Local scale examples from Slovenia - wamis.org · Increased variability of water supply More...
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Drought analysis Local scale examples from Slovenia Tjaša Pogačar Agrometeorological Department, EARS
Transcript of Local scale examples from Slovenia - wamis.org · Increased variability of water supply More...
Drought analysis
Local scale examples from SloveniaTjaša PogačarAgrometeorological Department, EARS
Contents
What basic and evaluated data is available for drought analysis (monitoring)?
Who collects the data and where can we get it? Our methodology and tools for drought analysis To whom and where are these data and analysis
information available?
Slovenia a great diversity of:
Precipitation amount
Land use
Soils
Increased variability of water supply
More frequent occurrence of droughts and water surpluses (not only floods)
Important to analyze both extremes
Droughts in 2003, 2006, 2007
Drought and water surplus in 2009
15 June – 15 July 2009
Drought
Water surplus
Government arrangements ‘De minimis’: financial help for farmers
Basicvariables
PRECIPITATION
in comparison to long-term averages
data: Meteorological Office
DROUGHT STRESS
Basic variables
0
5
10
15
20
25
30
Bab
no P
olje
Rat
eče
Pos
tojn
a
Lesc
e
Koč
evje
Brn
ik
Mar
ibor
Cel
je
Por
toro
ž
Ljub
ljana
Mur
ska
Sob
ota
Črn
omel
j
Nov
o m
esto
Bilj
e
num
ber o
f day
s
T over 30°C T over 30°C in RV below 40%
maximum air temperature over 30 °C
and
low relative humidity (14:00)
HEAT STRESS
Fruit damage due to heat stress:
2-3 days of 5h T over 30 °C and
daily global radiation over 2400 J/cm2
data: Meteorological Office
maize: leaf folding
AIR TEMPERATURES
TEMPERATURE THRESHOLDS:
Basic variables
Double effect: 2009
data: Meteorological Office
DROUGHT and HEAT STRESS
POTENTIAL EVAPOTRANSPIRATION
Penman-Monteith:
• tested
• systematically used
• result: improved quality of drought monitoring
Basic variables
Soil water measurements
Soil data: field capacity, wilting point, water holding capacity ...
data: Meteorological Office
soil data: Biotechnical Faculty
SOIL WATER
PROBLEMS
with datasoils
Time Domaine Reflectometers instead of GRAVIMETRIC method
Intensity
of rain
What happens with soil water?
Percolation ... Every rain drop is not usefulso
ilch
arac
teris
tics
Evaluated variables
Basic water balance: RR - ETP (precipitation – potential
evapotranspiration)
prepared data: SAgMIS (Slovene AgroMeteorological Information System)
WATER BALANCE
http://meteo.arso.gov.si/met/sl/agromet/recent/wb/
On-line available only data for 7 stations
DAILY and WEEKLY
cumulative for VEGETATION PERIOD
precipitation, potential evaporation and water balance
PROBLEM
for users
Evaluated variables
Average July 1971-2000 July 2010
WATER BALANCE
IRRFIB: water-balance model
• potential evapotranspiration (Penman-Monteith)
• precipitation
• phenological phases and crop coefficients
• roots depth
• field capacity and wilting point
• actual evapotranspiration
• crop water demands
• soil water content
• soil water deficit
• irrigation demands
Initial
conditions!
Other possibility: WINISAREG model
Model and measurements
goodagreement
r = 0.84
tested for a variety of crops
comparison for 3 years
IRRFIB:crop water deficit and stress days
-300
-250
-200
-150
-100
-50
0
50
100
150
2003
1993
1983
2001
2000
1988
1984
2007
1999
2008
1981
2002
1985
2004
1991
1994
1998
1987
2006
1986
1990
2005
1982
1989
1973
1997
1980
1972
1975
CWD [mm] stress days
Crop water deficit (CWD) and stress days for maize on soil with medium water holding capacity in Murska Sobota in the period 1972-2008 in descending order
difference between precipitation and crop evapotranspiration
days with the soil water content under the limit (50% FC)
+ proxy data
Yield vs. Crop water deficit
Yield vs. crop water deficit (CWD) for maize on soil with medium water holding capacity in Murska Sobota in the period 1983-2008
higher crop water deficit leads to yield decrease
r = 0.65
PROBLEMS
with data
Rain-fed
Irrigation in Slovenia
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
1995 2000 2005 2006 2008
Povr
šina
(ha)
Zemljišča pripravljena za namakanje Namakana zemljišča
area
[ha]
Land prepared for irrigation Irrigated land
• traditional way of farming
• governmental subsidies after droughts
• non-rational water use
SAgMIS: Slovene AgroMeteorologicalInformation System
IRRFIB simulation – non irrigated
water use
deficit
8.3. – 21.4.2010
SALAT (Ptuj)
22.4. – 19.7.2010
MAIZE (Maribor)
recent additional analysis
for specific location, soil and crop
SAgMIS: Slovene AgroMeteorologicalInformation System
IRRFIB simulation – irrigated
1.5. – 1.10.2008: MAIZE (Murska Sobota)sprinkler irrigation
water use
deficit
recent update:
FORECAST of irrigation
project
Data dissemination
Agricultural Advisory Service
E-mail Promotions (conferences) Articles Publications
Internet
VIA:
on-line irrigation forecast
http://meteo.arso.gov.si/met/sl/agromet/
Data dissemination
In the vegetation period
(April – September):
DECADAL BULLETIN
http://meteo.arso.gov.si/met/sl/agromet/recent/wb/currentyear/
DECADAL BULLETIN
page 2
Page 2
Page 3
Page 4
Page 5
Data dissemination
Internet page with up-to-date data
publicationsavailable data (archive)
phenological datalong-term averages: understanding of past
drought occurrencesreal-time data
