HR: 0800h
AN: GC41A-0105 [Abstracts]
TI: 1935-2006 Duration of Snowcover and Growing Degree Trends from the Summit and Base of
Mount Washington, NH
AU: * Seidel, T M
EM: tseidel@mountwashington.org
AF: Mount Washington Observatory, PO Box 2310, North Conway, NH 03860, United States
AU: Soboleski, R
EM: rmsobo@hotmail.com
AF: Mount Washington Observatory, PO Box 2310, North Conway, NH 03860, United States
AU: Crete, E
EM: erl3@unh.edu
AF: Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse
Hall,
39 College Road, Durham, NH 03824-3525, United States
AU: Weihrauch, D M
EM: dweihrauch@outdoors.org
AF: Research Department, Appalachian Mountain Club, PO Box 298, Gorham, NH 03581,
United States
AU: Pzsenny, A A
EM: alex.pszenny@unh.edu
AF: Mount Washington Observatory, PO Box 2310, North Conway, NH 03860, United States
AU: Pzsenny, A A
EM: alex.pszenny@unh.edu
AF: Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Morse
Hall,
39 College Road, Durham, NH 03824-3525, United States
AU: Kimball, K D
EM: KKimball@outdoors.org
AF: Research Department, Appalachian Mountain Club, PO Box 298, Gorham, NH 03581,
United States
AU: Murray, G
EM: gmurray@outdoors.org
AF: Research Department, Appalachian Mountain Club, PO Box 298, Gorham, NH 03581,
United States
AB:
Start and end dates of continuous snowcover, growing degree days and thawing degree days were calculated
using the 71-year climate record from the summit of Mount Washington (1914m ASL), NH. Preliminary results
show the start of continuous snowcover (defined as ≥ 2.54cm of snow on ground) on the summit of Mount
Washington occurs later in the autumn by 2.1 days decade -1 and ends slightly later in the spring by 0.3 days
decade -1, a net decrease in continuous snowcover of 1.8 days decade -1. The trend of a shorter snow
season is more pronounced for the date of first and last observed snow on the ground; the first snow occurring
6.7 days decade -1 later in the autumn and last snow 3.3 days decade -1 earlier in the spring.
Similarly, using hourly values, cumulative thawing degree days (>0° C) and growing degree days (>5°
C) exhibit spring warming; for example the date at which the cumulative thawing degree days = 50 is occurring
earlier by 1.1 days decade -1. There is a slight discrepancy between the later continuous snowcover
persistence in the spring and the other metrics that we are examining. The above metrics will also be presented
from for the eastern base of the mountain, Pinkham Notch, New Hampshire (619m ASL), and compared with
these summit data. These results provide insight into how the remnant islands of Arctic flora surviving on the
Northeast's higher peaks are now and will be challenged in the future.
DE: 0736 Snow (1827, 1863)
DE: 0740 Snowmelt
DE: 1630 Impacts of global change (1225)
DE: 1637 Regional climate change
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting