Climate Change

Climate change, previously known as global warming, is arguably the biggest modern threat to our human existence here on earth.

What do we know?

• The vast majority of scientists are in agreement that climate change is happening, and is caused by human activity (these are called anthropogenic causes).
• The main concern is not only the extent of change, but the rate of change, or how quickly it’s happening.
• Climate change deniers often dispute the science by saying that some areas are seeing colder temperatures and/or increased snowstorms. There are two responses to this:
  • (1) There is a massive difference in weather versus climate – weather is isolated events whereas climate is weather patterns over time – in other words, we can have colder weather events while the climate as a whole is still warming, and
  • (2) Changing the name from global warming to climate change represents the current reality better – climate change does not necessarily mean an immediate warming climate everywhere but rather rapid, extreme changes in storms, sea level, sea salinity, ice caps, permafrost, desertification, etc.

One of the key concepts to understanding climate change is the concept of positive feedback cycles and thresholds. In short, a positive feedback cycle is a system that is self-reinforcing. In the context of climate change, warming temperatures in the Arctic circle lead to permafrost melting, which releases more CO2 and other greenhouse gases, further warming the atmosphere, melting more permafrost, releasing more CO2, and so on. The concept of thresholds also means that at a certain point, a “tipping point” is reached, where all of these systems rapidly change at a rate we are unable to control.