A man wearing a protective face mask walks past traditional large puppet figures called “Ondel-ondel”, also donning face masks and displayed along a sidewalk of a main road, as coronavirus disease (COVID-19) cases surge in Jakarta, Indonesia, June 30, 2021. (Photo by Willy Kurniawan/Reuters)

Commuters wear protective face masks as they walk through a subway station, in Sao Paulo, Brazil, Wednesday, December 1, 2021, amid the COVID-19 pandemic. Brazil joined the widening circle of countries to report cases of the omicron variant. (Photo by Andre Penner/AP Photo)

A pheasant stands in snow near Dulverton on January 30, 2012 on Exmoor, England. After unseasonably mild winter weather, some parts of the UK woke to a covering of snow as a cold spell of weather sets in, with forecasters warning temperatures are set to plunge as the week progresses. (Photo by Matt Cardy/Getty Images)

“Contrails (short for “condensation trails”) or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets or, if the air is cold enough, tiny ice crystals”. – Wikipedia

Photo: An airplane leaves a vapor trail as it flies in front of he moon on January 17, 2007 above Hanover, Germany. (Photo by Alexander Hassenstein/Getty Images)

Visitors watch as Grigory Broverman, a member of the Cryophile winter swimmers club, pours a bucket of cold water over his 6-year-old daughter Liza during a flash mob, part of a celebration of Polar Bear Day at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia, November 29, 2015. The air temperature was around minus 5 degrees Celsius. (Photo by Ilya Naymushin/Reuters)

A woman wearing leggings with the colours of the US flag walks along a street of Havana on February 18, 2015. President Barack Obama announced Thursday he will make a landmark visit to Cuba on March 21-22, pledging to address human rights as America pursues a historic thaw with its former Cold War foe. (Photo by Yamil Lage/AFP Photo)

A man uses a snow blower to clear a sidewalk during a winter storm ahead of the Christmas Holiday outside the Union Station, in Chicago on December 22, 2022. More than 2,200 flights were canceled across the United States by Thursday afternoon as a massive winter storm named Elliot upended holiday travel plans with a triple threat of heavy snow, howling winds and bitter cold (Photo by Kamil Krzaczynski/AFP Photo)

Vendor Yegor Dyachkovsky, 45, poses for a picture at an open-air market on a frosty day in Yakutsk, Russia, January 15, 2023. Yakutsk, one of the Russia's north-most cities, is hit by an extreme cold snap as the air temperature on Sunday (January 15) plunged as low as minus 51 degrees Celsius (minus 59.8 degrees Fahrenheit). (Photo by Roman Kutukov/Reuters)