Space Weather is watched carefully. It includes plasma, radiation, magnetic fields and other matter in space. Much space weather reflects solar activity.
Spots on the sun come and go. Overall there appears to be a cycle which lasts about 11 years and which correlates with lots of space weather phenomena. One of the prominent phenomena that correlates is northern lights or Aurora--a feature of the night sky in the Keweenaw.
We are currently in a solar activity minimum which has resulted in low levels of aurora for several years. Scientists are now forecasting the end of this cycle. An important point of discussion about global warming concerns whether the solar activity cycle, linked to solar luminosity, could be influencing global climate.
Many people ask whether the global temperature changes that have been measured could simply be explained by solar activity--that a hotter sun is causing it, not atmospheric changes on earth. In the plot below, we see that solar activity changes in the past 40 years (blue curve) are quite different from global temperatures (red curve).
