| Autor: |
Ólafur Rögnvaldsson, Jona Finndís Jónsdóttir, Haraldur Ólafsson |
| Jazyk: |
angličtina |
| Rok vydání: |
2007 |
| Předmět: |
|
| Zdroj: |
Meteorologische Zeitschrift, Vol 16, Iss 1, Pp 71-85 (2007) |
| Druh dokumentu: |
article |
| ISSN: |
0941-2948 |
| DOI: |
10.1127/0941-2948/2007/0174 |
| Popis: |
Atmospheric flow over Iceland has been simulated for the period September 1987 through June 2003, using the PSU/NCAR MM5 mesoscale model driven by initial and boundary data from the European Centre for Medium-range Weather Forecasts (ECMWF). The simulated precipitation is compared with two types of indirect precipitation observations. Firstly, snow accumulation on two large ice caps in SE-Iceland and on two large glaciers in central Iceland. Secondly, model output is used as input to the WaSiM-ETH hydrological model to calculate and compare the runoff with observed runoff from six watersheds in Iceland for the water years 1987-2002. Model precipitation compares favourably with both types of validation data. The seasonal and inter-annual variability of precipitation is investigated at low as well as high altitudes. The simulations reveal a negative trend in the winter precipitation in W-Iceland, but a positive trend in the ratio of lowland precipitation to mountain precipitation in E-Iceland. There is in general a substantial inter-annual variability in the ratio of lowland precipitation to precipitation in the mountains, especially in E-Iceland, emphasizing the limitation of precipitation observations in the lowlands as a proxy for precipitation in the mountains. In order to assess the impact of orography on the precipitation climate of Iceland, precipitation is simulated with flat Iceland and compared to a simulation with true orography. It is found that the mountains contribute to a total increase of precipitation in Iceland of the order of 40 %. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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