Scientists Chris Landry adds simulated dust to snow in the mountains of Colorado to study how dust affects snowmelt.
Click on image for full size
Courtesy of the Center for Snow and Avalanche Studies

Desert Dust Alters Ecology of Colorado Alpine Meadows
News story originally written on June 29, 2009

Dust blown into the San Juan Mountains of Colorado is causing snow to melt faster in the springtime. Scientists have found that this is changing how alpine plants that live on the high mountain tundra react to changing seasons, indicating that global warming could have a big impact on plant growth.

The dust is from the desert areas in the southwest United States. Today, five times more dust blows into the mountains than 150 years ago. More human activity in the desert is creating more dust. Also, climate change is causing the desert to get warmer and drier, which will likely cause even more dust to blanket mountain snow in the future.

"It's striking how different the landscape looks as result of this desert-and-mountain interaction," said scientist Chris Landry, who contributed to the study. The snow that remains in the spring is so covered with desert dust that it looks like soil. Dark colored dust reflects less sunlight than white snow. This retains more heat, causing snow to melt faster.

When snow on mountaintops melts slowly through the warmer months of the year, there is a steady supply of water for the ecosystem and for cities, towns, and farms. However, when dust causes snow to melt quickly in the spring, there is less water for the ecosystem and for humans during summer and fall.

To study the impact of dust on snow and tundra plants, the scientists simulated dust effects on snowmelt in areas of the San Juan Mountains. They measured how much dust sped up snowmelt, and how the life cycles of alpine plants were changed.

The timing of snowmelt signals to mountain plants that it's time to start growing and flowering. Early snowmelt caused by dust could change this, which could affect the whole ecosystem. For example, many species of plants could flower at the same time, increasing competition for water and nutrients.

"With increasing dust deposition from drying and warming in the deserts," said scientist Heidi Steltzer, who led the study, "the composition of alpine meadows could change as some species increase in abundance, while others are lost, possibly forever."

Last modified July 7, 2009 by Lisa Gardiner.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Kingdom Plantae

Kingdom Plantae contains almost 300,000 different species of plants. It is not the largest kingdom, but it is a very important one! In the process known as "photosynthesis", plants use the energy of the...more

Tundra Biome

In the very cold places of the world, survival isn't easy. The soil is frozen, its top surface thawing only during summer, and no trees can grow. Yet plants and animals that are adapted for the harsh...more

Global Warming: Scientists Say Earth Is Heating Up

Earth’s climate is warming. During the 20th Century Earth’s average temperature rose 0.6° Celsius (1.1°F). Scientists are finding that the change in temperature has been causing other aspects of our planet...more

The Desert Biome

Deserts are full of interesting questions. How can anything survive in a place with hardly any water? Why is it so dry to begin with? You can find at least one desert on every continent except Europe....more

Biomes and Ecosystems

Biomes are large regions of the world with similar plants, animals, and other living things that are adapted to the climate and other conditions. Explore the links below to learn more about different biomes....more

Triggers of Volcanic Eruptions in Oregon's Mount Hood Investigated

Scientists have learned that Mount Hood, Oregon's tallest mountain, has erupted in the past due to the mixing of two different types of magma. "The data will help give us a better road map to what a future...more

Oldest Earth Mantle Reservoir Discovered

The Earth's mantle is a rocky, solid shell that is between the Earth's crust and the outer core, and makes up about 84 percent of the Earth's volume. The mantle is made up of many distinct portions or...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA