A parametric model for ocean wave period from K_u band altimeter data

Abstract

[1] Using a large collocated data set of altimeter and buoy measurements, we examine the relationship between the altimeter Ku-band measurements of significant wave height, H s , backscatter coefficient, s 0 , and the buoy wave period. This is used to derive an empirical altimeter wave period model for TOPEX, Poseidon, Jason-1, ERS-2, Envisat, and GEOSAT follow-on. We show that there is a step change in the response of s 0 at around 13 dB and above this value s 0 is not related to wave period. The results are compared to algorithms proposed by two previous authors (Gommenginger et al., 2003;Quilfen et al., 2004) and examined in terms of absolute accuracy (RMS error), ability to replicate the joint distribution of wave height and period, and residual trends with various parameters. The new algorithm is shown to perform better than the previous algorithms in all metrics considered. Finally, we demonstrate that there is a limiting accuracy achievable for a function of the form f(H s , s 0 ) and that our model comes close to this.Citation: Mackay, E. B. L., C. H. Retzler, P. G. Challenor, and C. P. Gommenginger (2008), A parametric model for ocean wave period from K u band altimeter data,

Comparing wave heights simulated in the Black Sea by the SWAN model with satellite data and direct wave measurements

“…Comparison of SWH data from Gelendzhik buoy, SWAN simulation and the nearest altimetry points. Mackay et al, 2008;Quilfen et al, 2004]. In addition, the physical model from [Badulin, 2014] was used.…”

“…The satellite altimetry data are used for wave climate studies [Chelton and McCabe, 1985]. In [Saleh Abdalla et al, 2011] triple collocation method was used for estimating accuracy of the altimetry data, that are also used for development of mathematical models for wind speeds [Chelton and McCabe, 1985;Goldhirsh and Dobson, 1985;Saleh Abdalla, 2007] and wave periods [Badulin, 2014;Gommenginger et al, 2003;Mackay et al, 2008;Quilfen et al, 2004].…”

Effect of High-Frequency Sea Waves on Wave Period Retrieval from Radar Altimeter and Buoy Data

“…Alternatively, radar altimeters have the capability of estimating H s and wind speed, in addition to the sea surface height. Moreover, subsequent studies have also indicated the possibility of retrieving T z from H s and the backscatter coefficient σ 0 , measurements of altimeters, and numerous empirical models have been proposed in the last two decades (e.g., [2][3][4][5][6]). However, these models perform worse in low-wind conditions than in high-wind conditions.…”

Jason-1/Jason-2 Metocean Comparisons and Monitoring

“…Altimeters are used to study a wide range of metocean measurements -not just wave height and wind speed, but other derived parameters such as wave steepness and period (Mackay et al 2008). Furthermore the different signal backscatter strengths at K u -band and C-band have been used in rain detection algorithms (Quartly et al 1996;Quartly 2004;Tournadre 2004) and in estimating air-sea gas transfer (Frew et al 2007).…”