TY - JOUR
T1 - Seasonal erosion and restoration of Mars' northern polar dunes
AU - Hansen, C. J.
AU - Bourke, M.
AU - Bridges, N. T.
AU - Byrne, S.
AU - Colon, C.
AU - Diniega, S.
AU - Dundas, C.
AU - Herkenhoff, K.
AU - McEwen, A.
AU - Mellon, M.
AU - Portyankina, G.
AU - Thomas, N.
PY - 2011/2/4
Y1 - 2011/2/4
N2 - Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.
AB - Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.
UR - http://www.scopus.com/inward/record.url?scp=79551637255&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79551637255&partnerID=8YFLogxK
U2 - 10.1126/science.1197636
DO - 10.1126/science.1197636
M3 - Article
C2 - 21292976
AN - SCOPUS:79551637255
SN - 0036-8075
VL - 331
SP - 575
EP - 578
JO - Science
JF - Science
IS - 6017
ER -