10
H.-J. Bolle
temperature wave is larger at the dry inland stations as compared to Mediterranean
coastal sites and the differences between the stations are larger in summer than in
winter. The Mediterranean basin also contains the sites with highest European
annual precipitation of much above 1000 mm at the eastern Adriatic coast and its
hinterland (4600 mm near 42.8 "N, 22.3 E) and less than 100 mm in North Africa
at 32~ N. A differentiated picture of the climate at a selection of operational stations
around the Mediterranean Sea can e.g. be looked up in Wagner (2001).
In Fig. 2 the annual course of average rainfall across Tunisia is presented. It
shows the gradient from the highest winter precipitation at the northwestern coast
to the eastern coast and the inland. Remarkable is that at the more southern stations
often the winter
precipitation maximum
is not in December or
January but in October
and March.
The spatial variability
of the Mediterranean
climate is high even at
relatively small spatial
scales. As an example we
look at the records 1901 -
1970 of a triangle in
Castilla - La Mancha,
Spain, where in 1991
and 1994 the experiment
EFEDA' took place
(Roldan Fernandez,
1988). At the station of
Albacete (699 m) in the
central plateau of Spain,
150 km off the
Mediterranean coast, the
annual rainfall varies
between 185 mm (1950)
and 657 mm (1959). The
absolute maximum and
minimum temperatures
in August are 42C and
8 'c. The maximum
average rainfall (50
mmlmonth) occurs in
35
.... 31 3'N, 232'e
JO
E
2U'N , JOI'E
III
25
It:
+ 3U' N, 272'e
~
~
.. 2e I'N, 2~ , 3'~
III
II.
::Ii
.. 25 7'N. 32 ,7'f
~
16
+- 2II.2'N. 21 I'E
I II II IV V 111 VII VIII IX X XI XII
MONTH
Fig. 1. Annual temperature wave at some sites in North Africa. The
graph shows monthly mean values according to WMO (1999)
z
o
~
a:
u
w
0::
Il.
3 ~ 5 6 7 8 9 10 II I:
MONTH
36 57'N
" 08 4510
J6' S7'N
- 0 4S1O
.. JS 'OJ'N
09 JO"E
36 SON
- I() 1410
Fig. 2. Annual course of precipitation at some stations in Tunisia
after WMO (1999)
I European International Project on Climatic and Hydrological Interactions between Vegetation,
Atmosphere, and Land-surfaces (ECHIV AL) Field Experiment in Desertification-threatened Areas
I
H.-J. Bolle
temperature wave is larger at the dry inland stations as compared to Mediterranean
coastal sites and the differences between the stations are larger in summer than in
winter. The Mediterranean basin also contains the sites with highest European
annual precipitation of much above 1000 mm at the eastern Adriatic coast and its
hinterland (4600 mm near 42.8 "N, 22.3 E) and less than 100 mm in North Africa
at 32~ N. A differentiated picture of the climate at a selection of operational stations
around the Mediterranean Sea can e.g. be looked up in Wagner (2001).
In Fig. 2 the annual course of average rainfall across Tunisia is presented. It
shows the gradient from the highest winter precipitation at the northwestern coast
to the eastern coast and the inland. Remarkable is that at the more southern stations
often the winter
precipitation maximum
is not in December or
January but in October
and March.
The spatial variability
of the Mediterranean
climate is high even at
relatively small spatial
scales. As an example we
look at the records 1901 -
1970 of a triangle in
Castilla - La Mancha,
Spain, where in 1991
and 1994 the experiment
EFEDA' took place
(Roldan Fernandez,
1988). At the station of
Albacete (699 m) in the
central plateau of Spain,
150 km off the
Mediterranean coast, the
annual rainfall varies
between 185 mm (1950)
and 657 mm (1959). The
absolute maximum and
minimum temperatures
in August are 42C and
8 'c. The maximum
average rainfall (50
mmlmonth) occurs in
35
.... 31 3'N, 232'e
JO
E
2U'N , JOI'E
III
25
It:
+ 3U' N, 272'e
~
~
.. 2e I'N, 2~ , 3'~
III
II.
::Ii
.. 25 7'N. 32 ,7'f
~
16
+- 2II.2'N. 21 I'E
I II II IV V 111 VII VIII IX X XI XII
MONTH
Fig. 1. Annual temperature wave at some sites in North Africa. The
graph shows monthly mean values according to WMO (1999)
z
o
~
a:
u
w
0::
Il.
3 ~ 5 6 7 8 9 10 II I:
MONTH
36 57'N
" 08 4510
J6' S7'N
- 0 4S1O
.. JS 'OJ'N
09 JO"E
36 SON
- I() 1410
Fig. 2. Annual course of precipitation at some stations in Tunisia
after WMO (1999)
I European International Project on Climatic and Hydrological Interactions between Vegetation,
Atmosphere, and Land-surfaces (ECHIV AL) Field Experiment in Desertification-threatened Areas
I