Posted on January 2, 2015 by Bob Berwyn
Tornado numbers low for third year in a row.
Scientists say they can’t pinpoint and long-term trends
FRISCO — The number of tornadoes in the U.S. was below average for the third year in a row, NOAA scientists said last week. A preliminary count shows there were about 800 tornadoes in 2014, the lowest number since 1982 and about 20 percent below the long term average. Continue reading
Filed under: climate and weather, extreme weather | Tagged: 2014 tornadoes, climate, extreme weather, tornadoes | 1 Comment »
Posted on December 26, 2014 by Bob Berwyn
Some birds won’t nest at all during drought years.
Some Sonoran Desert species skip breeding entirely during extreme drought
FRISCO — Drought-driven delayed nesting by some southwestern bird species may lead to crashing populations, scientists said in a new study that looked closely at Sonoran Desert bird species, such as Black-tailed Gnatcatchers and Verdins.
The research suggests drought conditions are delaying nesting by two weeks or more for some species. Despite recent rainfall, drought conditions persist in much of the Southwest, making life tough even for species adapted to a dry environment.
Delayed nesting makes the birds more vulnerable to nest predators and parasites, according to the scientists with Point Blue Conservation Science and the U.S. Geological Survey finds that increased drought frequency in southwestern North America results in increased instances of delayed nesting. Continue reading
Filed under: biodiversity, climate and weather, climate change, Environment, global warming | Tagged: Birds, climate change, drought, extreme weather, Southwest | Leave a comment »
Posted on December 18, 2014 by Bob Berwyn
Forest Service scientists study aftermath of Rim Fire to assess effectiveness of forest health treatments
A NASA Earth Observatory image shows smoke plumes from the Rim Fire in August, 2013. NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response.
FRISCO — A detailed new study of fire behavior of the 2013 Rim Fire in Yosemite provides a nuanced view of the effectiveness of forest health treatments.
The Rim Fire was the largest recorded fire in the Sierra Nevada region, and U.S. Forest Service researchers said in their study that the fire burned with moderate to high intensity on days the Rim Fire was dominated by a large pyro-convective plume, a powerful column of smoke, gases, ash, and other debris — regardless of the number of prior fires, topography, or forest conditions. Continue reading
Filed under: climate and weather, Environment, forest fires, Forest health, forests, US Forest Service | Tagged: extreme weather, Forest health, Rim Fire, U.S. Forest Service, Wildfires | Leave a comment »
Posted on December 16, 2014 by Bob Berwyn
Is melting sea ice shifting the jet stream?
Study finds robust link between Arctic ice decline and severe Eurasian winter weather
FRISCO — If you feel like you’ve been on a weather roller coaster, maybe it’s because the jet stream has been behaving like one more and more often in recent years.
Instead of flowing around the mid-latitudes of the northern hemisphere with a few ripples, some years, the high-altitude river of air has been more like a writhing, out-of-control fire hose, snaking and looping, carrying huge surges of warm air north and cold. polar air south. At times, the jet stream has been getting stuck in that pattern for longer stretches. Continue reading
Filed under: Arctic, climate and weather, extreme weather, global warming | Tagged: Eurasian winter, extreme weather, global warming, Jet stream | 1 Comment »
Posted on December 13, 2014 by Bob Berwyn
Last week’s Pacific storm dropped near-record rain
The video was created by NASA/NOAA’s GOES Project at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
FRISCO — A weekend storm rolling into Colorado won’t have a direct pineapple connection, but if the powder does pile up, it will be due to a big stream of moisture from the subtropical Pacific ocean that is wrapped into the approaching weather front.
As the National Oceanic and Atmospheric Administration described in a press release, the ‘Pineapple Express’’ happens when warm air and lots of moisture are transported from the Central Pacific, near Hawaii, to the Eastern Pacific Ocean. The above animation of satellite imagery from NOAA’s GOES-West satellite showed the stream of clouds associated with that moisture from Dec. 9 to Dec. 12, 2014 and brought rain and snow to the western U.S. Continue reading
Filed under: climate and weather, Drought, El Niño, extreme weather | Tagged: California drought, climate, El Nino, extreme weather | 3 Comments »
Posted on December 13, 2014 by Bob Berwyn
Attribution studies still somewhat sketchy
Does global warming cause extreme weather?
FRISCO — A Stanford University climate researcher says that better modeling, advanced statistical analyses and a more robust set of observational climate data will help scientists under stand whether global warming is leading to more extreme weather events like floods, droughts and heat waves.
Such events appear to happening more frequently around the world, but because high-quality weather records go back only about 100 years, most scientists have been reluctant to say if global warming affected particular extreme events. Continue reading
Filed under: climate and weather, extreme weather, global warming | Tagged: climate change, drought, extreme weather, flooding, global warming, Storm surge | 1 Comment »
Posted on December 7, 2014 by Bob Berwyn
Tree rings show the current combination of dryness and heat makes this the worst drought in 1,200 years
Researchers expect drought to become frequent and last longer. MAP COURTESY IPCC.
FRISCO — California’s current drought is already going down as one of the worst in recorded era, and a new tree-ring study by scientists shows it may be the driest period for the region in 1,200 years.
Researchers with the University of Minnesota and Woods Hole Oceanographic Institution collected new tree-ring samples from blue oak trees in southern and central California.
“California’s old blue oaks are as close to nature’s rain gauges as we get,” said University of Minnesota professor Daniel Griffin. “They thrive in some of the driest environments where trees can grow in California.” These trees are particularly sensitive to moisture changes and their tree rings display moisture fluctuations vividly,” Griffin said. Continue reading
Filed under: climate and weather, Drought, extreme weather, global warming | Tagged: California drought, climate change, extreme weather, global warming | 1 Comment »