CAMBIO CLIMATICO

REPÚBLICA DOMINICANA 2003
The context of the study was developed with the
creation of climatic scenarios, based on general
circulation models and on MAGICC and SCEN-
GEN software models adapted to the data from
the climatic data of the country and applied to
the above mentioned sectors.
An analysis of climatic conditions was conducted
from the period 1961-1990, developing the
climatic baseline of the country in a simulation
of the future climate of the Dominican Republic.
In addition, the representation method was
used, for which it was necessary to design a
combination of emission scenarios and General
Circulation Models (GCMs) that would allow for
the consideration of the greatest possible level of
uncertainty.
This gave way to the availability of various scenarios
for evaluating vulnerability in the different
sectors, with a temporary time horizon that
includes four periods: 2010, 2030, 2050, and
2100, with the goal of evaluating conditions in
the near future so as to sensitize decision makers
and, in turn, to evaluate at such late dates as
2100, and to measure the scope of the impacts.
1.4.1 Water Sector
1.4.1.a) Water Balance for Climate
Change Scenarios
Following are the results of some considerations
regarding the water balance for the climatic
scenarios designed with the CSRT models
(emission scenario IS92c), ECH4 (emission scenario
IS92a) and HADM2 (emission scenario
IS92f). In referring to the emission scenarios,
Limia (personal communication, 2001) notes
the following: (sic)
1.4.1.b) Water Balance Results
for Each Scenario
The CSRT Model estimates a warming over the
next 100 years on the order of 0.7° C and a 4%
increase in rainfall. Although the evaporating
capacity of the atmosphere and real evapotranspiration
increase, the behavior of the rainfall is
sufficient to increase the total runoff.
The ECH4 Model shows an increase of 2.6° C in
temperature and a decrease in pluvial activity
on the order of 10% over the next hundred
years. For this reason, the values of potential
evaporation and real evapotranspiration will
increase, and the total volume of available
water in the country will decrease by 28% with
respect to the baseline.
The HADCM2 Model demonstrates the most
dramatic foreseeable scenario regarding the
availability of water if a significant reduction
in the emission of thermoactive gases is not
achieved. In this climate scenario, there is an
increase in temperature of 4.2° C and a
decrease in rainfall of approximately 60% over
the next 100 years. Consequently, the total volume
of runoff will be reduced by 95% for the
year 2100. The critical situation described in
this model coincides with the results obtained
by the Meteorological Office of the United
Kingdom in 1998, when it noted that the
Eastern Caribbean will be the most arid zone of
any of the scenarios that are modeled.
To have an idea of the impact of this climate
scenario on water resources, spatial distribution
of rainfall, and total runoff for the year
2100, a great decrease in the value of these
variables is observed, demonstrating a structural
change that intensifies the transition
from the most humid zones to the driest and an
expansion of the areas of the country that are
historically the driest.
If one considers that the average population
growth rate (2.31 according to the National
Statistics Office, cited by the UNDP, 2000) will
hold steady during the present century, and if it
is assumed that the current exploitation of water
resources will remain constant (around 3 billion
m3 of water annually), the proposed hydrological
scenarios could be more severe if measures
aimed at a more rational use of water – including
its protection - are not adopted.
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