Effects of projected climate and land use changes on the hydroclimatology of the Iberá Wetland region in Southeastern South America

NATALIA B. MONTROULL; RAMIRO I. SAURRAL; INÉS A. CAMILLONI

Montevideo

Congreso; WCRP Conference for Latin America and the Caribbean: Developing,linking and applying climate knowledge; 2014

WCRP

The Iberá wetland located in La Plata Basin (LPB) is one of the largest continuous freshwater wetlands in the world and host several unique species of flora and fauna, some of them vulnerable and threatened. Wetlands are ecosystems characterized for being covered or saturated by water for all or part of the year. Therefore, the hydrological regime is determinant for their presence and permanence. Both land use changes and climate variability and change modify the hydrological conditions of the systems and consequently could affect the wetlands biodiversity. A detailed knowledge of the hydrological variability in the region is an important tool for the development of better management practices and adaptation strategies for the conservation of the region. For this purpose, we designed hydroclimatic scenarios for the Iberá region using five Global Climate Models (GCM) from the CMIP5 models and the VIC hydrology model specially adapted for this wetland. However, the application of climate information of GCMs for impact studies is challenging due to risk of considerable biases that could be amplified in the impact models. To deal with these biases and in order to account for the uncertainty of bias correction, we used two correction schemes to correct the climate model output: fitted histogram equalization function and quantile-based mapping. Future projections for water level of the Iberá wetland indicate that the use of different correction schemes lead to similar results and that the main source of uncertainty comes from the use of different GCMs. Moreover, the Iberá system showed a stronger dependence on the precipitation changes rather on the temperature ones. Additionaly, an extreme scenario removing the wetland tile in the hydrological model module was considered and compared with the control simulation where the land cover remains unchanged.