Efforts to battle global warming and climate change may make things more difficult for sky watchers and astronomers. According to a new study, spraying of particles into the air so as to reflect sunlight and hence help reduce the temperature of earth might reduce light intensity in rural regions thus making the night skies duller and darker than usual. The process is called SAI – Stratospheric Aerosol Injection and while it is great for green causes, it isn’t good for stargazers.
In fact, according to Charles Zender who teaches at University of California in the department for Earth system science says that SAI would spell disaster for astronomy.
Growing Temperature Concerns
Ever since records on earth’s temperatures stretch back, the overall surface temperature has grown by a steady 1.1 degree Celsius. This covers a stretch of time spanning from the late 19th century till date. Add to that the record chart for hottest years in human recorded history contains 16 years starting from 2001 onwards. The previous three collectively have been hotter than ever before.
This trend of warmer temperatures is alarming and scientists are blaming the growth in carbon dioxide in the atmosphere, which traps heat and adds to global warming. The direct consequence of this is the receding Glaciers across the world. Many animal and plant species are migrating closer to mountain slopes or away from warmer habitats while birds are moving much earlier than before on their migratory trails.
All this points to the fact that the earth is getting hotter and SAI is our attempt at reversing the trends.
Engineering The Climate
What scientists are doing is nothing short of a miracle at a massive scale. With SAI, researchers believe that they can turn the clock back on global warming. It requires the use of high altitude balloons, planes and artillery to disperse sulphates and other particles high in the atmosphere so they start reflecting back sunlight.
Unfortunately, this isn’t the only climate engineering concept on the table. There have been many previously but collectively these ideas haven’t been properly accepted or applied. Scientists are still trying to figure out the side effects of such massive scale reprogramming of the climate before they take the plunge.
Among the studies to pinpoint side effects, a study to estimate how the night sky visibility would change was undertaken that revealed this complication of poor visibility. The result of SAI on a large scale would be amateur and professional astronomers will have a hard time gazing at the night skies. Brightness in urban areas would drop by 25 percent making it difficult to see a lot of things in the night sky.
Trying ground based optical astronomy would be more difficult in the future thanks to such climate changing theories. Infrared instruments though will have no complications because of their longer wavelengths.
Most astronomers though are willing to sacrifice some of the stars of the night sky if it means cooler climates globally and a control over greenhouse effect. After all, getting a handle over a hotter earth is more vital than astronomy.