Maj-Lena Finnander Linderson
Senior lecturer
The Spatial Distribution of Precipitation in Scania, Southern Sweden. Observations, model simulations and statistical downscaling.
Author
Summary, in English
It was found that the spatial co-variability of the monthly precipitation within Scania is high. Topography is the major factor influencing the precipitation distribution. Furthermore, there is a significant difference between the southeastern and the northwestern part of Scania related to the land/sea distribution in the area. Consequently, the annual mean precipitation in Scania has a spatial variation with a typical length scale of 20-35 km elongated in the N/NW to S/SE direction. The spatial patterns are not well captured by the RCA1 dynamical downscaling model. This may partly be caused by a too coarse resolution (44 km) of the RCA1. In total, 80-90% of the observed monthly meso-scale precipitation variation of Scania can successfully be related to, and explained by, the regional atmospheric circulation indices. This indicates that the regional atmospheric circulation is an important predictor in the statistical downscaling of precipitation. The daily precipitation patterns are also largely influenced by the pressure patterns in regional scale. Daily mean precipitation and the frequency of wet-days could be successfully modelled by the statistical downscaling procedure, using the monthly predictors of large-scale precipitation, relative humidity and atmospheric circulation indices. The downscaled scenario shows a significant increase of the annual daily mean precipitation by about 10 % and a decrease in frequency of wet-days by 1 % between the control (1961-90) climate and the scenario (2041-70) climate. Both daily mean precipitation and frequency of wet-days increase during winter and decrease during summer. The results also indicate an increase in the intensity of the precipitation, especially during winter. A winter increase and summer decrease of the westerly flow seems to be the major cause of the changes.
Department/s
- Dept of Physical Geography and Ecosystem Science
Publishing year
2002
Language
English
Document type
Dissertation
Publisher
Maj-Lena Linderson, Dept. of Physical Geography and Ecosystems Analysis, Lund University, Sölvegatan 13, 223 62 Lund, Sweden,
Topic
- Physical Geography
Keywords
- physical geography
- Geologi
- fysisk geografi
- Geology
- statistical downscaling
- atmospheric circulation
- spatial distribution
- precipitation
- Scania
- Sweden
Status
Published
Supervisor
- [unknown] [unknown]
ISBN/ISSN/Other
- ISBN: 91-973857-5-1
- ISBN: 0346-6787
Defence date
31 May 2002
Defence time
10:00
Defence place
Sölvegatan 13, 3 vån, Lund
Opponent
- Javier Martín-Vide (Prof)