An external view of the Met Office building at night.

Dawn Harrison

Areas of expertise

  • Radar meteorology

  • Quantitative precipitation estimation

  • Assessment of radar product quality

  • Impact of wind turbines on weather radar

  • Project Management

Current activities

Dawn is a senior scientist working on weather radar network safeguarding. Wind turbines present a particular challenge to weather radar as they can cause contamination of the radar signals which is often detrimental but difficult to distinguish from hydrometeor returns. Dawn assesses the impact of current operational wind turbines on radar product quality in order to help develop objective methods to assess planning applications for proposed wind turbine and other developments which would be close to operational observing infrastructure. She is investigating potential mitigation methods to reduce the adverse impacts of wind turbines on weather radar data.

Dawn is also working on updating methods to assess the quality of weather radar network coverage, to inform the network design process. This is currently important as the Met Office seeks to expand the existing network by the addition of a site in East Anglia and faces pressure to move existing radars to alternative locations, usually to accommodate wind farms at or very near current radar locations.

Dawn works closely with customers, particularly those in the hydrological sector, providing advice on the use of radar based precipitation estimates.

Career background

Dawn starting working at the Met Office in 1989, following completion of a mathematics/physical geography degree at the University of Southampton. During the early 1990's Dawn worked on observation quality and impact studies, including the estimation of sea surface temperatures from satellites. This was the topic for her dissertation completed as part of an MSc in meteorology at Reading University (1992).

In 1993, Dawn moved to the Observations Products group and worked on the development of Nimrod, an automated nowcasting system.

More recently Dawn has worked on weather radar product development, concentrating on improving the estimation of precipitation. Dawn has managed several projects in this area, which have delivered tangible improvements to both radar product quality, reliability and resolution. These include:

  • A review of the weather radar network in England and Wales, on behalf of the Met Office and the Environment Agency, which considered the cost/benefit of different scenarios for network expansion. This paved the way for the establishment of weather radars in Kent and North East England. Dawn received a Met Office excellence award for this piece of work.

  • The development of a pilot European radar data hub. This was a Eumetnet OPERA programme project which established a full European domain radar composite precipitation product for the first time.

  • The Radarnet Algorithm Development project, which sought to improve several aspects of the radar precipitation rate product and resulted in improvements in the identification of spurious radar echoes and improvements to the quality of the UK high resolution (1 km) precipitation rate composite.

  • Development of a Radar Data Quality Management System, which provides end-to-end quality monitoring - enabling quicker diagnosis of radar system and radar data processing issues, thus enabling quicker resolution.