sierra nevada

California Storms And The Megadrought | Earth Wise

February 22, 2023 By EarthWise Leave a Comment

California experienced its wettest 10-day period in 25 years as a result of a series of storms driven by atmospheric rivers in January. The Rocky Mountains got buried in snow from the same weather pattern. For the drought-stricken West, the storms were good news. But they are not the cure for what’s been ailing the region.

In California, the snowpack in the Sierra Nevada mountains has been greatly enhanced, containing twice as much snow as is considered average for this time of year. Without a doubt, it will reduce the impact of the drought that has plagued the state for 23 years. But one big storm or even a series of them is not enough to undo years of minimal precipitation and rising temperatures. Many of the states’ largest reservoirs remain well below historical averages despite the record-breaking rain. It would take several wet years to really allow the state to recover from the drought.

The snowfall in the Rockies is crucial because it is the source of more than two-thirds of the water in the Colorado River. The Colorado River is the water lifeline for 40 million people from Wyoming to Mexico.

The ongoing shrinking of the Colorado River is a crisis that has created massive problems for the multibillion-dollar agriculture industry and for many large cities, including Denver, Phoenix, Salt Lake City, Las Vegas, and Los Angeles. Two of the nation’s largest reservoirs – Lake Mead and Lake Powell – are filled by the Colorado River. The historic low levels of these reservoirs have threatened the functioning of hydropower facilities that provide electricity to millions of people.

The January storms were good news for the West, but its problems are not over.

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This Winter’s Rain and Snow Won’t be Enough to Pull the West Out of Drought

Photo, posted September 18, 2022, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Trees Are Dying | Earth Wise

August 19, 2022 By EarthWise Leave a Comment

California relies on extensive forests to help reduce the amount of carbon dioxide entering the atmosphere. But extensive drought and increasingly frequent wildfires have been reducing the state’s tree population for the past three decades.

A comprehensive study by a team of scientists from the University of California Irvine used satellite data to study vegetation changes between 1985 and 2021. Across the entire state, tree cover area has declined 6.7% over that time period. The results varied from region to region across the state.

Southern California exhibited the sharpest decline, where 14% of the tree population in local mountain ranges vanished, potentially permanently. In the Sierra Nevada mountains, tree populations were relatively stable until about 2010. After that, a severe drought followed by historically large wildfires resulted in a 8.8% die-off of trees. The northern parts of the state, with higher rainfall and cooler temperatures, fared better, being able to more easily recover from wildfires.

The study goes beyond measuring the tree population of the state and its effects on carbon storage. The data is also important for understanding how changes in forest cover affects water resources and fire behavior in the state.

The decline of trees in California is affecting the carbon storage abilities of the state. The satellite survey showed that as the tree populations have dropped, the state’s coverage of shrubs and grasses has risen, possibly indicating that permanent ecosystem shifts are occurring. The forces contributing to the decline of trees in California are not going away any time soon. As a result, the threat to California’s ability to mitigate the effects of climate change continues to grow.

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UCI study: California’s trees are dying, and might not be coming back

Photo, posted March 24, 2016, courtesy of David Fulmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alaskan Icemageddon | Earth Wise

January 25, 2022 By EarthWise 1 Comment

December saw some wild weather in Alaska. A combination of record high temperatures and torrential rainstorms resulted in the coining of the term “Icemageddon” to describe what was going on with the weather.

Kodiak Island in southern Alaska saw a high temperature of 67 degrees on December 26, which was warmer than it was in Southern California that same day. This set an all-time record for the warmest December day in Alaska. Such a high temperature is amazing considering how little sunlight Alaska gets at this time of year. And with warmer air comes wetter air, as the atmosphere is capable of holding more water vapor as temperatures increase.

As a result, that same day saw the interior of the state get an inch of rain in just a few hours, something that hadn’t happened for decades. But then, when temperatures plummeted again, all that rainwater froze.

Huge sheets of ice blocked roads and choked traffic in Fairbanks, Alaska’s second largest city. Indeed, it was the state’s transportation department that came up with the term icemageddon to describe the situation.

