source: cru/metoffice, uk
DESCRIPTION
“Climate change in the Netherlands” Albert.Klein.Tank @ KNMI.nl UGV symposium Global Change, 22 March 2006. Source: CRU/MetOffice, UK. Since 1975, warming dominates in all seasons, except Autumn. Source: Klein Tank, 2004. Source: IPCC, TAR, Chapter 2, 2001. upper 10-ptile 1961-1990 - PowerPoint PPT PresentationTRANSCRIPT
“Climate change in the Netherlands”
Albert.Klein.Tank @ KNMI.nl
UGV symposium Global Change, 22 March 2006
Source: CRU/MetOffice, UK
Since 1975, warming dominates in all seasons, except Autumn
Source: Klein Tank, 2004
Source: IPCC, TAR, Chapter 2, 2001
upper 10-ptile 1961-1990
the year 1996
lower 10-ptile1961-1990
upper 10-ptile 1961-1990
the year 1996
lower 10-ptile1961-1990
“cold nights”
upper 10-ptile 1961-1990
the year 1996
lower 10-ptile1961-1990
“cold nights”
“warm nights”
Station De Bilt (The Netherlands)
warm nights
cold nights
Observed trends (days per decade)for 1951 to 2003
Alexander et al., J.Geophys.Res., 2006
Relation between relative trend bq/X required for 80% detection probability (5% level) and series length Nfor extreme events with average return period Tret
Source: Klein Tank and Können, J. Climate, 2003
21365~ retTXbq
6x
23~ NXbq
3x
Day-count indices of extremes
Geostrophic winds based on pressure triangles; blue circles are 95th and red crosses 99th percentiles (standardized units)
updated from: Alexandersson et al., Climate Res., 2000
Wind study the Netherlands 1962-2002
Smits, Klein Tank, Können, Int.J.Climatol., 2005
Observed trends for 1962-2002
Annual precipitation Netherlands
Precipitation fraction due to very wet days
1) Identify very wet days using a site specific threshold = 95th percentile at wet days in the 1961-90 period
2) Determine fraction of total precipitation in each year that is due to these days
3) Trend analysis in series of fractions
eca.knmi.nl
Groisman et al., 2005
“Amplified” response of very wet days(trends over last 50 yr)
Temperature
Source: IPCC TAR, 2001
Source: IPCC AR4 simulations (partly available at: climexp.knmi.nl)
+5.8°C
+1.4°C
Source: Katsman,
2006
Sea level change globally
Departures in the Eastern North Atlantic
Summer precipitation change inHadley Centre climate model simulations
blue = daily extremes
red = seasonal total precipitation
Source: Selten, Dijkstra, Kliphuis, et al., CLIVAR, 2003
simulation 19simulation 7
CHALLENGE project(62 model-simulations of August rainfall totals
in NL)
KNMI will soon present new climate change scenarios for the Netherlands, which replace the WB21 scenarios from 2000:
29 May 2006
THANKS !
htpp://eca.knmi.nl
http://www.knmi.nl/scenarios
mailto: Albert.Klein.Tank @ KNMI.nl