My readers may remember a column from last winter in which I discussed the exceptionally quiet, spot-free Sun. At that time, I suggested we may be entering a period of reduced solar activity, much like the Maunder (or shorter-lived Dalton) minimum, that would likely be accompanied by a world-wide cooling trend and significantly harsher winters. Although a few spots have appeared from time to time since I wrote that column, the Sun has remained unusually quiet; nothing has happened to contradict the hypothesis that we are, in fact, a few years into a Maunder- or Dalton-type minimum. Not only has the Sun been seriously lacking in spots, but my prediction last year of harsher, snowier winters is being confirmed by recent events. So far, this winter has been brutal, hitting us with unrelenting snowstorms; in January alone over 36 inches of snow fell in New York breaking the old record of 27.4 inches set back in 1925!
What will our climate be like during a solar minimum? If you read Charles Dickens, you will know that in the 1800s, around the time of the Dalton minimum, it snowed regularly in London. Closer to home, New York rivers often froze over allowing access to the city by horse or on foot! This was during the late 1800s and early 1900s, when solar activity was still rather low. Many readers probably have personal experience of the winters of the 1950s, 1960s and even the 1970s, which reflected a period of reduced solar activity and a cooler global environment. Since the 1980s, we have experienced atypically high solar activity. This, more than greenhouse gasses, may have contributed to global warming and milder winters in recent decades. Since the Sun has lost its spots, however, the warming trend may reverse, leaving us with what is, historically, a more normal climate.
Given the harsh winter and talk of cold and snow, it is nice to know that spring is near. The Vernal Equinox, which marks the first day of spring, falls on March 20. It is the day when the Sun crosses the equator resulting in equal amounts of daytime and nighttime. It is also the time when the pace at which the days grow longer is greatest. Of course, longer days and a Sun that rides ever higher in the sky bring with them warmer, more pleasant weather.
There are no big meteor showers in March. Saturn happens to be the only planet up in the evening, but viewing, especially through a good telescope, should be excellent. Of course there are always galaxies, nebula, comets, asteroids and other interesting things out there worthy of study.
Quiet, spotless sun. Photo courtesy of NASA.