The technology has been around for a few years and has attracted international attention. Researchers are now going to investigate the possibility of develpoing the technology to measure snow and fog, and to use the measurements to be able to better calculate high water flows in the urban environment.
The microwave signal that is transmitted between mobile masts is dampened by precipitation in the air, and this damping of the signal can be converted into precipitation intensity. SMHI has worked together with Ericsson and Hi3G to conduct a successful pre-operational test to measure rain using microwave links in Gothenburg, under the name of MicroWeather.
Rain, snow, fog and floods
In this new project, researchers will both improve the algorithms that calculate the volume of rain and investigate how current and future microwave links can be used to monitor other meteorological variables such as snowfall and fog.
“Too much precipitation can have major consequences, especially in a city where heavy downpours can result in major floods with damage to both roads and buildings. This is expected to become more common as climate changes. So it’s important to develop the methods to measure precipitation, so that we can issue weather warnings and thus provide the emergency services and others with an opportunity to prepare themselves for extreme events,” says Jafet Andersson, researcher at SMHI.
The sewage pipeline system in Stockholm is extensive, with long drainage times in the system, and at the same time there are few rain gauges. The pipeline network to treatment plants is largely combined and transports large volumes of water when there is precipitation. Stockholm Vatten och Avfall see major benefits in being able to have a better spatial resolution of data from rain events and thus gain an improved understanding of flood events, as well as a better estimate of the total volume to treatment plants from the precipitation event.
Compare with traditional measurements
The project Microwave-based Environmental Monitoring (MEMO) is a partnership between SMHI, Ericsson and Stockholm Vatten och Avfall. During the project, they will be collecting precipitation data from microwave links in the mobile telephony network and then analysing and comparing them with traditional measurements of precipitation that take place in the area in order to further develop the technology. In parallel, they will test link-based precipitation data in hydrological forecasting tools in order to see whether and how they can improve the forecasting quality.
The project is being financed by Vinnova and will continue during 2018 and 2019.