Wind field and gust climatology of the Persian Gulf during 1988–2010 using in-situ, reanalysis and satellite sea surface winds

This study aimed to investigate the wind-field and gust climatology of the Persian Gulf (PG), using three offshore wind-field resources, including data buoys, ERA-Interim/ERA5 as reanalysis datasets, and satellite-based observations, collected from the National Climatic Data Center-Blended Sea Winds (NCDC-BSW) dataset. Upon the verification of the in-situ observations via estimations in the reanalysis and satellite data, the wind fields were extracted, and then the long-term wind trends were retrieved and compared with the document released by the International Map Collectors’ Society (IMCoS). The study results demonstrated a relative increase and decrease in the wind trends estimated by the reanalysis and satellite data, respectively. The long-term investigation of the rising and falling trends at different stations also established the effect of the summer and winter Shamal (viz. strong northwesterly wind) on the minimum and maximum wind speed and the wind regime over the PG region. Accordingly, June was estimated with high wind speed, mostly corresponding to the summer Shamal. The winter Shamal was also seen in wind gusts in February over the central area of the PG. As for the ERA5 data, the comparisons illuminated general improvements in the results, and the wind speed estimated by the reanalysis ERA5 data in winter outweighed that in summer. The reanalysis estimations were further effective in Qeshm Island and the satellite-based ones were better correlated in Asaluyeh. It was concluded that the reanalysis suffered from limitations in estimating high winds and the satellite observations were facing challenges at very low wind speeds. The gustiest winds, estimated by the IMCoS, were also coming from the west or the northwest of the PG, and most wind gusts were estimated in February. This was consistent with the reanalysis ERA-Interim wind-gust data that had estimated the highest values over the central area of the PG, but with lower wind speeds, indicating a general weakness of the reanalysis data in accurately detecting the patterns in the midscale, e.g., gusts.