Competition over the bandwidths used by mobile phones and time-critical weather transmissions is only part of the story (see Nature 535, 208–209; 2016). In fact, mobile networks are themselves becoming an important tool for monitoring the weather.

Because weather conditions reduce the strength of radio signals transmitted by commercial microwave links in cellular networks, they can act as a virtual environmental-monitoring facility. For instance, commercial cellular data are already being used to track precipitation, fog, near-surface moisture (see, for example, N. David et al. Bull. Am. Meteorol. Soc. 96, 1687–1698; 2015) and dew (O. Harel et al. IEEE Sel. Top. Appl. Earth Obs. Remote Sens. 8, 4396–4404; 2015), and to predict floods (a discovery awarded the World Intellectual Property Organization Medal in 2009).