Everyone is always looking for ‘big ideas’, the ones that will in one fail swoop solve all our problems. For me, the business of reducing our CO2 emissions and looking after the environment takes a different approach: we mustn’t stop looking for the ‘big idea’, or even several of them, but in the meantime we shouldn’t ignore the myriad of smaller ideas that on their own can’t turn everything around, but that definitely can help stop the rot.

This is why I love the latest idea put forward by Hasham Akbari, a scientist based at the Lawrence Berkeley National Laboratory in California. It’s really simple: if we turn more of the landscape, and above all the cityscape, white, more sunlight will be reflected and this will help reduce CO2 emissions and delay the effects of global warming.

So what we need to do is to emulate the inhabitants of many a sun-drenched country, and paint all possible outdoor surfaces (above all the roofs of all buildings) white, or at least a light-reflecting colour. This approach will contribute to the reduction of global warming in two ways:

  1. Sunlight reflected back from the earth’s surface reduces the amount of thermal energy given off, and thermal energy contributes to the greenhouse effect. Therefore, if we increase the surface area that reflects sunlight, we reduce the thermal energy given off by the earth.
  2. Buildings that reflect sunlight become less hot in the sun, and therefore need less cooling down. This concept has already been understood in places like California, where whitehouses with flat roofs have been painted white since 2005 in order to reduce the need for power-hungry, CO2 emissions-generating air conditioning.

Akbari reckons that if we all get together to paint an additional 0.3 percent of the earth’s surface white (or at least a colour that reflects sunlight), we could actually save 44 billion tonnes of CO2 emissions, the same as the expected rise in emissions over the next 10 years, giving us more time to work on other long-term ‘big ideas’.

Perhaps painting 0.3 percent of the earth’s surface white is a little too much to hope for, and to achieve it, we would certainly have to address several major issues, starting with the fact that white sloping roofs would be, quite frankly, ugly, let alone a potential navigational nightmare for air traffic (hold on, maybe this is a cunning plan to reduce air traffic… keep that thought!). This would certainly be the case for white roads.

However, it does remain an excellent idea, and everyone could contribute to it cheaply and quickly. Imagine, for instance, if we all went out this spring and painted just our patios and garden sheds white. This would already account for a huge surface area, and at least several million tonnes of CO2 emissions, and all for the cost of a pot of paint. Now, let’s take it further: imagine that governments decree that all playgrounds, outdoor carparks, warehouse roofs, the roofs of public buildings are painted white. What about if the roofs of all new cars have to be white? Ok, that’s a contradiction, but could theoretically reduce the emissions of all future transport…

I think this idea has mileage, and will be off tomorrow to B&Q to buy my pot of paint. Not sure what I’m going to paint yet, but here’s advance warning to the neighbours…