Polar Ice in the Solar System

Recommended Reading List for Polar Ice in the Inner Solar System

Compiled by: Shane Byrne Lunar and Planetary Laboratory, University of Arizona.

April 23rd, 2007

Polar Ice on Airless Bodies...... 2 Initial theories and modeling results for these ice deposits: ...... 2 Observational evidence (or lack of) for polar ice on airless bodies:...... 3 Martian Polar Ice...... 4 Good (although dated) introductory material ...... 4 Polar Layered Deposits:...... 5 Ice-flow (or lack thereof) and internal structure in the polar layered deposits...... 5 North polar basal-unit ...... 6 Geologic Mapping and impact cratering...... 6 Connection of polar layered deposits (PLD) to climate...... 7 Formation of troughs, scarps and chasmata...... 7 Surface Properties of the PLD ...... 8 Eolian Processes and circumpolar dunes ...... 8 Residual Ice Caps:...... 10 Geomorphology, composition and changes within the Southern Residual Ice Cap..... 10 Geomorphology and composition of the Northern Residual Ice Cap...... 11 Seasonal Ice Caps: ...... 12

Omissions A reading list for terrestrial polar ice deposits and processes is totally beyond the scope of a document like this, so I have only included papers discussing terrestrial ice when there is a useful analogy to some extra-terrestrial example.

Outer solar system satellites are often primarily composed of various ices and display their own menagerie of surface processes and morphologies. A complete treatment of these bodies requires a separate reading list.

Polar Ice on Airless Bodies Icy deposits have been hypothesized to exist in permanently shadowed craters in the polar regions of the Moon and Mercury for some time e.g. Watson et al. [1961]. A planet’s atmosphere can usually transport heat into areas where the sun never reaches; however, on an airless body this process is absent. In permanently shadowed areas, such as within polar impact craters, ice may collect and remain stable over the age of the solar system. Strong evidence for Mercury’s polar ice deposits has been acquired; however, evidence for substantial amounts of polar ice on the Moon remains weak. Despite this, there is currently considerable interest in any possible lunar ice due to its potential to be explored by a manned mission.

Initial theories and modeling results for these ice deposits: Arnold, J. R. (1979), Ice in the lunar polar regions, J. Geophys. Res., 84(B10), 5659– 5667. Butler, B. J. (1997), The migration of volatiles on the surfaces of Mercuryand the Moon, J. Geophys. Res., 102(E8), 19,283– 19,291. Cocks, F., P. Klenk, S. Watkins, W. Simmons, J. Cocks, E. Cocks, and J. Sussingham (2002), Lunar ice: Adsorbed water on subsurface polar dust, Icarus, 160, 386–397. Moses, J. I., K. Rawlins, K. Zahnle, and L. Dones (1999), External sources of water for Mercury’s putative ice deposits, Icarus, 137, 197–221, doi:10.1006/icar.1998.6036. Lanzerotti, L., W. L. Brown, and R. E. Johnson (1981), Ice in the polar regions of the moon, J. Geophys. Res., 86, 3949–3950. Lawrence, D. J., W. C. Feldman, R. C. Elphic, J. J. Hagerty, S. Maurice, G. W. McKinney, and T. H. Prettyman (2006), Improved modeling of Lunar Prospector neutron spectrometer data: Implications for hydrogen deposits at the lunar poles, J. Geophys. Res., 111, E08001, doi:10.1029/2005JE002637. Salvail, J. R. and F. P. Fanale (1994), Near-surface ice on Mercury and the Moon: A topographic thermal model, Icarus, 111, 441-455. Schorghofer, N. and G. J. Taylor (2007), Subsurface migration of H2O at lunar cold traps, J. Geophys. Res., 112, 2010 Vasavada, A. R., D. A. Paige, and S. E. Wood (1999), Near-surface temperatures on Mercury and the Moon and the stability of polar ice deposits, Icarus, 141, 179-193. Watson, K., B. Murray, and H. Brown (1961), On the Possible Presence of Ice on the Moon, J. Geophys. Res., 66, 1598 Watson, K., B. C. Murray, and H. Brown (1961), The behavior of volatiles on the lunar surface, J. Geophys. Res., 66, 3033-3045. Watson, K., B. C. Murray, and H. Brown (1962), The stability of volatiles in the solar system, Icarus, 1, 317-327. Zuber, M. T. and D. E. Smith (1997), Topography of the lunar south polar region: Implications for the size and location of permanently shaded areas, Geophys. Res. Lett., 24, 2183

