chapter - Atmospheric and Oceanic Science

The production of hydraulic power is influenced by precipitation variability.
The changes of streamflows to take place as a consequence of the Global Climatic
Change, will be able to either favour or hinder the generation of hydraulic power
depending not only on how is the total generation affected but also its seasonal variation
in relation with the demand of electricity. In case changes were unfavourable,
the vulnerability of the electrical sector will depend to a great extent on the percentage
of hydroelectric generation. Therefore, the electric power generation in the La
Plata basin is potentially highly vulnerable to the Climatic Change being from this
point of view one of the regions of the world of greater vulnerability.
The vulnerability to the climatic variability and eventually to Climate Change
can increase in the future since only a fraction of the technically exploitable potential
of hydroelectric energy in the countries of the La Plata basin is being used.
Therefore, the region would be in conditions to increase the installed hydraulic
power during this century to satisfy the increasing demands, even if the climate
change leaded to some reductions in the energy generation in certain dams.
b. Large hydroelectric utilities
The main services and problems of water resource
The need to diminish the vulnerability of the society to Climate Change is
increasingly receiving the attention of governments and international agencies. It is
likely that the most serious consequence of global warming for human beings will
not be the warmer climate, but the changes in the pattern of the hydrology. At global
scale, unprecedented changes are already being perceived, such as a major frequency
and intensity of extreme floods and droughts. It is likely that this situation
will become even worse in the future.
The droughts bring many economic and social prejudices, especially in countries
with great dependence of the agriculture. The impact of droughts in the hydroelectric
generation can also cause economic costs, in moments in which the economy
is already affected by the low production of food and the reduction of exports.
The generation could be reduced substantially and in some cases the reservoirs
could reach extreme low levels like in Itaipú in 1999 and in Salto Grande in 2004.
The big hydroelectric plants are being built assuming that the past hydrological
behaviours can be used to predict the future energy production, the volume of
the floods that should threaten the safety of the dams, the design of the alert programs.
Sometimes these assumptions were exceeded because their designers have
estimated climatic and hydrological scenarios, which are different from what are
currently being observed. This happens as consequence of assuming that the meteorological
and climatic conditions do not change so that the statistical conditions of
the past will be repeated in the future. The least than can be said about this premise
is that it is no longer acceptable. Even with the uncertainties to predict the future
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