Technical Note - Codice LBL di trasferimento radiativo in cielo sereno

In this document, the activities done in the frame of the WP 2100 (Codice di trasferimento radiativo linea- per-linea broadband in clear-sky) are described. The objective of the work package is to support and to contribute to the implementation of the 'very fast' radiative transfer code (called ?-FORUM) and of the retrieval algorithms in the frame of this project for the FORUM mission. The support and the contribution to ?-FORUM have been provided using a sufficiently flexible and accurate Line-By-Line (LBL) radiative transfer code and a retrieval code to: o Perform a validation/comparison of the Level1 (L1) FORUM simulated products (see also DEL008 of this project); o Generate the Optical Depths (OD) to be used by ?-FORUM for the parametrization of the atmospheric gas absorption. Up to now, ?-FORUM used OD generated by the forward model LBLRTM. This document is the completed and final version of the DEL007