Precipitation Measurement with Weather
Radars
Nergui Nanding and Miguel Angel Rico-Ramirez
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
2 Sources of Uncertainty in the Estimation of Precipitation with Radar . . . . . . . . . . . . . . . . . . . . . 238
2.1 Radar Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
2.2 Echoes Due to Non-meteorological Origin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
2.3 Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
2.4 Variations in the Vertical Profile of Reflectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
2.5 Variations of the DSD and Radar Rainfall Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
3 Adjusting Radar Rainfall with Raingauge Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
4 Applications of Weather Radar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
4.1 Radar-Based Precipitation Forecasting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
4.2 Hydrological Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
5 Concluding Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Abstract Weather radar is a remote sensing instrument that has been increasingly
used to estimate precipitation for a variety of hydrological and meteorological
applications, including real-time flood forecasting, severe weather monitoring and
warning, and short-term precipitation forecasting. Weather radar provides unique
observations of precipitating systems at fine spatial and temporal resolutions, which
are difficult to obtain through conventional raingauge networks. The potential
benefit of using radar rainfall in hydrology is huge, but practical hydrological
applications of radar have been limited by the inherent uncertainties and errors in
radar rainfall estimates. Uncertainties in radar rainfall estimates can lead to large
errors in flood forecasting applications, so radar rainfall measurements must be
N. Nanding (*)
Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School
of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou, China
e-mail: nanding@mail.sysu.edu.cn
M. A. Rico-Ramirez
Department of Civil Engineering, University of Bristol, Bristol, UK
Andrea Scozzari, Steve Mounce, Dawei Han, Francesco Soldovieri,
and Dimitri Solomatine (eds.), ICT for Smart Water Systems: Measurements and
Data Science, Hdb Env Chem (2021) 102: 235–258, https://doi.org/10.1007/698_2019_404,
© Springer Nature Switzerland AG 2019, Published online: 23 November 2019
235
Radars
Nergui Nanding and Miguel Angel Rico-Ramirez
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
2 Sources of Uncertainty in the Estimation of Precipitation with Radar . . . . . . . . . . . . . . . . . . . . . 238
2.1 Radar Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
2.2 Echoes Due to Non-meteorological Origin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
2.3 Attenuation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
2.4 Variations in the Vertical Profile of Reflectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
2.5 Variations of the DSD and Radar Rainfall Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
3 Adjusting Radar Rainfall with Raingauge Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
4 Applications of Weather Radar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
4.1 Radar-Based Precipitation Forecasting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
4.2 Hydrological Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
5 Concluding Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Abstract Weather radar is a remote sensing instrument that has been increasingly
used to estimate precipitation for a variety of hydrological and meteorological
applications, including real-time flood forecasting, severe weather monitoring and
warning, and short-term precipitation forecasting. Weather radar provides unique
observations of precipitating systems at fine spatial and temporal resolutions, which
are difficult to obtain through conventional raingauge networks. The potential
benefit of using radar rainfall in hydrology is huge, but practical hydrological
applications of radar have been limited by the inherent uncertainties and errors in
radar rainfall estimates. Uncertainties in radar rainfall estimates can lead to large
errors in flood forecasting applications, so radar rainfall measurements must be
N. Nanding (*)
Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, School
of Atmospheric Sciences, Sun Yat-Sen University, Guangzhou, China
e-mail: nanding@mail.sysu.edu.cn
M. A. Rico-Ramirez
Department of Civil Engineering, University of Bristol, Bristol, UK
Andrea Scozzari, Steve Mounce, Dawei Han, Francesco Soldovieri,
and Dimitri Solomatine (eds.), ICT for Smart Water Systems: Measurements and
Data Science, Hdb Env Chem (2021) 102: 235–258, https://doi.org/10.1007/698_2019_404,
© Springer Nature Switzerland AG 2019, Published online: 23 November 2019
235