CMAC: Corrected Precipitation Radar Moments in Antenna Coordinates

CMAC 2.0 (Corrected Moments in Antenna Coordinates version 2) is a set of algorithms and code that does corrections to Radar data, but also adds fields to the original data. Using fuzzy logic CMAC also calculates gate IDs such as rain, snow and second-trip. Some other examples of the corrections done are velocity dealiasing and attenuation-corrected reflectivity. Example of fields added are rain_rate_A, velocity_texture and filtered_corrected_differential_phase.

More information can be found at https://www.arm.gov/capabilities/vaps/xsapr-cmac-142

The Atmospheric Community Toolkit is installed in this binder and can be used to download data for CMAC2.0 from ARM Data Discovery. For an example on how to download ARM datastreams from Data Discovery, click here.

All ARM files are in the format that is needed by CMAC2.0 for processing.

CMAC 2.0 and the required environment can be installed by using the instructions below:

git clone https://github.com/EVS-ATMOS/cmac2.0.git
cd cmac2.0
conda env create -f environment-3.6.yml
source activate cmac_env
export COIN_INSTALL_DIR=/Users/yourusername/youranacondadir/envs/cmac_env

You will need to install Anaconda Compilers for the installation of CyLP. These compilers can be found here and differ between OS: https://docs.conda.io/projects/conda-build/en/latest/resources/compiler-tools.html

After the compilers are installed, you should be able to install CyLP with:

pip install git+https://github.com/coin-or/CyLP.git

Scripts such as cmac_animation and cmac_dask require additional dependencies:

source activate cmac_env
conda install -c menpo ffmpeg=version
conda install dask ipyparallel

Note: For ffmpeg, depending on the user's operating system, the version will need to be replaced with corresponding version number found here:

https://anaconda.org/menpo/ffmpeg

Once downloaded, CMAC 2.0 can be used in the terminal. The required arguments are radar_file, sonde_file, clutter_file and config_dict. There are optional arguments such as out_radar, image_directory and sweep for the quicklooks.

An example:

cmac /home/user/cmac2.0/data/radar_file.nc /home/user/cmac2.0/data/sonde
_file.cdf /home/user/cmac2.0/data/clutter_file.nc config_xsapr_i5

Optional arguments can be called by using:

-o -id -sw

There is currently a config.py file with dictionaries for radars. Down the road, radars such as C-SAPR can be added to config.py which then can be called with the config_dict argument.

• Scott Collis
• Robert Jackson
• Zach Sherman