Sentences with phrase «snowpack declines in»

The unusual nature of recent snowpack declines in the North American Cordillera.

Gregory T. Pederson et al., The unusual nature of recent snowpack declines in the North American Cordillera, Science, vol.

Gregory T. Pederson et al., Regional patterns and proximal causes of the recent snowpack decline in the Rocky Mountains, US, Geophysical Research Letters, vol.

Not exact matches

A new study of long - term snow monitoring sites in the western United States found declines in snowpack at more than 90 percent of those sites — and one - third of the declines were deemed significant.

«Snowpack levels show dramatic decline in western states, U.S..»

Since 1915, the average snowpack in western states has declined by between 15 and 30 percent, the researchers say, and the amount of water lost from that snowpack reduction is comparable in volume to Lake Mead, the West's largest manmade reservoir.

Also an author on the fourth IPCC report, he had led a 2005 study on western snowpack levels that had also documented declines that were less dramatic than those in this new study.

While we have long range climate predictions that show a decline of snowpack by the end of the century and short - range rain and snow forecasts, until now there has been little information on what to expect in the next two months to two years.

This time, no return to cooler period Tim Barnett, a climatologist at Scripps Institution of Oceanography, said the new results appear to agree with his earlier work that used climate models to show humans» greenhouse gas emissions have contributed to declining snowpack in the western United States.

Researchers have evaluated different mechanisms that could account for declining snowpack in a warming world: earlier onset of snowmelt, a change in melt rates and shifts from snow to rain under certain conditions.

«The Northern Rockies have shown the greatest response to warming in terms of snowpack decline,» said lead author Greg Pederson, a research scientist at the U.S. Geological Survey's Northern Rocky Mountain Research Center.

Although the new study describes ongoing decline in snowpack throughout the Rockies, this year has bucked that long - term trend.

Singer suggested a regional decline in snowpacks and less groundwater recharge at the mountain fronts has negatively affected water resources.

Montana's snowpack has declined over the observational record (i.e., since the 1930s) in mountains west and east of the Continental Divide; this decline has been most pronounced since the 1980s.

The average snowpack in the Cascades has declined 50 percent since 1950 and will be cut in half again in 30 years if we don't start addressing the problems of climate change now.

Most studies agree that general declines in snowpack across the West have resulted from warming spring temperatures (Mote 2003; Hamlet et al. 2005; Mote et al. 2005; Abatzoglou 2011; Kapnick and Hall 2012; Pederson et al. 2013a; Lute et al. 2015); however, declines in winter precipitation may also be important (Clow 2010).

For example, Mote and Sharp (2016) showed that western Montana and the Pacific Northwest have experienced the most drastic declines in snowpack volume in the West over the past 80 yr.

In the Rocky Mountains, spring (February - March) warming since the 1980s has been largely responsible for recent snowpack declines at mid - and low - elevation sites (Pederson et al. 2013b).

While this year's snowpack is fairly healthy, in a world warming from increasing greenhouse gases, the early spring snowpack has been declining over the long run.

A new study published in npj Climate and Atmospheric Science (a Nature publication) shows that snowpack levels across the western U.S. have declined over the last 100 years.

The observed melting is greatest at lower elevations, a trend matched in snowpack declines across the Western U.S.

They include soaring temperatures, declining late - season snowpack, northward - shifted winter storm tracks, increasing precipitation intensity, the worst drought since measurements began, steep declines in Colorado River reservoir storage, widespread vegetation mortality, and sharp increases in the frequency of large wildfires.

A new study of long - term snow monitoring sites in the western United States found declines in snowpack at more than 90 percent of those sites - and one - third of the declines were deemed significant.

Snowfall varies across the region, comprising less than 10 % of total precipitation in the south, to more than half in the north, with as much as two inches of water available in the snowpack at the beginning of spring melt in the northern reaches of the river basins.81 When this amount of snowmelt is combined with heavy rainfall, the resulting flooding can be widespread and catastrophic (see «Cedar Rapids: A Tale of Vulnerability and Response»).82 Historical observations indicate declines in the frequency of high magnitude snowfall years over much of the Midwest, 83 but an increase in lake effect snowfall.61 These divergent trends and their inverse relationships with air temperatures make overall projections of regional impacts of the associated snowmelt extremely difficult.

Declining mountain snowpack in western North America.

«If snowpack declines, forests become more stressed, which can lead to ecological changes that include alterations in the distribution and abundance of plant and animal species as well as vulnerability to perturbations like fire and beetle kill.»

If treatments at this scale are completed and repeated over the next several decades, increases in runoff could help offset the current and projected declines in snowpack and stream flow due to warming while improving the resilience of forest stands.

The magnitude of observed declines in snowpack in the Southwest, in the range of 20 %, is similar to the increases in runoff associated with thinning from this study, suggesting that accelerated thinning may at least offset or ameliorate runoff losses due to climate change.

In the western United States, for example, snowpack is declining and snowmelt - driven streamflow is shifting to earlier in the year, leading to greater water stress in summer monthIn the western United States, for example, snowpack is declining and snowmelt - driven streamflow is shifting to earlier in the year, leading to greater water stress in summer monthin the year, leading to greater water stress in summer monthin summer months.

