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Performance of the Rossby Centre regional atmospheric model in Southern Sweden: comparison of simulated and observed precipitation

Achberger, C; Linderson, Maj-Lena LU and Chen, D (2003) In Theoretical and Applied Climatology 76(3-4). p.219-234
Abstract
Two climate model simulations made with the Rossby Centre regional Atmospheric model version I (RCA1) are evaluated for the precipitation climate in Scania, southern-most Sweden. These simulations are driven by the HadCM2 and the ECHAM4/OPYC3 global circulation models (GCMs) for 10 years. Output from the global and the regional simulations are compared with an observational data set, constructed from a dense precipitation gauge network in Scania. Area-averaged time series corresponding to the size and location of the RCA1 grid points in Scania have been created (the Scanian Data Set). This data set was compared to a commonly used gridded surface climatology provided by the Climatic Research Unit (CRU). Relatively large differences were... (More)
Two climate model simulations made with the Rossby Centre regional Atmospheric model version I (RCA1) are evaluated for the precipitation climate in Scania, southern-most Sweden. These simulations are driven by the HadCM2 and the ECHAM4/OPYC3 global circulation models (GCMs) for 10 years. Output from the global and the regional simulations are compared with an observational data set, constructed from a dense precipitation gauge network in Scania. Area-averaged time series corresponding to the size and location of the RCA1 grid points in Scania have been created (the Scanian Data Set). This data set was compared to a commonly used gridded surface climatology provided by the Climatic Research Unit (CRU). Relatively large differences were found, mainly due to the fact that the CRU-climatology uses fewer stations and lacks a correction for rain-gauge under-catch. This underlines the importance of the data set chosen for model evaluations. The validation is carried out at a large scale including the whole area of Scania and at the finest resolution of RCA1 (the grid point level). When integrated over the whole area of Scania, RCA1 improves the shape of the annual precipitation cycle and the inter-annual variability compared to output from the GCMs. The RCA1 control climate is generally too wet compared to the observations. At the grid point level, RCA1 improves the simulation of the variability compared to the GCMs. There is a strong positive correlation between precipitation and altitude in all seasons in the observations. This relationship is, however, much weaker and even reversed in the RCA1 simulations. Analysis of the dense rain gauge network reveals features of spatial variability at around 20-35 km in the area and indicates that a finer resolution is needed if the spatial variability in the area is to be better captured by RCA1. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Theoretical and Applied Climatology
volume
76
issue
3-4
pages
219 - 234
publisher
Springer
external identifiers
  • wos:000187604000007
  • scopus:0345765512
ISSN
1434-4483
DOI
10.1007/s00704-003-0015-6
language
English
LU publication?
yes
id
59392b2b-39c9-4dbb-a0de-5d328b90ad26 (old id 291267)
date added to LUP
2007-08-21 11:16:59
date last changed
2018-08-19 03:59:39
@article{59392b2b-39c9-4dbb-a0de-5d328b90ad26,
  abstract     = {Two climate model simulations made with the Rossby Centre regional Atmospheric model version I (RCA1) are evaluated for the precipitation climate in Scania, southern-most Sweden. These simulations are driven by the HadCM2 and the ECHAM4/OPYC3 global circulation models (GCMs) for 10 years. Output from the global and the regional simulations are compared with an observational data set, constructed from a dense precipitation gauge network in Scania. Area-averaged time series corresponding to the size and location of the RCA1 grid points in Scania have been created (the Scanian Data Set). This data set was compared to a commonly used gridded surface climatology provided by the Climatic Research Unit (CRU). Relatively large differences were found, mainly due to the fact that the CRU-climatology uses fewer stations and lacks a correction for rain-gauge under-catch. This underlines the importance of the data set chosen for model evaluations. The validation is carried out at a large scale including the whole area of Scania and at the finest resolution of RCA1 (the grid point level). When integrated over the whole area of Scania, RCA1 improves the shape of the annual precipitation cycle and the inter-annual variability compared to output from the GCMs. The RCA1 control climate is generally too wet compared to the observations. At the grid point level, RCA1 improves the simulation of the variability compared to the GCMs. There is a strong positive correlation between precipitation and altitude in all seasons in the observations. This relationship is, however, much weaker and even reversed in the RCA1 simulations. Analysis of the dense rain gauge network reveals features of spatial variability at around 20-35 km in the area and indicates that a finer resolution is needed if the spatial variability in the area is to be better captured by RCA1.},
  author       = {Achberger, C and Linderson, Maj-Lena and Chen, D},
  issn         = {1434-4483},
  language     = {eng},
  number       = {3-4},
  pages        = {219--234},
  publisher    = {Springer},
  series       = {Theoretical and Applied Climatology},
  title        = {Performance of the Rossby Centre regional atmospheric model in Southern Sweden: comparison of simulated and observed precipitation},
  url          = {http://dx.doi.org/10.1007/s00704-003-0015-6},
  volume       = {76},
  year         = {2003},
}