Bill Gates has invested at least $4.5 million of his own money on geoengineering projects since 2007, ScienceInsider blog has reported.

 

The world’s richest man has tipped cash into “the study of methods that could alter the stratosphere to reflect solar energy, techniques to filter carbon dioxide directly from the atmosphere, and brighten ocean clouds,” the blog said.

 

One project is the development of spray systems for marine clouds and another is aeronautics research related to altering the stratosphere.

 

But the Microsoft co-founder’s money has not funded any field experiments. Geoengineering is the concept of manipulating the Earth’s climate to mitigate the effect of global warming.

 

Physicist David Keith of the University of Calgary, Canada, said Gates’ donations were “philanthropic” money and he does not direct how the money is spent.

 

Gates is also an investor in Intellectual Ventures, a Seattle, Washington–area firm that pursues inventions and has applied for patents on techniques to geoengineer the stratosphere. Along with officials from that organization, Gates applied for a patent in 2008 to sap hurricanes of their strength by mixing surface and deep ocean water.

 

According to spokesperson John Pinette, Gates sees geoengineering as “a way to buy time but it's not a solution to the [climate change] problem.”