Overview
What is Climate Change?
So the climate is changing... but why?
The cause of climate change can’t be traced to a single activity. Industrialization catalyzed the burning and use of fossil fuels in order to create the modern world today. When fossil fuels are burned, they release greenhouse gasses into the atmosphere. These greenhouse gasses act as a blanket to the earth, trapping heat inside the atmosphere.
Overview
Definition
Climate change is a wicked problem that refers to long-term shifts in temperatures and weather patterns caused by the increase in greenhouse gasses in the atmosphere.
Scientific Consensus
Climate change is not a myth or a conspiracy, but is backed by world experts. Accredited organizations around the globe show scientific evidence linking human activity to climate change.
Human Activity
The main driver of climate change is human activity. Humans have disrupted the earth's natural process of cycling greenhouse gasses by adding more into the atmosphere at a much higher rate than what would normally be released without human activity.
Plants and oceans are responsible for the majority of greenhouse gas absorption, and they are not able to keep up with the increased emissions from human activity.
Greenhouse Gas Effect
Since the 1950’s, the production rate of GHG emissions has surpassed the rate of environmental absorption (also known as sequestration). With this imbalance, the concentration of greenhouse gasses in the atmosphere has risen significantly. The increased concentration of GHGs in the atmosphere has led to an increase in the average surface temperature of the earth.
Energy created by the sun is absorbed from the earth’s surface and released back into the atmosphere as heat. As the heat travels through the atmosphere back out into space, GHGs absorb most of the heat. The greenhouse gasses then radiate this heat back onto the Earth's surface, to another greenhouse gas molecule, or out to space.
This is known as the greenhouse gas effect.
The excess GHG emissions heat the Earth like an oven. If serious changes to reduce emissions are not made, the damage can become irreversible past tipping points.
Tipping Point
In regard to climate change, a tipping point is the point where a sequence of small changes has accumulated, leading to long-term consequences that are difficult to reverse or restore back to a healthy state.
![Black and white see-saw](https://cdn.prod.website-files.com/63da85bd0e39561929afa031/63f3ae1781e44b504c32c2ff_Z7dpKa5mnM2bd-eV_de5A_G7fJbLWqJbl.png)
For example
If you were walking across a seesaw, once you edge slightly past the middle, the seesaw pivots the other direction, tipping the entire structure. Human activity is close to tipping the climate change seesaw.
Feedback Loops
Positive Feedback Loop
Ice in the Arctic Sea melts due to the earth’s rising surface temperature. With less sea ice available to reflect the sun and heat from the earth’s surface, the exposed ocean absorbs the heat. This leads to further warming, which causes more ice to melt, leaving even more ocean exposed to absorb the heat.
This type of cycle is called a positive feedback loop.
![Positive-Feedback-Loop.png](https://cdn.prod.website-files.com/63da85bd0e39561929afa031/63f3b21577e14762410a2caf_3yg9mOUZfCzyX80s_SgHKAng0ygVjTA-S.jpeg)
A positive feedback loop is a process or cycle that boosts the effect of change and produces a more unstable system.
Once enough of the Arctic ice is gone, the system could be pushed into a new state with a devastating effect on the global environmental system.
Negative Feedback Loop
In contrast, a negative feedback loop is one that lessens the effect of change and helps to keep balance within a system.
For example
The increase in earth’s temperature increases the cloud cover which helps reduce the effects of solar radiation and limits warming.