The scale of the explosion that devastated Lebanon’s capital could be difficult for anyone to comprehend.
Videos of the blast, which has killed at least 137 people and injured more than 5,000, have been widely shared on social media and show a mushroom cloud propelling into the skyline.
Dozens of others are still missing.
Damage has been reported over six miles away from the site of the explosion with an estimated 300,000 left homeless.
In order to help contextualise the size of the disaster, a professional cartographer has created maps comparing the blast radius of the explosion as if it had happened in London or New York.
Joanna Merson, a cartographic developer at the University of Oregon, shared the comparisons on Twitter.
Merson’s maps show three rings representing different levels of damage: everything in the 1km radius of the blast has suffered widespread destruction; most structures in the 5km ring have sustained heavy damage; and the 10km showing how far the damage has been reported.
1/x This morning I woke up to see viral maps incorrectly comparing the damage area of the Beirut explosion to London and New York. I have corrected the maps with a little thread to explain my corrections. img 1. tweet with my notes. img 2-4. my new maps. pic.twitter.com/nz9Q1X0wLt— Joanna Merson (@JoannaMerson) August 5, 2020
It is impossible to accurately state whether the levels of destruction are comparable with London and New York. For example, the significant number of densely packed, high rise buildings in both cities could have cushioned the blow and reduced the spread. Similarly, the explosion would likely have caused more damage in London due to a large amount of the blast radius in Beirut being absorbed by the Mediterranean sea.
However, had the explosion happened in central London it is possible the House of Commons, Buckingham Palace and Westminster Abbey would have all been caught in the blast.
Most of the City of London, in theory, would fall within the same radius as well as areas as far as Hampstead Heath and Norbury.
Merson explained she avoided using Google Maps due to the images being projected in Web Mercator, which stretches the earth to make it look like a square.
This is done because it is impossible to make the spherical earth appear perfectly in proportion on a flat image.
4/x I picked the 10km radius by measuring the distance to the airport runways in the original map. The circles ignore all topography, while it looks like the actual damage stretched farther along the coastline and not as far inland, uphill(?).— Joanna Merson (@JoannaMerson) August 5, 2020
She also notes her maps fail to account for topography, noting “it looks like the actual damage stretched farther along the coastline and not as far inland, uphill?”
Merson emphasised her maps did not model what the damage would have been to other cities, they were just there to help visualise the scale of explosion and the wreckage it caused.
5/x If you made it this far, you may already have noticed, my maps use azimuthal equidistant projections, centered on each POI, and are displayed in the same scale, so they can be compared. BECAUSE SCALE AND PROJECTIONS MATTER. Enjoy.— Joanna Merson (@JoannaMerson) August 5, 2020
If the blast had occurred in New York the roughly six-mile radius of damage would have reached as far as The Bronx and likely flattened Wall Street.
The explosion in Beirut was preceded by a large fire at the Port of Beirut, which caused the roof of a warehouse which had 2,750 tonnes of ammonium nitrate inside to set on fire.
After a series of smaller blasts, a colossal explosion happened around 18:00 local time, creating a mushroom cloud over the city.
Experts from the University of Sheffield said the explosion was “unquestionably one of the largest non-nuclear blasts in history.”
They predicted the explosion was equivalent to 1,000 to 1,500 tonnes of TNT, which is thought to be about a tenth of the intensity of the Hiroshima atomic bomb.
Ammonium nitrate is a crystal-like white solid commonly used for fertilisers.
It can be combined with fuel oil to become explosive and it has been used as a weapon in the past.
The explosion comes at a difficult time for Lebanon as the country struggles to control coronavirus and is suffering from the longest economic downturn in decades.
There has been widespread anger at the government in recent years and has faced accusations of corruption and neglect from the public.
On Wednesday the government put a number of port officials under arrest as it investigated the explosion.