Our inability to take immediate and effective measures to curb emissions of greenhouse gases into the atmosphere has been increasing the severity of climate change with each passing day. There has come a point where we can not wait any further for our behaviour to change and now, we must start exploring other alternatives so that we are better prepared for an inevitable climate change catastrophe in the future. Creative minds across the world are trying to find out solutions to climate change. Marine cloud brightening — one of the many climate engineering solutions to climate change — has been a hot topic of discussion for many years, however, the risks involved in its implementation at a larger scale and its moral implications continue to question its feasibility.
The marine cloud brightening technique –which falls under the category of solar radiation management (SRM) — works by intervening the clouds’ albedo effect which is the ability of the cloud to reflect sunlight to space. This climate engineering technique involves the spraying of naturally occurring saltwater from the oceans into the air which could make the clouds above the oceans brighter and thus increasing their albedo effect or reflectivity which would reflect a much greater amount of radiation away from our planet. This would help in bringing down the temperature of the earth and thus will have an overall cooling effect over the globe.
Fine nozzles to reduce saltwater into tiny droplets are being developed which will be sprayed into the atmosphere. The spray of these tiny droplets of salt water will be seeded into the clouds which will promote the formation of cloud micro-droplets. This is in contrast to cloud seeding technology where large droplets are formed to produce rain. In marine cloud brightening technique, the droplets are smaller and they remain in the sky making its appearance as “white cloud”. These micro-droplets not only enhance the scattering of incoming radiation but they also boost the longevity of clouds. It is worth mentioning here that marine cloud brightening can be implemented only in limited areas with specific clouds — which accounts for just 10 per cent of the surface of the planet.
This deliberate intervention in the working of weather and climate processes could have some serious repercussions for the entire planet and its population. This technique sure does bring cooling effect but we are not yet certain how its implication at a large scale will affect the precipitation patterns at a global level and this unpredictability could be devastating for all of us. Further, it just gives a partial fix to our climate change problems and does not address the causes of climate change which is greenhouse gases emissions and global warming. Dealing with the symptoms could bring some temporary relief but for a permanent solution, the best one is still the reduction of greenhouse gases into the atmosphere. So, why the need for the research in this technology? No doubt, they are too risky to roll out in present conditions when we do not have enough data on its implications but its investigation would create an emergency back up plan in case the climate change becomes too severe to bear.