|Our Faustian bargain: the byproduct of burning dirty
fossil fuels are short-lived atmospheric aerosols
which provide temporary cooling
The climate system will heat well past 1.5 degrees Celsius (°C) and perhaps up to 2°C without any further fossil fuel emissions. That’s the conclusion to be drawn from new research which should also help demystify the rhetoric from the 2015 Paris climate talks of keeping warming to below 1.5°C .
It’s not that 1.5°C isn’t dangerous: in fact, at just 1–1.1°C of warming to date, climate change is already dangerous. A safe climate would be well below the present level of warming, unless you think it is OK to destroy the Arctic ecosystem, tip West West Antarctic glaciers into a self-accelerating melt, and lose the world’s coral reefs, just for starters.
The new research quantifies the effect of losing the very temporary planetary cooling provided by atmospheric aerosols.
Aerosols (including black-carbon soot, organic carbon, sulphates and nitrates and dust) are very short-lived particles in the atmosphere that have a cooling impact that lasts around a week. Most of these aerosols are anthropogenic, that is produced by human activity, and most of the anthropogenic aerosols are a byproduct of the extraction and burning of fossil fuels. Perhaps best known are the polluting sulphates and nitrates from coal-fired power stations, that combine with water molecules in the atmosphere to produce what is popularly known as “acid rain”.
The problem is our “Faustian bargain”: these aerosols are keeping the planet cooler than it would otherwise be, but are coming from burning fossil fuels that pour carbon dioxide (CO2) into the atmosphere, heating the planet for centuries to come. The absolutely essential moves to eliminate fossil fuel emissions will also cut the cooling aerosol impact; the net effect will push the planet towards very dangerous warming conditions.