Environment: Following the flows

Introduction

The scientific theory of plate tectonics suggests that at least some of these Arctic lands were once tropical. Since then the continents have moved and ice has changed the landscape. This unit will concentrate on evidence from the last 800,000 years using information collected from ice cores from Greenland and Antarctica, and will use this evidence to discuss current and possible future climate. The cores show that there have been nine periods in the recent past when large areas of the Earth were covered by ice. During the last 10,000 years – called the Holocene – there has been an unusually stable climate compared with the rest of the record, and the Holocene encompasses the entire development of human civilisation.

The Arctic, like any region, has always undergone climate change but there is evidence, for example in the decreasing sea ice cover, that suggests that the changes are happening faster. I intend to show how evidence from the ice cores suggests that flows of chemicals and energy dominate natural systems and cause these changes. I will discuss flows of water, heat and even pollution around the planet and show how, through positive feedback processes, the flows that are affecting the Arctic are already changing the whole planet. There will be further changes, with an impact on us all. The Arctic is often considered a victim of climate change – and it certainly is – but I hope to show that Sheila Watt-Cloutier was also right when she described the Arctic as a planetary barometer.

To discover the evidence that the Earth is dominated by flows I will start with that most famous Arctic animal of all – the polar bear.

This unit is an adapted extract from the Open University course Environment: journeys through a changing world (U116). [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)]