Declines in snowpack are projected to continue as temperatures warm and more winter precipitation falls as rain rather than snow throughout the Pacific Northwest.

Snowpack is projected to decline by as much as 40 percent in the Cascades in the next 30 years, and hotter and drier landscapes will increase the risk of forest fires.

In the coming decades, warmer temperatures, declining snowpack, and changes in soil moisture are expected to lead to a long - term transformation of the state's forest landscapeIn the coming decades, warmer temperatures, declining snowpack, and changes in soil moisture are expected to lead to a long - term transformation of the state's forest landscapein soil moisture are expected to lead to a long - term transformation of the state's forest landscapes.

As temperatures in the Northwest continue to rise this century, scientists expect snowpack to keep declining.2 In the Cascades, scientists project a reduction of as much as 40 percent in the amount of snow on April 1 by the 2040s, under a business - as - usual emissions path.11, in the Northwest continue to rise this century, scientists expect snowpack to keep declining.2 In the Cascades, scientists project a reduction of as much as 40 percent in the amount of snow on April 1 by the 2040s, under a business - as - usual emissions path.11, In the Cascades, scientists project a reduction of as much as 40 percent in the amount of snow on April 1 by the 2040s, under a business - as - usual emissions path.11, in the amount of snow on April 1 by the 2040s, under a business - as - usual emissions path.11, 12

As the climate of the Pacific Northwest warms, more winter precipitation is falling as rain, compared with historical averages.2 With declining snowpack in Oregon's Cascade Mountains, peak stream flows are occurring earlier, and summer flows are declining.2 These changes are expected to continue as heat - trapping emissions grow, putting more stress on already endangered salmon that return to the Columbia and other rivers in the region to spawn.2

In the Cascades, where cool - season temperatures have risen 2.5 ° F (about 1.4 ° C) over the past 40 to 70 years, snowpack has declined by an average of 25 percent — and up to 60 percent in some areas.3, 4In the Cascades, where cool - season temperatures have risen 2.5 ° F (about 1.4 ° C) over the past 40 to 70 years, snowpack has declined by an average of 25 percent — and up to 60 percent in some areas.3, 4in some areas.3, 4,5

Sustainable groundwater management is essential to adapt to this massive loss of water storage and continued decline in snowpack — California is projected to lose up to 80 percent of its historic snowpack by the end of the century as temperatures continue to rise.

In the winter despite a small increase in precipitation, retained snowpack at the end of the winter has declineIn the winter despite a small increase in precipitation, retained snowpack at the end of the winter has declinein precipitation, retained snowpack at the end of the winter has declined.

Sea levels are rising (ask the Mayor of Miami who has spent tax monies to raise road levels), we've had 15 of the hottest years eve measured, more precipitation is coming down in heavy doses (think Houston), we're seeing more floods and drought than ever before (consistent with predictions), the oceans are measuring warmer, lake ice in North America is thawing sooner (where it happens in northern states and Canada), most glaciers are shrinking, early spring snowpacks out west have declined since the 1950's, growing seasons are longer throughout the plains, bird wintering ranges have moved north, leaf and bloom dates recorded by Thoreau in Walden have shifted in that area, insect populations that used to have one egg - larva - adult cycle in the summer now have two, the list goes on and on.

Snowpack is expected to decline in the decades ahead, reducing surface water supplies in locations throughout the western US Photo: US Department of Agriculture Photo: NRCS

«Over the past millennium, late 20th century snowpack reductions are almost unprecedented in magnitude across the northern Rocky Mountains and in their north - south synchrony across the cordillera... the snowpack declines and their synchrony result from unparalleled springtime warming that is due to positive reinforcement of the anthropogenic warming by decadal variability.

The average snowpack in the Cascades has declined 50 percent since 1950 and will be cut in half again in 30 years if we don't start addressing the problems of climate change now.

So it seems quite clear that there is a potential connection, in a statistical sense, between human - caused global warming, declining Arctic sea ice, and the anomalous blocking pattern this winter that has added to other factors we know are tied to human - caused climate change (warmer temperatures and increased soil evaporation, and decreased winter snowpack and freshwater runoff) to produce the unprecedented drought this year in California.

Due to more frequent droughts and declining snowpacks,» [y] ou're going to have an increasingly limited resource and increased demand from cities such as Los Angeles and Las Vegas» for water typically used by Rocky Mountain ranchers, said Rick Ridder, a veteran Democratic consultant in Denver.

The lead author of the new study says a 30 percent decline in mountain snowpack is «very likely» and greater losses are possible.

So if it was just humans acting on the climate system, we're predicting a 30 percent decline in snowpack between now and 2040.

We know now, in a parallel study, that these losses in snowpack — historical and future — are tied to declines in Columbia River streamflow.

The red dots indicate 307 stations that saw a decline in snowpack since 1982, while the blue dots show the 47 that saw an increase.

It not only verifies that the snowpack has declined already in many areas of the West over the past three decades but also concludes that this decline was caused by greenhouse gas emissions.