HR: 0800h
AN: U21A-0803 [Abstracts]
TI: 1935-2004 Water Vapor Trends at the Summit of Mount Washington, NH
AU: * Seidel, T M
EM: tseidel@mountwashington.org
AF: Mount Washington Observatory, PO Box 34
2779 White Mountain Highway, North Conway, NH 03860
United States
AU: Grant, A N
EM: andrea.grant@env.ethz.ch
AF: Mount Washington Observatory, PO Box 34
2779 White Mountain Highway, North Conway, NH 03860
United States
AU: Grant, A N
EM: andrea.grant@env.ethz.ch
AF: Eidgenössische Technische Hochschule, Institute for Atmospheric and Climate Science, Zürich,
CH-8092
Switzerland
AU: Pszenny, A A
EM: alex.pszenny@unh.edu
AF: Mount Washington Observatory, PO Box 34
2779 White Mountain Highway, North Conway, NH 03860
United States
AU: Pszenny, A A
EM: alex.pszenny@unh.edu
AF: University of New Hampshire, Institute for the Study of Earth, Oceans, and Space, Durham, NH 03824
AB:
As part of an ongoing effort to digitize and analyze the unique historical climate record from the summit of Mount
Washington, water vapor mixing ratios calculated from synoptic (six-hourly) sling psychrometer and related data will be
presented. The Mount Washington Observatory, located at 44°16'N, 71°18'W, 1914 m ASL, has been recording
meteorological conditions since 1932. A continuous record of hourly and synoptic data exists from 1935 to the present.
Previous work with hourly temperature data has shown an increase in annual temperature of 0.3°C over this 69-year
interval, with larger increases during spring and winter, and a decrease in diurnal temperature range (A. Grant et al., J.
Climate, in press). Preliminary examination of the synoptic psychrometric data suggests a decrease in annual dew point of
approximately 0.4°C, with larger decreases in fall and winter than during the other seasons. Decreasing dew points are
expected under two conditions: drier air or constant water vapor with increasing temperature. Other dew point climatologies
of the continental United States for the second half of the 20th century have shown mixed results, with increased dew points
evident at some stations, decreased dew points at others, and no clear regional patterns.
DE: 1637 Regional climate change
SC: Union [U]
MN: Fall Meeting 2005