Downscaling of the global climate model data for the mass balance calculation of mountain glaciers

In this paper, we consider a hybrid method of downscaling of the GCM‑generated meteorological fields to the characteristic spatial resolution which is usually used for modeling of a single mountain glacier mass balance. The main purpose of the study is to develop a reliable forecasting method to eva...

Full description

Saved in:
Bibliographic Details
Main Authors: P. A. Morozova, O. O. Rybak
Format: Article
Language:Russian
Published: Nauka 2017-12-01
Series:Лëд и снег
Subjects:
Online Access:https://ice-snow.igras.ru/jour/article/view/412
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849399868455387136
author P. A. Morozova
O. O. Rybak
author_facet P. A. Morozova
O. O. Rybak
author_sort P. A. Morozova
collection DOAJ
description In this paper, we consider a hybrid method of downscaling of the GCM‑generated meteorological fields to the characteristic spatial resolution which is usually used for modeling of a single mountain glacier mass balance. The main purpose of the study is to develop a reliable forecasting method to evaluate future state of moun‑ tain glaciation under changing climatic conditions. The method consists of two stages. In the first or dynamical stage, we use results of calculations of the regional numerical model HadRM3P for the Black Sea‑Caspian region with a spatial resolution of 25 km [22]. Initial conditions for the HadRM3P were provided by the GCM devel‑ oped in the Institute of Numerical Mathematics of RAS (INMCM4) [18]. Calculations were carried out for two time periods: the present climate (1971–2000) and climate in the late 21st century (2071–2100) according to the scenario of greenhouse gas emissions RCP 8.5. On the second stage of downscaling, further regionalization is achieved by projecting of RCM‑generated data to the high‑resolution (25 m) digital altitude model in a domain enclosing a target glacier. Altitude gradients of the surface air temperature and precipitation were derived from the model data. Further on, both were corrected using data of observations. Incoming shortwave radiation was calculated in the mass balance model separately, taking into account characteristics of the slope, i.e. exposition and shading of each cell. Then, the method was tested for glaciers Marukh (Western Caucasus) and Jankuat (Central Caucasus), both for the present‑day and for future climates. At the end of the 21st century, the air tem‑ perature rise predicted for the summer months was calculated to be about 5–6 °C, and the result for the winter to be minus 2–3 °C. Change in annual precipitation is not significant, less than 10%. Increase in the total short‑ wave radiation will be about 5%. These changes will result in the fact that the snow line will be higher than the body of the glacier itself. This will inevitably cause degradation of the glacier and its gradual disappearance. The main contribution to the glacier shrinking and disappearance will be made by air temperature rise, because it will affect the change in the ratio of the areas of ablation and accumulation. Besides, a rise of temperature will increase the average melting season duration. These are, of cause, preliminary results just to illustrate how the downscaling method works. We did not take into account dynamic effects and gradual reducing of the glaciated area. In future, we plan to couple mass balance and dynamical models [17] and to adjoin them with downscaled climate change in order to account for transient glacier changes.
format Article
id doaj-art-4cc59671ad924d9e8bc63edc2ed78761
institution Kabale University
issn 2076-6734
2412-3765
language Russian
publishDate 2017-12-01
publisher Nauka
record_format Article
series Лëд и снег
spelling doaj-art-4cc59671ad924d9e8bc63edc2ed787612025-08-20T03:38:14ZrusNaukaЛëд и снег2076-67342412-37652017-12-0157443745210.15356/2076-6734-2017-4-437-452337Downscaling of the global climate model data for the mass balance calculation of mountain glaciersP. A. Morozova0O. O. Rybak1Institute of Geography, Russian Academy of Sciences; Branch of Institute of Natural and Technical Systems.Branch of Institute of Natural and Technical Systems; Scientific Research Center, Russian Academy of Sciences; Earth System Sciences & Departement Geografie, Vrije Universiteit Brussel.In this paper, we consider a hybrid method of downscaling of the GCM‑generated meteorological fields to the characteristic spatial resolution which is usually used for modeling of a single mountain glacier mass balance. The main purpose of the study is to develop a reliable forecasting method to evaluate future state of moun‑ tain glaciation under changing climatic conditions. The method consists of two stages. In the first or dynamical stage, we use results of calculations of the regional numerical model HadRM3P for the Black Sea‑Caspian region with a spatial resolution of 25 km [22]. Initial conditions for the HadRM3P were provided by the GCM devel‑ oped in the Institute of Numerical Mathematics of RAS (INMCM4) [18]. Calculations were carried out for two time periods: the present climate (1971–2000) and climate in the late 21st century (2071–2100) according to the scenario of greenhouse gas emissions RCP 8.5. On the second stage of downscaling, further regionalization is achieved by projecting of RCM‑generated data to the high‑resolution (25 m) digital altitude model in a domain enclosing a target glacier. Altitude gradients of the surface air temperature and precipitation were derived from the model data. Further on, both were corrected using data of observations. Incoming shortwave radiation was calculated in the mass balance model separately, taking into account characteristics of the slope, i.e. exposition and shading of each cell. Then, the method was tested for glaciers Marukh (Western Caucasus) and Jankuat (Central Caucasus), both for the present‑day and for future climates. At the end of the 21st century, the air tem‑ perature rise predicted for the summer months was calculated to be about 5–6 °C, and the result for the winter to be minus 2–3 °C. Change in annual precipitation is not significant, less than 10%. Increase in the total short‑ wave radiation will be about 5%. These changes will result in the fact that the snow line will be higher than the body of the glacier itself. This will inevitably cause degradation of the glacier and its gradual disappearance. The main contribution to the glacier shrinking and disappearance will be made by air temperature rise, because it will affect the change in the ratio of the areas of ablation and accumulation. Besides, a rise of temperature will increase the average melting season duration. These are, of cause, preliminary results just to illustrate how the downscaling method works. We did not take into account dynamic effects and gradual reducing of the glaciated area. In future, we plan to couple mass balance and dynamical models [17] and to adjoin them with downscaled climate change in order to account for transient glacier changes.https://ice-snow.igras.ru/jour/article/view/412air temperaturecaucasusclimate scenariodownscalingglaciermass balanceprecipitationsregional model
spellingShingle P. A. Morozova
O. O. Rybak
Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
Лëд и снег
air temperature
caucasus
climate scenario
downscaling
glacier
mass balance
precipitations
regional model
title Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
title_full Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
title_fullStr Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
title_full_unstemmed Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
title_short Downscaling of the global climate model data for the mass balance calculation of mountain glaciers
title_sort downscaling of the global climate model data for the mass balance calculation of mountain glaciers
topic air temperature
caucasus
climate scenario
downscaling
glacier
mass balance
precipitations
regional model
url https://ice-snow.igras.ru/jour/article/view/412
work_keys_str_mv AT pamorozova downscalingoftheglobalclimatemodeldataforthemassbalancecalculationofmountainglaciers
AT oorybak downscalingoftheglobalclimatemodeldataforthemassbalancecalculationofmountainglaciers