Roles of Coherent Doppler Lidar Sensors and Combinaison with Other Remote Sensors in Existing and Future Observing Networks

Today, many weather observing networks exist that allow to measure key atmospheric parameters mostly close to the ground with synoptic networks or a picture of the earth from satellites. Commonly, these networks are also equipped with weather radar in order to monitor rainfalls and severe weathers in providing reflectivity and wind information. In spite of all these observations, predicting weather over the next few day remain a challenge even within the most resolved numerical models.

This is why there is still a growing and significant investment to upgrade existing weather networks with new, denser and more resolved observations.

One the main limitations of current weather forecast models is the difficulty to establish accurate initial conditions. This required to improve the observations at regional and local scales to monitor non-synoptic and very local meteorological phenomena.  For twenty years from now, coherent Doppler lidars have been studied and used by meteorologists and researchers to better understand aerosol layers, wind effects, turbulence in the planetary boundary layers for many topics from severe weather, interactions of surface and Ekman layers with the ground, convection, or pollutant dispersions. Nowadays, these sensors are becoming more and more reliable, cost efficient and ready to be used for operational observing networks.

This paper will present shortly the last ten years of developments and improvements of coherent Doppler lidars and will then show their capabilities to measure wind, turbulence but also cloud and aerosol layers according to weather conditions. The way to combine such novel sensors with existing networks composed of surface winds, radar wind profilers or weather radars will be discussed. Finally, if completely new networks have to be built, the study will try to work on the most relevant and optimal observations to be implemented in future networks while describing the combination of lidar and microwave radiometers to provide total thermodynamic profiler of the troposphere.