A Flexible, Multi-Instrument Optimal Estimation Retrieval for Wind Profiles

Instruments such as Doppler lidars, radar wind profilers and uncrewed aircraft systems could be used in observation networks to fill in the temporal and spatial gap that exists for low level wind observations. These instruments, however, do not directly observe the wind and require a retrieval to be used to obtain wind estimates from their observations. Also, the depth and uncertainty of observations collected by these instruments varies depending on the environment that they are sampling. Optimal estimation is a variational retrieval method that combines information from a prior data set and observations to retrieve an atmospheric state. This technique can be beneficial to use when observations have large uncertainties or provide insufficient information to obtain the atmospheric state by themselves. A new optimal estimation retrieval for obtaining wind profiles from typical lower atmosphere wind profiling instrumentation has been developed. This retrieval allows for more observations from wind profiling instrumentation to be used when retrieving wind profiles, increases the depth of retrieved profiles, and eliminates vertical data gaps. This retrieval can also be used to easily combine observations from different instruments or even with model data to create combined data wind retrievals that leverage the strengths of the different data sources to retrieve a wind profile that is superior to those obtained by the individual observations or data sources. It is envisioned that this retrieval will be continued to be developed and maintained as community software as lower atmosphere wind observing capabilities further develop and expand.