The main church in the town of San Damian Texoloc, Mexico stands in front of the Popocatepetl volcano as is spews ash and vapor early Tuesday, July 9, 2013. Last Saturday, Mexico's National Center for Disaster Prevention raised the volcano alert from Stage 2 Yellow to Stage 3 Yellow, the final step before a Red alert, when possible evacuations could be ordered after the Popocatepetl volcano spit out a cloud of ash and vapor 2 miles (3 kilometers) high over several days of eruptions. (Photo by J. Guadalupe Perez/AP Photo)

Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. In this artwork, Liu wants to express his concerns about China and its people, including air pollution problem, Liu told Reuters. (Photo by Kim Kyung-Hoon/Reuters)

General view of Chilean Calbuco volcano from Puerto Montt, located at 1000 km southern Santiago de Chile, Chile, 22 April 2015. Due to the eruption of the volcano with a smoke column 20 km high, authorities declared a red alert and ordered the evacuation of around 1500 inhabitants of Ensenada, Alerce, Colonia Río Sur and Correntoso towns. (Photo by Alex Vidal Brecas/EPA)

Revellers hit the town on Saturday, February 19, 2022 for a pub crawl despite the snow in Leeds, United Kingdom. The UK capital was placed under its first ever “red” weather warning, meaning there is “danger to life”. The same level of alert was in place across southern England and South Wales, where schools were closed and transport paralysed. (Photo by Nb press ltd)

A woman carries an umbrella during a heat wave in Rome, Italy, 16 July 2023. Italy is facing the third heatwave of the summer on 16 July bringing record temperatures. The new heatwave is forecast to peak on 18 July, when temperatures in areas of southern Sardinian may reach 48 degrees Celsius, according to forecasts. On 15 July, the health ministry has put on red alert major Italian cities. (Photo by Massimo Percossi/EPA)

A girl runs as she plays in a fountain at a shopping mall in Beijing, Friday, June 23, 2023. Authorities issued a rare red alert for high temperatures in parts of China's capital on Friday, the highest level of warning, as highs were expected to once again climb to around 40 degrees Celsius (104 degrees Farenheit). (Photo by Mark Schiefelbein/AP Photo)

A woman tries to hold an umbrella amidst gusty winds as Cyclone Michaug is expected to make landfall on the eastern Indian coast, at Foreshore Estate Beach, in Chennai, India, 03 December 2023. The Indian Meteorological Department has issued a red alert for heavy rains in Chennai as the cyclonic storm, “Cyclone Michaung” is anticipated to make landfall between Andhra Pradesh's Nellore and Machilipatnam on December 05. (Photo by Idrees Mohammed/EPA/EFE)

A Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)