Observational evidence (or lack of) for polar ice on airless bodies: Bussey, D. B. J., P. G. Lucey, D. Steutel, M. S. Robinson, P. D. Spudis, and K. D. Edwards (2003), Permanent shadow in simple craters near the lunar poles, Geophys. Res. Lett., 30, 11-1. Butler, B. J., D. O. Muhleman, and M. A. Slade (1993), Mercury: Full-disk radar images and the detection and stability of ice at the North Pole, J. Geophys. Res., 98(E8), 15,003– 15,024. Campbell, B. A., D. B. Campbell, A. A. H. J. F. Chandler, M. C. Nolan, and P. J. Perillat (2003), Radar imaging of the lunar poles, Nature, 426,137–138. Campbell, D. B., B. A. Campbell, L. M. Carter, J.-L. Margot, and N. J. S. Stacy (2006), No evidence for thick deposits of ice at the lunar south pole, Nature, 443, 835-837. Feldman, W., S. Maurice, B. B. A. B. Binder, R. Elphic, and D. Lawrence (1998), Fluxes of fast and epithermal neutrons from lunar prospector: Evidence for water ice at the lunar poles, Science, 281(5382), 1496–1500. Harmon, J. K., M. A. Slade, R. A. Velez, A. Crespo, M. J. Dryer, and J. M.Johnson (1994), Radar mapping of Mercury’s polar anomalies, Nature, 369, 213–215, doi:10.1038/369213a0. Harmon, J. K., P. J. Perillat, and M. A. Slade (2001), High-resolution radarimaging of Mercury’s north pole, Icarus, 149, 1 – 15, doi:10.1006/icar.2000.6544. Margot, J. L., D. B. Campbell, R. F. Jurgens, and M. A. Slade (1999), Topography of the lunar poles from radar interferometry: A survey of cold trap locations, Science, 284, 1658-1660. Nozette, S., C. L. Lichtenberg, P. D. Spudis, R. Bonner, W. Ort, E. Malaret, M. Robinson, and E. M. Shoemaker (1996), The Clementine Bistatic Radar Experiment, Science, 274, 1495–1498. Slade, M. A., B. J. Butler, and D. O. Muhleman (1992), Mercury radar imaging— Evidence for polar ice, Science, 258, 635–640.

Martian Polar Ice The icy polar deposits on Mars can be naturally divided into the polar layered deposits (PLD) and the residual ice caps (RIC) that partially cover them. In addition to these more permanent deposits, a seasonal ice cap of CO2 ice condenses from the atmosphere each winter season and sublimates away the following summer.

Good (although dated) introductory material Clifford, S. M., et al. (2000), The state and future of Mars polar science and exploration, Icarus, 144, 210–242. James, P. B., H. H. Kieffer, and D. A. Paige (1992), The seasonal cycle of carbon dioxide on Mars, in Mars, edited by H. H. Kieffer, B. M. Jakosky, C. W. Snyder, and M. S. Matthews, pp. 934-968, Univ. of Arizona Press. Tanaka, K. L., and D. Scott (1987), Geologic Map of the Polar Regions of Mars, U.S. Geol. Surv. Misc. Invest. Ser., Map I-1802-C. Thomas, P. C., S. W. Squyres, K. E. Herkenhoff, A. Howard, and B. C. Murray (1992), Polar deposits of Mars, in Mars, edited by H. H. Kieffer, B. M. Jakosky, C. W. Snyder, and M. S. Matthews, pp. 767–795, Univ. of Arizona Press. Vasavada, A. R., J. Williams, D. A. Paige, K. E. Herkenhoff, N. T. Bridges, R. Greeley, B. C. Murray, D. S. Bass, and K. S. McBride (2000), Surface properties of Mars’ polar layered deposits and polar landing sites, J. Geophys. Res., 105 (E3), 6961–6970.

