If Man can have a negative effect on the climate, perhaps he can also have a positive effect on it. This is the starting point of bioengineering which usually involves large scale futuristic projects that directly want to change our planet.
A space sunshade for the Earth – or, more exactly, billions of lenses or tiny metal screens to deviate some of the sun’s rays – was suggested. Indeed, reducing the contribution of sunbeams by 2% would compensate global warming by 2100.
A volcanic eruption reduced the terrestrial temperature by 1.5% in 1991 after severe sulphur emissions. Some people wanted to do this again with sulphur and other particles. However, sending sulphur – a very reactive product – into the upper atmosphere causes problems. Clouds of sea water could produce the same effect but one would have to project 10 000 litres of water a second to form enough clouds to compensate global warming.
Feeding phytoplankton with iron sulphates or nitrogen fertilisers could increase the amount of CO2 captured by oceans. This is the only bioengineering solution for which exterior testing is carried out. But the results are disappointing. Some studies show that this addition will increase the number of phytoplankton by 30. These will thus absorb more CO2, but in the end, very little CO2 is stored.
Those who see these ideas as ways of playing God fear the solution may be worse than the problem because directly changing our planet could have unpredictable secondary effects. Such action is part of an “engineer” viewpoint that considers the environment as artificial rather than restoring the existing natural balance.