2 Heldmann, Jennifer Lynne 2003 An investigation of recent water in the cold climates of Earth and Mars Boulder University of Colorado 180 aquifers, arctic environment, Arctic region, Canada, erosion, erosion features, exobiology, ground water, gullies, hydrology, laser ranging, Mars, Mars Global Surveyor Program, numerical models, permafrost, remote sensing, spectra, springs, temperature, t