Mars polar science has recently benefited immensely by three international conferences on Mars polar science and exploration. Special issues of Icarus were published for each of these conferences in volumes 144(2), 154(1) and 174(2). These volumes contain much of the recent work in this area.

Polar Layered Deposits:

The PLD at both poles are about 3km thick, 1000km across and almost pure H2O ice (with dust contaminants on the order of 1%). Their layered nature is thought to be driven by climatic change during their deposition, in a similar way to how past climate on Earth is recorded in terrestrial ice cores. Climatic variation on Mars is primarily driven by variations in the planet’s orbital elements and obliquity, analogous to Milankovitch cycles on the Earth. Recently identified mid-latitude ice-rich deposits are though to have originated from the PLD.

Ice-flow (or lack thereof) and internal structure in the polar layered deposits. Budd, W. F., D. Jenssen, J. H. I. Leach, I. N. Smith, and U. Radok (1986), The north polar cap of Mars as a steady-state system, Polarforschung, 56, 43–63. Byrne, S., and A. B. Ivanov (2004), The internal structure of the Martian south polar layered deposits, J. Geophys. Res., J. Geophys. Res., 109, E11001. Fishbaugh, K. E. and C. S. Hvidberg (2006), Martian north polar layered deposits stratigraphy: Implications for accumulation rates and flow, J. Geophys. Res., 111, 6012. Fisher, D. A. (1993), If Martian ice caps flow — Ablation mechanisms and appearance, Icarus, 105, 501–511. Fisher, D. A. (2000), Internal Layers in an “Accublation” Ice Cap: A Test for Flow, Icarus, 144, 289–294. Greve, R., R. A. Mahajan, J. Segschneider, and B. Grieger (2004), Evolution of the north- polar cap of Mars: a modeling study, Plan. Space Sci., 52, 775-787. Greve, R., V. Klemann, and D. Wolf (2003), Ice flow and isostasy of the north polar cap of Mars, Planet. Space Sci., 51, 193–204. Head, J. W. (2001), Mars: Evidence for geologically recent advance of the south polar cap, J. Geophys. Res., 106 (E5), 10,075–10,087. Hvidberg, C. S. (2003), Relationship between topography and flow in the north polar cap of Mars, Ann. Glaciol., 37, 363–369. Ivanov, A. B., and D. O. Muhleman (2000), The role of sublimation for the formation of the northern ice cap: Results from the Mars Orbiter Laser Altimeter, Icarus, 144, 436–448. Johnson, C. L., S. C. Solomon, J. W. Head, R. J. Philips, D. E. Smith, and M. T. Zuber (2000), Lithospheric loading by the northern polar cap on Mars, Icarus, 144, 313– 328. Nye, J. (2000), A flow model for the polar caps of mars, J. Glaciology, 46 (154), 438– 444. Nye, J. F., W. B. Durham, P. M. Schenk, and J. M. Moore (2000), The instability of a south polar cap on Mars composed of carbon dioxide, Icarus, 144, 449–455. Pathare, A. V. and D. A. Paige (2005), The effects of martian orbital variations upon the sublimation and relaxation of north polar troughs and scarps, Icarus, 174, 419-443.

Pathare, A. V., D. A. Paige, and E. Turtle (2005), Viscous relaxation of craters within the martian south polar layered deposits, Icarus, 174, 396-418. Picardi, G., and 33 colleagues (2005), Radar Soundings of the Subsurface of Mars, Science, 310, 1925-1928. Plaut, J. J., and 23 colleagues (2007), Subsurface Radar Sounding of the South Polar Layered Deposits of Mars, Science, 316, 92

North polar basal-unit Byrne, S., and B. C. Murray (2002), North polar stratigraphy and the paleo-erg of Mars, J. Geophys. Res., 107 (E6), 5044, doi:10.1029/2001JE001615. Edgett, K. S., R. M. E. Williams, M. C. Malin, B. A. Cantor, and P. C. Thomas (2003), Mars landscape evolution: influence of stratigraphy on geomorphology in the north polar region, Geomorphology, 52(3-4), 289-297. Fishbaugh, K. E. and J. W. Head (2005), Origin and characteristics of the Mars north polar basal unit and implications for polar geologic history, Icarus, 174, 444-474. Tanaka, K. L., J. A. Skinner, T. M. Hare, T. Joyal, and A. Wenker (2003), Resurfacing history of the northern plains of Mars based on geologic mapping of Mars Global Surveyor data, J. Geophys. Res., 108, 24-

