TORONTO -- The suspension of commercial flights amid the COVID-19 pandemic is affecting more than just travel plans.

Experts have found that the grounding of thousands of passenger planes has led to a severe decrease in aircraft-based observations, predominantly in Europe and across the Atlantic and Pacific oceans, which help with weather predictions.

The World Meteorological Organization's Lars Peter Riishojgaard told NewsDay by CTV News, a new show on the streaming app Quibi, that fewer planes in the air means there are less reliable weather forecasts.

"As a matter of routine operations, commercial airliners measure every few seconds the temperature of the wind speed or wherever they happen to be located in flight… They do it for their own avionics, but several of the major airlines have agreed to provide th[is] information to the metrological community, and they are a tremendously valuable source of information for us," Riishojgaard said.

"We get about a million a day of these measurements literally from all over the globe and at the present time, we have lost somewhere around 75 to 80 per cent of that information resource," he added.

Riishojgaard said the data from aircrafts is plugged into three-dimensional weather models of the atmosphere to simulate future weather conditions. After satellites, he says aircrafts are the second-most important airborne element in forecasting.

Riishojgaard said the concern with a lack of data from aircrafts is that weather warnings may come too late if the coronavirus pandemic continues into flood and hurricane season.

"This is a statistical game, so you never really know exactly what you're going to lose until after it has happened. But what can happen is that you will lose some of what we call the lead time. So you may be alerted to a certain phenomena two or three days ahead of time instead of perhaps three or four days or in very rapidly developing situations, perhaps the same day instead of a day [or] thirty six hours before," Riishojgaard said.

Environment Canada's Executive Director of National Prediction Development Richard Hogue told CTV's NewsDay on Quibi on Saturday that meteorologists are relying more on weather balloons while aircrafts are grounded. He said that twice as many weather balloons have been launched across the world's 1,300 balloon sites amid the pandemic.

"They run balloons with little instrument that measures temperature, humidity, winds all the way to the stratosphere. That's really important," Hogue said. "Instead of just sending them twice a day, they sending [them] four times a day. We're actually taking advantage of that data because we use the data globally."

Hogue said forecasters are also leaning more on satellites to make up for the missing data to get the full weather picture. However, he said Canada's commercial flights have been only been reduced by approximately 50 per cent so meteorologists still receive some aircraft-based observations.

"We're going to use more satellite derived data like we call them, winds from satellite information on temperature profile from satellites. These two pieces of information will help us in Canada to, in a sense, mitigate without reduction of aircraft," Hogue said.

Hogue said the data gap is not currently big enough for Canadians to notice less accurate weather reports, but Environment Canada is monitoring the situation.

While data taken from satellites is mostly autonomous, Riishojgaard said some satellites in underdeveloped countries still require human intervention to properly track weather observations.

"We are particularly vulnerable over Africa and parts of South America in the developing world where many, many servers still rely on having [someone] go out every few hours, read an instrument and then go back into their office and call in their mission to some central facility before it gets transmitted into the international networks," Riishojgaard said. He said those areas are most vulnerable because their services have sent those staff home due to COVID-19.

Hogue said ocean observations may also be greatly impacted by travel changes from COVID-19 over a long period of time. He said commercial ships and automated buoys that track long-range weather predictions, including the impact of climate change, are not being repaired as often during the outbreak.

"When [buoys] stop reporting because they're fully automated, we've got to go and repair them. Well, we're not going these days and that's a big issue… If you want to repair a buoy, you have to put someone on a ship [and] who wants to go on a ship these days?" Hogue said.

Riishojgaard said the World Meteorological Organization has only lost about 10 per cent of its ocean observing capabilities but cautioned that could increase as the coronavirus pandemic continues.

While the lack of data may not have instant impacts on forecasts, Riishojgaard said there is still a global threat in preparedness for severe weather events.

"We're not going to lose all capabilities altogether and in many situations, perhaps nothing will happen. The forecast will be just as find as it always has, but it increases your level of risk," Riishojgaard said.