Climate, Climate Variability and Impacts in the Mediterranean Area: An Overview
67
reduces the probability of rain and the generation of clouds. The vegetation will
suffer not only from extended droughts but also from enhanced temperatures and
increased radiation which in addition reduces transpiration. For the soils the thread
of salinisation and calcification increases. The regrowth of forests is retarded. Strong
precipitation events, the frequency of which presently seem to increase, will not
efficiently replenish natural water reservoirs because of the soil degradation.
Additional artificial water reservoirs will be necessary to cope with the enhanced
water requirements.
UNEP through its Oceans and Coastal Areas Programme Activity Centre
(OCA/PAC) in 1987 launched the Mediterranean Action Plan and supported a
number of studies in this region. The components of this Plan are: Pollution
Monitoring and Research Programme (MED POL), Blue Plan, Priority Actions
Programme, Specially Protected Areas and Regional Oil Combatting Centre.
Already in early reports (Sestrini, Jeftic, Milliman 1989; Jeftic et al. 1992 and 1996)
the impacts of climate change have been estimated based upon the Villach
assessment of the role of carbon dioxide and of other greenhouse gases in climate
variations and associated impacts (Bolin et al. 1986). Inter alia the relationship was
emphasized between a reduction of rainfall respectively elongation of dry periods,
the river flows, the water storage in reservoirs, wind erosion from the dry soils,
sediment transports due to flash floods which reduce the efficiency of reservoirs, and
salt accumulation in the top soils especially in coastal zones. A number of studies
at different coastal sites (Rhodes, Kastela Bay, Syrian coast, Malta, Cres/Losinj
archipelago) have been carried out which emphasize the sensibility of the
Mediterranean system.
7 Conclusions
7.1 What Has Been Learned From Data Analysis?
Paleo-data show that the Mediterranean in its relatively short history as measured
in the geological time scale went through major climate changes in the succession
of which different types of vegetation covers developed. First the changes had
geological reasons caused by plate movements. During the last million years the
glaciations made their impacts. In the succession of these climate changes new
forms of environment and life developed. Though climate provides the boundary
condition for the development of the species, their actual distribution depends on
many other factors as well. The changing vegetation cover and animal population
is closely related to the changes of the hydrological regime.
In historical times the favourable climatic and environmental conditions which
developed through the last climate optimum in the Mediterranean area stimulated
mankind to extraordinary activities on the expense of the natural resources, which
were rigorously exploited. This continued onto a time when climatic conditions
67
reduces the probability of rain and the generation of clouds. The vegetation will
suffer not only from extended droughts but also from enhanced temperatures and
increased radiation which in addition reduces transpiration. For the soils the thread
of salinisation and calcification increases. The regrowth of forests is retarded. Strong
precipitation events, the frequency of which presently seem to increase, will not
efficiently replenish natural water reservoirs because of the soil degradation.
Additional artificial water reservoirs will be necessary to cope with the enhanced
water requirements.
UNEP through its Oceans and Coastal Areas Programme Activity Centre
(OCA/PAC) in 1987 launched the Mediterranean Action Plan and supported a
number of studies in this region. The components of this Plan are: Pollution
Monitoring and Research Programme (MED POL), Blue Plan, Priority Actions
Programme, Specially Protected Areas and Regional Oil Combatting Centre.
Already in early reports (Sestrini, Jeftic, Milliman 1989; Jeftic et al. 1992 and 1996)
the impacts of climate change have been estimated based upon the Villach
assessment of the role of carbon dioxide and of other greenhouse gases in climate
variations and associated impacts (Bolin et al. 1986). Inter alia the relationship was
emphasized between a reduction of rainfall respectively elongation of dry periods,
the river flows, the water storage in reservoirs, wind erosion from the dry soils,
sediment transports due to flash floods which reduce the efficiency of reservoirs, and
salt accumulation in the top soils especially in coastal zones. A number of studies
at different coastal sites (Rhodes, Kastela Bay, Syrian coast, Malta, Cres/Losinj
archipelago) have been carried out which emphasize the sensibility of the
Mediterranean system.
7 Conclusions
7.1 What Has Been Learned From Data Analysis?
Paleo-data show that the Mediterranean in its relatively short history as measured
in the geological time scale went through major climate changes in the succession
of which different types of vegetation covers developed. First the changes had
geological reasons caused by plate movements. During the last million years the
glaciations made their impacts. In the succession of these climate changes new
forms of environment and life developed. Though climate provides the boundary
condition for the development of the species, their actual distribution depends on
many other factors as well. The changing vegetation cover and animal population
is closely related to the changes of the hydrological regime.
In historical times the favourable climatic and environmental conditions which
developed through the last climate optimum in the Mediterranean area stimulated
mankind to extraordinary activities on the expense of the natural resources, which
were rigorously exploited. This continued onto a time when climatic conditions