Geologic Mapping and impact cratering Blasius, K. R., J. A. Cutts, and A. D. Howard (1982), Topography and stratigraphy of the Martian polar layered deposits, Icarus, 50, 140–160. Dial, A. L., Jr. (1984), Geologic Map of the Mare Boreum area of Mars, U.S. Geol. Surv. Misc. Invest. Ser., Map I-1640. Herkenhoff, K. E., and J. J. Plaut (2000), Surface Ages and Resurfacing Rates of the Polar Layered Deposits on Mars, Icarus, 144, 243–253. Kolb, E. J. and K. L. Tanaka (2001), Geologic History of the Polar Regions of Mars Based on Mars Global Surveyor Data. II. Amazonian Period, Icarus, 154, 22-39. Kolb, E. J. and K. L. Tanaka (2006), Accumulation and erosion of south polar layered deposits in the Promethei Lingula region, Planum Australe, Mars, Mars, 2, 1-9. Howard, A. D., J. A. Cutts, and K. R. Blasius (1982), Stratigraphic relationships within Martian polar cap deposits, Icarus, 50, 161–215. Koutnik, M., S. Byrne, and B. Murray (2002), South Polar Layered Deposits of Mars: The cratering record, J. Geophys. Res., 107 (E11), 5100, doi:10.1029/2001JE001805. Murray, B. C., L. A. Soderblom, J. A. Cutts, R. P. Sharp, D. J. Milton, and R. B. Leighton (1972), Geological framework of the south polar region of Mars, Icarus, 17, 328–345. Murray, B., M. Koutnik, S. Byrne, L. Soderblom, K. Herkenhoff, and K. L. Tanaka (2001), Preliminary Geological Assessment of the Northern Edge of Ultimi Lobe, Mars South Polar Layered Deposits, Icarus, 154, 80-97.

Plaut, J. J., R. Kahn, E. A. Guinness, and R. E. Arvidson (1988), Accumulation of sedimentary debris in the south polar region of Mars and implications for climate history, Icarus, 76, 357-377. Tanaka, K. L. and E. J. Kolb (2001), Geologic History of the Polar Regions of Mars Based on Mars Global Surveyor Data. I. Noachian and Hesperian Periods, Icarus, 154, 3-21. Tanaka, K. L., J. A. Skinner, T. M. Hare, T. Joyal, and A. Wenker (2003), Resurfacing history of the northern plains of Mars based on geologic mapping of Mars Global Surveyor data, J. Geophys. Res., 108, 24- Tanaka, K. L. (2005), Geology and insolation-driven climatic history of Amazonian north polar materials on Mars, Nature, 437, 991-994.

Connection of polar layered deposits (PLD) to climate Cutts, J. A., and B. H. Lewis (1982), Models of climate cycles recorded in Martian polar layered deposits, Icarus, 50, 216–244. Head, J. W., J. F. Mustard, M. A. Kreslavsky, R. E. Milliken, and D. R. Marchant (2003), Recent ice ages on Mars, Nature, 426, 797-802. Milkovich, S. M. and J. W. Head (2005), North polar cap of Mars: Polar layered deposit characterization and identification of a fundamental climate signal, J. Geophys. Res., 110, 1005. Mustard, J. F., C. D. Cooper, and M. K. Rifkin (2001), Evidence for recent climate change on Mars from the identification of youthful near-surface ground ice, Nature, 412, 4111-4114. Laskar, J., A. C. M. Correia, M. Gastineau, F. Joutel, B. Levrard, and P. Robutel (2004), Long term evolution and chaotic diffusion of the insolation quantities of Mars, Icarus, 170, 343-364. Laskar, J., B. Levrard, and J. F. Mustard (2002), Orbital forcing of the martian polar layered deposits, Nature, 419, 375-377. Levrard, B., F. Forget, F. Montmessin, and J. Laskar (2004), Recent ice-rich deposits formed at high latitudes on Mars by sublimation of unstable equatorial ice during low obliquity, Nature, 431, 1072-1075. Squyres, S. W. (1979), The evolution of dust deposits in the Martian north polar region, Icarus, 40, 244–261, 1979. Tanaka, K. L. (2005), Geology and insolation-driven climatic history of Amazonian north polar materials on Mars, Nature, 437, 991-994.

