Abstract
Remote sensing data for space-time characterization of wind fields in extensive oceanic areas have been shown to be increasingly useful. Orbital sensors, such as radar scatterometers, provide data on ocean surface wind speed and direction with spatial and temporal resolutions suitable for multiple applications and air-sea studies. Even considering the relevant role of orbital scatterometers to estimate ocean surface wind vectors on a regional and global scale, the products must be validated regionally. Six different ocean surface wind datasets, including advanced scatterometer (ASCAT-A and ASCAT-B products) estimates, numerical modelling simulations (BRAMS), reanalysis (ERA5), and a blended product (CCMP), were compared statistically with in situ measurements obtained by anemometers installed in fifteen moored buoys in the Brazilian margin (8 buoys in oceanic and 7 in shelf waters) to analyze which dataset best represents the wind field in this region. The operational ASCAT wind products presented the lowest differences in wind speed and direction from the in situ data (0.77 ms−1 < RMSEspd < 1.59 ms−1, 0.75 < Rspd < 0.96, −0.68 ms−1 < biasspd < 0.38 ms−1, and 12.7° < RMSEdir < 46.8°). CCMP and ERA5 products also performed well in the statistical comparison with the in situ data (0.81 ms−1 < RMSEspd < 1.87 ms−1, 0.76 < Rspd < 0.91, −1.21 ms−1 < biasspd < 0.19 ms−1, and 13.7° < RMSEdir < 46.3°). The BRAMS model was the one with the worst performance (RMSEspd > 1.04 m·s−1, Rspd < 0.87). For regions with a higher wind variability, as in the southern Brazilian continental margin, wind direction estimation by the wind products is more susceptible to errors (RMSEdir > 42.4°). The results here presented can be used for climatological studies and for the estimation of the potential wind power generation in the Brazilian margin, especially considering the lack of availability or representativeness of regional data for this type of application.
Highlights
Ocean surface wind is one of the main drivers of several oceanic, atmospheric, and climate processes, being an important indicator of climate change [1]
It can be noted that Advanced SCATterometer (ASCAT) and Cross-Calibrated MultiPlatform (CCMP) products had slightly better results than ERA5. e spatial resolution of the databases seems to influence their performance, with the finest resolution products showing better results than the coarser ERA5 database
If analysis is restricted to oceanic waters (OW) buoys, best performance is observed for CCMP product (Figure 6 and Table S2), showing the lowest errors in terms of RMSEdir and the best values of Rspd and Rdir for 5 or more buoys among the 8 OW buoys compared
Summary
Ocean surface wind is one of the main drivers of several oceanic, atmospheric, and climate processes, being an important indicator of climate change [1]. E vast extension of the global ocean imposes technical and financial limitations on in situ ocean surface winds sampling, which is necessary and valuable in remote sensing calibration and validation process. Direct measurements are acquired by anemometers on moored buoys, research cruises, and vessels of opportunity, or by light detection and ranging (Lidar) sensors, providing precise and accurate data. These techniques are limited to point measurements that are not able to provide satisfactory spatial and temporal coverage to resolve variability at different scales [14]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
