An alternative method for backscatter retrievals – implemented as plugin in the EARLINET SCC module ELDAmwl

ELDAmwl is an open source software package in python. It is available at https://github.com/actris-scc/ELDAmwl. ELDAmwl is designed in a modular and flexible way. There are two ways of contributing to the project. First, the traditional approach of cloning the repository, developing new features and then submitting a merge request. But, there is also the way to download the code and replace certain parts by self-developed plugins. In this way, the original code can remain completely unchanged and the contributor can test the new plugins with their local installation of ELDAmwl. The repository comes with test data and documentation on how to write plugins. Profiles of particle backscatter coefficients are derived in ELDAmwl with the Raman method (for night-time data) and an implementation of the Klett-Fernald algorithm with backward integration. In this contribution we describe an alternative method for the retrieval of backscatter profiles and how it is implemented in ELDAmwl as a plugin. The new method improves the data availability in twilight conditions in which the Raman method usually cannot be applied.