The Amazon rainforest is the world’s largest tropical forest. It’s home to 30 million people and hosts the largest concentration of biodiversity on the planet. It’s quenched by the largest river in the world. It holds upward of 140 billion metric tons of carbon. And right now, it’s burning.

Across its 550 million hectares (one hectare is about the size of two soccer fields), more than 74,000 fires have started in the Amazon this year to date, an 84 percent surge from the year before, according to Brazil’s National Institute for Space Research (INPE). Fires are a natural part of many ecosystems, but not in the Amazon, where they are an almost entirely human-caused phenomenon. Farmers use slash-and-burn tactics to clear forest areas for crops. Illegal loggers and miners set fires to cover their tracks. In several instances, they have ignited blazes to drive indigenous people off their land.

The fires in the Amazon have now been burning for more than two weeks. Their smoke has spread across Brazil and shrouded the country’s biggest cities. Locals posted photos of flames, soot-darkened skies, and blackened water on social media:

This is a glass of water filled with rain water in São Paulo, Brazil.

This was taken today. #PrayForTheAmazon pic.twitter.com/XlhxGMSJNH — Madreelefante (@madreelefante) August 22, 2019

While alarming, they’re not the only blazes shrouding huge swaths of land in smoke.

More than 9,000 people were evacuated as flames spread this week across Spain’s Canary Islands. Wildfires also ignited this week in Alaska. Denmark dispatched firefighters to Greenland to control fires burning close to population centers. Major wildfires have also burned through Siberia, and environmental activists expect them to set a new record for burn area in Russia by the end of the season.

Part of the reason for these recent fires is the heat. This past July was the hottest July on record. Many parts of Europe shattered heat records: France, Germany, Poland, Spain, the Czech Republic, the Netherlands, the United Kingdom. That heat dried out vegetation and left huge swaths of forests and grasslands primed to ignite.

As the climate changes, periods of extreme heat will get longer, more frequent, and more intense. Years of actively suppressing natural fires have allowed trees, grasses, and shrubs to accumulate at unnatural levels in many parts of the world. Deforestation has disrupted the natural water cycle in some regions, causing the remaining undergrowth to dry out. And as people build their homes closer to wildlands, the likelihood of setting off an inferno will only rise.

Make no mistake: Humans are worsening the devastation from wildfires. Here are some of the scenes of destruction around the world taken this month.

Greece

Spain

Turkey

Indonesia

France

Russia