Abstract's details
Characterisation of the tropical cyclone induced wave field from satellite observations, in-situ data, and parametric model
CoAuthors
Event: 2022 CFOSAT Science Team Meeting
Session: Wind and waves: characterization, processes, modeling
Presentation type: Type Oral
Contribution: PDF file
Abstract:
The wave field generated by tropical cyclones (TC) can be estimated using high resolution wave models (Chen and Curcic, 2015, Liu et al, 2007, Moon et al, 2003). However, their computational cost is high. Moreover, under extreme wind conditions, the wind field may not always be properly described over time and space and parameterizations of the source terms can be questioned. The present work aims at maximizing the use of observations from different sources including satellite remote sensing and in-situ data to describe consistently the tropical cyclone induced wave field both inside and outside the area of strongest wind speed and the associated wind forcing.
A TC wave atlas has been designed to describe generated wave systems in all directions for each TC track from the IBTrACS database, using microwave altimeters, CFOSAT and Sentinel-1 for waves and scatterometer and Sentinel-1 for wind. Because of the strong rain rate in the case of Ku-band CFOSAT radar and the radar imaging mechanism for SAR, the wave measurement in the inner core is still challenging. Thus, wave systems from Sentinel-1 L2 OCN WV and CFOSAT SWIM L2S measurements far from the TC are back propagated towards their source. This allows for a first description of the outrunning swell properties (wavelength and direction) with respect to the TC properties (intensity, translation speed and size). The use of moored and drifting buoys data could enhance this wave atlas.
In addition, a parametric model dedicated to tropical cyclones, developed in Kudryavtsev et al. 2021, was implemented in order to estimate the propagation path of wave rays inside and outside the cyclonic wind field. Our motivation here is then to rely on the parametric model, assessed thanks to the wave atlas, to produce ensemble simulations to be used as a first guess to help the wave inversion from remote sensing data (especially Sentinel-1 wide swath IW images).
A TC wave atlas has been designed to describe generated wave systems in all directions for each TC track from the IBTrACS database, using microwave altimeters, CFOSAT and Sentinel-1 for waves and scatterometer and Sentinel-1 for wind. Because of the strong rain rate in the case of Ku-band CFOSAT radar and the radar imaging mechanism for SAR, the wave measurement in the inner core is still challenging. Thus, wave systems from Sentinel-1 L2 OCN WV and CFOSAT SWIM L2S measurements far from the TC are back propagated towards their source. This allows for a first description of the outrunning swell properties (wavelength and direction) with respect to the TC properties (intensity, translation speed and size). The use of moored and drifting buoys data could enhance this wave atlas.
In addition, a parametric model dedicated to tropical cyclones, developed in Kudryavtsev et al. 2021, was implemented in order to estimate the propagation path of wave rays inside and outside the cyclonic wind field. Our motivation here is then to rely on the parametric model, assessed thanks to the wave atlas, to produce ensemble simulations to be used as a first guess to help the wave inversion from remote sensing data (especially Sentinel-1 wide swath IW images).