G.C.S.E. GEOGRAPHY COURSEWORKAn example of a project

The new geography GCSE coursework has given headaches to many geographyteachers around the country. The vast range of the subject has meant that many teachershave had to become experts at many things overnight.

The title of my project Are we living in a greenhouse? raised the eyebrows of myteacher who was worried about the lack of information on the subject. I decided topersevere with the project, because the information I had read in newspapers and heardon the television was so contradictory that I really didn't understand what 'thegreenhouse effect' was, and I was determined to unravel the mystery of it.

I wrote to the Meteorological Office requesting information on the subject. Mr JohnFullwood replied, sending me a tremendous amount of data, but cautioning me that thesubject was a tricky one, and he warned me that it was an immense task. The informationhe sent me was highly complex, but after sitting down and reading it, the projectgradually began to take shape.

Basically, the greenhouse effect is when shortwave radiation from the Sun is re­radiated back out to space in the form of longwave radiation. Some of the longwaveradiation is 'bounced' back down to the Earth's surface by a blanket of water vapourmolecules and carbon dioxide gas. This layer of insulation warms the Earth's surfaceconsiderably. Normally, the global mean surface temperature would be - 18°C, but theeffect of insulation increases it to +15°C.

This part of the greenhouse effect is a part of the natural carbon cycle which isnecessary for life on Earth. The problem with the greenhouse effect is that man isreleasing more carbon dioxide into the atmosphere, by the burning of fossil fuels. He iscutting down the forests, which along with the oceans are vital for the absorption ofcarbon dioxide. This has resulted in a recorded increase of carbon dioxide levels of sevenper cent in the last thirty years.

Scientists have been using computers to simulate the effects of the greenhousetheory. The computer predictions of the greenhouse effect show two main 'fingerprints';these are uneven temperature changes and uneven rainfall level changes across theglobe.

The information I was sent included weather records from four sites across theglobe. I drew graphs of temperature and rainfall over a period of a hundred years. Byanalysing the graphs I was able to compare the results with the computer predictions. Idrew the conclusion that, although there definitely were climatic changes such as globalwarming and changing rainfall patterns, the results were not yet clear enough, and Iquestioned how accurate the computer predictions were.

This air of uncertainty around the greenhouse effect, the "is it?" or "isn't it?"mystery still seems to be intact, although in my opinion the greenhouse effect is justbeginning, and the 'fingerprints' will become more apparent over the next few decades.

Hilton, KATIE DAYHuntingdon

CORRECTIONIn the advertisement for marine meteorological forecasters (Weather, July 1989,

p.317) the P.O. Box number should read 8658, Doha, Qatar.

AVAILABLECopies of the Quarterly Journal ofthe Royal Meteorological Society from volume

74 (1948) to volume 102 (1976), virtually complete, unbound but boxed, are available- preferably to an educational institution - for a nominal sum (payable as a gift to charity)plus removal arrangements. Contact Dr Ian Ashwell, 25 Parkside, Vanbrugh Fields,Blackheath, London SE3 7QG (Tel: 01-858-0093).

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