One week of air traffic in 2019 week commencing 18 Mar One week of air traffic in 2020 week commencing 23 Mar Source: flightradar24.com

Since countries around the world have gone into lockdown to prevent the spread of Covid-19, flight and passenger numbers have made a steep downward plunge. But not all planes are grounded. We’ve taken a look at the available data to find out who is still flying.

How much is air traffic down from normal levels?

A Guardian analysis of Flightradar24 data showed that the number of aircraft transmitting location information and reporting an altitude of more than 50ft had dropped by more than half last week compared to a typical March week last year.

Flightradar24 doesn’t record all commercial flights and conversely it tracks some non-commercial aircraft, but the numbers are in line with other data sources.

Travel data provider OAG reported that the number of scheduled flights this week is down 48% compared to the same week last year. Their figures show the number of scheduled flights has gradually declined since the beginning of March when only 8% of flights had been cancelled.

Why are there still so many planes in the air?

Despite far-reaching travel restrictions in many countries, thousands of flights are still taking off from airports every day.

In the early days of the outbreak, many airlines continued to operate near-empty “ghost flights” to comply with airport slot regulations. These rules require airlines to operate at least some connections at any given time to guarantee they will keep their landing slots in the future.



They have since been relaxed in many legislations, including in the EU which announced on 10 March that it would temporarily suspend slot usage obligations.

But the main reason thousands of planes remain in the air is that governments have been reluctant to restrict domestic air travel.

In the US – the largest air market in the world – the number of scheduled international flights was down 72% this week compared to last year, according to OAG. But domestic flights had only fallen by 18%.

At a White House briefing on Wednesday, President Trump said his administration was considering restrictions on flights between the worst-hit areas of the country.

In the UK, international flights were down 81%, compared to 60% for domestic connections.

One of the few countries to suspend all domestic flights was India, where health experts worry a big jump in coronavirus cases could be imminent.

What’s the impact on the environment?

The large drop in air traffic is expected to lead to a temporary dip in greenhouse gas emissions. Before the coronavirus outbreak, carbon emissions from aviation had been rising consistently, roughly doubling between 1990 and 2019.

Environmental campaigners are demanding that bailout packages for struggling airlines include provisions for large emissions cuts. But last week, the US Senate passed a $60bn relief package with no stipulations on climate action.

In the UK, 26 campaign groups including Greenpeace, Flight Free, the IPPR and New Economics Foundation thinktanks, and Tax Justice wrote to the chancellor on Wednesday saying that any support package must set conditions to “reorientate the industry towards helping to meet the Paris climate agreement.”

One effect of the coronavirus crisis has yet to be felt. Under the carbon offsetting scheme adopted by the International Civil Aviation Organization – known as Corsia – airlines will have to make up for their future emissions by investing in forests, renewable energy or other carbon-cutting projects.

Before the coronavirus crisis unfolded, airlines pushed for average emissions in the years 2019 and 2020 to be used as the baseline by which future emissions would be judged.

However, with the disruption from the Covid-19 pandemic, this baseline looks set to be drastically lower than anticipated. Thus, if the scheme goes ahead without changes, Corsia’s future carbon targets will be much tougher than envisaged.