As you have seen, the RCP8.5 scenario suggests a temperature increase of between 5°C to 10°C in the Arctic by the end of the century. This will lead to the warming of Arctic waters and the melting of the tundra and sea ice. Watch the video below to see how warming over the past 30 years has affected the extent of Arctic sea ice coverage.

Polar ice plays a vital role in the climate system due to its albedo. As the ice melts, less solar radiation is reflected into the atmosphere. This leads to increased temperature which then creates more ice melt. This is an example of a positive feedback loop in which a disturbance, in this case increasing temperature, results in an amplification of that disturbance (see Lesson 7). It is because of this feedback loop that the Arctic warms more quickly than other areas of the globe.

As it did during the PETM, the Earth will survive these climactic changes. Our concern is the implications that these changes will have for human civilization as we know it.