54
E. A. Agosta et al.
allowing insurance providers to hedge risk effectively across space and time. In this
sense, the hindered development of flood-related insurance in the country points to the
widespread existence of misconceptions related to the level of exposure to floods.
Public opposition to these schemes could be significant, not least because public
perception of the hazard threat might be attenuated after several years without major
flooding and its consequence (Penning-Rowsell 1996). Besides, once a flood catastrophe occurs, people would assume the government will provide partial financial
assistance as usually done in the past.
Conclusions
This research has aimed at exploring the roles of climate and socioeconomic components contributing to floods over ESA, the eastern portion of subtropical Argentina
characterized by specific geomorphological, climatic, and hydrological features that
make it highly vulnerable to floods. The national structural flood risk map, built
upon the MFM index, shows that the region manifests the flood riskiest areas in the
country. Within ESA, high flood risk values are observed in those municipalities with
the major population settlements. Although decadal mean MFM values have peaked
in the 1980s, there is a positive trend of flood risk along the decades over the highly
populated GBA, contrarily to what is recorded for the remaining of ESA. This trend
of increasing flood risk in GBA is worrisome given the fact that migration rates are
higher there, especially in municipalities recording higher structural flood risks.
One major natural factor to consider is flood hazard due to precipitation extreme
events. Annual total precipitation has increased roughly 15% on average in the last
five decades. A considerable fraction of such an increase is due to more contribution
from daily strong precipitation events, which have increased about 30% on average,
especially over GBA and northeastern ESA. The upper basin of the Paraná River
is subject to increase precipitation which in turn contributes to positive streamflow
trend. Deforestation appears to be a high-pressure factor since over 25% of forest
land has been since 1990 favoring flooding due to decreased evapotranspiration
and limited soil water storage capacity. Future RCP8.5 projections indicate that the
hydrological variables will rise by the end of the twenty-first century, particularly
exacerbating extreme events of precipitation and streamflow peaks.
Besides these climatic trends and projections over ESA, another critical aspect that
makes the region further vulnerable to floods is the lack of continuous and planned
flood management policies at the national or subnational levels. For instance, there
is no active monitoring system which might be used to implement an early warning
system preventing flood damages or flood insurance programs that might help dealing
with effective losses. Despite having a national forest law sanctioned in 2007 by the
National Parliament to harmonize land use, environmental and socioeconomic issues,
the law has not been fully implemented yet due to the lack of allocated funds.
We think that these results, though preliminary in character, can provide policymakers with a compass to guide future planning to deal with the issue of floods and
E. A. Agosta et al.
allowing insurance providers to hedge risk effectively across space and time. In this
sense, the hindered development of flood-related insurance in the country points to the
widespread existence of misconceptions related to the level of exposure to floods.
Public opposition to these schemes could be significant, not least because public
perception of the hazard threat might be attenuated after several years without major
flooding and its consequence (Penning-Rowsell 1996). Besides, once a flood catastrophe occurs, people would assume the government will provide partial financial
assistance as usually done in the past.
Conclusions
This research has aimed at exploring the roles of climate and socioeconomic components contributing to floods over ESA, the eastern portion of subtropical Argentina
characterized by specific geomorphological, climatic, and hydrological features that
make it highly vulnerable to floods. The national structural flood risk map, built
upon the MFM index, shows that the region manifests the flood riskiest areas in the
country. Within ESA, high flood risk values are observed in those municipalities with
the major population settlements. Although decadal mean MFM values have peaked
in the 1980s, there is a positive trend of flood risk along the decades over the highly
populated GBA, contrarily to what is recorded for the remaining of ESA. This trend
of increasing flood risk in GBA is worrisome given the fact that migration rates are
higher there, especially in municipalities recording higher structural flood risks.
One major natural factor to consider is flood hazard due to precipitation extreme
events. Annual total precipitation has increased roughly 15% on average in the last
five decades. A considerable fraction of such an increase is due to more contribution
from daily strong precipitation events, which have increased about 30% on average,
especially over GBA and northeastern ESA. The upper basin of the Paraná River
is subject to increase precipitation which in turn contributes to positive streamflow
trend. Deforestation appears to be a high-pressure factor since over 25% of forest
land has been since 1990 favoring flooding due to decreased evapotranspiration
and limited soil water storage capacity. Future RCP8.5 projections indicate that the
hydrological variables will rise by the end of the twenty-first century, particularly
exacerbating extreme events of precipitation and streamflow peaks.
Besides these climatic trends and projections over ESA, another critical aspect that
makes the region further vulnerable to floods is the lack of continuous and planned
flood management policies at the national or subnational levels. For instance, there
is no active monitoring system which might be used to implement an early warning
system preventing flood damages or flood insurance programs that might help dealing
with effective losses. Despite having a national forest law sanctioned in 2007 by the
National Parliament to harmonize land use, environmental and socioeconomic issues,
the law has not been fully implemented yet due to the lack of allocated funds.
We think that these results, though preliminary in character, can provide policymakers with a compass to guide future planning to deal with the issue of floods and