Radio Tomography for Atmospheric Science

The recently released United Nations Intergovernmental Panel on Climate Change (IPCC) report 2013, has highlighted a number of significant changes to our global climate. In particular there are indications that there are significant changes in the global hydrological cycle which governs the amount of rainfall we receive and an increased likelihood of the occurrence of certain types of extreme weather conditions. Although, there is no compelling evidence for increased occurrence of severe weather phenomena such as thunderstorms, this caused by the relative lack of small-scale high-resolution observations. Flooding from rain and thunderstorms is the leading cause of deaths associated with natural disasters, being responsible for almost 7 million deaths in the 20th century.

Critically while the general lifecycle of thunderstorms is very well understood, the exact circumstances leading to the development of large thunderstorms are still something of a mystery. The computer based models run by the world's meteorological agencies to predict such events have been continuously improving but are reaching the point where their accuracy is being limited by the number, quality and type of observations (measurements) essential to their operation.

The aim of this research project is to build a new instrument that will be able to make valuable new measurements which will strengthen our understanding of the development of severe thunderstorms. This project will build an instrument that jointly maps moisture fluxes and atmospheric electrical activity with a view to enabling science to better understand the conditions leading up to the formation of thunderstorms. Specifically, the project will develop network of instruments which will produce images using techniques similar to those used in MRI medical imaging scanners. The improved understanding of the formation of thunderstorms will greatly assist the prediction of severe weather and allow better warnings to be issued reducing the risk to human life and property.

The most immediate beneficiaries in terms of the impact of the project are the project partners on this proposal. However in the longer term the technology to be developed in this project has the potential to make a significant impact to improvements to accuracy and timeliness of forecasts of severe weather. In this regard the proposal has potential to have a significant impact on the assessment and management of flood risk making all UK citizens potential beneficiaries.

Economic impact: commercial exploitation by UK SMEs

1. Chronos Technology: In addition to providing expertise on timing and frequency synchronisation the partnership with Chronos offers a potential route to market for commercial exploitation. The University of Bath has a successful existing working relationship with Chronos as a partner in two TSB projects GAARDIAN and SENTINEL. The projects deployed a sensor network of over 30 nodes in strategic location to monitor GPS signals. Similar the sensor developed in this project could potentially be integrated into this system. Intellectual property developed at Bath is currently licensed for use in a number of Chronos commercial products for GPS signal monitoring.

2. Bristol Industrial & Research Associates Ltd. (Biral): is a UK based designer, manufacturer and distributor of instruments for weather measurements, aerosol size, shape and fluorescence analysis and biological detection of airborne hazards. The newly developed sensors currently have the ability to detect lightning discharges at short range distances and options for similar developments to cover long range distances are being explored. As a result, Biral could provide a potential route-to-market and assist with the manufacturing of the novel sensor technology proposed to be developed here.

Impact arising from new data products: end-users

1. Met Office is a potential beneficiary of the research and a project partner. Met Office provided seed-corn funding for the initial examination of the DAB data and is willing to offer in-kind support for the proposal. Specifically this includes access to surface and GPS data for validation and assistance with the provision of sites for the equipment. With the move towards "convective-scale" NWP with grid lengths of around 1 km, there is a critical need for observation data on similar scales to assimilate into the model. Assimilation of water vapour fields into NWP models in pre-storm conditions has the potential to make a substantial impact on the forecast ability of extreme high-intensity convective events.

2. Environment Agency is also potential beneficiary of research. Flood and coastal risk management is one of the ten Environment Agency supporting strategies for 2010-2015. The ability to understand and manage the risk from river and surface flooding is directly connected to the ability of forecast models and observations to produce meaningful and timely data. The impact of this project on the Environment Agency is likely to be indirect through improved high-resolution forecasts via Met Office products. However, the Environment Agency does operate a large number of field stations which may be suitable sites for sensor nodes.