CIMR L2 Multi-Parameter-Retrieval ATBD

This repository holds the ATBD (JupyterBook) v2 for a prototype Level-2 Multi-Parameter-Retrieval product for the CIMR mission.

An HTML build of the ATBD is online.

The ATBD was developed in the context of the ESA-funded CIMR DEVALGO study (2022-2024) (contract 4000137493). More information on the DEVALGO study and other ATBDs it produced is available from CIMR-Algos.

Building the ATBD

To build the ATBD, you will need to have Python installed on your system. You can install the required Python packages by running:

```bash

Clone the repository

git clone git@github.com:CIMR-Algos/MultiParameterATBDV2.git cd MultiParameterATBDV2

Create a virtual environment and install the required packages

python -m venv .venv source .venv/bin/activate pip install -r requirements.txt

Install Julia and packages

curl -fsSL https://install.julialang.org | sh -s -- -y juliaup add 1.10

source ${HOME}/.bashrc # assuming you are using bash, starting a new shell would also work

cd book

set environment variables to use the correct python and julia

export JULIACONDAPKGBACKEND=Null export JULIAPYTHONCALLEXE=../.venv/bin/python

install julia kernel for jupyter

note that the julia +version number syntax is a wrapper coming from juliaup which allows to chose the julia version which is called

julia +1.10 -e "using Pkg; Pkg.add([\"IJulia\",\"Revise\"]);Pkg.build(\"IJulia\")"

install julia packages

julia +1.10 --project=../algorithm/algoenv -e "using Pkg; Pkg.instantiate()"

Build the ATBD

make html ```

The ATBD will be built in the _build/html directory.

[!IMPORTANT]
The environment variable DEVALGO_INPUT_DATA_PATH is used to specify the path to the input data. If not set, some notebooks will not run and the book will not compile.

Running the notebooks

For execution as notebooks, the correct path of the python executable must be set using the environment variable JULIA_PYTHONCALL_EXE, just like in the build process. It is probably more robust to use a absolute path to the python executable.

Script for CIMR L1b to L2 SIT processing

The command line script mpr_run.jl can be used to run the retrieval algorithm on a single L1b file. The script takes three arguments:

1. The path to the L1b file
2. The path to the output file
3. The grid to use for the output file (ease2nh, ease2sh)

For example, to run the retrieval on the test scenes from the algorithm folder of the repository, run:

bash julia +1.10 --project=../algorithm/algoenv mpr_run.jl /datapath/SCEPS_l1b_sceps_geo_polar_scene_1_unfiltered_tot_minimal_nom_nedt_apc_tot_v2p1.nc /outputpath/out_polar.nc ease2_nh

the output is a netcdf file in the EASE2 grid of the Northern and Southern Hemispheres at 12.5 km grid spacing.