Climate Change

 

Water keeps White Sands National Park's dunes in place, but when conditions are dry the wind can carry the gypsum sand away.

NASA Photo

 

The White Sands dunefield is a sensitive ecosystem that relies on moisture to keep the dunes in place. If you dig just below the dune surface you will find wet sediment, and if you dig at the base of the dunes you will find groundwater only feet below.

Continued increases in temperature are expected under ongoing climate change. This may have a range of impacts on the dunes, including higher evaporation; lower water table under the dunes; hotter temperatures within the dunes; reduction of the soil moisture that stabilizes the dunes; and possibly reduced flooding events that trigger gypsum growth. As the dunes dry, the gypsum sand is increasingly able to move with the wind, and large-scale drying events have dramatic impacts on dunes and on visitor access to the dunes. The image above is was taken from space during a dry and windy period in 2008 when migrating dunes closed off the dune drive (the road that allows access into the heart of the dunes) in several locations for nearly two weeks. Understanding the relationship between drying conditions and sediment erosion is essential to protect the dunes at White Sands National Park and the amazing plants and animals that are found nowhere else on earth.

To understand and plan for the future, ongoing research in the park is exploring the relationship between climate and the dunes:

• Since 2009, White Sands National Park has been conducting an intense groundwater study in cooperation with the University of New Mexico and New Mexico Tech University, the United States Geologic Survey, and Shoemaker and Associates. This study has demonstrated that the groundwater that keeps the dunes in place is connected to the regional groundwater table.

• Dr. Ryan Ewing from Texas A&M University is studying dune formation and movement using LiDAR and weather stations in the park. This study has provided key insights into the initiation of new dunes as dome dunes (or protodunes), how regional wind regimes result in complex dune shapes, and the speed of dune migration in the system.

• Dr. Kathy Benison is leading a team of researchers from West Virginia University exploring the sedimentology of the modern lake system. This study has demonstrated that gypsum is still forming in the system and providing an ongoing source of sediment.

• Biologists from Princeton, New Mexico State University, the University of New Mexico, and the National Park Service are studying the biology of the park, including adaptation to environmental change and habitat range.

The information provided from these studies and ongoing inventory and monitoring of the dune system will allow park resource managers to make informed decisions which will help protect the dunes and dune ecosystem for years to come.