# Changelog of LIMRAD94 netCDF files

*author*: Johannes Röttenbacher (johannes.roettenbacher@uni-leipzig.de)
The W-band Doppler cloud radar LIMRAD94 of the Leipzig Institute for Meteorology was operated in a passive stabilization platform on board the RV Meteor during the EUREC4A campaign (Jan - Feb 2020). The stabilization platform corrected for the roll and pitch motion of the ship. In a post processing step the measured mean Doppler velocity was corrected for the ship's heave motion by shifting the Doppler spectra according to the heave rate at the radar. The Doppler spectra were then also dealiased.
Further details about the post processing can be found in Acquistapace et al. 2021. The used code is partly adapted from code written by Claudia Acquistapace and is available via GitHub as part of [pyLARDA](https://github.com/lacros-tropos/larda). 
In addition, the radar reflectivity was despeckled and filtered for ghost-echos.
For further questions please contact: heike.kalesse@uni-leipzig.de

## v1.0
Reflectivity has been filtered and the mean Doppler velocity has been corrected for the heave motion of the ship.

## v1.1
* see [GitHub](https://github.com/lacros-tropos/larda/pull/22) for detailed changes
* minor updates to the meta data
* removed the average NyquistVelocity
* renamed DoppMax to Nyquist_velocity. This parameter holds the Nyquist velocity (folding velocity) for each chirp.

## v1.2
* added the variable hydrometeor_mask which tells you whether there is a signal in the processed reflectivity or not

## Known Issues
* **Resolved** The heave correction delivers wrong results for the second half of the 14.02.2020. The needed ship motion data was missing starting at 3 pm.