Date post: | 02-Jan-2016 |
Category: |
Documents |
Upload: | benedict-dawson |
View: | 221 times |
Download: | 0 times |
Summary of observed Summary of observed changes in precipitation and changes in precipitation and
temperature extremes temperature extremes (D9)(D9)
ObjectiveObjective
Are extremes becoming more severe?Are extremes becoming more severe?
Are they becoming more frequent?Are they becoming more frequent?
How is the spatial pattern of the observed How is the spatial pattern of the observed
changes?changes?
Is there seasonal variability in the changes?Is there seasonal variability in the changes?
Method of analysisMethod of analysis
Time series of Time series of Daily precipitation, Daily precipitation,
Daily max/min temperaturesDaily max/min temperatures
Definition of indices that correspond to extremesDefinition of indices that correspond to extremes
Calculation of annual seasonal values of the indicesCalculation of annual seasonal values of the indices
Linear regression applied on the time series of the Linear regression applied on the time series of the
calculated indicescalculated indices
Non-parametric test of significanceNon-parametric test of significance
Study regions and numbers of stations Study regions and numbers of stations investigatedinvestigated
RegionRegion PartnerPartner No. P.statNo. P.stat No. T.statNo. T.stat
EuropeEurope UEAUEA 481481 481481
EnglandEngland UEAUEA 4040 2121
GermanyGermany USTUTT-IWSUSTUTT-IWS 611611 232232
GreeceGreece AUTHAUTH 2222 2222
N. ItalyN. Italy ARPA-SMRARPA-SMR 6262 4444
SwitzerlandSwitzerland ETHETH 104104 NoneNone
French AlpsFrench Alps CNRSCNRS 3+gridded 3+gridded datadata
33
Extreme indices investigatedExtreme indices investigated
DesignationDesignation DescriptionDescription
Precipitation related indicesPrecipitation related indices
Prec90pPrec90p 90th percentile of rainday amounts (mm/day)90th percentile of rainday amounts (mm/day)644R5d644R5d Greatest 5-day total rainfallGreatest 5-day total rainfall646SDII646SDII Simple Daily Intensity (rain per rainday)Simple Daily Intensity (rain per rainday)641CDD641CDD Max no. of consecutive dry daysMax no. of consecutive dry days691R90T691R90T % of total rainfall from events > long-term 90th percentile% of total rainfall from events > long-term 90th percentile692R90N692R90N No. of events > long-term 90th percentile of raindaysNo. of events > long-term 90th percentile of raindays
Temperature related indicesTemperature related indices
Tmax90pTmax90p Tmax 90th percentileTmax 90th percentileTmin10pTmin10p Tmin 10th percentileTmin 10th percentile125Fd125Fd Number of frost days Tmin < 0 °CNumber of frost days Tmin < 0 °C144HWDI144HWDI Heat wave DurationHeat wave Duration
ResultsResultsEuropeEurope
Heavy precipitation extremes:Heavy precipitation extremes:
WinterWinter
Increased in central Europe, the UK and Scandinavia.Increased in central Europe, the UK and Scandinavia. Decreased in Eastern Europe, Greece, and western Iberian Peninsula.Decreased in Eastern Europe, Greece, and western Iberian Peninsula.
SummerSummer
increased across northern Scandinavia and Russiaincreased across northern Scandinavia and Russia decreased across the UK and NE Europedecreased across the UK and NE Europe increased through SW Europeincreased through SW Europe decreased across the northern Iberian Peninsula.decreased across the northern Iberian Peninsula.
Dry day persistenceDry day persistence
WinterWinter
increased in the southern part of the region increased in the southern part of the region decreased in the northdecreased in the north the increase is generally greater than the decreasethe increase is generally greater than the decrease
SummerSummer
Less coherent signalLess coherent signal Most stations in the central part, the UK, and southern Most stations in the central part, the UK, and southern
Scandinavia Scandinavia
showed an increase.showed an increase.
