Climate Trends in Israel and
Effects on Water Resources
Amir Givati, Israeli Hydrological Service,
Israeli Water Authority
1
Climate and hydrological observations in Israel.
Projected changed and the effect on water
resources.
Cooperation between the Water Authority and
governmental offices and Academic institutions:
Ministry of Environment, Ministry of
Agriculture, Tel Aviv University, Hebrew
University.
2
Tools that are being use
in the Water Authority
Seasonal precipitation models - NCEP / NCAR
Climate models - Tel Aviv University (Prof. P.
Alpert).
Stream flow - IHS, The Lake Kinneret
Limnological Laboratory (Dr. Alon Rimmer)
Aquifers recharge: HUJI (Prof. H. Gvirtzman)
Evaporation / Lake Kinnert salinity - The Lake
Kinneret Limnological Laboratory (Dr. Alon
Rimmer)
3
•
What do we know until now ?
•
What are the forecasts that we
have for the coming decades ?
4
Temperatures:
There is a wide agreement that temperatures increased in Israel
during the last decades, especially in the summer
Increase in summer , no trend at winter
1 degree increase in the summer
Stability in the winter
Ziv et al., J. Roy. Met. Soc. 2010
5
Temperatures
The temperatures in Israel with respect to the Global temperatures
Summer
Winter
Ziv et al., J. Roy. Met. Soc. 2010
6
Precipitation:
No clear trend was found. Several studies showed different trends for different
places (coast, inland, north vs. south, the hilly areas vs. the plain).
Time series for 13 rain gauges with long
record of measurement since 1920
1200
1200
1000
Jerusalem
y = -213.14 + 0.36384x R= 0.073716
y = 514.97 + 0.0062349x R= 0.001
mm/y
mm/y
1000
800
800
600
600
400
400
200
200
0
1920
1900
192019401940
1960
1960
Years
Years
1980
1980
2000 2000
2020
7
Precipitation trends in the major Aquifers in Israel:
Kinnert, Western Galilee, Mountain, Coastal Aquifer
Kinnert
Western Galilee
Mountain
Coast
y = 567.26 - 0.37176x R= 0.06
y = 578.57 + 0.13377x R= 0.02
y = 538.39 + 0.623x R= 0.09
y = 544.11 - 0.19604x R= 0.03
1200
1000
• Slight decrease in
the Kinnert basin
Mountain and coast
800
mm/y
• Stable trend in the Galilee,
600
400
200
1927 1937 1947 1957 1967 1977 1987 1997 2007
years
8
Golan cluster [mm/year]
Decreasing trend at hilly rain gauges, Northern Israel
Cluster of rain gauge in the northern Golan
Ending / Starting = 755 / 869 = 0.87
1600
y = 8340.4 - 3.783x R= 0.15
1400
B
1200
1000
800
600
400
200
0
1975 1980 1985 1990 1995 2000 2005
Year
9
Statistically significant decrease in annual precipitation in the Kinnert basin
PP
− value
: 0.025
− value
: 0.04↓↓
P - value
Rom and Givati, 2009
:0.04 ↓
10
Ratio between annual flow in Dan spring to
precipitation in Jordan valley cluster
1951-2005: Ending / Starting = 0.94 / 1.05 = 0.90
1975-2005: Ending / Starting = 0.91 / 1.05 = 0.86
1.4
B
0.15
1.2
1
0.8
Ratio between outflow of Banias
spring to rainfall in Jordan cluster
Ending / Starting Ro = 0.10 / 0.12 = 0.83
y = 1.478 - 0.0007x R= 0.46 P = 0.02
0.14
y = 4.234 - 0.0016x R= 0.30 P = 0.02
y = 10.212 - 0.0046x R= 0.48 P=0.004
Ro [106m3/mm]
Observed / predicted outflow ratio
Decreasing trend in the major water resources of Israel:
Precipitation and spring flow in the upper Jordan River basin
B
0.13
0.12
0.11
0.1
0.09
0.08
0.6
0.07
1950
1960
1970
1980
1990
2000
1980
1987
1995
2003
Year
year
Givati and Rosenfeld, WRR, 2007
11
Available water volume in lake Kinneret
Ending - Starting = 349 - 492 = -143
6
3
-1
Available Water [10 m year ]
1600
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
1400
A
y = 9588.2 - 4.6057x
486 - 282 = 215 MCM
1200
y = - 5.8102x + 502.51
1000
800
600
400
200
0
1975 1980 1985 1990 1995 2000 2005 2010
Givati and Rosenfeld, WRR, 2007
19
8
19 0/8
8 1
19 1/8
8 2
19 2/8
8 3
19 3/8
8 4
19 4/8
8 5
19 5/8
8 6
19 6/8
8 7
19 7/8
8 8
19 8/8
8 9
19 9/9
9 0
19 0/9
9 1
19 1/9
9 2
19 2/9
9 3
19 3/9
9 4
19 4/9
9 5
19 5/9
9 6
19 6/9
9 7
19 7/9
9 8
19 8/9
9 9
20 9/0
0 0
20 0/0
0 1
20 1/0
0 2
20 2/0
0 3
20 3/0
0 4
20 4/0
0 5
20 5/0
0 6
20 6/0
0 7
20 7/0
20 0 8
09 8/0
/2 9
01
0
Annual volumes [MCM]
Decreasing trend in available water volume into the
Lake of Galilee
12
Using the SPI Drought Index in order to
calculate drought duration and intensity
Jerusalem
1000
500
0
1860
1880
1900
1880
1900
1920
Jerusalem,
Time1940
Scale: 1 Years1960
1980
2000
1980
2000
3
2
1
SPI
mm/year
1500
0
-1
-2
-3
1860
1920
1940
1960
Rom and Givati, 2009
13
Future Projections
Precipitation
Drought index
Incoming water to Lake Kinnert
Evaporation
Recharge in Aquifers
14
Effect of possible climate change scenarios in Israel on droughts
Rom and Givati, 2009
15
Climate Modeling in Israel
Trends of mean seasonal precipitation in (%)
Alpert P., S.O. Krichak, 2009
16
Modeling future available water in Lake Kinnert
Calculated precipitation (A) and (B) evaporation for the period 2015-2034 based on
statistical downscaling (TAU) form Kitoh et. al ,2008 climate model
300
2000
B
Observed precipitation
Modeled precipitation
1500
1000
500
0
1970 1980 1990 2000 2010 2020 2030 2040
Years
Annual Evaporation [mcm]
Annual precipitation [mm / y]
A
280
Modeled evaporation
Observed evaporation
260
240
220
200
1970 1980 1990 2000 2010 2020 2030 2040
Years
Givati et al., 2010. Water Resources Research (in review)
17
Summary of the climate, Hydrological, evaporation and salinity
concentration models and the effect on water availability in Lake Kinnert
2015 –
2034
Modeled
Period
1979 – 2007
Observed
1979 – 2007
Modeled
Future
Change
Future Change
[%]
Average
Precipitation
[mm]
835
832
802
-30
-4%
Std Precipitation
[mm]
271
263
228
-35
-13%
Average Incoming
water [mcm]
663
664
620
-44
-7%
Std
Incoming water
[mcm]
273
256
246
-10
-4%
Average
Evaporation
[mcm]
230
238
249
11
5%
Average Available
water
[mcm]
408
401
345
-56
-14%
Std
Available water
[mcm]
273
272
250
-22
-8%
Average Cl
Concentration
in the lake (mg/l]
233
234
277*
43
18%
18