Formation of troughs, scarps and chasmata Benito, G., F. Mediavilla, M. Fernandez, A. Marquez, J. Martinez, and F. Anguita (1997), Chasma Boreale, Mars: A sapping and outflow channel with a tectono-thermal origin, Icarus, 129, 528–538.

Clifford, S. M. (1980), Chasma Boreale (85°N, 0°W): Remnant of a Martian jökulhlaup?, Bull. Am. Astron. Soc., 12, 678. Fishbaugh, K. E. and J. W. Head (2002), Chasma Boreale, Mars: Topographic characterization from Mars Orbiter Laser Altimeter data and implications for mechanisms of formation, J. Geophys. Res., 107, 2-1. Fisher, D. A. (1993), If Martian ice caps flow — Ablation mechanisms and appearance, Icarus, 105, 501–511. Fisher, D. A. (2000), Internal Layers in an “Accublation” Ice Cap: A Test for Flow, Icarus, 144, 289–294. Howard, A. D. (1978), Origin of the stepped topography of the Martian poles, Icarus, 34, 581–599. Ng, F. S. L. and M. T. Zuber (2006), Patterning instability on the Mars polar ice caps, J. Geophys.l Res., 111, 2005. Pelletier, J. D. (2004), How do spiral troughs form on Mars?, Geology, 32 (4), 365–367.

Surface Properties of the PLD Herkenhoff, K. E., and B. C. Murray (1990a), Color and albedo of the south polar layered deposits on Mars, J. Geophys. Res., 95 (B2), 1343–1358. Herkenhoff, K. E., and B. C. Murray (1990b), High-resolution topography and albedo of the South Polar layered deposits on Mars, J. Geophys. Res., 95 (B7), 14,511–14,529. Hofstadter, M. D., and B. C. Murray (1990), Ice sublimation and rheology — Implications for the Martian polar layered deposits, Icarus, 84, 352–361. Milkovich, S. and J.W. Head III (2006), Surface textures of Mars' north polar layered deposits: A framework for interpretation and future exploration, Mars 2, 21-45. Murray, B., M. Koutnik, S. Byrne, L. Soderblom, K. Herkenhoff, and K. L. Tanaka (2001), Preliminary geological assessment of the northern edge of Ultimi Lobe, Mars south polar layered deposits, Icarus, 154, 80–97. Paige, D. A., and K. D. Keegan (1994), Thermal and albedo mapping of the polar regions of Mars using Viking thermal mapper observations: 2. South polar region, J. Geophys. Res., 99 (E12), 25,993–26,013. Paige, D. A., J. E. Bachman, and K. D. Keegan (1994), Thermal and albedo mapping of the polar regions of Mars using Viking thermal mapper observations, 1, North polar region, J. Geophys. Res., 99, 25,959–25,991.

Eolian Processes and circumpolar dunes Herkenhoff, K. E., and A. R. Vasavada (1999), Dark material in the polar layered deposits and dunes on Mars, J. Geophys. Res., 104 (E7), 16,487–16,500. Howard, A. D. (2000), The role of eolian processes in forming surface features of the Martian polar layered deposits, Icarus, 144, 267–288.

Koutnik, M.R., S. Byrne, B.C. Murray, A.D. Toigo and Z.A. Crawford (2005), Eolian controlled modification of the martian south polar layered deposits, Icarus, 174, 490- 501. Lancaster, N., and R. Greeley (1990), Sediment volume in the north polar sand seas of Mars, J. Geophys. Res., 95, 10,921–10,927. Langevin, Y., F. Poulet, J.-P. Bibring, and B. Gondet (2005), Sulfates in the North Polar Region of Mars Detected by OMEGA/Mars Express, Science, 307, 1584-1586. Saunders, R. S., and D. T. Blewett (1987), Mars north polar dunes: Possible formation from low density sedimentary aggregates, Astron. Vestn., 21, 181–188. Thomas, P. C., and C. Weitz (1989), Sand dune materials and polar layered deposits on Mars, Icarus, 81, 185–215. Tsoar, H., R. Greeley (1979), and A. R. Peterfreund, Mars: The north polar sand sea and related wind patterns, J. Geophys. Res., 84, 8167–8180.