Temperature extremesTemperature extremes
WinterWinter Extreme maximum temperature increased over most of the Extreme maximum temperature increased over most of the
region except the SEregion except the SE
Extreme minimum temperature Extreme minimum temperature increased over the entire increased over the entire region apart from small decreases in parts of Greece, the region apart from small decreases in parts of Greece, the Iberian Peninsula and ScandinaviaIberian Peninsula and Scandinavia
Extreme minimum temperature increased to a larger degree Extreme minimum temperature increased to a larger degree
than the corresponding extreme maximum temperaturethan the corresponding extreme maximum temperature
SummerSummer Extreme maximum temperature incresed in most area of Extreme maximum temperature incresed in most area of
the region except the region except in northern Scandinavia, Eastern Europe, in northern Scandinavia, Eastern Europe, and Russiaand Russia
Extreme minimum temperature increaded in most areas Extreme minimum temperature increaded in most areas except that a few stations showed a decreaseexcept that a few stations showed a decrease
Local scale trends in extreme heavy Local scale trends in extreme heavy precipitation indicesprecipitation indices
RegionRegion WinterWinter SpringSpring SummerSummer AutumnAutumn
EnglandEngland ++++ ----
GermanyGermany ++++ ++ ---- ++
N. ItalyN. Italy -- -- ++ ++
GreeceGreece -- --
SwizerlaSwizerlandnd
++++ ++ ++ ++++
French French AlpsAlps
VariableVariable variablevariable variablevariable ++
Local scale trends in extreme maximum Local scale trends in extreme maximum temperaturetemperature
RegionRegion WinterWinter SpringSpring SummerSummer AutumnAutumn
EnglandEngland ++ ++ ++ ++
GermanyGermany ++ ++ ++
N. ItalyN. Italy ++ ++ ++ ++
GreeceGreece ++ ++ ++ ++
SwizerlaSwizerlandnd
------------ ------------ ------------ ------------
French French AlpsAlps
++ ++ ++++
Precipitation trends / FloodsPrecipitation trends / Floods
Areal precipitation vs. Point Areal precipitation vs. Point precipitationprecipitation
Simultaneous occurrence of extremesSimultaneous occurrence of extremes Differences between trends Differences between trends
corresponding to nearby stationscorresponding to nearby stations Trend Trend Interpolation or Interpolation or
InterpolationInterpolation Trend Trend
Trends in the areal precipitation indicesTrends in the areal precipitation indices
Point scale Grid size of 10km x10km
Winter trends in the 5 day total rainfall amount
#S
S
S
#SS#S
SSSSS
#SS
#S#S#S#SS
S#S#S#SS
#S#S#SS
#S#SSS
S#S
S
S#S
SS
#SS
#SS #S#S#S#S
S
#SS#S#S#S
S TS
#S#S
S
S SSSS#S
SSS
S
S
#S #S#S
SSS
#SS#S#S#S#S
#S#S
#S
S
S#SS#S#SS#S#S S
SS
#S #S#S
S
SS
S
S
SSS
S S
SSSS
S
S
SS
S
SSS
#SS
TS
SS
S
SS
S
S
SSS
SS
S
SS
#SSSSSS
S
#S
S
S
S
SS
S
S
S
S#S SSS
S
S
S
S
#S
SS
SS
S S
S
#S
SS
S
SS
S
S
S
SSSSS
#S
S#SS
S#S#S
#SSS
S
S
S
S
S
SS
SS
S
SS
#S
S
S
S
SSS
SS
#S
S
SS S
S
#S#SS
SSS
S
SSS
SS
S
S
S
S
SS
SS
S
S
S
S
S
SSSS
SSS
T
SSSSSS
ST
SS
SSSS
SS
SSS
S SSS
S
SS
S SS
SSS
S
SSSS
T
S#S#SSSS
SS
S
S
SS S
SSSSSS
SSSSSS
SSS
SS
SSSSS
S
#ST
SSSS
S T
SS
T
SS
S
SS
S
SSSSSS
S
SS
S
SS
S#S
SS
S
#S
S
S
SS
SSSSSS
SSSS
SS
SS
SSS
SS
SSSS
SS
T
SSSSSSSSS#S
S
SS#SS
#SS
S
SSS SS#S
S
SSS
SS
SS
S#SS
S
#SSSSSSS
S
SS#SS
SS
S
S
SSSS
#S
#S
S
#SSS#SS
SS#S
S
#S#S#SSS
SSS
SS
SS
SSSS
SSS
#S S
#S#S
#SS#S
SS#S
S#S
#S#S#SSS#S#S SS
#SSSS
SS
SS
SS
#S#S#S#SSS S
SST SSS
SSSS
SSSSSSS
SSS
S
#S
S
SS
S
S SS#S
#SS#S
S#SSSS#S#SSS#S#S#S S
S
ST
STSS
S#SS
SS
#SSSS#S#SS
SS
SS#SSSSSSS#SSSSS#SSSSSSS#S#S
T - 0 . 6 - - 0 . 3T - 0 . 3 - 0S 0 - 0 . 3S 0 . 3 - 0 . 6S 0 . 6 - 0 . 9S 0 . 9 - 1 . 8
%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% %%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%
%%%%%%% %%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%
%%%%%%%%%%%%%%%%%%%%%% %%% %%%%%%%%%%%%%%%%%%%%% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %%%%% %%%%%% %%%
%
<-0.3 -0.3 – 0.0 0.0 – 0.3 0.3 – 0.6 0.6 – 0.9 >0.9
SummarySummary
There are significant trends in the There are significant trends in the extreme indicesextreme indices
Variability increases Variability increases (Ex.: dry day duration and 5 day (Ex.: dry day duration and 5 day sums both increase)sums both increase)
Trends in downscaled seriesTrends in downscaled series