASA visualization of Hurricane Floyd approaching the Florida coast in 1999. Hurricane Floyd formed from a tropical wave moving off the coast of Africa to become one of the largest and strongest Atlantic Hurricanes on record.
Spatial cloud coverage offers clues to tropical storm formation
FRISCO — Closely monitoring thunderstorms over Africa may help meteorologists develop better forecasts for Atlantic hurricane development.
“Eighty-five percent of the most intense hurricanes affecting the U.S. and Canada start off as disturbances in the atmosphere over Western Africa,” said Tel Aviv University Prof. Colin Price, who recently published a new study on hurricane formation in Geophysical Research Letters. “We found that the larger the area covered by the disturbances, the higher the chance they would develop into hurricanes only one to two weeks later.”
Working with graduate student Naama Reicher of the Department of Geosciences at TAU’s Faculty of Exact Science, Price analyzed satellite images of cloud cover to track the variability in cloud cover blocking the earth’s surface in West Africa during hurricane season.Using infrared cloud-top temperature data gathered from satellites, Prof. Price assessed the temperatures of the cloud tops, which grow colder the higher they rise. He then compared his cloud data with hurricane statistics — intensity, date of generation, location, and maximum winds — from the same period using the National Hurricane Center data base. Continue reading
Filed under: climate and weather, extreme weather, tropical storms and hurricanes | Tagged: Atlantic hurricanes, Cape Verde hurricanes, climate, extreme weather, hurricane forecasting, hurricane formation, tropical storms | Leave a comment »
Posted on March 4, 2015 by Bob Berwyn
California’s withering drought continues.
Study shows how global warming may very well lead to semi-permanent drought by mid-century
FRISCO — California’s crippling drought may be the new norm, according to scientists who studied the link between greenhouse gases, rising temperatures and multi-year period of record warmth and dryness.
The new study by Stanford researchers found that the worst droughts in California have historically occurred when conditions were both dry and warm, and that global warming is increasing the probability that dry and warm years will coincide.
The findings suggest that California could be entering an era when nearly every year that has low precipitation also has temperatures similar to or higher than 2013-2014, when the statewide average annual temperature was the warmest on record. The study was published in the March 2 issue of the journal of the Proceedings of the National Academy of Sciences. Continue reading
Filed under: climate and weather, Drought, extreme weather, global warming | Tagged: California drought, climate change, global warming, greenhouse gases | 1 Comment »