Study finds liquid water flowing above and below frozen Alaskan sand dunes, hints of a wetter Mars

Mar 29, 2013
Study finds liquid water flowing above and below frozen Alaskan sand dunes, hints of a wetter Mars
Nogahabara Sand Dunes. Credit: U.S. Fish and Wildlife Service

(Phys.org) —The presence of liquid water at and beneath frozen Alaskan sand dunes during Arctic winter suggests that liquid water could also be temporarily stable (or metastable) at frost-covered sand dunes on Mars.

A team of earth and planetary scientists from Southwest Research Institute (SwRI) performed field studies of the Great Kobuk Sand Dunes, which serve as an Earth-based cold-climate "analog" to dunes on the Red Planet. The team conducted fieldwork in Kobuk Valley National Park, Alaska, when the average daily surface temperature was -14.7 degrees C (5.5 degrees F). gathered by SwRI scientists strongly suggest there is a perched layer of liquid water in the dunes occurring just below the seasonally frozen active layer.

While conducting this planetary analog study, the scientists also noticed that several melt-water debris flows had formed on sunward-facing dune slopes. At one location, ground surface temperature measured nearby was within 1 degree C of the thaw point for fewer than 10 minutes. During an even colder period at another dune location, ground measured near active debris flows never approached the thaw point. The scientists surmise that patches of dark sand on bright white snow enabled highly localized thawing.

"Debris flows with gully or erosion tracks also appear on the slopes of several dune fields on Mars. Very few minutes of above-freezing temperatures are needed to locally melt water and mobilize sand transport down steep slopes," said hydrogeologist Dr. Cynthia Dinwiddie, a senior program manager in SwRI's Geosciences and Engineering Division.

These phenomena occur at temperatures corresponding to those observed on the surface of Mars, Dinwiddie said.

"Recent measurements of air temperature and pressure recorded by the Laboratory on the Curiosity Rover, which landed in Gale Crater last August, suggest that liquid water potentially would be stable there during the warmest portion of each day," said Dinwiddie.

, solid ice and water vapor can coexist in stable equilibrium at what is called the triple point of water. Late-winter to early-spring environmental conditions at the Great Kobuk are sufficiently similar to conditions on that these Alaskan dunes can serve as an informative planetary analog, Dinwiddie said.

Explore further: Viruses take down massive algal blooms, with big implications for climate

Related Stories

Winds drive dune movement on Mars

Nov 16, 2011

Sand dunes, a common feature on the surface of Mars, can provide a record of recent and past changes. Some dunes near Mars’ polar areas have been observed to move recently due to carbon dioxide ice sublimation, ...

Are gas-formed gullies the norm on Mars?

Dec 06, 2011

In June 2000, Martian imaging scientists made a striking discovery — data from NASA’s Mars Global Surveyor spacecraft found gullies on the red planet. Gullies on Earth form when water runs down steep ...

Clouds get in the way on Mars

Mar 23, 2012

The science team from the HiRISE camera on the Mars Reconnaissance Orbiter wanted to take another look at a region of icy sand dunes on Mars to look for seasonal changes as spring is now arriving on the Red ...

Study links fresh Mars gullies to carbon dioxide

Oct 29, 2010

(PhysOrg.com) -- A growing bounty of images from NASA's Mars Reconnaissance Orbiter reveals that the timing of new activity in one type of the enigmatic gullies on Mars implicates carbon-dioxide frost, rather ...

Recommended for you

Severe drought is causing the western US to rise

53 minutes ago

The severe drought gripping the western United States in recent years is changing the landscape well beyond localized effects of water restrictions and browning lawns. Scientists at Scripps Institution of ...

A NASA satellite double-take at Hurricane Lowell

1 hour ago

Lowell is now a large hurricane in the Eastern Pacific and NASA's Aqua and Terra satellites double-teamed it to provide infrared and radar data to scientists. Lowell strengthened into a hurricane during the ...

Arctic sea ice influenced force of the Gulf Stream

3 hours ago

The force of the Gulf Stream was significantly influenced by the sea ice situation in the Fram Strait in the past 30,000 years. Scientists at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine ...

User comments : 0