WRAL WeatherCenter Blog

Are the sun spots contributing to our present drought?

Posted October 15, 2007 9:04 a.m. EDT

MIKE MOSS SAYS:      Erin,     It can be very difficult to establish any confident link between something like the number of sunspots and changes in weather on Earth, although some studies have shown statistical links with some aspects of large scale circulation, cloud formation, and other weather-related variables. However, establishing well-understood physical links between the very small variations in total solar radiation (and somewhat larger variations in UV radiation) associated with variations in sunspot number and earthly weather effects has been elusive, especially for effects concentrated over a particular region, as with the drought across parts of the southeast this year. In addition, we are right at the minimum point in the roughly 11-year cycle of increasing and decreasing sunspots, and today, for example, no sunspots are observed on the solar surface. Since sunspot activity has been quite low for a couple of years now, and was quite high during the last serioud drought here, it seems unlikely that we can associate sunspots with our current drought.