Other ways to enhance the Earth’s Albedo...

Hi all,

The last post looked at the effects on enhancing the albedo of the earth...however, this is limited to only enhancing the albedo of marine stratiform clouds. This got me thinking about what would be the impact if we increased the albedo of other regions e.g. urban areas and crops

Akbari, et al. (2009) found that by increasing the albedo of urban areas, this could, to some extent, counteract the warming induced by GHG emissions, by increasing the concentration of solar radiation reflected. Through using reflective materials in replace of roofs and pavements (that together make up 60% of urban surfaces) the albedo of urban areas could be increased by 0.1. This would be equivalent to offsetting 44Gt of C02 emissions. At $25 a tonne, this could potentially save $1,100 billion dollars just by changing the albedo of roofs and pavements.

Crops exert an important influence over the climate energy budget because of their difference in albedo compared to soils and natural vegetation. Therefore, one idea proposed is to bio-geoengineer  crops by having specific leaf glossiness to ensure maximum solar reflectance. Ridgwell, et al., (2009) estimates by doing this, temperatures can be reduce by 1°C during summer for much of Central America, if the bio-geoengineered crops are adopted.

Enhancing the albedo of regions will not cause significant changes in temperature, unlike other Geoengineering options, but it will provide society with more time to advance the development and use of low–emission energy and conversion technologies (Hamwey, 2006). Personally, the idea of bio-geoengineering crops sounds a bit scary, as these crops will be then eaten by people, but genetically modifying crops is an idea that has been debated for years, research into whether crops could be modified further could be interesting...However, the idea of increasing the albedo of roofs and pavements does seem more viable...if roofs and pavements were replaced gradually with more reflective material then this could buy us more time, with relatively little inconvenience. Moreover, it would likely cause significant changes to temperatures locally, reducing the urban heat island effect. Overall, it could be a very small step to mitigating global climate change...or would it be an excuse to relax regulations on emissions? To do or not to do...that is the question!