AM”I, Tel-Aviv, 22 March 2011

סימולציות אקלימיות של שינויים במאזן המים מעל אגן הים התיכון עם מבט

לישראל – האם אנו מתייבשים?

פינחס אלפרט

ביה"ס פורטר לסביבה והחוג לגיאופיסיקה,

אוניברסיטת תל אביב

בשיתוף עם:ג'ין פנגג'ון, שמעון קריצ'ק, רנה סמואלס, יצחק כרמונה,מעין הראל

Overview

• Factor Separation and synergy- New Book

• Super High-Resolution MRI 20-km climate model- new results

• High Resolution Climate Modeling over the Mediterranean

• High Resolution Model Ensemble over the E. Mediterranean

• Conclusions

PublishedFeb. 2011Cambridge Univ.

Press

One comment on the importance of a proper Factor Separation;

from the Book’s Introduction

“There seems to be some basic psychological tendency in human thinking to present results linearly, with the hidden assumption that the synergies are small or can be ignored.

Nonlinearities in the atmosphere, however, are often significant, and therefore need to be calculated and separated from the pure contributions of each factor, as shown in many very different applications presented in this Book.”

High Resolution Model Ensemble over the E. Mediterranean

• 4 climate models (18-25 km horizontal resolution)

– Japanese MRI 20km– ECHAM- RegCM- 25 km– ECHAM- MM5- 18 km– HADLEY-MM5- 18 km

– First, some results from the Super High-Resolution MRI 20-km climate model:

A. Kitoh, A. Yatagai and P. Alpert, "First super-high-resolution model projection that the ancient “Fertile Crescent” will disappear in this century", Hydrolo. Res. Lett., 2, 1-4, DOI: 10.3178/HRL.2.1, 2008.

Annual Precipitation (mm/year)

CRU

EMclimIPCC AR4 models

20-km model

Total seasonal (Oct-Apr) average precipitation for 1979-2002

The six stations are from south-to-north, Egypt---Cairo (Ca,); Israel---Beer-Sheva (Bs), Tel-Aviv (Ta), Haifa (Hf); Lebanon---Beirut (Be) and Turkey---Adana (Ad). Unit: mm/season.

Comparison of average total observed seasonal P

P E

West inflowWest outflow

S-InF S-OutF

E-InF

E-OutF

N-InF N-OutF

Sketch map

P Categories12345

Amount P P<11=<P<1.51.5=<P<22=<P<2.5 P<=2.5

Unit: mm/day

Water vapor budget equation

A

IF

A

OFdpdlqvdp

g

T

S n

T

S

Q1

A

IF

A

OFPE

Using Green’s Theorem

PEdpg

dpg

qdptg C

T

S

T

S

T

S

QQ111

dPW Vertical integrated moisture flux (VIMF)

VICLFCL=cloud Liquid

By neglect dPW, VICLF +

Area

Total boundary outflow and

inflow

Difference of seasonal total E, P and P-E between the future (2075-2099) and current (1979-2002) 20 km GCM runs. Dashed contour lines indicate the negative changes, i.e. reduction in the future. Unit: mm/season

Annual anomaly of P(black bar) and E (shaded bar) for the future (2075-2099), separated by sea and land area over the Mediterranean region. Calculated by individual year of the future minus the current mean (1979-2007). Unit: mm/day.

Annual P,E changes during 2075-2099 compared to current mean

E

P

Precipitation

categories

CurrentFuture

monthspercentageAver_PmonthspercentageAver_P

P<175%0.901913%0.75

1.5<p>=14124%1.293323%1.26

2<p>=1.55432%1.766142%1.72

2.5<p>=24627%2.242316%2.17

P>=2.52012%2.7286%2.75

Sum168

)28 y(100%1.85

)Mean P(

144)24 y(

100%1.62)Mean P(

Five precipitation categories based on monthly averages in (mm/d) over the whole Mediterranean- current & future

Relationships among the moisture budget components based on the 5 different precipitation categories

ΔP

Unit: mm/day

Current (1979-2007)

Future (2075-2099) minus current

Tinf Tout P E E-P Tout-Tinf

Inflow Outflow

W E N SW

E

N

S

W E N SW E N

S

Comparison of monthly mean precipitation from observed rain gauge (black column) and 20km GCM (grey column) for selected six stations in Israel based on their locations. Unit: mm/day. The selected stations are: Northern Israel---(a) Har-Knaan, (b) Eilon; Center Israel---(c) Tel-Aviv, (d) Jerusalem; Southern Israel---(e) Beer-Sheva, (f) Elat.

Har-Knaan

Tel-Aviv

Beer-Sheva

Streamflow 20km present MRI SST

MIROC SST

in (m3/s)2081-2100 changes

Changes of monthly mean river discharge of six rivers by (1979-2003) compare to (2075-2099). Except to the Jordan River, all rivers flow into the Mediterranean (m3/s). Bold lines ( ) are for current climate, while dashed ( ) for the future.

Early RCM Transient Run A1B 1960-2060

50 km

P. Alpert, S.O. Krichak, H. Shafir , D. Haim, and I. Osetinsky, "Climatic trends to extremes employing regional modeling and statistical interpretation over the E. Mediterranean", Global and Planetary Change, 63, 163-170, 2008.

