Climate Change Denial Myth #1: Is Climate Change Caused by Solar Activity?

There are many people, primarily those supporting the Republican party in the United States, who deny climate change is real or claim change change is real but a result of natural causes. Both claims are wrong and proven to be wrong by sound science. I'm starting a new series on climate change myths and the first has to do with solar activity. Is climate change real but naturally caused by increased solar activity? The short answer is no. The long answer is also no.  :-)

The Sun.

The Sun provides Earth with energy and any increase in solar energy output has the potential to change Earth's climate. Does Earth's solar activity change?  The answer is yes. The Sun goes through an 11 year cycle in which activity starts at a maximum, drops to a minimum, and increases back to a maximum. During solar maximum, solar flares and solar sunspots are more frequent. Does this alter Earth's climate? The answer is no. If it did, we'd see climate changes matching the Sun's 11 year cycle. During periods of solar maximum, temperatures on Earth would increase. During periods of solar minimum, temperatures on Earth would decrease. But this is not what we see. We see a continued increase in surface temperatures regardless of solar activity. The graph below using real data shows very clearly there is no relationship between solar activity and temperature on Earth.

Plot taken from "https://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm" with the following caption: "Annual global temperature change (thin light red) with 11 year moving average of temperature (thick dark red). Temperature from NASA GISS. Annual Total Solar Irradiance(thin light blue) with 11 year moving average of TSI (thick dark blue). TSI from 1880 to 1978 from Krivova et al 2007. TSI from 1979 to 2015 from the World Radiation Center (see their PMOD index page for data updates). Plots of the most recent solar irradiance can be found at the Laboratory for Atmospheric and Space Physics LISIRD site."

There is no trend at all and it would be silly to claim solar activity is causing the drastic temperature increases we've seen over the last 50 years. Solar activity does play a role over very large time periods of hundreds of millions to billions of years. The Sun's activity will slowly increase as it ages and eventually raise temperatures on Earth to the point that Earth is no longer in the habitable zone. But this will not happen for another 500 million to 1 billion years. A much, much different time scale than the half-century we see our current climate changing.  

To sum up, yes, solar activity changes, but it has ups and downs. This activity does not correlate at all with rising temperatures on Earth. Over hundreds of millions to billions of years the Sun will play a role in changing our climate, but it plays no role over the changing climate of the last 50 years. The current climate change is directly related to humans burning fossil fuels.