Rainfall Estimation Using Commercial Microwave Links: Case Study for Sri Lanka

Abstract:

Commercial microwave links (CMLs) from cellular telecommunication networks provide a valuable “opportunistic” source of high-resolution space-time rainfall information, complementing traditional in situ measurement devices (rain gauges, disdrometers) and remote sensors (weather radars, satellites). Their greatest potential lies in areas with low gauge densities and no weather radars, often in low and middle income countries having a (sub)tropical climate with generally large spatial rainfall variability. Here, the open-source R package RAINLINK is employed to derive link-based rainfall maps covering the majority of Sri Lanka for a 3.5-month period based on CML data from on average 1188 link paths. These are compared to rain gauge data, as well as to data from the Dual-frequency Precipitation Radar on board the Global Precipitation Measurement Core Observatory satellite. Results confirm the potential of CMLs for real-time tropical rainfall monitoring.