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LIDAR

Intense laser pulses are sent into the atmosphere. The light that is scattered back from distant particles or molecules is collected and analysed as function of time and frequency shift. The distance between lidar system and sensing volume is given by the round-trip time of the laser pulses and speed of light. From frequency shift the wind profile is deduced by means of the Doppler effect.

Head of the department: Dr. Gerhard Ehret

The department LIDAR develops ground-based, airborne and space-borne lidar systems and applies them for active remote sensing of key meteorological parameter and atmospheric trace gases to facilitate research in weather and climate.

Research areas are:

• measurement of wind and turbulence with coherent and incoherent Doppler Wind Lidar (DWL) methods,
• measurement of water vapour and ozone through Differential-Absorption Lidar (DIAL) techniques,
• measurement ofcarbon dioxide and methane columns by Integrated Path Differential-Absorption Lidar (IPDA),
• determination of optical properties of aerosols and clouds through High Spectral Resolution Lidar (HSRL) techniques,
• assimilation of wind and water vapour fields into numerical weather forecast systems.

Major instruments developed and operated are:

• the ALADIN Airborne Demonstrator (A2D) comprises an UV airborne incoherent Doppler Wind Lidar at 354 nm for the wind profile,
• the WALES Airborne Demonstrator consists of an airborne multi-wavelength H₂O-DIAL at 935 nm and a HSRL system for atmospheric particles,
• ground-based and airborne coherent DWL systems at 2 µm and 1.6 µm for the 3D- wind field, water vapour fluxes, and atmospheric wake vortex studies,
• the TROPOLEX system for ozone,
• ground-based and airborne IPDA Lidar systems for carbon dioxide and methane columns.

The Lidar department supports ESA’s Lidar missions in the orbit through airborne demonstrator experiments, feasibility studies, and validation after launch.