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- Author or Editor: C. R. Stearns x
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Abstract
Air temperature (T A ) records from automatic weather stations (AWS) in central Greenland and associated Special Sensor Microwave/Imager (SSM/I) brightness temperature (T B ) data (37 GHz, vertical polarization) have been used to create a composite, daily, monthly, and annual average temperature record of the Greenland summit for the period 1987–1994. The record is derived primarily from near-surface temperatures from a single station; AWS Cathy (May 1987 to May 1989), which was moved 28 km and became AWS Kenton (starting in June 1989 and continuing). The Cathy daily average T A record has been converted to the equivalent basis of Kenton by a technique based on the ratio of the contemporaneous daily average T B data from the two locations. The accuracy of this technique has been statistically tested using 16 months of contemporaneous T A and T B data from the GISP2 and Kenton AWS. The resulting composite temperature record provides a multiyear dataset for comparison to other climate records from the Greenland summit.
Abstract
Air temperature (T A ) records from automatic weather stations (AWS) in central Greenland and associated Special Sensor Microwave/Imager (SSM/I) brightness temperature (T B ) data (37 GHz, vertical polarization) have been used to create a composite, daily, monthly, and annual average temperature record of the Greenland summit for the period 1987–1994. The record is derived primarily from near-surface temperatures from a single station; AWS Cathy (May 1987 to May 1989), which was moved 28 km and became AWS Kenton (starting in June 1989 and continuing). The Cathy daily average T A record has been converted to the equivalent basis of Kenton by a technique based on the ratio of the contemporaneous daily average T B data from the two locations. The accuracy of this technique has been statistically tested using 16 months of contemporaneous T A and T B data from the GISP2 and Kenton AWS. The resulting composite temperature record provides a multiyear dataset for comparison to other climate records from the Greenland summit.
Abstract
Reduced visibility due to blowing snow can severely hinder aircraft operations in the Antarctic. Wind speeds in excess of approximately 7–13 m s−1 can result in blowing snow. The ability to forecast high wind speed events can improve the safety and efficiency of aircraft activities. The placement of automatic weather stations to the south (upstream) of the Pegasus Runway, and other airfields near McMurdo Station, Antarctica, can provide the forecaster the information needed to make short-term (3–6 h) forecasts of high wind speeds, defined in this study to be greater than 15 m s−1. Automatic weather station (AWS) data were investigated for the period of 1 January 1991 through 31 December 1996, and 109 events were found that had high wind speeds at the Pegasus North AWS site. Data from other selected AWS sites were examined for precursors to these high wind speed events. A temperature increase was generally observed at most sites before such an event commenced. Increases in the temperature difference between the Pegasus North AWS and the Minna Bluff AWS and increasing pressure differences between other AWS sites were also common features present before the wind speed began to increase at the Pegasus North site. Many times, changes in one or more of these parameters occurred hours before the wind began to increase at the Pegasus North site. Monitoring of these parameters can lead to an improved 3–6-h forecast of these high wind speed events at Pegasus Runway, Antarctica.
Abstract
Reduced visibility due to blowing snow can severely hinder aircraft operations in the Antarctic. Wind speeds in excess of approximately 7–13 m s−1 can result in blowing snow. The ability to forecast high wind speed events can improve the safety and efficiency of aircraft activities. The placement of automatic weather stations to the south (upstream) of the Pegasus Runway, and other airfields near McMurdo Station, Antarctica, can provide the forecaster the information needed to make short-term (3–6 h) forecasts of high wind speeds, defined in this study to be greater than 15 m s−1. Automatic weather station (AWS) data were investigated for the period of 1 January 1991 through 31 December 1996, and 109 events were found that had high wind speeds at the Pegasus North AWS site. Data from other selected AWS sites were examined for precursors to these high wind speed events. A temperature increase was generally observed at most sites before such an event commenced. Increases in the temperature difference between the Pegasus North AWS and the Minna Bluff AWS and increasing pressure differences between other AWS sites were also common features present before the wind speed began to increase at the Pegasus North site. Many times, changes in one or more of these parameters occurred hours before the wind began to increase at the Pegasus North site. Monitoring of these parameters can lead to an improved 3–6-h forecast of these high wind speed events at Pegasus Runway, Antarctica.
