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Rainfall
Published in David Butler, Christopher Digman, Christos Makropoulos, John W. Davies, Urban Drainage, 2018
David Butler, Christopher Digman, Christos Makropoulos, John W. Davies
Three main types of weather radar are available depending on the wavelength of the transmitted signal (from larger to shorter length): S-band, C-band, and X-band. The large wavelength radars, such as the S-band, are able to cover larger areas, given that they are not easily attenuated; however, there are problems associated with the interaction of the beam with the ground and the vertical variation of reflectivity. S-band radars are the biggest and most expensive given that larger dishes are needed to achieve a small beam width. On the contrary, C- and X-band radars require less power and possess smaller dishes, but sensitivity to attenuation is a critical issue. C-band radars balance power, size, and cost and are widely used in European countries, along with S-band units. X-band radars are more sensitive and can detect tiny droplets and, therefore, are often used to provide very short-term weather observations and forecasts that are of interest to urban hydrology applications such as early warning systems.
Physical Aspects of Radiofrequency Radiation Dosimetry
Published in Marko Markov, Dosimetry in Bioelectromagnetics, 2017
Marko S. Andjelković, Goran S. Ristić
Safety applications are related to the use of RF radiation for safety purposes, and typical examples are: RFID (radiofrequency identification) systems used in the identification and tracking of objects.Electronic article surveillance for prevention of theft in establishments such as shops.Military radar for controlling/tracking airborne objects.Radar used in air traffic control for guidance and surveillance of civil planes.Weather radar used in weather forecasting to identify precipitation data.
Radio Devices for Remote Sensing
Published in N.A. Armand, V.M. Polykov, Radio Propagation and Remote Sensing of the Environment, 2004
Parameters Parameters A=200 and b=1.6 are used for rain, and A=2000 and b=2.0 are used for snow in moderate latitudes.89 Weather radar applications are used in meteorological services and aviation. Recently, they have also found application in space research along with the help of so-called rain radars.91,92
A Brief review of flood forecasting techniques and their applications
Published in International Journal of River Basin Management, 2018
Sharad Kumar Jain, Pankaj Mani, Sanjay K. Jain, Pavithra Prakash, Vijay P. Singh, Desiree Tullos, Sanjay Kumar, S. P. Agarwal, A. P. Dimri
The critical meteorological input in FF is observed and/or forecasted precipitation (Krzysztofowicz 1999, Marty et al. 2013). Forecasted precipitation is typically derived from quantitative precipitation forecasts (QPF) by numerical weather prediction (NWP). The grid size of NWP can be a major source of error in rainfall forecast, which is further aggravated by the positional error of these grids. Even observed precipitation can have significant uncertainties. Rain gauges sample a very small area and there can be large gaps between them, which can translate into large precipitation errors, particularly in mountainous areas (Stanton et al. 2016). Weather radars can sample large areas but do not directly measure rainfall and there are issues with conversion from reflectivity to rainfall (Catchlove et al. 2005). Flood producing storm events typically occur at highly localized scales (<10 km²) and may not be captured by gridded remotely sensed products, such as TRMM (Stanton et al. 2016).