#deforestation #feedback loops #Methane #sea level rise #terminology #tipping points
Doug Fogelson
Ever since the Industrial Revolution greatly increased emissions, all the following Greenhouse Gases generally remain active in the atmosphere as they accumulate. Today there is a clear call to action to limit the warming Earth below 2C degrees beyond pre-industrial levels (circa. 1850 to 1900). Accumulated carbon stored the atmosphere including all emissions occurring today propel warming conditions toward a cascade of existential “tipping points”.
Melting permafrost is one way that the warming climate can ramp-up due to a feedback loop. When permafrost melts, it releases naturally-occurring “trapped” methane gas that has been stored in the ground for thousands of years. Methane is a strong greenhouse gas — many times more destructive than carbon is to the atmosphere, so the permafrost release would induce a steep rise in global warming. Turning global temperatures down or somehow covering thousands of miles of permafrost with protection are very difficult (or impossible). We can however reduce current inputs of Methane in many ways today. One example is switching to electrical heating and stoves/ovens, with energy powered by renewable sources.
Glaciers melting due to warming temperatures not only adds to sea level rise, they also increase the amount of surface area that absorbs strong solar radiation onto Earth (intact ice sheets reflect it back out). The melting ice influences the flow of ocean currents which fuels further temperature increases that in turn continue to speed up the melting of more glaciers in a massive feedback loop. Displacement of people living on the coasts is a direct factor of sea level rise.
Deforestation–as seen in the Amazon and most other biodiverse areas–often to claim space for agriculture or cash crops, or due to massive forest fires (“feedback” of a warmer and drier planet), speeds up Earth’s heating. Our warming world reduces viable habitat on land and in the oceans and disrupts the food chain. It is not easy for animals to simply move to other locations with the warming temps, living systems have evolved with very specialized habitat and once these are impacted too far we begin to see extinction.
Understanding feedback loops and tipping points requires each of us to be thankful for what we currently enjoy. Importantly they act as a reminder to practice self-care and to help our Earth by becoming transformative Environmental Leaders at this critical juncture.
According to EarthHow, which of these is an example of a positive feedback loop?