Residual Ice Caps: The residual ice caps (RIC) that partially cover the layered deposits are composed of ~1m of clean large-grained H2O ice at the northern pole and 2-10m of clean CO2 ice at the southern pole. The northern RIC has a homogeneous decameter scale texture whereas the southern RIC processes a wide range of geomorphologies such as flat-floored pits and linear ridges at multiple scales. Features on the southern RIC have been observed to change in size with time as the volatile CO2 material is redistributed by ablation of the ice.

Geomorphology, composition and changes within the Southern Residual Ice Cap Bibring, J.-P., and 13 colleagues (2004), Perennial water ice identified in the south polar cap of Mars, Nature, 428, 627-630. Byrne, S., and A. P. Ingersoll (2003a), A Sublimation Model for Martian South Polar Ice Features, Science, 299, 1051–1053. Byrne, S., and A. P. Ingersoll (2003b), Martian climatic events on timescales of centuries: Evidence from feature morphology in the residual south polar cap, Geophys. Res. Lett., 30 (13). Kieffer, H. H., (1979), Mars south polar spring and summer temperatures — A residual CO2 frost, J. Geophys. Res., 84, 8263–8288. Jakosky, B. M., and R. M. Haberle (1990), Year-to-Year Instability of the Mars South Polar Cap, J. Geophys. Res., 95, 1359-1365. Malin, M. C., M. A. Caplinger, and S. D. Davis (2001), Observational evidence for an active surface reservoir of solid carbon dioxide on mars, Science, 294, 2146-2148. Prettyman, T. H., Feldman, W. C., Mellon, M. T., McKinney, G. W., Boynton, W. V., Karunatillake, S., Lawrence, D. J., Maurice, S., Metzger, A. E., Murphy, J. R., Squyres, S. W., Starr, R. D., and Tokar, R. L. (2004), Composition and structure of the Martian surface at high southern latitudes from neutron spectroscopy, J. Geophys. Res. 109, 5001. Thomas P. C., M. C. Malin, K. S. Edgett, M. H. Carr, W. K. Hartmann, A. P. Ingersoll, P. B. James, L. A. Soderblom, J. Veverka, and R. Sullivan (2000), North-south geological differences between the residual polar caps on Mars, Nature, 404, 161- 164. Thomas, P. C., M. C. Malin, P. B. James, B. A. Cantor, R. M. E. Williams, and P. Gierasch (2005),South polar residual cap of Mars: Features, stratigraphy, and changes. Icarus 174, 535-559. Titus, T. N., H. H. Kieffer, and P. R. Christensen (2003), Exposed Water Ice Discovered near the South Pole of Mars, Science, 299, 1048–1051. Tokar, R. L., R. C. Elphic, W. C. Feldman, H. O. Funsten, K. R. Moore, T. H. Prettyman, and R. C. Wiens (2003), Mars odyssey neutron sensing of the south residual polar cap, Geophys. Res. Lett., 30 (13), 1677, doi:10.1029/2003GL017316, 2003.

