Journalartikel

Jahr der Veröffentlichung: 2019

Seiten: 1802-1817

Zeitschrift: Hydrological Processes

Bandnummer: 33

Heftnummer: 13

ISSN: 0885-6087

DOI Link: https://doi.org/10.1002/hyp.13438

Verlag: Wiley

Abstract: 
High-elevation tropical grassland systems, called Paramo, provide essential ecosystem services such as water storage and supply for surrounding and lowland areas. Paramo systems are threatened by climate and land use changes. Rainfall generation processes and moisture transport pathways influencing precipitation in the Paramo are poorly understood but needed to estimate the impact of these changes, particularly during El Nino conditions, which largely affect hydrometeorological conditions in tropical regions. To fill this knowledge gap, we present a stable isotope analysis of rainfall samples collected on a daily to weekly basis between January 2015 and May 2016 during the strongest El Nino event recorded in history (2014-2016) in two Paramo regions of Central America (Chirripo, Costa Rica) and the northern Andes (Cajas, south Ecuador). Isotopic compositions were used to identify how rainfall generation processes (convective and orographic) change seasonally at each study site. Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT) air mass back trajectory analysis was used to identify preferential moisture transport pathways to each Paramo site. Our results show the strong influence of north-east trade winds to transport moisture from the Caribbean Sea to Chirripo and the South American low-level jet to transport moisture from the Amazon forest to Cajas. These moisture contributions were also related to the formation of convective rainfall associated with the passage of the Intertropical Convergence Zone over Costa Rica and Ecuador during the wetter seasons and to orographic precipitation during the transition and drier seasons. Our findings provide essential baseline information for further research applications of water stable isotopes as tracers of rainfall generation processes and transport in the Paramo and other montane ecosystems in the tropics.

Harvard-Zitierstil: Esquivel-Hernandez, G., Mosquera, G., Sanchez-Murillo, R., Quesada-Roman, A., Birkel, C., Crespo, P., et al. (2019) Moisture transport and seasonal variations in the stable isotopic composition of rainfall in Central American and Andean Paramo during El Nino conditions (2015-2016), Hydrological Processes, 33(13), pp. 1802-1817. https://doi.org/10.1002/hyp.13438

APA-Zitierstil: Esquivel-Hernandez, G., Mosquera, G., Sanchez-Murillo, R., Quesada-Roman, A., Birkel, C., Crespo, P., Celleri, R., Windhorst, D., Breuer, L., & Boll, J. (2019). Moisture transport and seasonal variations in the stable isotopic composition of rainfall in Central American and Andean Paramo during El Nino conditions (2015-2016). Hydrological Processes. 33(13), 1802-1817. https://doi.org/10.1002/hyp.13438