Systems Thinking Through Climate Change — 5 Positive Feedback Loops
By: Econsystems Thinking
Tags: Renewable Energy, Ocean Acidification, Systems Thinking, Climate, Climate Change

So far most of my systems have been pretty simple so I thought I’d try something with a few more moving parts. I think this falls under my domain since I remember reading that we shouldn’t do anything about climate change because of the economy. Carbon emissions are an externality, a cost to be paid by all of the world’s citizens as opposed to the producers and consumers. The lack of response is not due to a lack of technical knowledge, but a lack of political will or more candidly an unjust distribution of power.

Originally I made one more all encompassing systems map, but I later realized that some of the positive feedback loops that emerged deserved a separate explanation. These aren’t new, but it was certainly interesting to see how they fit together. I’ll note beforehand it is possible to sort of reduce greenhouse gases, radiative forcing, and global temperature to basically the same thing, but I think the distinctions are important here for reasons I’ll explain. Remember dotted lines indicate a negative relationship.

Dotted Lines = Inverse

First some definitions so we’re all on the same page.

Radiative Forcing here represents the energy imbalance of Earth. When there is an imbalance in energy, the earth’s temperature slowly rises (or falls) until equilibrium is reached. Since this takes a long time there is a delay as you can see. (The double lines)

Albedo (reflectivity of Earth’s surface) prevents energy from being absorbed, so more albedo means lower radiative forcing. Greenhouse gases prevent energy from going out so more greenhouse gases means more radiative forcing.

First Reinforcing Feedback Loop (R1): Radiative forcing raises temperatures, which reduces ice. Ice is white, and sea water is a much darker, more absorbent color. When there is less ice, there is less albedo, which increases radiative forcing, and the cycle continues.

Second Reinforcing Feedback Loop (R2): Higher temperatures lead to permafrost melt which leads to more greenhouse gases, higher radiative forcing higher temperatures and so on.

Third Reinforcing Feedback Loop (R3): Wildfires, which here could functionally be replaced with desertification and rainforest drying which can release large amounts of CO2, and take in less CO2 as time goes on. These could represent R5 and R6, but they would feel redundant to me since the mechanism of action is the same. Heat can negatively effect plant life which ultimately leads to higher GHG concentrations.

Fourth Reinforcing Feedback Loop (R4): This one is the hardest to explain since the mechanism isn’t as well known. It is one of the least understood potential positive feedback loops due to the contradicting effects of clouds on climate. What makes this a potential positive feedback loop is that when acidification rises it can actually have a negative effect on albedo. This loop is one of the reasons why the distinction between Greenhouse Gases and radiative forcing is so important. More greenhouse gases lead to ocean acidification while positive radiative forcing and climate change in isolation do not.

From Nature.com “Acidification would lead certain marine organisms to emit less of the sulphur compounds that help to seed the formation of clouds and so keep the planet cool.” Clouds reflect sunlight, particularly when lower in altitude. Clouds are composed partially of compounds released by marine life.

SO… greenhouse gases lead to ocean acidification which reduces albedo, which increases radiative forcing, which increases global temperature, which increases permafrost melting, which increases greenhouse gases and we start all over again.

Fifth Reinforcing Feedback Loop (R5): Heat waves lead to less ice which reduces albedo which increases radiative forcing which increases global temperatures which increases the frequency and severity of heat waves.