ENSO Influence on Coastal Fog-Water Yield in the Atacama Desert, Chile

Received: January 11, 2017
Revised: July 25, 2017
Accepted: July 28, 2017
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2017.01.0022  

Cite this article:
del Río, C., Garcia, J.L., Osses, P., Zanetta, N., Lambert, F., Rivera, D., Siegmund, A., Wolf, N., Cereceda, P., Larraín, H. and Lobos, F. (2018). ENSO Influence on Coastal Fog-Water Yield in the Atacama Desert, Chile. Aerosol Air Qual. Res. 18: 127-144. https://doi.org/10.4209/aaqr.2017.01.0022

HIGHLIGHTS

• We explore the relation of ENSO and fog-water yields in coastal Atacama Desert.
• We contrast 17 years of fog-water data with atmospheric and oceanographic variables.
• Ocean and atmospheric interrelated functioning are expose at different time and scales.
• ENSO influence on fog and explain 79% of the summer fog water variability.
• Use of fog as a water resource is sustainable under possible future climate scenarios.

ABSTRACT

Fog water represents an alternative, abundant and currently unexploited fresh water resource in the coastal Atacama Desert (~20°S). Here, the stratocumulus clouds meet the Coastal Cordillera, producing highly dynamic advective marine fog, a major feature of the local climate that provides water to a hyper-arid environment. One of the main issues that arises in harvesting fog water is our limited understanding of the spatial and inter-annual variability of fog clouds and their associated water content. Here we assess the role of regional-wide El Niño Southern Oscillation (ENSO) forcing on local inter-annual fog-water yields along the coast of Atacama. We contrast 17 years of continuous fog-water data, with local and regional atmospheric and oceanographic variables to determine the link between them and the inter-annual dynamics of fog in northern Chile. Sea surface temperature (SST) in ENSO zone 1 + 2 shows significant correlations with offshore and coastal Atacama SST, as well as with local low cloud cover and fog water yields, which go beyond the annual cycle beat, exposing a potential causal link and influence of ENSO on fog along the Atacama. On the inter-annual time scale, we found that when ENSO 3 + 4 zone SST, specifically during summer, overcome a > 1°C temperature threshold, they incite significantly higher summer fog water yields and explain 79% of the fog variability. Furthermore, satellite images displaying regional extent Sc cloud and fog presence during ENSO extremes reveal higher cloud abundance during El Niño at this latitude. However, 75% of the yearly fog water is collected during winter, and does not appear to be affected in a significant manner by Pacific oscillations. Thus, our results suggest that the utilization of fog as a fresh water resource may be sustainable in the future, regardless of ENSO-induced variability in the region.

Keywords: Southeast Pacific (SEP); Stratocumulus cloud; Fog-water; El Niño Southern Oscillation (ENSO); Estación Atacama UC Oasis de Niebla Alto Patache.