Dynamical delimitation of the Central American Dry Corridor (CADC) using drought indices and aridity values

Abstract

The Central American Dry Corridor (CADC) is a sub-region in the isthmus that is relatively drier than the rest of the territory. Traditional delineations of the CADC’s boundaries start at the Pacific coast of southern Mexico, stretching south through Central America’s Pacific coast down to northwestern Costa Rica (Guanacaste province). Using drought indices (Standardized Precipitation Index, Modified Rainfall Anomaly Index, Palmer Drought Severity Index, Palmer Hydrological Drought Index, Palmer Drought Z-Index and the Reconnaissance Drought Index) along with a definition of aridity as the ratio of potential evapotranspiration (representing demand of water from the atmosphere) over precipitation (representing the supply of water), we proposed a CADC delineation that changes for normal, dry and wet years. The identification of areas that change their classification during extremely dry conditions is important because these areas may indicate the location of future expansion of aridity associated with climate change. In the same way, the delineation of the CADC during wet extremes allows the identification of locations that remain part of the CADC even during the wettest years and that may require special attention from the authorities.

Aridity Trends in Central America: A Spatial Correlation Analysis

“…For example, one of the aridity increases is located in the headwaters of the Tempisque catchment in Costa Rica. The Tempisque catchment is the largest in the country and an important source of irrigation water in the Costa Rican North Pacific ( [34,35]), a relatively drier zone which is part of the Central American Dry Corridor ( [10,[36][37][38]). Decreasing precipitation trends have also been reported in the Tempisque headwaters by [39] using another dataset.…”

Climate Variability and Change in Central America: What Does It Mean for Water Managers?

“…Socioeconomic vulnerabilities are common in the CADC, as subsistence agriculture is one of the main economic activities. It is known that the delimitation of the CADC have a large year-to-year variability (Quesada-Hernández et al, 2019). Also, it is important to study the future expansion of the aridity associated with warmer temperatures, as this may signal possible associated impacts in human and environmental systems at the borders of the CADC.…”

Asociación entre algunos índices de sequía e impactos socio-productivos en el Pacífico Norte de Costa Rica

“…En todos los cantones estudiados este presenta una alta (baja) probabilidad de muchos (cero) impactos cuando se encuentra en condiciones moderada y severamente secas (húmedas). Lo anterior lo convierte en un índice bastante robusto para los estudios de sequía, al ser frecuentemente recomendado por organizaciones internacionales y además reproduce los patrones de sequía espacialmente de una forma bastante apropiada (Quesada-Hernández et al, 2019).…”

“…El CSC se extiende a lo largo de la vertiente del Pacífico de Centroamérica, desde Chiapas, México hasta Guanacaste en Costa Rica e incluye el Arco Seco de Panamá (CCAD, 2011;Gotlieb et al, 2019). El CSC cambia su tamaño de acuerdo con distintos fenómenos de variabilidad climática, pudiendo aumentar o disminuir durante años, El Niño o La Niña, por ejemplo (Quesada-Hernández et al, 2019). El origen y mecanismos físicos que controlan el clima del CSC pueden ser consultados en diferentes investigaciones (Calvo-Solano et al, 2018;Hidalgo et al, 2015;.…”