An underground fire in southwestern China has been burning steadily for 59 years and counting.
Video by CCTV+
There’s a patch of land in a village in Chongqing, China, with an area of about 4 square meters, where a fire has burned for the last six decades. The fire keeps burning all year round, no matter the weather, and reignites even after water has been poured over it. At any given time, you’d see about seven or eight flames dancing out from under the surface.
While certainly remarkable, underground fires can be found across the globe. There are similar fires in the US as well as in Russia, in a range of temperatures and weathers. China by itself has 62 such fires scattered across its northern region.
What, therefore, causes such fires? In China, for example, coal is generally the fuel that keeps these fires burning. These fires can be started by natural processes, though they can be intensified by human actions like coal mining.
An underground coal mine fire in Jharia, India [Photo by Johnny Haglund]
When coal is exposed to oxygen, a heat-producing chemical reaction occurs. This process can take years to build up, even in lower temperatures. When the fire starts, it moves downward into the ground and sets the air in the spaces between rocks and grains of dirt alight. These fires can burn for a long time, and can even burn underground without anyone on the surface knowing.
The fire in Chongqing in particular had a man-made origin. 59 years ago, oil exploration efforts began on the site. The oil exploration team drilled a natural gas well, which has been producing gas and keeping the fires burning since then. These flames, which started decades ago, are still the same ones burning now.
People living around the decades-old fire have found ways to make the most of it. They usually make two trips a day to the site to boil water, which only takes just about five minutes. They have also found ways to use the flames for cooking. Other communities around the world living close to such fires have done similar things.
Now, this may seem like these underground fires are harmless, even beneficial. To a certain extent, they can benefit the communities living around them. However, there are downsides to these fires that far outweigh these benefits.
Fumes come out of cracks on the ground outside Jharia [Photo by Johnny Haglund]
The impact of these underground fires can be quite significant. Underground fires, depending on how extensive they’ve become, can cause sinkholes. The land can collapse into itself because the fires have consumed the coal under the surface, thus increasing pressure on the soil. Once this happens, more oxygen gets sucked into the ground, giving the fires more fuel.
Even though sinkholes don’t form, cracks can also appear on the surface. The smoke emitted by the underground fires can go through those cracks, exposing people on the surface to a toxic cocktail of carbon monoxide, sulfur dioxide, as well as coal dust.
If all of that sounds menacing, that’s probably because it is. This combination is not only bad for people’s health, but it can also contribute more greenhouse gases to the atmosphere. An underground fire, therefore, can also make climate change worse.
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