Kipp & Zonen Data Sheet MTP 5 - Kipp & Zonen - #2

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Introduction There are a number of applications in meteorological and environmental sciences where it is desirable to measure the temperature of the atmosphere in the 1000 m closest to the ground. This is part of the Planetary Boundary Layer (PBL). As altitude increases the air temperature falls with a theoretical 'Adiabatic Lapse Rate' of approximately 6.5 °C per 1000 m, but this rate is influenced by a number of factors. Under Adiabatic conditions pollutant gases, aérosols and fine particulates tend to rise into the atmosphere and disperse. However, in the case of a température inversion a layer of warmer air can trap the pollutants close to the ground. This leads to poor air quality events that can last for many hours until the inversion breaks up. By monitoringthe atmospheric température profile in real-timeit is possible to predict the development and break-up of inversions within a spécifie area and actions can be taken to minimise the environmental and health impacts. Many industries have processes which release gasses into the atmosphère, but this should not take place when an inversion is présent. Temperature profiles are an essential input for accurate plume and dispersion modelling. The MTP 5 family of instruments from Kipp & Zonen is specifically designed to provide real-time PBL measurements with all-weather, unattended opération and automatic self-calibration. They require no specialist knowledge to install, maintain and operate or to analyse the data, and are idéal for network use. MTP 5 uses a uniquely designed compact and rugged microwave receiver which is highly sensitive to atmospheric 'black-body' thermal radiation at 5 mm wavelength (60 GHz frequency). MTP 5 emits no radiation and does not require any operating licences. MTP 5 is quick and simple to set up and most versions can be easily transported to different locations. Typically the instrument is mounted on a platform a few meters above ground level or on the roof of a building. The instrument is connected to a PC running the operating software, which stores the data, calculâtes the température profiles using specially developed algorithms, and displays the results graphically every 5 minutes. MTP 5 is unique, in that it requires no specialist knowledge to operate. It self-calibrates and produces the température profiles automatically in all conditions in real time. MTP 5 data are useful for scheduling releases from industrial processes and as inputs to computer models that predict the dispersion of gasses deliberately or accidentally released. Other applications include: • Investigation into urban heat island effects • Monitoring of atmospheric stability at airports • Régional and mesoscale forecastingin meteorology • Input to emergency management Systems of nuclear power stations and petrochemical facilities • Support of energy balance studies and fog forecasting • Research into radio wave and laser beam propagation • Atmospheric chemistry research Choice of Instrument MTP 5 is a remote sensing instrument that measures microwave radiation emitted from the lower 600 -1000 m of the atmosphère, within the Planetary Boundary Layer. The atmosphère is a strong source of radiation but the changes due to température are small, so a very sensitive receiver is required. Unique radiometers and specially designed antennae operating in the 5 mm waveband form the heart of MTP 5. Atmospheric radiation is measured by scanning in angular steps from horizontal to vertical and the operating software processes the data into vertical height and température information. The data is stored and profiles are displayed graphically every 5 minutes, typically showing the température at 50 m height intervais. Measurement principle Applications MTP 5 has important applications in the monitoring of urban air quality. It offers a simple, fast and economical solution for forecasting and for aiding the process of issuing public information. Typically a small network of 2 or 3 instruments is used, one in the city centre and others in areas from which changes in atmospheric conditions originate. Models MTP 5 is a family of instruments sharing design features and components and they have common software and data formats. The choice of model depends on the application and the measurement location characteristics.