Reducing the amount of sunlight that hits the Earth may help reduce the detrimental effects of climate change. Scientists have performed a study on the affordability and feasibility of delivering solar geoengineering materials into the stratosphere in order to reduce this effect.
The study has revealed the possibility of performing such an initiative within a budget of less than $5 billion a year. The technology to perform the delivery exists and it can be implemented in many methods. It has been estimated that the cost incurred for reducing CO2 emissions will be around $200 to $2000 billion in 2030, which is equivalent to around 0.2% and 2.5% of GDP.
More study of the costs, risks and results of solar radiation management (SRM) need to be performed before considering it as a strategy to mitigate the effects of incident sunlight. Moreover, neither the increasing acid content of the oceans nor the greenhouse gas concentrations can be reduced by reducing incident sunlight.
A team of researchers conducted an engineering cost analysis of using six potential systems for delivering the material. Existing aircraft, guns, rockets, new hybrid airships, new customized aircraft and suspended pipes designed to carry gas or slurry were considered. The systems had to be capable of delivering from one to five tons of material to altitudes ranging from 18 to 30 km.
The researchers belonging to the Carnegie Mellon University, Harvard University and Aurora Flight Sciences found that among these possibilities, developing specialized new aircraft was the most economical option. This was estimated to cost around $1 to $2 billion annually.
The study has been published in Environmental Research Letters, a journal from the Institute of Physics.