ASTER and DEM Change Assessment of Glaciers Near Hoodoo Mountain, British Columbia, Canada
Global Land Ice Measurements From Space
Hoodoo Mountain ice cap, Hoodoo Glacier, and Twin glacier are located about 250 km southeast of Juneau, Alaska, in the Coast Mountains (near 56.8°N, 131.3°W, northwestern British Columbia). Several outlet valley glaciers flow towards the south from an ice cap centered approximately 16 km northeast of Hoodoo Mountain; some glaciers are relatively clean ice, while others are heavily debris covered. Hoodoo and Twin glaciers have a Pleistocene and Early Holocene record of interaction with a trachyte volcano, Hoodoo Mountain (which is still ice capped), though they have retreated far enough that future eruptions are unlikely to produce direct lava-ice interactions from anything other than long-lived lava flows. Our analysis shows retreat and accelerating thinning for valley glaciers within this study; this behavior appears to be climatically driven. However, the small ice cap on Hoodoo Mountain seems to be insensitive to climate change; rather, the ice cap's extent is controlled mainly by the shape and elevation of the landform. The overall average mass balance of the combined set of glaciers in the study region was about -840 ± 180 kg m-2 yr-1 for the period from 1965 to 2005, though different glaciers have specific mass balances ranging from near zero (i.e., in local balance) to -2,400 kg m-2 yr-1. Furthermore, the documented increase in the rate of thinning indicates an increasing magnitude of negative balances over the four decades of the study period. Aside from the Hoodoo Mountain ice cap (which is close to a balance state, except at the very edges on the cliffs, where retreat and thinning have taken place), the prevalent glacier thinning and retreat of the Hoodoo Mountain area is similar to most other maritime parts of the Canadian Cordillera (see Chapter 14 of this book by Wheate et al.). Hoodoo Mountain is a classic flat-topped glacio volcanic edifice (tuya), and was shaped when ice was much thicker within the massive Cordilleran Ice Sheet. Continuing glacial retreat from the flanks of Hoodoo Mountain offers new possibilities for the study of fresh exposures of materials formed by ice interactions with a rare lava type.
Kargel, Jeffrey S., Gregory J. Leonard, Roger D. Wheate, and Benjamin Edwards. “ASTER and DEM Change Assessment of Glaciers Near Hoodoo Mountain, British Columbia, Canada.” In Global Land Ice Measurements From Space, edited by Jeffrey S. Kargel, Gregory J. Leonard, Michael P. Bishop, Andreas Kääb, and Bruce H. Raup, 353-73. Heidelberg: Springer, 2014.