Annual Precipitation (mm)

0

200

400

600

800

1000

1200

1400

1600

1975

1978

1981

1984

1987

1990

1993

1996

1999

2002

2005

2008

2011

2014

2017

2020

2023

2026

2029

2032

2035

2038

2041

2044

2047

2050

2053

2056

2059

mm

RCMEin Ziw anMaayan Baruch

-~30%

7-day dry spells

0

2

4

6

8

10

12

14

16

18

20

1975

1978

1981

1984

1987

1990

1993

1996

1999

2002

2005

2008

2011

2014

2017

2020

2023

2026

2029

2032

2035

2038

2041

2044

2047

2050

2053

2056

2059

tim

es

RCMEin Ziw anMaayan Baruch

3-day wet spells

0

2

4

6

8

10

12

14

16

18

20

1975

1978

1981

1984

1987

1990

1993

1996

1999

2002

2005

2008

2011

2014

2017

2020

2023

2026

2029

2032

2035

2038

2041

2044

2047

2050

2053

2056

2059

tim

es

RCMEin Ziw anMaayan Baruch

First High Resolution Climate Model Ensemble over the E. Mediterranean

• 4 climate models (18-25 km horizontal resolution)

– Japanese MRI 20km– ECHAM- RegCM- 25 km– ECHAM- MM5- 18 km– HADLEY-MM5- 18 km

• SRES A1B scenario• Weighted ensemble based on Jensen-Shannon

Divergence metric– The models with higher similarity to observations over

a control period are given higher weights

Example: Kfar Giladi-Example: Kfar Giladi- Total Annual Rainfall in mm/y – Total Annual Rainfall in mm/y –

Two past periods (1965-94; 1970-99)Two past periods (1965-94; 1970-99)

Probability Density Function for Kfar Giladi for observed data (2 time periods :

1965-1994) solid ,(1970-1999 (dashed), and 4 models .

p

mm/y

OBS

Example: Kfar Giladi-Example: Kfar Giladi- Number of Wet Days per season Number of Wet Days per season

Two past periods (1965-94; 1970-99) Two past periods (1965-94; 1970-99)

Probability Density Function for Kfar Giladi for observed data (2 time periods :

1965-1994) solid ,(1970-1999 (dashed)), and 4 models. Wet Days shown.

p

Number of Days

Example: Kfar Giladi-Example: Kfar Giladi- Number of 3 Day Wet Spells Number of 3 Day Wet Spells

Two past periods (1965-94; 1970-99) Two past periods (1965-94; 1970-99)

Probability Density Function for Kfar Giladi for observed data (2 time periods :

1965-1994) solid ,(1970-1999 (dashed)), and 4 models. Wet Spells shown.

p

Number of spells

0 500 1000 1500 20000

1

2x 10

-3 1965-1994

0 500 1000 1500 20000

1

2x 10

-3K

efar

Gila

di

0 500 1000 15000

2

4x 10

-3

0 500 1000 15000

2

4x 10

-3

Tel

Avi

v

0 500 1000 15000

2

4x 10

-3

0 500 1000 15000

2

4x 10

-3

Jeru

sale

m

0 100 200 300 400 5000

0.005

0.01

0 100 200 300 400 5000

0.005

0.01

Bee

r S

hev

a

0 500 1000 1500 20000

1

2x 10

-3 2035-2060

0 500 1000 15000

2

4x 10

-3

2015-2035

0 500 1000 15000

2

4x 10

-3

0 100 200 300 400 5000

0.005

0.01

Change in JSD calculated PDF over time for Change in JSD calculated PDF over time for Average Annual AmountsAverage Annual Amounts

p

mm/yr

shows observed data (red) and calculated past

near future (2015-2035 - dashed) and past calculated

(1965-1990 - solid).

far future (2035-2060 - dashed) and past calculated

(1965-1990 - solid).

0 50 100 1500

0.01

0.02

0.03

0.04

Kfa

r G

ilad

i

1965-1994

0 50 100 1500

0.01

0.02

0.03

0.042015-1035

0 50 1000

0.01

0.02

0.03

0.04

Tel

Avi

v

0 50 1000

0.01

0.02

0.03

0.04

0 50 1000

0.01

0.02

0.03

0.04

Jeru

sale

m

0 50 1000

0.01

0.02

0.03

0.04

0 20 40 60 800

0.02

0.04

0.06

Bee

r S

hev

a

0 20 40 60 800

0.02

0.04

0.06

0 50 100 1500

0.01

0.02

0.03

0.042035-2060

0 50 1000

0.01

0.02

0.03

0.04

0 50 1000

0.01

0.02

0.03

0.04

0 20 40 60 800

0.02

0.04

0.06

Change in JSD calculated PDF over time for Change in JSD calculated PDF over time for Number of Wet DaysNumber of Wet Days

p

Number of Days

shows observed data (red) and calculated past

near future (2015-2035 - dashed) and past calculated

(1965-1990 - solid).

far future (2035-2060 - dashed) and past calculated

(1965-1990 - solid).

