Heated negotiations will begin in Egypt this week that could decide the future of 5G and weather forecasting. More than 3,000 delegates, hailing from nearly every country in the world are expected to resolve an ongoing turf war over highly prized radio frequency bands used by meteorologists and coveted by cellphone companies. It’s all going down at the World Radiocommunication Conference in Sharm el-Sheikh, Egypt, where guidelines on the contested frequencies will be decided.

Prominent scientists have already rung the alarm bells on the debut of 5G wireless networks, which promise customers faster internet speeds. The worry is that the rollout could inadvertently throw off weather forecasting, they say, because 5G networks are planning to use a frequency band very close to the one satellites use to observe water vapor. That interference could cost lives and fortunes when it comes to preparing for disastrous weather events.

Cell service providers make a lot of big claims when it comes to 5G, the next generation of mobile broadband. Previous generations of cellular wireless technology, like 4G and LTE, operate along lower radio frequencies. But it’s getting crowded down there. To achieve the superfast speeds, 5G will need to be able to operate at frequencies higher than what existing 4G and LTE are using. One of those frequency bands is just above 24GHz. But just under 24GHz is the frequency at which water vapor molecules emit a little bit of a radio signal, and that’s what makes it so valuable to scientists who are studying the weather. They’re worried that 5G could be a noisy neighbor, unintentionally leaking signals into bands next door, which could interfere with their ability to monitor water vapor. Studying water vapor is important for predicting the trajectory of storms, forecasting sunny weather or rain, and keeping tabs on the changing climate.

“We don’t want to be in any way painted as anti 5G, we just want everybody to be good neighbors,” says Stephen English, a meteorologist at the European Centre for Medium-Range Weather Forecasts in the United Kingdom. “We want to come to a good agreement [in Egypt] where everybody can carry out the services they want to carry out without interference or problems from their neighbors.”

To keep 5G from interfering with forecasting, English and other scientists have pushed for strict limits on the noise that 5G devices are allowed to generate outside of the 24GHz channel. But the US Federal Communications Commission has proposed much less stringent limits, even though concerns over the potential threats to science and public safety have been mounting ever since the FCC decided in March to auction off that part of the radio spectrum. The FCC issues licenses to entities using the airwaves in the United States, and under Chairman Ajit Pai, it has made auctioning off licenses for high-band radio spectrum a priority as part of its goal of securing US leadership in 5G technology. 

In May, National Oceanic and Atmospheric Administration (NOAA) head Neil Jacobs told Congress that the FCC’s proposed interference limits could roll back 40 years of progress on weather forecasting and result in satellites losing nearly 80 percent of the data they’re able to collect now. The resulting inaccuracy could mean real consequences for people on the ground. “If you can’t make that prediction accurately, then you end up not evacuating the right people and/or you evacuate people that don’t need to evacuate, which is a problem,” NASA administrator Jim Bridenstine told Congress in April. 

Rep. Eddie Bernice Johnson (D-TX), who chairs the House Science, Space, and Technology Committee, wrote two letters to the FCC in September and October demanding that the agency provide the scientific analysis behind its decision to propose weaker interference limits. The FCC has yet to respond to her requests. “I am left to assume that the FCC has no science-based evidence to support its position,” Johnson said in an October 23rd statement. The FCC did not respond to a request for comment from The Verge.

The United States will bring its position on allowing more lax limits to the conference in Egypt where international guidelines will be formalized. The meeting is convened every three or four years by the United Nations International Telecommunication Union to review and revise radio regulations. As the summit began, President Trump addressed a letter to the secretary-general of the International Telecommunications Union saying, “We intend to cooperate with like-minded nations to promote security in all aspects of 5G networks worldwide.”

Negotiations begin on Monday, October 28th, and will run through November 22nd. It’ll also tackle the growing demand for radio spectrum used to provide internet connection to “moving targets” like planes and ships. The last conference in 2015 was marked with tough debates on which frequencies to earmark for drones. 

“It’s always a very difficult meeting. You can imagine negotiations going on right through the night, through the next day,” English tells The Verge. But unlike previous conferences, many regional players are coming into this year’s negotiations with established positions. The Inter-American Telecommunication Commission, which includes the United States and 34 other countries across the Americas has proposed emissions limits closer to the FCC’s proposal than the much stricter limits that the meteorological community is looking for. So the outlook in Egypt so far is grim for those hoping for stronger protections from the potential interference 5G could pose to weather forecasting. “I’m not terribly optimistic of a good outcome,” English says.

On top of all that’s at stake when it comes to 24GHz, the decision coming out of Egypt could also set a precedent for other prized frequencies as the radio spectrum becomes more crowded. “This isn’t a one and done with 24GHz. We could be having similar discussions about a few other important bands,” says Jordan Gerth, an atmospheric scientist at the University of Wisconsin at Madison. That’s because satellites use other high-frequency bands to study things like clouds and air temperature. 

Still, even if less stringent interference limits are adopted in Egypt, the worst-case scenarios that meteorologists are worried about won’t come about immediately. 5G hasn’t been widely deployed because the technology and infrastructure to make good on its promises just aren’t there yet. But that tech is slowly being built up, and more developments loom on the horizon. “In the future, we’re going to have 6G, we’re going to have all sorts of people chasing a spectrum,” English says. That’s one reason why experts are placing a lot of weight on this 5G decision in Egypt. The outcome of this battle, English says, will be an early signal of how much world leaders value science and could show whether they will be willing to protect their science in the future.