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Table of Contents
Instruments operated by IGMK
The Atmospheric Emitted Radiance Interferometer (AERI)) measures downwelling infrared radiation from 3-25 µm at less than one wavenumber resolution to derive profiles of tropospheric temperature and humidity. It is also sensitive cloud properties and CO2.
Our ceilometer CT25K is based on the light detecting and ranging (LIDAR) principle: it sends out laser pulses and measures the backscattered light (at 905 nm). From the time delay it derives cloud base height (i.e. the ceiling in aviation) as well as boundary layer structures. For background information see the EG-CLIMET wiki
IGMK's scanning cloud radar MIRA. is a pulsed Doppler radar which measures profiles of reflectivity, Doppler velocity, Doppler spectral width, and linear depolarization ratio at 35.5 GHz. From these, various macro- and microphysical properties of clouds and precipitation can be derived.
Microwave radiometers measure spectral radiance emitted and scattered by atmospheric gases and hydrometeors. IGMK operates Humidity And Temperature PROfilers (HATPRO) which are suited for continuously monitoring the hemispheric distribution of cloud Liquid Water Path (LWP) and Integrated Water Vapor (IWV) as well as tropospheric temperature profiles.
Additionally, IGMK operates the Dual Polarization Radiometer (DPR) which measures in mm wavelength atmospheric windows for snowfall and super-cooled liquid water retrieval. Formerly, within an ESA-study, we operated the ATmospheric PRopagation and Profiling system (ATPROP) to better quantify atmospheric perturbations on satellite signals. Click here for a list of relevant references.
The Micro Rain Radar (MRR) is a vertically pointing FM-CW Doppler radar operating at K-band. From the Doppler spectra the radar reflectivity factor (Ze) and the terminal fall velocity distribution as well as microphysical rain properties can be derived.
A Scintillometer measures the path-averaged structure parameter of the refractive index of air over horizontal path. In combination with standart meteorological observations (air temperature, wind speed, and air pressure) this can be used to derive the surface sensible heat flux. .
A SODAR is a wind profiler based on the SOnic Detecting And Ranging principle. A sound is emitted and backscattered at inhomogeneities of the temperature field. Travel time of the backscattered sound signal is related to distance, Doppler shift gives the wind speed along the sound beam. Several tilted sound beams allow to infer the vector components of the wind.
A Total Sky Imager (TSI) is used to identify cloud types and cloud coverage and complements our cloud liquid water observations.
The Wind Lidar Wind Lidar sends out pulses of light in the near-infrared part of the spectrum. The Doppler shift of the signal backscattered by aerosol can be used to infer line-of-sight wind speed within the boundary layer. Scanning in elevation and azimuth allows derivation of the full wind vector.