1. Links of the Mediterranean Oscillation
to mid-latitude and tropical climate dynamics
Jucundus Jacobeit, Stephanie Seubert, Armin Dünkeloh
University of Augsburg

2. Correlations of the Mediterranean annual mean 500 hPa geopotential heigths
with those of Algiers
(inside the dotted lines: statistically significant at the 95% level of confidence) + _
Conte et al. 1989

3. Pattern of the 500 hPa heights at the stations of Algiers and Cairo
(8th order polynominal smoothing and superimposed linear trend)
Cairo
500 hPa (m)
Algiers
Conte et al. 1989

4. Pattern of the 500 hPa heights at the stations of Algiers and Cairo
(with superimposed linear trend and 8th order polynominal smoothing)
Palutikof 2003 (after Conte et al. 1989)

5. Mediterranean Oscillation Index
Conte et al. 1989

6. Mediterranean Oscillation Index (Conte et al. 1989):
Difference of normalized geop. height anomalies
at Algiers and Cairo
Mediterranean Pressure Index (Palutikof 2003):
Difference of normalized pressure anomalies
at Gibraltar and Lod
Mediterranean Circulation Index (Brunetti et al. 2002):
Difference of normalized pressure anomalies
at Marseille and Jerusalem

7. Objectively reconstructed North-Atlantic-European
Luterbacher et al. 2002:
Objectively reconstructed North-Atlantic-European
grids of SLP and 500 hPa geopotential heights,
early versions of temperature and rainfall grids
since 1659 with monthly resolution

8. MO since winter (DJF)
Algiers/
Cairo
Gibraltar/
Lod
Marseille/
Jerusalem

9. Representation of the MO by large-scale circulation patterns

10. first canonical correlation patterns for winter
500 hPa level
20.1%
1000 hPa level
ONDJFM
r = 0.60
with AO
r = 0.72
with NAO
Precipitation
30.4%
first canonical correlation patterns for winter
r ~ 0.80
with various
MO indices
Dünkeloh & Jacobeit 2003

11. Smoothed time coefficients of the first
canonical correlation patterns for winter
Dünkeloh & Jacobeit 2003

12. canonical correlation patterns
SLP
EV = 21.1%
first
canonical correlation patterns
winter (DJF)
Precipitation
EV = 14.6%

13. canonical correlation patterns for
500 hPa
EV = 11.7%
r = 0.50
with NAO
first
canonical correlation patterns for
winter (DJF)
r ~ 0.7
with various
MO indices
Precipitation
EV = 13.4%

14. Smoothed time coefficients of the first canonical correlation patterns
winter (DJF)

15. second canonical correlation patterns
spring (AM)
500 hPa level
1000 hPa level
r = 0.85
p = 0.000
EVgpot = 10.5 %
EVprec = 19.8 %
precipitation
second canonical correlation patterns
r = 0.55
with NAO
r ~ 0.5/0.6
with various
MO indices
Dünkeloh & Jacobeit 2003

16. Smoothed time coefficients of the second
r= 0.85
Smoothed time coefficients of the second
canonical correlation patterns for spring
Dünkeloh & Jacobeit 2003

17. second canonical correlation patterns
summer (JJAS)
500 hPa level
1000 hPa level
r = 0.67
p = 0.000
EVgpot = 12.2 %
EVprec = 10.1 %
precipitation
second canonical correlation patterns
r = 0.45
with NAO
r < 0.4
with various
MO indices
Dünkeloh & Jacobeit 2003

18. Smoothed time coefficients of the second
r= 0.67
Smoothed time coefficients of the second
canonical correlation patterns for summer
Dünkeloh & Jacobeit 2003

19. canonical correlation patterns summer (JJAS) 1660-1990
500 hPa
third
canonical correlation patterns summer (JJAS)
Precipitation

20. Seasonal correlation coefficients between NAO and MO:
Winter:
Spring:
Summer: (-0.13)
Autumn:
(with Gibraltar/Lod, from Palutikof 2003)

21. Conclusions Part I:
The MO is strongly linked to the NAO during winter,
this relationship fades away towards summer
and recovers afterwards
in terms of canonical correlation patterns, the MO patterns
show - from winter to summer -
a gradual weakening with respect to
CC coefficients and % of explained rainfall variances
within this seasonal sequence,
the MO is primarily an upper-level phenomenon

22. Teleconnection studies
(Stephanie Seubert):
March to November
Domain: 20°S – 70°N, 90°W – 150°E

23. Diagram of seasonal sections
for the period March to November:
45 seasonal sections
including 1-month up to 9-month sections
Current number of seasonal section
Length of seasonal section
(number of months)
Starting month of seasonal section

25. Extraction of 9 teleconnection PCs
Teleconnection - PCA
Input variables: correlation maps of 15 regional prec-indices and 45 seasonal sections
cases: grid points
5 levels
1000 hPA
850 hPA 500 hPA 250 hPA
100 hPA
...
Extraction of 9 teleconnection PCs
Varimax-rotated, multi-level PCA:
Scores:
Major teleconnection patterns
Loadings:
Correlation coefficients between PC-Scores and correlation maps

26. Leading teleconnection mode (TPC 1)
EV = 23 %
250 hPA
500 hPA
1000 hPA

27. Loadings of TPC 1 for the 15 prec
Loadings of TPC 1 for the 15 prec.-indices and the 45 seasonal sections (α=0.01)

28. Affinities between ENSO and the MO (JJAS)
Iberian Peninsula
Eastern Medit.
Correlations with 250 hPa level
MOI
NINO3.4 3
TPC 1

29. Pearson – Correlation between MOI and NINO3.4
-0.73 for JJAS

30. and different indices of the MO
Pearson – Correlations
for all the 45 seasonal sections
between NINO3.4
and different indices of the MO

31. Algiers/ Cairo Gibraltar/ Lod Marseille/ Jerusalem
1000 hPa hPa
Algiers/
Cairo
Gibraltar/
Lod
Marseille/
Jerusalem

32. JJASO Correlations of MOI (500) with geopotential heights 1000 hPa

33. JJASO Correlations of MOI (1000) with geopotential heights 1000 hPa

34. JJASO Correlations of NINO 3.4 – index with geopotential heights
1000 hPa
250 hPa
850 Pa
100 hPa
500 hPa
JJASO

35. Conclusions Part II: There are indications for ENSO impacts on the MO:
with negative sign for late summer/early autumn
with positive sign for spring
Opposite centres in the western and the eastern Mediterranean
are confined to the lower troposphere,
in the upper troposphere there is
a change of sign above the eastern Mediterranean

36. Links of the Mediterranean Oscillation
to mid-latitude and tropical climate dynamics
Jucundus Jacobeit, Stephanie Seubert, Armin Dünkeloh
University of Augsburg