A storm is brewing around 5G in the weather forecasting and scientific community.
There are many ways that 5G technology is predicted to change our lives, for better or for worse. Of all these changes, though, none are probably stranger or more surprising than its anticipated effect on weather forecasting. You might be thinking that that’s not too unexpected, right? After all, 5G is such a monumental leap forward that a technologically-based process like predicting the weather – a process which is heavily reliant on computers and networks of real-time sensors – should naturally progress as well. The problem is that the institution of 5G is now feared to degrade – rather than to improve – our ability to make critical, and often lifesaving, weather forecasts.
Satellites make current weather forecasting remarkably accurate
According to the National Oceanic and Atmospheric Administration (NOAA), 5-day weather forecasts are currently 90% accurate. Satellites (including geostationary, polar-orbiting, and deep space satellites) constantly monitor the Earth’s atmosphere, transmitting frequent updates back to Earth. These data are combined with readings from land and air-based instruments like ground stations, balloons, and specialized aircraft to create a near real-time global “snapshot” of the weather at any time. All this information is then fed into predictive models that produce weather forecasts for virtually any place on Earth. Short-term forecasts are always more accurate than longer-term ones, but even 7-day forecasts are currently boasting an accuracy of 80%.
To understand how important satellites are in the weather forecasting process, consider a 2013 report from the European Centre for Medium-Range Weather Forecasts (ECMWF) on the tracking of Hurricane Sandy on the US east coast in 2012. The sudden left turn taken by Sandy into the coast of New Jersey was anticipated by weather models 4-5 days in advance, likely saving many lives in the ensuing evacuations. According to the ECMWF report, 90% of the data used in the hurricane tracking models came from polar-orbiting NOAA satellites. Without the satellite data, the timely predictions that prompted coastal evacuations would likely not have been made in time.
The 5G frequency problem
So, what does 5G have to do satellites?
The Federal Communications Commission (FCC) ultimately has say over how the communication frequency spectrum is distributed. Otherwise, signals would be overlapping and interfering with one another. To this end, whenever the FCC decides to allocate a particular range of frequencies, it holds an auction to sell the rights for various bands within that range. In 2016 the FCC opened the range of frequencies in the microwave portion of the spectrum above 24 GHz in order to auction the bands required to let 5G work its magic.
This was an immediate concern to meteorologists familiar with weather satellite communications because the frequencies auctioned off for 5G are adjacent to those used by weather satellites. Whenever transmissions are made in certain frequency bands, there is inevitably some leakage into nearby frequencies, although at much lower power. The FCC set limits to the emissions which can be allowed “out of band” by 5G telecommunications carriers, but experts from NOAA and the National Aeronautics and Space Administration (NASA) fear that these limits don’t go far enough to control interference with weather satellites. Their studies estimate a 77% data loss for a particular set of satellites that are used for the detection of water vapor – a vital variable in weather models.
Members of NOAA and NASA met with the US House of Representatives Science Committee’s Subcommittee on Environment to express these concerns this May. Congress has relayed these concerns to the FCC, which is facing mounting pressure to respond.