What are examples of a positive feedback loop caused by climate change?

A positive feedback loop is a series of events that enhance or amplify changes in climate. An example of this in the context of global warming is the ice albedo feedback loop. Ice is a highly reflective surface (reflects approx. 50% of solar radiation) and is important in regulating temperature on Earth. Rising CO2 levels in the atmosphere causing global warming by enhancing the greenhouse effect mean that ice melts, and this leads to a decreased area of ice to reflect solar radiation back into space. A lower albedo means that more solar radiation is absorbed by the earth's surface, warming the surface and increasing ice melt. This leads again to decreased ice area and lower albedo. This leads to a positive feedback where ice continues to melt and the earth continues to warm.