Geomorphology and composition of the Northern Residual Ice Cap Arthern, R. J., D. P. Winebrenner, and E. D. Waddington (2000), Densification of Water Ice Deposits on the Residual North Polar Cap of Mars, Icarus, 144, 367-381. Bass, D. S., Herkenhoff, K. E., and Paige, D. A., 2000. Variability of Mars' North Polar Water Ice Cap. I. Analysis of Mariner 9 and Viking Orbiter Imaging Data. Icarus 144, 382-396. Byrne, S., M.T. Zuber, and G.A. Neumann (2006), Interannual and Seasonal Behavior of Martian Residual Ice-Cap Albedo, Planetary Space Sci., In Press. Fisher, D. A., D. P. Winebrenner, and H. Stern (2002), Lineations on the “White” Accumulation Areas of the Residual Northern Ice Cap of Mars: Their Relation to the “Accublation” and Ice Flow Hypothesis, Icarus, 159, 39-52. Kieffer, H. H., S. C. Chase, T. Z. Martin, E. D. Miner, and F. D. Palluconi (1976), Martian north pole summer temperatures – Dirty water ice, Science, 194, 1341. Kieffer, H. H., (1990), H2O grain size and amount of dust in Mars residual north polar cap, J. Geophys. Res., 96, 1481–1493. Langevin, Y., F. Poulet, J.P. Bibring, B. Schmitt, S. Doute and B. Gondet (2005), Summer Evolution of the North Polar Cap of Mars as Observed by OMEGA/Mars Express, Science, 307, 1581-1584. Snyder Hale, A., D.S. Bass and L.K. Tamppari (2005), Monitoring the perennial martian northern polar cap with MGS MOC, Icarus, 174, 502-512. Thomas P. C., M. C. Malin, K. S. Edgett, M. H. Carr, W. K. Hartmann, A. P. Ingersoll, P. B. James, L. A. Soderblom, J. Veverka, and R. Sullivan (2000), North-south geological differences between the residual polar caps on Mars, Nature, 404, 161- 164.

Seasonal Ice Caps:

The seasonal caps of Mars lock up about a third of the atmospheric CO2 on the planet and extend from the winter pole to the mid-latitudes. Recent data has shown a variety of unique phenomena associated with these seasonal deposits.

Aharonson, O., M. T. Zuber, D. E. Smith, G. A. Neumann, W. C. Feldman, and T. H. Prettyman (2004), Depth, distribution, and density of CO2 deposition on Mars, J. Geophys. Res., 109, E05004, doi:10.1029/2003JE002223. Benson, J. L. and P. B. James (2005), Yearly comparisons of the martian polar caps: 1999-2003 Mars Orbiter Camera observations, Icarus, 174, 513-523. Colaprete, A., Barnes, J. R., Haberle, R. M., Hollingsworth, J. L., Kieffer, H. H., and Titus, T. N. (2005). Albedo of the south pole on Mars determined by topographic forcing of atmosphere dynamics. Nature, 435, 184-188. Kieffer, H.H. (2007), Cold Jets in the Martian Polar Caps, J. Geophys. Res., In Press. Kieffer, H. H. and T. N. Titus (2001), TES Mapping of Mars' North Seasonal Cap, Icarus, 154, 162-180. Kieffer, H. H., T. N. Titus, K. F. Mullins, and P. R. Christensen (2000), Mars south polar spring and summer behavior observed by TES: Seasonal cap evolution controlled by frost grain size, J. Geophys. Res., 105(E4), 9653-9699. Kieffer, H. H., P. R. Christensen, and T. N. Titus (2006), CO2 jets formed by sublimation beneath translucent slab ice in Mars' seasonal south polar ice cap, Nature, 442, 793- 796. James, P. B. and B. A. Cantor (2001), Martian North Polar Cap Recession: 2000 Mars Orbiter Camera Observations, Icarus, 154, 131-144. Langevin, Y., S. Doute, M. Vincendon, F. Poulet, J.-P. Bibring, B. Gondet, B. Schmitt, and F. Forget (2006), No signature of clear CO2 ice from the `cryptic' regions in Mars' south seasonal polar cap, Nature, 442, 790-792. Leighton, R. B., and B. C. Murray (1966), Behavior of carbon dioxide and other volatiles on Mars, Science, 153, 136-144. Piqueux, S., S. Byrne, and M.I. Richardson (2003), The sublimation of Mars southern CO2 ice cap and the formation of "spiders", J. Geophys. Res., 108(E8), 5084. Smith, D. E., Zuber, M. T., and Neumann, G. A., 2001. Seasonal Variations of Snow Depth on Mars. Science 294, 2141-2146. Titus, T. N., H. H. Kieffer, K. F. Mullins, and P. R. Christensen (2001), TES premapping data: Slab ice and snow flurries in the Martian north polar night, J. Geophys. Res., 106, 23181-23196.