Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral...
-
date post
19-Dec-2015 -
Category
Documents
-
view
214 -
download
0
Transcript of Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral...
![Page 1: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/1.jpg)
Space-time trends in temperature extremes
in south centralSweden
Peter Guttorp
Norsk Regnesentral
University of Washington
![Page 2: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/2.jpg)
Acknowledgements
Joint work with Peter Craigmile, The Ohio State University
Data from Swedish Meteorological and Hydrological Institute
Partial support from National Science Foundation
![Page 3: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/3.jpg)
Outline
Data analysis
Marginal fits
Spatial model
Model assessment
![Page 4: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/4.jpg)
IPCC model results (AR4 WG1 Ch.11)
Fewer frost days VL (consistent across model projections)
Decrease in number of days with below-freezing temperatures everywhere
Fewer cold outbreaks; fewer, shorter, less intense cold spells / cold extremes in winter VL (consistent across model projections) Northern Europe, South Asia, East Asia
L (consistent with warmer mean temperatures) Most other regions
Reduced diurnal temperature range L (consistent across model projections)
Over most continental regions, night temperatures increase faster than day temperatures
![Page 5: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/5.jpg)
Data set
Synoptic stations in south central Sweden with 48 years of data
![Page 6: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/6.jpg)
Annual minimum temperatures and
rough trends
![Page 7: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/7.jpg)
GEV model
F(x) exp 1 x
1/
![Page 8: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/8.jpg)
GEV fits
Running estimate of 29 years for Sveg
Suggests linear fit for
![Page 9: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/9.jpg)
Location trends
![Page 10: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/10.jpg)
Location slope vs latitude
![Page 11: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/11.jpg)
Dependence between stations
Sveg Malung Karlstad
Sundsvall 19 12 13
Sveg 25 11
Malung 10
Common coldest day in 48 years5 common to all 4 northern stations
![Page 12: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/12.jpg)
Spatial model
where
Allows borrowing estimation strength from other sites
Can include more sites in analysis
Mt (s) ~ GEV( t (s),,)
t (s) 0 (s) 1(s) t 1961 / 50
i (s) ~ GP( i, i (1 exp( id(s)), i 1,2
![Page 13: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/13.jpg)
Full network
![Page 14: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/14.jpg)
Trend estimates
Posterior probability of slope ≤ 0 is very small everywhere
![Page 15: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/15.jpg)
Spatial structure of parameters
![Page 16: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/16.jpg)
Location slope vs latitude
![Page 17: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/17.jpg)
Prediction Borlänge
![Page 18: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/18.jpg)
![Page 19: Space-time trends in temperature extremes in south central Sweden Peter Guttorp Norsk Regnesentral University of Washington.](https://reader035.fdocuments.in/reader035/viewer/2022062714/56649d2c5503460f94a02395/html5/thumbnails/19.jpg)