About these ads

Climate: Greenhouse gases drive Australia drying trend

Since the 1970s, southern Australia has been experiencing declining rainfall in the fall and winter, creating scenes like this one in a 2007 photograph at Lake Hume. (Creative Commons/ Suburbanbloke)

Since the 1970s, southern Australia has been experiencing declining rainfall in the fall and winter, creating scenes like this one in a 2007 photograph at Lake Hume. (Creative Commons/ Suburbanbloke).

New model can resolve some climate impacts on a regional scale

STAFF REPORT

FRISCO — Increasing concentrations of greenhouse gases and ozone depletion over Antarctica are the main drivers of the long-term decline in rainfall over southwestern Australia, federal scientists said in a weekend press release.

The findings, published in Nature Geoscience, are derived from a new  high-resolution climate model that may help researchers identify more links between heat-trapping gases and regional climate trends, including here in the U.S. Continue reading

About these ads

Climate: Utah tree-ring study shows severity of historic megadroughts

Luminosity.

Old Douglas firs can help reveal historic climate cycles.

Recent dry spells not so bad compared to past centuries

Staff Report

FRISCO — A tree-ring reconstruction of Utah’s climate going back to 1429 shows that the state has experienced several mega-droughts in past centuries that would be life-changing if they happen again, according to Brigham Young University professor Matthew Bekker.

The worst drought of the modern era, the 1930s Dust Bowl, barely ranks on the top 10 list of droughts in that 500-year span,” Bekker said. The findings reinforce similar studies for the Colorado River Basin. Continue reading

Western wildfires burning bigger and more often

Global warming seen as key factor in trend

wildfire acreage graph

Study documents significant trend in size and frequency of western wildfires.

sdfg

Western wildfires: How much bigger will they get?

By Summit Voice

FRISCO — The size and frequency of western wildfires have been increasing at a startling rate the past few decades, researchers said this week after scrutinizing satellite data to measure burned areas.

The number of wildfires larger than 1,000 acres increased by a rate of seven fires a year from 1984 to 2011 and the total areas burned grew by about 90,000 acres per year — an area the size of Las Vegas, according to the new study accepted for publication in Geophysical Research Letters, a journal published by the American Geophysical Union.

“We looked at the probability that increases of this magnitude could be random, and in each case it was less than one percent,” said Philip Dennison, an associate professor of geography at the University of Utah in Salt Lake City and lead author of the paper. Continue reading

Environment: Is the Amazon rainforest near a tipping point?

A NASA photo taken from the International Space Station shows sunlight glinting off the Amazon River.

A NASA photo taken from the International Space Station shows sunlight glinting off the Amazon River.

Drought the main driver of destructive fires

By Staff Report

FRISCO — Longer droughts, land-use changes and wildfires may  be pushing parts of the Amazon rainforest toward an ecological tipping point, a team of scientists said after analyzing the effects of fire in a series of study plots.

The changes may abruptly increase tree mortality and change vegetation over large areas, the researchers said, pointing out that current Amazon forest models don’t include the impacts of wildfires. As a result, projections of future forest health tend to underestimate the amount of tree death and overestimate overall forest health, said Dr. Michael Coe, of the Woods Hole Research Center. Continue reading

Climate: Warmer temps to drive spread of drought

State officials hope to be well-prepared for the next inevitable drought in Colorado.

Drought is expected to expand the southwestern U.S. and other regions.

Evaporation seen as huge factor in climate calculations

Staff Report

FRISCO — Increasing global temperatures will drive drought expansion regardless of precipitation in some cases, as more moisture evaporates from soils.

An increase in evaporative drying means that even regions expected to get more rain, including important wheat, corn and rice belts in the western United States and southeastern China, will be at risk of drought. The study excludes Antarctica.

The new study models the effects of both changing rainfall and evaporation rates on future drought, estimating that 12 percent of land will be subject to drought by 2100 through rainfall changes alone; but the drying will spread to 30 percent of land if higher evaporation rates from the added energy and humidity in the atmosphere is considered.

Continue reading

Western streamflow forecasts a mixed bag

Severe drought continues in Southwest

kj

California, Arizona and New Mexico reporting very dry conditions.

By Summit VoiceFRISCO — Snowpack across the West is still somewhat of mixed bag in this no-Niño winter, but February storms did help bolster water supplies across the northern tier of states, according to the monthly update from USDA’s Natural Resources Conservation Service.

East of the Continental Divide as well as parts of Washington, northern Oregon, northern Idaho and western Montana are now forecast to have near-normal or above normal water supplies, according to the forecast from the NRCS National Water and Climate Center. Continue reading

Climate: How hot will it get in Colorado?

State releases draft climate change report, comments wanted

dg

How warm will it get in Colorado?

By Summit Voice

FRISCO — Climate experts say it’s about to get warmer —probably much warmer — in Colorado. A draft state climate report released this week for public comment shows that Colorado has warmed by 2.5 degrees Fahrenheit in the past 50 years. By the middle of this century, summer temperatures will be higher than in all but the hottest years, with another 2.5 to 5.5 degrees of warming expected. Continue reading

Climate: USGS says most California streams flowing at less than 10 percent of normal

Widespread western drought continues

jk

Much of the West has been very dry during the first four months of the 2014 water year.

By Summit Voice

As California experiences its worst drought in more than a century, it’s probably not surprising that some stream gages in the northern part of the state are showing all-time record low readings, with 2013 in the record books as the driest calendar year in the state’s 119-year recorded history.

Low streamflow affects water availability for agricultural, municipal, and industrial uses, water quality, water temperature, recreational opportunities, and the maintenance of fish populations.

Recent precipitation has resulted in some increases in streamflow, snowpack, and reservoir levels, but severe drought conditions remain. Without significant additional precipitation, prior conditions will quickly return leaving most streams in the state at less than 10 percent of normal for this time of year. Continue reading

California drought linked with global warming

‘What we are seeing now is fundamentally different from previous mega-droughts, which were driven largely by precipitation’

hg

Global warming is likely to exacerbate droughts worldwide.

By Summit Voice

FRISCO — While drought conditions have eased across parts of the U.S. in recent months, conditions have worsened in the far West, and particularly in California, where water shortages will have consequences spreading far beyond the state’s borders.

And the western drought has global warming fingerprints all over, according to four researchers who discussed the links between climate change and drought at a teleconference organized by Climate Nexus, a communications group focused on highlighting the wide-ranging impacts of climate change. Continue reading

Climate: U.S. temps cooler than average in 2013

kh

Cooler than average temperatures were widespread across the U.S. in December 2013.

California drought intensifies

By Summit Voice

FRISCO — December 2013 won’t go down in the record books for cold temperatures even though cooler-than-average readings prevailed across much of the country.

The average temperature across the lower 48 states was 2 degrees Fahrenheit below the 20th century average, making it the coldest December since 2009, according to the monthly summary released this week by NOAA’s National Climatic Data Center. Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,259 other followers