Listen to this article The Climate Change Solution Reflecting Sun Away from Earth
Introduction
The United Nations Environment Program (UNEP) released a report on Monday, indicating that global efforts to respond to climate change are inadequate, and it is time to study technologies that reflect sunlight away from Earth to cool it down temporarily. While reducing greenhouse gas emissions is the only way to permanently slow global warming, the worldwide efforts are not on track to meet the 1.5° Celsius Paris Agreement goal, the report added. The UNEP advised that it is currently not a good idea to use Solar Radiation Modification (SRM) technologies to respond to climate change, but this view may change if climate action remains insufficient. The report highlights the need for rigorous study of both the technologies and the potential international governance.

The Need for Solar Radiation Modification Technologies
Solar geoengineering, a category of technologies that reflect sunlight back away from Earth, could be considered a one-time shot to mitigate extreme suffering and death caused by climate change. The report suggests that these techniques can cool the Earth within a few years and would cost tens of billions of dollars per year per one degree Celsius of cooling. While the technology to inject large quantities of aerosols into the upper atmosphere does not exist today, it could be developed in under ten years. Scientists know it works quickly, citing the drop in the global average temperature after large volcanic eruptions have spread large quantities of aerosols into the upper atmosphere.
The Risks of Solar Radiation Modification Technologies
While Solar Radiation Modification technologies could buy more time to aggressively and permanently reduce greenhouse gas emissions, they can also be dangerous. Sulfur dioxide, commonly proposed as an aerosol, would result in acid rain and could increase ozone depletion, delaying the Antarctic ozone hole recovery by a couple of decades and making it deeper in the first decade of SAI deployment. There is little information on the risks of SRM and limited literature on the environmental and social impacts of these technologies. Even as a temporary response option, large-scale SRM deployment is fraught with scientific uncertainties and ethical issues. The evidence base is simply not there to make informed decisions.

The Need for Global Governance and Cooperation
The report highlights the need for globally coordinated governance strategy for any potential use of Solar-Geoengineering technology. Moreover, experts said that right now, we just don’t know enough about the side effects of these technologies. Additionally, the relatively low cost means it is “within reach” of many countries and organizations, opening the possibility of a “rogue deployment,” the report said. Furthermore, the United Nations could be a leader in global discussions of solar geoengineering conversations, the report said, noting that not having international cooperation and governance is potentially dire. Assuming a universal consensus in the broader community on an SRM deployment is highly unlikely. Hence, communities, nations, and societies that oppose SRM deployment could face the effects of such deployment against their wishes, leading to ethical and legal concerns.

Conclusion
Although Solar Radiation Modification (SRM) technologies may offer a temporary remedy to the global climate emergency, we cannot disregard the risks and uncertainties linked with these technologies. The world must prioritize reducing greenhouse gas emissions and other long-term solutions to slow global warming. If these efforts remain insufficient, it may be time to consider these speculative technologies. However, they must be studied rigorously and implemented with globally coordinated governance strategies to minimize the risks and ensure that they do not cause harm to the environment and society.