Scientists at the National Aeronautics and Space Administration (NASA) are saying the solar minimum they predicted three years ago is nothing to worry about.
The sun is dotted with sunspots, which are almost impossible to see with the naked eye. Those sunspots are constantly experiencing solar flares, or magnetic explosions that produce ultraviolet radiation and illuminate the Earth. However, roughly every 11 years or so, the sunspots fade and a solar minimum takes place.
According to NASA, the number of sunspots peaked in 2014 and were expected to hit a low point around 2019-2020.
So where does all that energy go? Dean Pesnell, project scientist of the Solar Dynamics Observatory at NASA, said that during a solar minimum, the energy put into causing solar flares in sunspots is instead, put into creating coronal holes, or areas in the sun’s atmosphere where solar particles escape and magnetic fields open up.
According to Pesnell, those holes, which last for around six months, are what can be responsible for disruptions of Earth’s magnetosphere — especially when solar particles hit Earth’s magnetic field.
Why Are Some People Worried About the Solar Minimum?
Astronomer Tony Phillips has suggested that the sunspot counts could produce one of the “deepest (solar minimums) of the solar system.” Researcher Irina Kitiashvili, who used NASA models, made a similar projection for the current solar cycle, positing that it could “be the weakest of the last 200 years.”
That could mean a repeat of the Dalton Minimum, which was one of the most extreme weather periods in history. The Dalton minimum was a period that lasted over three solar cycles from 1790-1830 and resulted in heavy snows, deep frost and general cooling around the globe.
According to The U.S. Sun, the Dalton minimum led to “periods of brutal cold, crop loss, famine and powerful volcanic eruptions … Temperatures plummeted by up to 2C over 20 years, devastating the world’s food production.”
A lower period of solar activity is sometimes referred to as a “Grand Solar Minimum.” The Maunder minimum, which took place between 1645 and 1715 in the Northern Hemisphere, led to a one-two-punch of cooling: volcanic activity resulted in a cooler stratosphere while low solar activity produced lower surface temperatures.
Some have referred to these periods as a “mini Ice Age” or “Little Ice Age.”
NASA Says Climate Change Will Offset Any Extreme Cooling
With a February blog post titled, “There Is No Impending ‘Mini Ice Age,'” NASA attempted to dispel the idea that a grand solar minimum could result in worldwide cooling.
In fact, NASA has predicted that climate change may negate any effects of the minimum:
In terms of climate forcing – a factor that could push the climate in a particular direction – solar scientists estimate it would be about -0.1 W/m2, the same impact of about three years of current carbon dioxide (CO2) concentration growth. Thus, a new Grand Solar Minimum would only serve to offset a few years of warming caused by human activities.
According to NASA, even if a prolonged grand solar minimum were to take place — which would occur over a decade — the warming from greenhouse gas emissions is six times greater than any cooling the minimum could produce. As a result, the globe would continue to warm.
In January, Space.com reported that two new sunspots were found by NASA’s Solar Dynamics Observatory, signaling the beginning of Solar Cycle 25 or SC25; those are expected to have a height of magnetic activity around 2025.