The extreme warmth in December is related to the same weather pattern that brought cold, wintry weather to the Pacific Northwest and Northern California. Those weather conditions resulted in hundreds of cancelled flights in Seattle, where temperatures dropped into the 20s, and in massive amounts of snowfall in the Sierra Nevada mountains in California. A strong area of high pressure anchored in the Northern Pacific resulted in a clockwise flow around it drawing warmer, more tropical air from the Pacific up to Alaska.

Climate change continues to push the envelope on what sort of weather is possible all over the world.

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Alaska faces ‘Icemageddon’ as temperatures swing wildly

Photo, posted April 30, 2015, courtesy of Naql via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildfires And Giant Sequoias

October 28, 2021 By EarthWise Leave a Comment

Two massive California wildfires that erupted during a lightning storm on September 9 have continued to threaten groves of giant sequoia trees in the southern Sierra Nevada mountains. As of the beginning of October, flames from the KNP Complex fire had burned in or passed through 11 sequoia groves, including the famed Giant Forest in Sequoia National Park.

Hundreds of firefighters battled to protect some of the most renowned trees, including the 275-foot-tall General Sherman tree, widely considered to be the largest tree on earth by overall volume. That tree and many near it are over 2,000 years old.

Firefighters wrapped the base of the General Sherman and several other trees with fire-resistant blankets to protect them from the intense heat of approaching fires. Sequoias are actually well-adapted to fires because of their thick bark that protects them from heat. But intense fires like the KNP Complex and Windy fires are more than the trees can handle.

As of the beginning of October, both fires continue to blaze, but thanks to the efforts of firefighters, most of the giant sequoias have survived. One massive tree in the Giant Forest recently toppled over after burning for several days, but most are still standing and haven’t suffered serious damage.

As of early October, the two fires had blackened over 140,000 acres across national parks, national forests, the Tule River Indian Reservation, and local communities. These two are among multiple wildfires burning in California this past summer. The largest – the Dixie fire – has burned nearly a million acres as of early October. In total, over 2.5 million acres have already burned in California this year.

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KNP Complex fire triggers flurry of new evacuations, as flames threaten more giant sequoia trees

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Hundreds of California firefighters battle to protect ancient sequoia groves from raging wildfires – with world’s largest tree General Sherman wrapped in aluminum foil blanket

Photo, posted November 5, 2017, courtesy of Ken Lund via Flickr.

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Recovering Condors | Earth Wise

August 12, 2020 By EarthWise Leave a Comment

The California condor is the largest North American land bird. Its wingspan is nearly 10 feet and its weight of up to 26 pounds nearly equals that of the trumpet swan, the heaviest native North American bird. California condors can live up to 60 years, making them among the world’s longest-living birds as well. But California condors became extinct in the wild in 1987.

Lead poisoning is the primary threat to condors. The birds are scavengers and feeding on the carcasses of dead animals that contain fragments of lead rifle ammunition is responsible for half of all condor deaths.

Condors historically occupied California’s Sierra Nevada mountains and were known to nest in the cavities of giant sequoia trees. By 1982, the wild population was reduced to just 22 birds, and all of those were eventually trapped and brought into captivity to prevent extinction of the species.

A captive breeding program was undertaken at the Los Angeles Zoo and the San Diego Wild Animal Park. With the success of that program, in 1992 the U.S. Fish and Wildlife Service began releasing condors back into the wild in the mountains of Los Padres National Forest in Southern California. That flock has grown to about 100 birds through both wild reproduction and additional release of captive-bred birds.

The Southern California flock continues to expand its range with birds in 8 California counties and even in Arizona, Utah, and Baja California in Mexico. The total wild population of condors is now estimated to be about 340 birds. Recently, condors have been spotted in Sequoia National Park, a part of its historic range where the birds have been absent for nearly 50 years.

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California Condors Spotted in Sequoia National Park, First Time in Nearly Half a Century

Photo, posted May 20, 2005, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Dying California Trees

December 16, 2016 By EarthWise

California’s trees are dying. According to the U.S. Forest Service, more than five years of drought in California has left 102 million dead trees across 7.7 million acres of forest. In fact, 62 million trees have died this year alone – a 100% increase from 2015.