Renowned scientist, Professor Wally Broecker, will give a talk on what we may need to do to avoid dangerous climate change. He will discuss the need to remove CO2 from the air and proposals to reflect a proportion of the Sun's radiation back into space.
Abstract: Considering the extremely slow progress in our drive to switch to non-fossil fuel energy sources, we must come up with alternate interim strategies to ease the impacts of increasing CO2. At the top of my list is CO2 capture and storage and, in particular, direct CO2 capture from the atmosphere. I believe that it can be done for about 15 percent of the cost of fossil fuel energy. It would likely involve modular devices, each of which would capture let's say one ton of CO2 each day. One hundred million such devices would be required to capture the CO2 we are currently producing. Another 100 million would be required to bring CO2 down by 2.5 ppm per year. These units would be deployed in dry waste lands well away from urban areas. The CO2 would be stored in geological strata beneath them. The energy would come from local sunshine and wind. Lurking in the background is albedo modification created by adding SO2 to the stratosphere. This band-aid will be tempting as it would be an order of magnitude cheaper. Also, it could be effective on the timescale of years rather than decades. Like it or not I suspect that if we remain on the business-as-usual path, it will be tempting to opt for interim albedo modification. As we are headed for big trouble, we must get our heads out of the sand and design a safety net!
Professor Wally Broecker is the Newberry Professor in the Department of Earth and Environmental Sciences at Columbia University. He developed the idea of a global "conveyor belt" linking the circulation of the global ocean and has made major contributions to our understanding of the carbon cycle and the use of chemical tracers and isotope dating in oceanography. This event is open to everyone - there is no need to register.