The Lost World of the Arctic
|A Warm Arctic||Climate Change||Polar Light Regime||Paleo-Arctic Forests||Paleo-Arctic Fauna|
A Warm Arctic
The polar regions are at the cold extreme of the equator-to-pole temperature gradient. When the Earth's global mean surface temperature goes up or down, as it has many times in the past, those changes are expressed most strongly at the poles. This phenomenon is known as 'polar amplification' (e.g. Lee, 2014). Polar environments are therefore a very sensitive indicator of global climate change.
At the present time the Arctic region is the largest area on the planet exhibiting the fastest rate of warming (IPCC, 2013). It is warming faster than Antarctica because the Antarctic continent is covered by a large ice sheet that in places is many kilometers thick. This large ice mass takes a lot of energy to melt. The Arctic region, by contrast, is mostly an ocean upon which floats a relatively thin layer of sea ice that melts much more easily. Once that ice is gone the Arctic is likely to warm even more rapidly.
For most of the last 500 million years the Earth's surface temperature has been higher than it is now and the Arctic has been largely ice-free. For the period of time that is the focus of this interactive catalogue the Arctic was covered in forests that supported an abundance of animal life including a variety of large and small dinosaurs, marsupial and placental mammals, birds, and a wide range of invertebrates. All these organisms lived close to the ancient North Pole where, like today, the winter was a time of permanent darkness lasting several months, but during the summers the sun never set (Herman and Spicer, 2016).
This extinct ecosystem was highly productive and has resulted in huge amounts of coal being formed and preserved in Arctic rocks . This tells us it was a highly efficient natural system for capturing and storing carbon from the atmosphere. There is nothing like it on Earth today, but if the story of global warming plays out as most scientists think it will, then a time will come in the next few centuries when forests can again flourish in the high Arctic where today there is only tundra and ice desert.
This site documents some of the evidence that allows us to reconstruct that ancient extinct ecosystem in great detail over an interval of time that is often refered to as a natural 'greenhouse climate'. In many ways it is not just a record of the past but a blueprint for the future.
|Melting sea ice off the northern coast of Alaska, approximately 70°N. Photograph taken in the summer of 1978.|
|Reconstruction of a 70 million year old (Maastrichtian) forest that existed in northern Alaska when it was at a latitude of between 80 and 85 °N. Hadrosaurs roam through a seasonally deciduous conifer-dominated forest under almost permanant low cloud cover.|