You may have recently heard or read in the news that the sun has “gone quiet”. Over the past week, for the first time since 2011, the sun had a day where no sunspots were observed (see image below). We may very well see other days this year where no or very few sunspots are observed as the most recent solar cycle begins to wind down.
You may be wondering why it may be or may not be important to observe solar activity when it comes to our weather. There is good reason to closely monitor the sun’s activity. There are strong correlations between the sun’s activity (sunspots or lack thereof) and our climate.
Currently, there are raging debates on exactly how much the sun’s activity may impact our weather and climate. Some only want to measure the sun’s total solar irradiance (brightness) and its possible impacts on our climate. Others take into account much more than the sun’s brightness. For example, some other scientists think sunspots and the amount of cosmic rays impacting the sun (depends on the number of sunspots), changes in ultraviolet light changes, geomagnetic storms and total solar irradiance can impact our weather and climate.
For example, the IPCC (the United Nations Interplanetary Panel on Climate Change) only takes into account the sun’s brightness (total solar irradiance) and ignores, sunspots, cosmic rays, etc.
There are compelling connections between the number of spots or lack thereof and periods of warm and cold in Earth’s history. Cooler periods in history have a shown strong correlation with low sunspot activity (Little Ice Age) while warmer periods have coincided with increased sunspots (1990s and early 2000s).
There may be tantalizing clues about our weather and climate hidden in the sun that we are only now beginning to understand, so keep a close watch on solar activity in the future.