Top Pro & Con Arguments
Global warming and cooling are primarily caused by fluctuations in the sun’s heat (solar forcing), not by human activity.
According to a study published in the Journal of Atmospheric and Solar-Terrestrial Physics, 50-70% of warming throughout the 20th century could be associated with an increased amount of solar activity.  Between 1900 and 2000 solar irradiance increased 0.19%, and correlated with the rise in US surface temperatures over the 20th century. 
A study published in Energy & Environment wrote, “variations in solar activity and not the burning of fossil fuels are the direct cause of the observed multiyear variations in climatic responses.”  In a study by Willie Soon, PhD, Physicist at the Harvard-Smithsonian Center for Astrophysics, a strong correlation between solar radiation and temperatures in the Arctic over the past 130 years was identified. Read More