2016 was a notoriously bad year. It seemed that in order to cope, everyone just hunkered down and decided to live in their own personal bubble. It also seemed as if a toxic haze had enveloped the Earth and just wouldn't go away. Well, according to a recently accepted article in Geophysical Research Letters, that is exactly what happened. A thick layer of hydrogen cyanide in the stratosphere was hovering over all of our heads the whole year and still hasn't gone away (a la Trump)!
To be fair, there's always a very little bit of hydrogen cyanide floating around up there. But in 2016, stratospheric hydrogen cyanide levels were on the order of 50-90% greater than normal.
How did it get there? Well, the 2015 fire season in Indonesia (yes, they have a "fire" season) peaked that year in September-October. The seasonal fires are typically set on purpose to clear peat land (which apparently releases oodles of hydrogen cyanide when burnt) in order to use the land for industrial agriculture; and in 2015 the fires were more difficult to extinguish due to drought conditions.
So, that's really it! A month or two of fire in an equatorial island nation, caused an extreme global increase in hydrogen cyanide in the stratosphere for well over a year. According to the lead author, as of April 2017, hydrogen cyanide levels have still not returned to normal.
Still think that humans have no effect on the atmosphere? Then you're likely living in a bubble. And not the good kind of bubble, like the bubble that's made out of pie that you're "forced" to eat your way out of. I want to live in a pie bubble.