On February 8th 2024, NASA launched a satellite named PACE into space. It is supposed to investigate the role of aerosols in the climate.
Small things can have big effects, the oceans are filled by a tiny plankton. Through a procedure, they produce a chemical called dimethyl sulfide(DMS). This chemical produces what people refer to as the smell of the sea. When DSM evaporates from sea level through some chemical reactions they produce sulfur aerosols. These aerosols then eventually nest water vapors. The vapors eventually form the clouds. The clouds are a crucial part of life on the planet earth. They bring water from the oceans into the lands. Clouds also reflect parts of sunlight, cooling down the earth. This is the same process that thermal geoengineering proposes to cancel out the warming effect of greenhouse gasses.
Until recently, the ship fuels were extremely unrefined and contained high degrees of sulfur, the smoke from ship funnels emitted sulfur particles. These particles then form a series of clouds, which is called “ship tracks”. Ship tracks are visible in satellite images and indicate the trajectory of ships movements. Because sulfur is toxic, in 2020, the International Maritime Organization put a limit on the sulfur content of the ship fuels. This new law is controversial among climatologists. Some climatologists believe that the sulfur content in ship fuels had a positive effect as they helped formation of clouds which reflected the sunlight out of earth. Some of them even cite this law as the main contributor to 2023 hot weather. Others of course believe that the effect was not so big.
The effect of aerosols is that climate is the main source of uncertainty. This is what produces error bars in climate models and satellite PACE is supposed to make this clear. It is equipped with cameras that are capable of tracking both particles on oceans (namely Planktons) and aerosols in the atmosphere.
Source: Economist