0 5 10 15 20 250

0.05

0.1

0.15

0.2

Kfa

r G

ilad

i

1965-1994

0 5 10 15 20 250

0.05

0.1

0.15

0.22015-2035

0 5 10 15 200

0.05

0.1

0.15

0.2

Tel

Avi

v

0 5 10 15 200

0.05

0.1

0.15

0.2

0 5 10 150

0.1

0.2

0.3

Jeru

sale

m

0 5 10 150

0.1

0.2

0.3

0 5 10 15 20 250

0.05

0.1

0.15

0.22035-2060

0 5 10 15 200

0.05

0.1

0.15

0.2

0 5 10 150

0.1

0.2

0.3

Change in JSD calculated PDF over time for Change in JSD calculated PDF over time for Number of Wet SpellsNumber of Wet Spells

p

Number of Spells

shows observed data (red) and calculated past

near future (2015-2035 - dashed) and past calculated

(1965-1990 - solid).

far future (2035-2060 - dashed) and past calculated

(1965-1990 - solid).

2002-1976

1975-1948

Heat waves increase & longer

Frequency of hot & cold spells in July-Aug in both halfs of 1948-

2002

B. Ziv , H. Saaroni, A. Baharad, D. Yekutieli and P. Alpert, "Indications for aggravation in Summer heat conditions over the Mediterranean basin", Geoph. Res. Lett., 32, L12706, doi:10.1029/2005GL022796, 2005.

Durations (days) of hot/cool spells

Distribution of 850 hPa daily temperatures

for 1948-1977 and 1973-2002

Shift in the mode temperatures Increase in extreme events

Changes in T-850 mb distributions over the E. Mediterranean

• Most frequent value increases• Distribution widens• Increase in heat waves & their intensity

B. Ziv , H. Saaroni, A. Baharad, D. Yekutieli and P. Alpert, "Indications for aggravation in Summer heat conditions over the Mediterranean basin", Geoph. Res. Lett., 32, L12706, doi:10.1029/2005GL022796, 2005.

Climatic TrendsClimatic Trends

"Trends in Middle East climate extreme indices from 1950 to

2003",

X. Zhang, E. Aguilar, S. Sensoy, H. Melkonyan, U. Tagiyeva, N. Ahmed, N. Kutaladze, F. Rahimzadeh, A. Taghipour, T. H. Hantosh, P. Alpert, M. Semawi, M. K. Ali, M. H. S. Al-Shabibi, Z. Al-Oulan, T. Zatari, I. Al Dean Khelet, S. Hamoud, R. Sagir, M. Demircan, M. Eken, M. Adiguzel, L. Alexander, T. C. Peterson, and T. Wallis,

"Trends in Middle East climate extreme indices from 1950 to 2003", J. Geophys. Res., 110, D22104, doi:10.1029/2005JD006181, 2005

TX90p

TN90p

Top 10PercentilesTmax/min

Recent20 y dramatic

TX90p

TN90p

Top 10PercentilesTmax/min

Solid triangles5% significanceTurkey- recent & TN More significant

Annual Precipitation Anomalies

Precipitation variation is characterized by strong interannual variability without any significant trend in any of the indices

Mediterranean Changes in P: 1980-2002 vs. 1931-79

Actual change in annual means

(mm)Data from UEA TS2p1

t-test (95% confidence highlighted)

Y. Kushnir 2009

Max 1 day Precipitation Amount

Annual TotalPrecipitation

Zhang et alJGR, 2005

Middle East- Mixed trendsUnlike most Mediterranean

Conclusions

• Tendency to extreme in daily and seasonal rainfall- Desertification?

• Tendency to extreme temperatures• Japanese run confirms how crucial are

high-resolution climate runs• First High Resolution Model Ensemble

over the E. Mediterranean confirms the tendency to extreme along with less total rainfall

Conclusions• The 20km GCM data better represents the precipitation

region over the Middle east region, an increasing evaporation with the magnitude of 150-200 mm/season at the water bodies of EM are projected; a significant decrease of precipitation was found over west Turkey, west Syria, entire Israel and Lebanon, with a magnitude of over 200 mm/wet seasonat the end of this century. The famous “Fertile Crescent” precipitation strip becomes much drier.

• For the current climate, the E of the eastern Mediterranean sea (EMS) is higher than that of western Mediterranean sea (WMS) with a average value of 0.4 mm/day, but with the precipitation it is opposite, i.e. less than in the WMS with an average value of 0.32 mm/day. For the future, the evaporation increases for the EMS are higher than that of WMS, with the average value of 0.45 and 0.22 mm/day respectively; while the precipitation decreases for the WMS are higher than that of theEMS, with the average value of -0.21 and -0.16 mm/day.

• The separated calculated boundary moisture flux balance the moisture budget equation quite well, the main source of moisture for the precipitation over the Mediterranean comes from the west and north boundaries. The evaporation acts a significant positive role to the precipitation of Mediterranean.

• Even the numbers of precipitation events decrease in the future, however, the absolute value for the largest precipitation category shows a increasing trend.

• The decrease of river flow, increase evaporation and decrease precipitation make the water crisis available over the study area at the end of this century.