Calculation of degree-days for glacier-climate research

Abstract

The conventional way ol calculating positive degree-days is by summation ol daily temperature series, but this is inelficient in terms of data volume and computing requirements.An alternative method for calculating degree-days from monthly mean temperature is developed lrom statistical considerations and is tested with data lrom the Swiss Alps and from West Greenland.For the calculation ol seasonal or annual degree-days, the errors in the method are small compared to the errors involved in estimating glacier ablation lrom degree-day sums.The glaciologi- cal implications ol the relationship between positive degree-days and mean temperature are also discussed.