| John Hiemstra Blog Entry |
Personal ProfileName: John Hiemstra Age: 39 Location: Swansea Job: Lecturer in Physical Geography University: Swansea University Education: (Dutch equivalent of) A-levels in Maths, Physics, Chemistry MSc in Physical Geography (University of Amsterdam) PhD in Physical Geography (University of Amsterdam) Date: 9th May 2007 Time:8:34pm Location: Home Title: Mud - only handy when it comes to slingin’ it? As a lecturer at Swansea University, I lecture students. No surprise there. I teach topics that relate to geology and the ‘physical side’ of geography, notably about the physical processes that play a role in shaping the earth’s surface. What I also do is research. In fact, the research part of my job is just as important as the teaching part. It involves studies of landforms and sediments that have been formed by, or are associated with, glacier ice. For fieldwork I have travelled to some of the most remote places of the world, such as Iceland and Antarctica, where glaciers and ice sheets still exist - Do you feel sorry for me already…? - but also to places closer to home, such as the Gower Peninsula and the Brecon Beacons, which have experienced ‘icy’ conditions (were glaciated) during the Last Glacial Maximum, c. 20,000 years ago. What I try to do in all these places is investigate how and to what extent glaciers and large ice sheets change the landscape. We all know that moving ice erodes (takes away) material in some places and builds (deposits) new landforms in others. Examples of erosion can be seen in Norway where glaciers have carved out deep U-shaped troughs (fjords), whereas moraine ridges, which are very common throughout the UK, are good examples of landforms deposited by glacier ice. By studying formerly glaciated landscapes and by investigating the sediments that have been deposited, physical geographers are able to reconstruct dimensions of past glaciers (size and thickness) and to get an idea about ‘glacier dynamics’ (the growing and shrinking behaviour through time). Why do we want to know, I hear you say. Why would one want to dig in mud, sand and gravel to learn about glaciers that once were? The answer is simple really and has to do with an important principle that is applied in all earth sciences, including physical geography. This principle is ‘The past is the key to the future’, and means that if one wants to understand certain ‘earth system processes’ that operate now or in the future, the best thing to do is to look back. Obviously, where changes are slow, as in glacial systems, direct measurements are difficult to take, and ‘historical’ sedimentary records are often the main source of information. By studying glacier dynamics of the past, a record of which is kept in the ‘mud’ that is deposited by the ice, we can learn about future glacier dynamics, which can help us, for example, to make predictions about how the large present-day ice sheets of Greenland and Antarctica will behave in the near future. Don’t we all want to know whether these large bodies of ice will melt now that global temperatures are predicted to rise at least another few degrees C over the next century or so…? Are the Greenland and Antarctic ice masses relatively stable? Should we start worrying? Should we start thinking about moving to higher ground? The answer may be in the mud…. Want to know more? Send me a question. |
