This study analyzed climate change scenarios and their potential impact on water availability for the South-Southeast region (SSR) of Mexico. Precipitation patterns were examined using the Standardized Precipitation Index for three emissions scenarios, Representative Concentration Pathway (RCP) 4.5, RCP 6.0, and RCP 8.5, during the periods of 1960-2016, 2015-2039 (near future), and 2075-2099 (far future). Historical changes in precipitation in the SSR indicated the presence of dry and wet events driven by El Niño-Southern Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multidecadal Oscillation, which are the regional climate modulators. However, the impact of these phases has not been quantified for the future. The results of our climate change projections show that the Grijalva and Usumacinta rivers and surrounding regions (Chiapas and Tabasco) will have an increase in the percentage of dry and wet events in the near future (2015-2039), while there is a medium to low probability of this occurrence in rest of the SSR. By 2075-2099, Grijalva and Usumacinta will continue to have a high probability of dry events due to climate change, and the Yucatan will also exhibit this behavior. RCP 4.5 was projected to be the wettest scenario for the study area, while RCP 8.5 projected an increase in dry events in the area during both periods (2015-2039 and 2075-2099). RCP 6.0 projected a drier 2015-2039 and wetter 2075-2099.

Precipitation patterns in Usumacinta and Grijalva basins (southern Mexico) under a changing climate.

This study analyzes the mean, maximum, and minimum temperatures and precipitation trends in southeast Mexico-Yucatan Peninsula, Central America and the Caribbean regions. The Climate Research Unit (CRU) TS 4.01, with a spatial resolution of 0.5° × 0.5°, was the database used in this research. The trends of the four selected climate variables cover the period from 1960 to 2016. The results obtained show a clear and consistent warming trend, at a rate of about 0.01 °C/year for the entire study region. These results are consistent with some previous studies and the IPCC reports. While the trends of precipitation anomalies are slightly positive (~0.1 mm/year) for southeast Mexico-Yucatan Peninsula and almost the entire Caribbean, for Central America (CA) the trends are negative. The study also presents the correlation between temperatures and precipitation versus El Niño Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) drivers, indicating global warming and frequency signals from the climate drivers. In terms of the near future (2015–2039), three Representative Concentration Pathways (RPC) show the same trend of temperature increase as the historical record. The RCP 6.0 has trends similar to the historical records for CA and southeast Mexico-Yucatan Peninsula, while the Caribbean corresponds to RCP 4.5. In terms of the far-future (2075–2099), RCP 6.0 is more ad-hoc for southeastern Mexico-Yucatan Peninsula, and RCP 8.5 corresponds to Central America. These results could help to focus actions and measures against the impacts of climate change in the entire study region.

Este trabajo tiene como objetivo principal caracterizar la geomorfología de la subcuenca río Mezcalapa en la región hidrológica Grijalva-Usumacinta en el sureste de México usando sistemas de información geográfica (SIG) y una serie de parámetros morfométricos con la finalidad de analizar y comprender el comportamiento morfodinámico e hidrológico de esta subcuenca. Si bien los resultados obtenidos explican el comportamiento hidromorfométrico en la subcuenca, las características hidrológicas y sedimentológicas del río Mezcalapa están definidas por la política de operación de la presa Peñitas (nombre oficial: presa Ángel Albino Corzo). Con esta investigación se busca contribuir y fortalecer el conocimientolocal, como también favorecer la toma de decisiones en los temas de ordenamiento territorial, protección civil, infraestructura y políticas públicas.