What is the quality of the air? A number of atmospheric constituents can influence our health or economy. In our group we can measure picometer sized molecules in the air such as O2, H2O, CO2 or NO2. Such free gases can be quantified in complicated environments ranging from landscapes, to industrial plants and furnaces, to modified atmospheres in food packaging and even inside the human body. Such studies are pursued by Tunable Diode Laser Absorption Spectroscopy (TDLAS) and also DIfferential Absorption Lidar (DIAL).
In the nanometer range we encounter aerosols, their impact on the environment and public health greatly depend on their chemical composition and sizes. Through diode laser multiplexing we can accomplish aerosol laser radar in multiple bands such as distinct spectral bands or depolarization bands. This can be used to classify aerosols and distinguish harmful particles from, e.g., natural constituents such as moisture. Out method greatly exceed conventional aerosol lidar in sensitivity and tempo-spatial resolution. For example, this allows us to capture exhaust plumes from individual vesicles with resolution in milliseconds and centimeters. With the Scheimpflug lidar we can also detect single aerosols by which means the size distributions can be estimated.
In the millimeter range we find airborne insects with the Anopheles Gambiae malaria mosquito killing up to a million people per year. In the last year out group have in particular pushed the boundaries of entomological lidar and carried out field campaign in, e.g., Tanzania, China, Ivory Coast and Scandinavia. Surveillance of insect such as disease vectors, agricultural pest or pollinators is facilitated by our extreme time resolution in Scheimpflug lidar down to microseconds. This allows to capture wingbeats of insects and classify them by modulation spectroscopy. In particular, we collaborate closely with animal ecology and the Lund University Mobile Biosphere Observatory (LUMBO).