Title: Understanding what Water Deficits and Climate Variability Mean to Viticulture and Wine Production
1Understanding what Water Deficits and Climate
Variability Mean to Viticulture and Wine
Production
2Talk Outline
- Viticulture/Wine System
- Grapes, Wine, and Climate
- Water Requirements
- Climate Variability
- Overview and Conclusions
3Viticulture/Wine System Overview
- Weather/Climate
- Mild winters, low freeze/frost risk
- Stable, cloud-free conditions during bloom
- Warm and dry summers
- Dry maturation period with moderate to high DTR
- Water
- Low water need compared to other crops
- Overall need or amount depends on location
- If irrigated, mostly drip very efficient
- Greatest need in initial development (years 1-5)
- Deficit irrigation practiced once mature
- Some frost protection use
- Old World vs New World issues
4Phenological Calendar with Weather/Climate/Water
Issues
5- Quality Wine Production results from the balance
of four ripeness clocks running simultaneously
but at different rates - Sugar accumulation
- Acid respiration
- Phenolic ripeness
- Fruit character
Fruit character goes from vegetal, herbal,
fruity, jammy to cooked.
6- Water/Irrigation needs in any particular location
in any particular year are controlled by - Spatial variations in climate
- Year-to-year variations in weather
- Soil type
- Topography
- Management (variety/clone, rootstock, spacing,
cover-cropping, etc)
7- Water Deficit Issues
- Smaller canopy
- Fewer and smaller clusters
- Smaller grapes
- Increased competition (ground cover, natives,
between plants) - Soil salinity imbalances over the long term
8- Water Deficit Issues
- Non-irrigated vines Quality ? ? Yield ? ?
- Irrigated vines Quality ? ? Yields
maintained - However, if combined with high temperatures
- increased plant stress/water demand and Quality
? ? Yield ? ?
9Varietal-Climate Thresholds
Plasticity Adaptation Management
(short-term) Varietal (long-term)
Optimum Zone Consistent sugar levels, Ripe
flavors, Generally balanced - Vintage variations
driven by seasonal climate factors (frost,
untimely rain, etc.)
Wine Production and Quality Metrics
Yield/Production Balanced Composition Typical
Varietal Flavors Vintage Ratings/Price
Climate Metrics Growing Season Average
Temperatures, Heat Accumulation
10- Climate influences the style of wine an area
can produce - Each variety is generally grown in specific
regions and narrow climatic zones for optimum
quality and production
11Global Viticulture Zones
1950
National Center for Atmospheric Researchs
Community Climate System Model (CCSM) A1B
(mid-range scenario) 1.4 x 1.4 Lat/Lon
Jones (2007) in preparation
12Global Viticulture Zones
1999
National Center for Atmospheric Researchs
Community Climate System Model (CCSM) A1B
(mid-range scenario) 1.4 x 1.4 Lat/Lon
Isotherms shift poleward 80-240 km (from
1950) Some expansion NH, mostly declines SH
Jones (2007) in preparation
13Temporal Spatial Variability in Growing
Degree-Days
Jones, White, and Myers 2007
141948-2004 15 Parameters 46 Climate
Stations Aggregated to 11 Regions Puget
Sound Columbia Valley, WA Columbia Valley,
OR Willamette Valley Umpqua Valley Rogue
Valley North Valley Foothills North Coast Central
Coast Central Valley
15Growing Season Growing Degree-Days
326 Mean 94 Stdev
16Median Date of Last Spring Frost (0C)
-24 Mean 12 Stdev
North Coast
17Napa Valley Cabernet Sauvignon Vintage
Ratings (Wine Spectator)
18Napa Valley Cabernet Sauvignon Release Price vs
Vintage Ratings
Rating effects on price are exponential, with a
10-point increase from 80 to 90 resulting in a
200 price increase and an increase from 85-95
resulting in a 350 price increase
19PDO-ENSO Modulation Effects on West Coast U.S.
Wine Regions and Wine Quality in Napa Valley
20(No Transcript)
21Ratings and Teleconnections 1933-2002
Of the 7 worst years (ratings lt71), 6 are neutral
ENSO-cold PDO
22What about 1999-2002 and Beyond?
- PDO has displayed more inter-annual variability
since 1998 - Ratings 5-year moving average appears headed
down since 1997 - 1998, 2000, and 2002 all much lower than 5-year
moving average
The 2005 and 2006 vintages have not been rated
yet Climate structures during these years would
point to highly rated vintages (gt90) Early
indications are for good wine quality, with 2005
a record for production
23Oregon Regional Irrigation Climatology for
Winegrapes
Salem
1996
1996
1983
1998
1999
1983
Jan-Jun Rainfall Anomaly (in)
1985
1973
2001
1985
1977
2001
Medford
Pendleton
1995
1998
1956
2000
1978
1996
1992
1964
1973
2001
1994
1985
24Simulated Soil Moisture and Cumulative Irrigation
Rogue Valley 1999 dry/warm 2000 typical
2005 wet/cool
Medford Agrimet, Ruch Gravelly Silt Loam
Statewide Annual Variation in Irrigation Needs
(1989-2006) Range of Replenishment Needed - 2.5
to 12.8 inches Dry/warm years 13-71 increase,
5-24 days earlier Wet/cool years 14-30
decrease, 11-22 days later
25Overview and Conclusions
- The viticulture/wine production system is a
unique specialty crop with strong value added
components driven by a wide range of varieties. - Wine production is a climatically sensitive
endeavor, with narrow zones providing the most
optimum production and quality characteristics,
which therefore puts the industry at great risk
from both short term climate variations and long
term change. - Desirably low summer/fall rainfall, low water
requirements compared to other crops, and
efficient irrigation methods make wine
production more suited to regions prone to
drought. - Some controlled water deficit is good for
quality, however long term drought can bring
about smaller yields and soil salinity
imbalances.
26(No Transcript)
2770
Eastern Oregon and Washington Extreme Freeze
Frequencies
of Days
lt
20
F
60
of Days
lt
5
F
Moving Average
50
40
Count
30
20
10
0
1927
1942
1957
1972
1987
2002
Winter (Oct-Mar)
28Eastern Oregon and Washington Extreme Minimum
Temperatures