national park

A lake in Death Valley

March 14, 2024 By EarthWise Leave a Comment

Death Valley in California is the driest place in North America, averaging only 2 inches of rain each year. Badwater Basin in Death Valley is the lowest point in North America with a depth of 282 feet below sea level. Currently, Badwater Basin is the site of an ephemeral lake called Lake Manley.

The lake formed again last August after Hurricane Hilary drenched the California desert. Water levels in the lake dropped throughout the fall, but it never quite dried up. But then the relentless rains of early February filled the lake once again.

Water that gathers in Badwater Basin usually evaporates faster than it can be replenished, leaving the lakebed dry. But between the hurricane and the February storm, nearly 4 inches of rain have fallen, and the lake has stayed alive. There is a river that feeds the lake – the Amargosa – that is really flowing in the aftermath of the storms.

The lake is nearly 7 miles long and 4 miles wide, but the water is only about a foot deep. This is not the first time it has formed but it is an unusual occurrence. It formed in 2005, but only lasted about a week. Death Valley National Park officials expected that the lake would be gone by October, but it persisted into the new year which then brought the atmospheric river-driven California rainstorms.

At this point, it is unclear how long the lake in the driest place in America will be around. While it is there, visitors to the national park can enjoy beautiful views of the nearby mountains reflected in its waters.

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Deep in Death Valley, a Sprawling Lake Takes Form

Photo, posted February 19, 2024, courtesy of Tom Hilton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Too Many Bison | Earth Wise

September 21, 2023 By EarthWise Leave a Comment

In the northern part of Yellowstone National Park, an historically large bison herd is hampering the comeback of quaking aspen trees, whose numbers were greatly diminished by decades of over-browsing by elk. Restoring the balance of ecosystems at Yellowstone is proving to be a complicated matter.

Long ago, the bison population in the Great Plains was as much as 30 million. The population sharply decreased in the 1800s. By the 1830s, there were no bison east of the Mississippi River. Fifty years later, the Plains bison was nearly extinct. Several small herds lived near Yellowstone Park when it was established in 1872, but poachers killed off nearly of them by the turn of the century. Protective measures were taken and by 1925, Yellowstone’s Lamar Valley herd had grown to more than 750. After that, occasional culling took place for over 40 years.

When gray wolves and cougars were removed from the park, elk populations boomed, and the elk gradually decimated the growth of quaking aspen, cottonwood, willow, and berry-producing shrubs. Both elk and bison were regularly culled until 1968 when public and congressional outcry intervened.

The return of wolves and cougars to the park made some progress in restoring ecosystem balance, particularly with respect to the elk population which has dropped from 20,000 to 5,000. But bison numbers have grown to over 4,000 over past 20 years and the damage once caused by elk is now continuing from bison.

Park administrators are faced with complex management decisions about how to best preserve the ecosystems at Yellowstone National Park.

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Bison in northern Yellowstone proving to be too much of a good thing

Photo, posted October 6, 2016, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving Giant Sequoias | Earth Wise

October 13, 2022 By EarthWise Leave a Comment

Last year, the KNP Complex Fire burning in Sequoia National Park drew global attention as the General Sherman, the world’s largest tree, was wrapped in tinfoil-like material in order to repel the flames from the fire. Hundreds of firefighters labored for weeks trying to save giant redwood trees. Despite these efforts, the U.S. Forest Service estimates that wildfires killed 13% to 19% of the world’s giant sequoias in 2020 and 2021.

This past July, the Washburn Fire burned through part of Yosemite’s Mariposa Grove and the giant sequoias there were surrounded by automated sprinklers trying to shelter them from the flames.

For a century, government agencies have worked to extinguish all natural wildfires and prohibited Native people in the region from lighting the fires they traditionally used to manage their lands. As a result, forests have grown far thicker with trees that can fuel fires. The Sierras are now home to more than three times as many trees as when they were managed by indigenous communities. But more than 100 million of those trees had died by 2016 because of drought.

Add to this massive amount of kindling the effects of climate change – a hotter and drier environment – and there is the perfect storm for megafires among the giant sequoias.

There is federal legislation pending that would provide resources for prescribed burning and other forms of active forest management. It is controversial. It has attracted support from the Nature Conservancy, the Save The Redwoods League, and others, but also opposition from more than 80 environmental groups.

What is not controversial is that the Giant Sequoias are in the midst of a crisis and urgent action is needed.

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In California, a Race to Save the World’s Largest Trees From Megafires

Photo, posted December 10, 2014, courtesy of Laura Camp via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Death Valley Flooding | Earth Wise

September 13, 2022 By EarthWise Leave a Comment

Furnace Creek in Death Valley is the driest place in North America. Its average annual rainfall is under two inches. On August 5th, a thousand-year rainfall event dropped 1.46 inches of rain – about three-quarters of a year’s precipitation. The all-time record for a single day is 1.47 inches, set in April 1988. The storm did break the record for the most rain ever recorded in August, which averages just over a tenth of an inch of rain for the entire month.

The flash flood washed debris over roads, swept away and buried cars, knocked a water facility offline, damaged buildings, and stranded about a thousand visitors and staff in Death Valley National Park. By the next day, the flood water had mostly receded, and stranded visitors could be escorted out of the park by National Park personnel.

Death Valley sits at 282 feet below sea level. If it were not for the extremely arid climate there, Death Valley would likely be filled with water. However, humid air masses traveling east from the Pacific Ocean have to cross four mountain ranges before they reach the desert valley. Those air masses lose their moisture in the form of rain on the western slopes of the mountain, leaving a dry area, or rain shadow, on the eastern sides. By the time the air masses reach Death Valley, they are bone dry. On rare occasions, the lowest spot in the valley fills with water forming a wide, shallow lake, known as Lake Badwater.

The extreme heat and aridity of Death Valley evaporates the temporary lake quickly, returning the valley to its usual state. Furnace Creek still holds the record for the highest air temperature ever recorded: 134 degrees Fahrenheit.

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Death Valley Flash Flooding

Photo, posted April 7, 2021, courtesy of Matthew Dillon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Your Children’s Yellowstone

January 25, 2019 By EarthWise Leave a Comment

Yellowstone National Park was the first national park in the US and according to some sources, the first in the world. It is the home of charismatic megafauna and stunning geysers that attract over four million visitors a year. It is the only place in the United States where bison and wolves can be seen in great numbers. And it is changing.

Over the next few decades of climate change, Yellowstone will quite likely see increased fire, less forest, expanding grasslands, shallower, warmer waterways, and more invasive plants. All these things will alter how and how many animals move through the landscape. Ecosystems are always changing, but climate change is transforming habitats so quickly that many plants and animals may not be able to make the transition at all.

Since 1948, the average annual temperature in the Greater Yellowstone ecosystem has gone up by 2 degrees Fahrenheit. On balance, winter is 10 days shorter and less cold. The Northern Rockies snowpack has fallen to its lowest level in eight centuries. Summers in the park are warmer, drier, and increasingly prone to fire.

Non-nutritious invasive plants like cheatgrass and desert madwort have replaced nutritious native plants. When plants like these take over, they suck moisture out of the ground early so that bison and elk cannot be sustained throughout the summer.

The behavior of elk and other animals is already changing, with many staying outside the park to nibble lawns and alfalfa fields. In turn, wolves go where the elk go. Forests and waterways are changing as well.

The rapid changes going on at Yellowstone mean that the park that our children and grandchildren will visit in the future is likely to be a very different one from the Yellowstone we remember.

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In Yellowstone National Park, warming has brought rapid changes.

Photo, posted September 7, 2016, courtesy of Mike Yang via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.