TITLE Precipitation scenarios for Norway Empirical downscaling from the ECHAM4/OPYC3 GSDIO integration AUTHORS

The 2m temperature and the SLP field from the ECHAM4/OPYC3 GSDIO integration (which includes effects of greenhouse-gases and tropospheric ozon, as well as direct and indirect effects of sulphur aeroseols) were used as predictors for empirical downscaling of local monthly precipitation over Norway du...

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Bibliographic Details
Main Authors: I. Hanssen-bauer, O. E. Tveito, E. J. Førl
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
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Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.607.6408
http://met.no/Forskning/Publikasjoner/Publikasjoner_2001/filestore/klima-2001-10.pdf
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Summary:The 2m temperature and the SLP field from the ECHAM4/OPYC3 GSDIO integration (which includes effects of greenhouse-gases and tropospheric ozon, as well as direct and indirect effects of sulphur aeroseols) were used as predictors for empirical downscaling of local monthly precipitation over Norway during the period 1870-2050. Temperature was used as predictor in addition to the SLP-field because it is crucial to include a predictor which carries the greenhouse signal. The use of temperature as an additional predictor gave improved results in autumn, winter, and partly during spring. In summer, however, it led to physically suspect results, and temperature was thus skipped as predictor for the summer months. The empirically downscaled precipitation series indicate an increase in the average annual precipitation of 0.3 to 2.7 % per decade during the coming 50 years at the Norwegian mainland, and about 1.5 % per decade on Svalbard. The projected increase rates are generally smallest in south-eastern Norway, where they are not statistically significant (5 % level) and largest along the north-western and western coast, where they are highly significant. In winter, statistically significant positive trends (+1.8 to 3.2 % per decade) are found all over the country. The largest increase rates are found in