Building a Climatology of Mountain Gap Wind Jets and Related Coastal Upwelling

Abstract

Winds accelerating through coastal topology are capable of generating jets that often result in cold-water upwelling events in near-coast locations. In situ measurements are frequently not available in remote locations for many of the mountain gap locations globally, so to provide a record of these events for researchers, as well as military and commercial interests, this NASA-funded project is demonstrating how remotely sensed satellite data derived products, and fused model and observations, for wind and sea surface temperatures can be used to detect both wind jet and upwelling events. An algorithm was developed to automatically detect gap wind and ocean upwelling events at gulf regions of Central America using the Cross-Calibrated, Multi-Platform (CCMP) ocean surface wind product and the Optimally Interpolated Sea Surface Temperature (OISST) product. Hierarchical thresholding and region growing methods are used to extract regions of strong winds and temperature anomalies. A post processing step further links the detected events to generate time series of these events. Though developed for Central America regions, the algorithm is being extended to apply to other coastal regions so that detected event products are globally consistent. Through collaboration with the Global Hydrology Resource Center (GHRC), a NASA Distribute Active Archive Center, this project is analyzing large climate data records to generate a resulting climatology of wind jet and upwelling events at known geographic locations will be available as a resource for other researchers. Likewise, through integration of the project's analysis techniques with the GHRC's data ingest processing, the identification and notification of new or current events will likewise be openly available to research, commercial and military users. This paper provides a report on the preliminary results of applying the team's approach of identifying and capturing events for selected mountain gap jet locations.