All hands have to be on deck if the world is going to tackle degradation, and one of the biggest emitters is also one of the least well known—international shipping. A 2018 study estimated that pollution emitted from cargo ships resulted in 400,000 annual premature deaths from lung cancer and heart disease. Many of those deaths resulted from the sulfur dioxide the ships were belching into the air. Since the beginning of the year, sulfur dioxide has been capped at .5% of emissions, compared to 3.5% previously. While the long term benefits of that emissions cap will take some time to appear, there's another pollutant that could potentially be tackled in the near future: nitrogen dioxide.