Physics

We investigated the effect of pollution on the albedo (reflectiveness) of water, suspecting that it would cause the albedo to decrease very slightly. This would be significant in terms of the greenhouse effect, because a decrease in earth's albedo would cause less radiation emitted from the sun to be reflected off the surface and more to be absorbed by earth. While UV radiation reflected off the earth will pass through the greenhouse gases in the atmosphere, the radiation that is absorbed will be emitted as infrared radiation. This can be absorbed by greenhouse gases, causing some to be re-emitted into the atmosphere, contributing to global warming. Although it is on a small scale, our findings could indicate a general trend.

Using a light probe, we measured the 'lux' (light intensity) of the ground before comparing it to that of a water sample. This was an attempt to minimise the error related to fluctuations of natural light. The difference is how much more was reflected off the water than off the ground. We took four measurements of distilled water and lake water, finding an average for each, and a percentage uncertainty telling us how much the data from each sample differed.