Top of this page

Photograph looking north-north-east at the meteorology station at Gulkana Glacier on April 20, 1995. The station is located at 1,480 meters altitude on the crest of a wind-swept, ice-cored moraine along the eastern boundary of the glacier. The thin snow cover shown at the site is typical of the winter season and does not result in significant seasonal change to the ground clearance of the sensors. The small white vented shelter to the left in the photograph houses the temperature sensors. Behind it can be seen the eastern portion of the lower glacier. The precipitation gage, shown in the center of the photograph, consists of a steel storage tank that tapers to a conical orifice, 0.305 meters in diameter, 3 meters above the ground. A modified Nipher shield is installed around the orifice to improve the catch efficiency during windy conditions and to help prevent snow from capping the orifice. The panels of the shield are hinged near the top so they can swing in the wind to help shed snow. (Note that one panel of the shield is missing in the photograph.) The upper section of the gage is painted dark green to absorb sunlight and prevent ice and snow from accumulating on the inside walls of the gage. The white color of the lower section of the gage reduces solar warming and expansion of the stored antifreeze-water solution. The storage tank contains a self-mixing antifreeze. An oil layer prevents evaporation of antifreeze and stored precipitation. A float is used to sense changes in the volume of stored precipitation and hence determine daily precipitation. The gray box on the back side of the gage houses the recording instrumentation. The 55 gallon barrel to the right of the gage stores extra antifreeze.

This meteorological equipment has remained essentially the same since the station began operation in 1967. In September 1995, two digital temperature sensors, a digital wind speed sensor, digital data logger, and satellite telemetry were added to the station.

(Click on image for enlargement, 101 KB.)

Maintainer: Rod March
Last update: Thursday, January 15, 2004 04:44 PM
URL: http://ak.water.usgs.gov/glaciology/gulkana/met/MetStationPhoto950420.htm