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E. A. Agosta et al.
Keywords Flood hazards · Vulnerability · Climate change · Subtropical Argentina
Introduction
Exposure to flooding is one of the most common natural hazards that global population faces. It is estimated that about 11% of people are currently living in flood-prone
areas and 1% of the global population is, on average, exposed to floods each year
(UNISDR 2011). In turn, these extreme weather events are imposing significant
costs worldwide, in terms of both human lives and the economy. In agreement with
the World Resources Institute, about 100 billion dollars are lost every year due to
floods, and while the bulk of these economic costs is concentrated among developed
countries, most of the deaths occur in the developing world (IFRC 2014).
Factors influencing floods are related to increased localized and regional precipitation, which further affects river overflows, particularly enhanced by climate change,
population and land use changes due to urbanization, deforestation, or agricultural
expansion as well as changes in crop types. For instance, growth of the urban fabric
toward more hazardous areas increases population vulnerability, especially affecting
those social sectors of lower resources that have no other possibilities rather than to
settle in floodplains. Flood-induced welfare losses then rebound negatively upon the
most vulnerable sectors of society, who often have neither access to public aids nor
adequate social safety nets.
Our focal point is to explore the roles of climatic and socioeconomic factors
contributing to floods over eastern subtropical Argentina (ESA), a vast region of
plains and shallow hills, located to the north of 40°S and east of 65°W in southeastern South America (Fig. 1). The region is highly populated hosting over 60%
of Argentina’s population, in which agriculture is highly developed, comprising the
core region of crop farming in the country. Owing to its geomorphologic, hydrologic,
and climatic features, ESA is a territory vulnerable to floods (Latrubesse and Brea
2009). Annual total precipitations widely exceed 1000 mm in most areas (Fig. 2).
Major rivers cross the region from north to south, such as the Paraná and the Uruguay,
as being part of the southern outflow area of the Río de la Plata basin. The hydrologic
cycle shows strong inter-annual and interdecadal variability forced by natural and
human-induced climate variations (Antico et al. 2014; Doyle et al. 2012).
It is known that modeled climate projections under global warming, induced by
increased greenhouse gas (GHG) concentrations, indicate long-term climate changes
and trend changes in the hydrological cycle worldwide, directly impacting on population’s welfare (IPCC 2013). The climate change is expected to cause an intensification of the water cycle, which could be manifested by regional steady changes
in precipitation, evaporation (evapotranspiration), river discharges, and increased
risk of exacerbated extreme phenomena associated with them (Westra et al. 2013).
Nonetheless, regional trends and changes in hydrological variables can be upward or
downward, depending on the balance between precipitation and evapotranspiration.
The latter highly relies on the land cover which, in the case of southeastern South
E. A. Agosta et al.
Keywords Flood hazards · Vulnerability · Climate change · Subtropical Argentina
Introduction
Exposure to flooding is one of the most common natural hazards that global population faces. It is estimated that about 11% of people are currently living in flood-prone
areas and 1% of the global population is, on average, exposed to floods each year
(UNISDR 2011). In turn, these extreme weather events are imposing significant
costs worldwide, in terms of both human lives and the economy. In agreement with
the World Resources Institute, about 100 billion dollars are lost every year due to
floods, and while the bulk of these economic costs is concentrated among developed
countries, most of the deaths occur in the developing world (IFRC 2014).
Factors influencing floods are related to increased localized and regional precipitation, which further affects river overflows, particularly enhanced by climate change,
population and land use changes due to urbanization, deforestation, or agricultural
expansion as well as changes in crop types. For instance, growth of the urban fabric
toward more hazardous areas increases population vulnerability, especially affecting
those social sectors of lower resources that have no other possibilities rather than to
settle in floodplains. Flood-induced welfare losses then rebound negatively upon the
most vulnerable sectors of society, who often have neither access to public aids nor
adequate social safety nets.
Our focal point is to explore the roles of climatic and socioeconomic factors
contributing to floods over eastern subtropical Argentina (ESA), a vast region of
plains and shallow hills, located to the north of 40°S and east of 65°W in southeastern South America (Fig. 1). The region is highly populated hosting over 60%
of Argentina’s population, in which agriculture is highly developed, comprising the
core region of crop farming in the country. Owing to its geomorphologic, hydrologic,
and climatic features, ESA is a territory vulnerable to floods (Latrubesse and Brea
2009). Annual total precipitations widely exceed 1000 mm in most areas (Fig. 2).
Major rivers cross the region from north to south, such as the Paraná and the Uruguay,
as being part of the southern outflow area of the Río de la Plata basin. The hydrologic
cycle shows strong inter-annual and interdecadal variability forced by natural and
human-induced climate variations (Antico et al. 2014; Doyle et al. 2012).
It is known that modeled climate projections under global warming, induced by
increased greenhouse gas (GHG) concentrations, indicate long-term climate changes
and trend changes in the hydrological cycle worldwide, directly impacting on population’s welfare (IPCC 2013). The climate change is expected to cause an intensification of the water cycle, which could be manifested by regional steady changes
in precipitation, evaporation (evapotranspiration), river discharges, and increased
risk of exacerbated extreme phenomena associated with them (Westra et al. 2013).
Nonetheless, regional trends and changes in hydrological variables can be upward or
downward, depending on the balance between precipitation and evapotranspiration.
The latter highly relies on the land cover which, in the case of southeastern South