Post on 15-Apr-2017
transcript
Drought and soil moisture in context of
climate change : results and
operational applications of ClimSec
project in France
Patrick Josse1, Jean-Michel Soubeyroux1,
Eric Martin2, Jean-Philippe Vidal1,3
1 : Météo-France, Direction de la Climatologie et des Services Climatiques
2 : CNRM/GAME, Météo-France/CNRS
3 : IRSTEA, Lyon
Our Common Future Under Climate Change
International Scientific Conference 7-10 JULY
2015 Paris, France
Contents
ClimSec project
Overview of drought patterns
– Drought indices
– Propagation through the hydrological cycle
– Events analysis
Evolution with climate change
– Current trends
– Droughts evolution in future climates
From science knowledge to climate services
– DRIAS web site
ClimSec project
3-year project: “Impact of climate change on drought and soil moisture in France” , funded by Fondation MAIF
Motivated by damages following 2003 drought and the question
whether such events will be more frequent in the future
Focus on the reanalysis of drought events for characterizing present
climate and climatic projections for future evolutions
Operational application on water resources monitoring and drought
anticipation
Vidal et al (2010), Multilevel and multiscale drought reanalysis over France with the Safran-Isba-Modcou hydrometeorological suite.
Hydrology and Earth System Sciences, 14(3), 459-478. DOI : 10.5194/hess-14-459-2010 WMO Norbert Gerbier Price 2010
Safran-Isba-Modcou (SIM)
Safran
atmospheric
analysis system
Optimal Interpolation
of ERA-40 + ground
observations
Gridded rainfall, snowfall,
temperature, humidity, wind speed,
visible, infrared radiation (8km, hourly)
Isba
land surface
scheme
Computation of water
and energy budgets
with soil and
vegetation databases (ECOCLIMAP)
Evapotranspiration, soil moisture,
snow cover, drainage, runoff, etc. (8km,
5 min)
Drainage and runoff
Modcou
hydrogeological
model
Flow routing,
multilayer aquifers
Flow (3-hourly) and water table levels
(1-8km)
wiltfc
wilt
ww
wwSWI
– w : water content
– wwilt : wilting point
– wfc : field capacity
50-year SIM
hydrometeorological reanalysis
(From 1958 to 2008)
Drought indices
Drought : abnormal water deficit in one (or more) part of the land
surface hydrological cycle
Choice of relevant drought indices depends on the socio-economic
activity domain No universal drought index
SIM: consistent computation of variables within the hydrological cycle
Standardized index approach
– Standardized Precipitation Index (SPI) → 8km grid
– Standardized Soil Wetness Index (SSWI) → 8km grid
– Standardized Flow Index (SFI) → >900 hydrometric stations
Variable Drought type
Safran Precipitation Meteorological
Isba Soil Wetness Index Agricultural
Modcou River flow Hydrological
Overview of dry periods
Area affected by drought (% of France area), 3-month indices, threshold 5%
Autumn 1978 1976 1989-1990 2003
SPI3
SSWI3
SFI3
SP
I3
020
40
60
80
100
SS
WI3
020
40
60
80
100
020
40
60
80
100
SF
I3
1960 1970 1980 1990 2000
From indices to events – Local scale
Grid cell located near Toulouse (south-west), SSWI3
-2.0
-1.0
0.0
0.5
1.0
1.5
SS
WI3
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
Duration
Severity
Magnitude
Threshold
P = 5%
Starting date
Peak date
End date
Drought events analysis
Mean
duration
(months)
SPI3 SSWI3
Mean area (% of France)
National event identification according to drought pattern in both space and
time : event envelop, spatial and temporal contiguity
Spatio-temporal characteristics
1. [Duration, severity, magnitude] combined with area
Observed trends on agricultural droughts
Monitoring of mean annual drought area in France as climate change index
Mea
n a
rea (
% o
f F
ran
ce)
Drought mean annual area
with SSWI (1 month) index
1961-1990 mean decadal mean
8 of the last 10 years with drought area
above the 1961-1990 mean Increase of drought area since
1990th
Drought evolutions with climate change
Mean area (%
of France)
A good confidence for a strong increase of agricultural drought along the
21st century
Vidal et al.(2012), Evolution of spatio-temporal drought characteristics: validation, projections and effect of adaptation scenarios.
Hydrology and Earth System Sciences Discussions, 9(2), 1619-1670. DOI : 10.5194/hessd-9-1619-2012
Climate services on Drias website
Drias Web site aims to
provide regionalized
climate projections
computed by several
French laboratories
involved in climate
modeling (IPSL,
CERFACS, CNRM-
GAME).
An appropriation in
three steps : Education
Space, Discover Space
and Products Space
Availability of ClimSec
projections to help
adaptation on water
resources domain
A consistent approach by hydrometeorology modeling for monitoring
drought and characterization of drought events in France
All spatial and temporal characteristics of drought events are
expected to dramatically increase over the century, with stronger
changes for agricultural droughts, already visible on trends.
Development of climate services for water resources to help
adaptation policies
Conclusions
Thank you for your attention
Contact:
Patrick.josse@meteo.fr
1988-1990 SSWI3 drought (envelop P=20%)