Latest survey tallies more than 100 milion dead trees
California’s long-term drought has claimed another 36 million trees, the U.S. Forest Service said this week, announcing the results of a new aerial survey. Since 2010, more than 100 million trees have died across 7.7 million acres, the agency said.
The die-off intensified in 2016, after four years of drought, with mortality increasing 100 percent. Millions of additional trees are weakened and expected to die in the coming months and years. Forest Service leaders once again emphasized that their ability to address safety issues linked with dead trees has been severely hampered by climate change and limited resources.
Draft document highlights global warming threats to state
Colorado Governor John Hickenlooper says a “shifting climate” threatens many of the state’s vital industries, including skiing and agriculture, and he wants the state’s power plants to cut greenhouse gas emissions by 35 percent in the next 15 years from 2012 levels. The goals are outlined in a draft version of an executive order on mitigating and adapting to climate change, which spells out some specific threats of global warming that are already well-known, including:
Greater air pollution will lead to a more hospital admissions and increased cases of respiratory illness;
Changes in precipitation can adversely impact the amount and quality of Colorado’s water resources;
Changes in runoff patterns, intense precipitation, and rising temperatures can negatively affect food production and result in greater risk of food contamination and waterborne illness.
Some climate models project more rainfall in the West
While most recent research suggests that the Colorado River will be depleted well beyond current demands as global temperatures increase, there may be one small bright spot on the horizon. Even if runoff from snow declines, groundwater replenishment in the basin may hold stead under projected increases in precipitation, the U.S. Geological Survey and U.S. Bureau of Reclamation found in a new study.
“You can’t manage what you don’t measure,” said Fred Tillman, lead author and USGS scientist. “These results are the first step in understanding the quantity of groundwater we can expect in the Upper Colorado River Basin; however, further studies are needed to help more accurately forecast future groundwater availability.”
The Colorado River is a critically important source of water for more than 35 million people in the United States and 3 million people in Mexico. As much as half the water flowing in the rivers and streams in the Upper Colorado River Basin originates as groundwater. Understanding how much groundwater is available and how it’s replenished is important to sustainably manage both groundwater and surface water supplies in the Colorado River basin now and in the future.
In the new study, USGS and Reclamation scientists estimated projected changes in groundwater recharge for the Upper Colorado River Basin from recent historical (1950–2015) through future (2016–2099) time periods using climate projections and a groundwater-recharge model.
Simulated future groundwater recharge through 2099 is generally expected to be somewhat greater than the historical average in most decades due to an anticipated wetter future climate in the basin under the most advanced climate modeling projections. Groundwater resources are replenished through increases in precipitation, which may offset reductions from increased temperatures. The full report is available online in the journal Geophysical Research Letters.
But researchers urged caution interpreting the results because a few of the models suggested decreased future recharge relative to the historical climate period.
Deadly heatwaves and flooding part of emerging pattern of extremes
Blistering, record heat in the Southwest helped propel the lower 48 states to a new high-temperature record in June, with an average reading of 71.8 degrees Fahrenheit for the month. That included a new monthly temperature record set in Death Valley National Park, where the average temperature in June was 101.9 degrees Fahrenheit.
The warmest-ever June reading broke the record set during the Dust Bowl era, in 1933, according to NOAA’s National Centers for Environmental Information. The year-to-date is the third-warmest on record, the monthly state of the climate summary report said.
Climate change is wiping out forests on a staggering scale
California’s multiyear drought killed even more trees than previously thought, the U.S. Forest Service announced this week. Aerial and ground surveys show that 26 million trees across six counties in Southern California died, in addition to the 40 million trees that died statewide from 2010 to October 2015. Four years of drought, high temperatures and an outbreak of tree-killing bark beetles all contributed the historic levels of tree die-off, the agency said.
Around the same time, pine beetles started spreading across northern Colorado, parts of Wyoming and North Dakota, ultimately killing millions of acres of forest. And just as the pine beetle infestation waned, a spruce beetle outbreak in southern Colorado started to spread. Since 1996, spruce beetles have killed trees across about 1.5 million acres of forest.
Pacific Ocean ENSO cycle a key player in global climate
By Bob Berwyn
The shift from a powerful El Niño to the cooler La Niña phase of Pacific Ocean temperatures will temporarily end the planet’s recent record streak of record-warm years, according to climate scientists who see the cyclical ocean changes as a key factor in the long-term global climate change equation.
LOWER AUSTRIA — Austria’s high alpine pastures, called Alms, are an important part of the country’s cultural tradition. For centuries, herders have driven cattle and sheep up and down the sides of the mountains following seasonal cycles of plant growth and snow melt.
The livestock grazing is managed mindfully to promote vegetation growth and biodiversity. It may be a difficult concept to grasp at first, but the rhythm of alpine grazing actually fosters biodiversity. Orchids, medicinal herbs and wildflowers thrive in the clearings and create lush green open patches in the landscape that are aesthetically pleasing.
In recent decades, the simple shelter huts near the pastures have also been developed as a recreational and economic resource, providing meals and lodging for tourists and serving as base camps for trekkers and cyclists.
At the Hochbärneck Alm, 900 meters elevation, there are also two ski lifts, but this past winter, they only operated for two days. Just 20 years ago, the ski season ran from late November through March. In recent years, it has barely snowed and temperatures were have been above the 20th century average nearly every day.
But climate change is taking a toll on Austria. The country’s average temperature has increased by 2 degrees Celsius in the past 50 years, more than twice the global average of .85 degrees Celsius, according to a 2014 climate assessment. That warming spells big changes for mountain environments, including the bucolic pastures around the Alm. For now, the cowbells still chime, but the future is uncertain.
A sustained heatwave last summer hit Austrian agriculture especially hard, and the odds of more extreme weather are good, according to many recent climate studies. The heatwave also took a big bite out of Austria’s glaciers, where decades of rapid melting is one of the clearest signs of global warming.
Austria’s government has formally recognized the cultural, economic and ecological values of traditional mountain agriculture as part of its climate policies, and an ambitious national adaptation plan seeks to address the challenges by helping communities boost ecosystem health. Keeping forests, meadows and streams healthy is one of the best ways to protect against climate change impacts.
With support from the Earth Journalism Network and Internews, we’ll be exploring this topic for the next several weeks, following herders as they move their livestock up into the Alpine zone, on through to the end of the summer, when the cows-bedecked with flowers and bells, are driven back to the valley towns for the winter in a colorful procession.
We’ll explore some of the best practices for sustaining ecosystems and mountain communities and ask whether the farmers are getting the support that’s needed, as spelled out by the adaptation plan. And we’ll here from them what changes they’ve already experienced.
Follow our Twitter feed for frequent updates and Instagram for photos from the reporting project — and don’t be afraid to ask questions or add comments about global warming in the Austrian Alps. We’ll include those questions in our interviews with environmental experts, resource managers and government officials as we report on climate change in the Austrian Alps.