Background and justification of selected algorithm

The multi parameter retrieval consists of several empirical and physical models which are applied and inverted using a specific cost function. Each individual algorithm and method was applied and validated to some extent for previous satellite missions in the past. For ocean surface this includes contributions from [Meissner et al., 2018, Meissner et al., 2014, Wentz and Meissner, 1998, Wentz and Meissner, 2000] and for sea ice [Huntemann et al., 2014, Kaleschke et al., 2012, Mathew et al., 2009, Tian-Kunze et al., 2014, Tonboe, 2005, Tonboe, 2010]. The inversion of the compositional forward model is then performed using an optimal estimation scheme. The method is based on the works of [Pedersen, 1991, Scarlat, 2018, Scarlat et al., 2017, Scarlat et al., 2020] and shares some components with [Rückert et al., 2023]. In addition to the parameters, the method also retrieves an estimate of their individual uncertainties. The output of the multi parameter retrieval is supposed to be valuable additional information and may serve as a priori input for the various ocean and sea ice algorithms.