Nick Palmer
Fri, 21 Mar 2008 17:42:26 -0700
Could Vorts look over the paragraph below and give me their opinion on it (also please check the maths). It is part of an article I am writing for our newspaper on sustainability. << Perhaps people do not realise how little environmental space we all share because there is a rather strange belief around which often comes out in anti-Green propaganda articles, particularly in relation to global warming, where the protagonists try to lead us to believe that we cannot possibly affect the environment of Earth because we're so puny and the earth is so large. These people must be mathematically illiterate. In the late 1960's people raised concerns about the growing population and scoffers at the time claimed that the entire world's population could squeeze onto the Isle of Wight (although this assumes just over one square foot each!), thus making the world then appear a pretty roomy place. I did the complementary calculation and discovered that if the global population then (3.6 billion) was evenly distributed over of the land surface of earth, then each person would only have an area of land 220 yards square as their personal environmental space! Obviously some of the land would be hostile desert, ice fields, mountains, rainforest etc. The world suddenly looked rather cramped. I recently did similar calculations again, using the current world population figure of 6.6 billion, and our current personal environmental land space is now down to 150 metres square (164 yards square) per person. I then went on to calculate what size our personal spaceship is today within which we metaphorically have to live our lives, use energy, manufacture goods, dispose of waste, extract minerals, grow food, catch fish and dissipate pollution, pesticides etc within. Surprisingly, our personal spaceship works out to be a globe only about 1.18 kilometres in diameter within which we have a piece of Earth's surface about 277 metres square (of which 70% would be ocean). Perhaps this helps to make it clear why the total number of people multiplied by their individual impacts on the planet has now brought us to the point where we can put up a "House full" notice on planet Earth. >> The figures etc I used are easily findable. Radius of Earth = 3960 miles Surface area of sphere = 4pi x r squared Proportions of land compared to ocean 30%/70% Column of atmosphere above us, assuming pressure of one atmosphere to the top, 10.6km. (worked out using sea level pressure and density) Volume of personal spaceship's atmosphere = 10,600m x 277 x 277 cu metre Radius of personal spaceship = cube root of (Volume divided by pi x 3/4) I assumed that the spaceship should have constant atmospheric pressure throughout (as it would in space) to make things simpler to visualise because any gaseous pollutant introduced within the body of gas would reach roughly the same relative concentration to other gas molecules whatever the pressure; that is to say that one gallons worth of fossil fuel fumes would expand to a much greater volume high in Earth's atmosphere but the relative concentration would stay approximately the same. Nick Palmer