Methodologies for climate variability analysis of winegrowing regions.
A case study of Bordeaux winegrowing area.
Benjamin BOISCentre de Recherches de Climatologie
Université de Bourgogne
Spatial analysis of climatefor viticulture
• Risk management– Pest management (models)– Frost, hail, wind, excessive drought risks
• Terroir comprehension and characterization– Vineyard management– Site selection
Source : RSVAH (2007), Sandoz
Bindi & Maselli (2001)
1 cm 10 cm 1 m 10 m 100 m 1 km 10 km 100 km 1000 km
Micro-scale
Macro-scale
Leaf Canopy Plot Vineyard
Climate differences > Uncertainty From Oke (1978)
Climate differences Uncertainty ?
Local scale
Meso-scale
Spatial scale in climatology
Region Country
Climate spatialization
11,5°C
12°C
14°C13°C
?
Interpolation
Meteorological models
Remotesensing
Bordeaux winegrowing region
Normals (1976-2005)Villenave d’Ornon
0
5
10
15
20
25
30
Jan.
Mar
.
Mai
Jul.
Sep
t.
Nov
.
Tem
pera
ture
(°C
)0
20
40
60
80
100
120
Rai
nfal
l (m
m)
RRTminTmaxTmoy
Rainfall
ET0
Rs
MODELS ETAGRO-
CLIMATICINDICES
at daily time step
Soil water balance
Degree-days
Stat
ions
TminTmax
Rad
arC
OR
INE
DEM
Sat Zoning
Zoning relevance
• Is the spatialization uncertainty sufficiently low to draw reliable analysis of the spatial structure of climate ?
Spatialization accuracy
Variable Spatialization technique
Available period
Evaluation period
RMSE (Apr.-Sept.)
Rainfall Ordinary kriging 1994-2005 1994-2005 5.6 mm/month(11%)
Tmin
Multiple regression +
kriging2001-2005 2001-2005 0.86°C
Tmax
Multiple regression +
kriging2001-2005 2001-2005 0.6°C
RsSatellite sensing
+ DEM 1985-2005 2001-2005 3.3 MJ/m²/day(17%)
ET0 Turc method 2001-2005 2001-2005 0.57 mm/day (16%)
Spatialization accuracy
TEMPERATUREHalf-véraison
(DD prediction vs. field observations)
Predicted values vs. grapevine phenology
Spatialization residuals (errors) vs. Measured spatial variability
RAINFALLComparison of several interpolation
methods
Zoning relevance
• Is the spatialization uncertainty sufficiently low to draw reliable analysis of the spatial structure of climate ?
• Is the spatial structure redundant ?
Rainfall year-to-year variability
20041994
64%21%
12%1%1%
1%
Degree.days Zoning2001-2005 period
Cool zones ( +5 to +15 days): Early cultivars
(Merlot, white cultivars,…)
Warm zones ( -5 to -15 days): Late cultivars
(Cabernet-Sauvignon, Petit Verdot)Climate change consideration
Interclass interval : 42 to 79 DD 5 to 11 days
Conclusions
• New technologies (remote sensing, GIS, increasing computing potentialities)More accurate interpolations, reduction of the
“cost / scale dilemma”
Conclusions
• The need for climate spatial analysis recommendations Numerous methods and data
Ergonomic ≠ simple !
Thanks !
…Work in progress…
TERVICLIM(Very large scale climate analysis and modelling)
Large scale climate analysis(Jones et al.)
World classification of winegrowing
regions
Bois (unpublished)
Résultats
RMSE = 0.86°C RMSE = 0.59°C
Temperature2001-2005 period Strong inter-annual variations
ST Jan.-Sept. 2002 (DD) ST Jan.-Sept. 2003 (DD)
0.5
0.6
0.7
0.8
0.9
1
Year Apr. -Sept.
RM
SE (°
C) OK
IDWA
MRK
Tmin
Daily temperature spatialization
0.5
0.6
0.7
0.8
0.9
1
Year Apr. -Sept.
RM
SE (°
C)
Tmax
Minimal temperature vs. distance to Gironde estuary
0.00
0.20
0.40
0.60
0.80
1.00
1.20
Année Avr. -Sept.
HYDRAM
Ordinary Kriging
Inverse distance
Multiple regression
0.00
0.20
0.40
0.60
0.80
1.00
1.20
Année Avr. -Sept.
HYDRAM
Ordinary Kriging
Inverse distance
Multiple regression
Rayonnement global• RMSE annuelle de 2,7
MJ.m-2 par jour (19,8%)• Sous-estimation : biais de
-11,1%• Climatologie de la
Gironde– Gradient Ouest-Est de
temps clair décroissant.– Jusqu’à 20% d’écart max.
en hiver, 16% en été (8% en Gironde viticole)
– Effet notable du relief
N
R2 = 0.9289
0
5
10
15
20
25
30
35
0 5 10 15 20 25 30 35
Rs H
elio
Clim
-1 (M
J.m
-2)
Rs pyranometer (MJ.m-2)
Solar radiation spatilization
2001-2005 (1826 days)
Annual RMSE = 2.7 MJ.m-2 (19.8%)RMSE Aug.-Sept. =2.9 MJ.m-2 (16.6%)
10 to 6%6 to 1%3 to -3%-3 to -8%-8 to -13%Urban areas
Saint-Émilion village
ET0
Rs
TminTmax
Potential Evapotranspiration : Turc Method with local re-adjustement
Annual RMSE = 0.51 (21%)Apr.-Sept. RMSE= 0.57 (15.9%)
Saint-emilion – “zoom” – moy. Ver mat 20 ans
N
ETP
RMSE = 0.25 mm (11%) RMSE = 0.41 mm (17%)
ETP (prop. Interpolation T)
• Données de validation croisée du processus d’interpolation des températures (MRK)
• Faible propagation des erreurs d’interpolation de la température quotidienne
RMSE ~ 0.05 mm
Radar (Hydram Method)RMSE = 4.4 mm
Ordinary krigingRMSE = 2.5 mm
RADAR
Rainfall spatialization
• Numerous artifacts with radar rainfall estimates
Ordinary kriging at different time steps
114 days – 51 raingauges location