Assembly of a twenty-year record of hourly meteorological data for Peyto Glacier basin with modelled mass balance and runoff time series.

English Abstract:

The first complete year of recorded hourly global radiation, air temperature, relative humidity, wind speed and precipitation for the Peyto Glacier basin was obtained in 1992, continuing to the present day, thus distinguishing it as one of the longer such glacierized basin records in the world. One air temperature sensor has remained the same throughout this period, never to change position, but all others have changed due to sensor failure, fatigue and equipment updates. Also, there are significant gaps in the records of 1998, 1999 and 2009 due to power failures, thus requiring substitute values for modelling purposes. Most problematic is the precipitation record, the first half of which comes from an old Fischer-Porter gauge, using unconventional procedures, the second from a modern Geonor gauge with standard data processing rules.

Discounting the three years when data gaps occurred, mean annual air temperature from 1992 to 2011 is -1.27 ±0.68 ˚C, the first decade of record almost 0.5 ˚C colder than the second. Mean yearly total precipitation is 1159 ±239 mm, approximately 64 ±11 % of which falls as snow according to a <1.5 ˚C threshold. The first ten years of record, solely from the Fischer-Porter gauge, suggest 1205 ±302 mm a^-1 of precipitation, while the Geonor record of the second ten years indicates 1118 ±175 mm a^-1, the larger deviation a possible reflection of procedural differences. The data are used in conjunction with a LiDAR derived DEM to drive a 25 m resolution raster based mass balance model of the glacier surface which is applied cumulatively to estimate winter and summer mass balances over the twenty-year period, as well as daily summer runoff.