Among other concerns, the US military parade will produce as much pollution as created to heat 300 homes for a year

Donald Trump’s military parade this weekend will bring thousands of troops out to march, while dozens of tanks and armored personnel carriers roll down the streets and fighter jets hum overhead.

The event has prompted concern about rising autocracy in the US. It will also produce more than 2m kilograms of planet-heating pollution – equivalent to the amount created by producing of 67m plastic bags or by the energy used to power about 300 homes in one year, according to a review by the progressive thinktank Institute for Policy Studies and the Guardian.

The military parade is meant to celebrate the US army’s 250th anniversary on 14 June – which will also coincide with the president’s 79th birthday. It will feature 150 military vehicles including 60-ton tanks and armored fighting vehicles, and more than 50 helicopters and aircraft such as a Mustang fighter aircraft and a B-25 Mitchell bomber, which were both used widely during the second world war. These vehicles burn dozens or even hundreds of gallons of fuel per hour.