Assessment of the evolution of the Northeastern Russia glacier systems using regular grid meteorological data

Abstract

A methodical approach is proposed for calculating the equilibrium line altitudeHELAof glacier systems (on the example of the Northeastern Russia) on the basis of the characteristics that determine it in time and space: from the archive of temperature and precipitation at the grid points (the UDel archive, Delaware University). This data is used in the equation of mass balance of the glacier systems for the calculation of its components. As a result, the output is the inter-annual series of deviations ofHELAfrom the mean value and the ratio between accumulation and solid precipitation in the regular grids over the glacial systems. By the longterm series of theHELAdeviations the periods of minimum and maximumHELAstate were revealed for various glacial systems, as well as linear trends of these series. This made us possible to evaluate theHELAtrends in the future using the linear regression method. The sensitivity of the method of the initial parameters – the mean values of the summer air temperature, solid precipitation and theHELAvalue, received independently, have been estimated. Thus, the method allows detailing theHELAchanges in space with the resolution of the archive used, and in time for each year of the selected climatic period.