By Meghna Murali
According to recent reports from NASA, the sun is slowly dimming, that is, cooling down. The phenomenon, termed as the “Grand Minimum”, could perhaps be witnessed as soon as 2020. However, will this phenomenon have any adverse effects on planet Earth?
What is the Grand Minimum?
All objects in space undergo tremendous changes over a period of time. They are either defined by the nature of their orbiting periods or the duration of their life cycle. In a similar fashion, the sun undergoes a series of chemical changes every 11 years. The solar cycle or the solar magnetic activity cycle is a periodic cycle of 11 years. During this course, the sun’s capacity to emit radiations changes. In terms of its appearance, one can spot changes in the number of sunspots, flares, and other manifestations.
The Grand Minimum, also known as the Solar Minimum is a period which occurs during the course of the 11-year cycle. The sun is the least active during this period. The sunspots and the flares vanish for days together, leaving behind drastic changes on earth. The Solar Minimum has a very erratic cycle. Thus, predicting the exact date of the Minimum is a difficult task.
The Maunder Minimum: A Little Ice Age period
The last Grand Minimum took place in the middle of the seventeenth century. Named as the “Maunder Minimum”, it lasted between 1645 and 1715. English astronomer Edward Maunder had noticed a decrease in the number of sunspots. To prove his statement, he conducted a detailed research on the amount of Carbon-14 present in the sun. On combining the results from the 17th and the 18th century, Edward noticed a drastic decrease in the sun’s activity.
The Maunder Minimum had devastating effects on the earth. The northern hemisphere froze completely. The period was coined as the ‘Little Ice Age’. The Thames river in England froze completely, fertile lands turned into glaciers and the Norwegian farmers lost their only source of livelihood.
Will the Grand Minimum give rise to another ice age?
According to a new study, the effects of the Grand Minimum will not be drastic this time. Since the Maunder Minimum, the average global temperatures have been on an exponential rise. The rate of global warming does not seem to be decreasing. One might experience a slight drop in temperature, which in turn might decrease the effect of global warming. Besides these changes, the amount of UV radiation could potentially decrease.
By studying the relationship between the earth and the sun’s activity, scientists will be able to create more accurate climate model simulations. “We can, therefore, have a better idea of how changes in the solar UV radiation affect climate change on Earth,” said Dan Lubin, a research physicist with the Scripps Institution of Oceanography at the University of California, San Diego.