Science Daily: Global warming is mainly caused by greenhouse gas emissions resulting from human activities; however, current climatic variations may be affected “around 15% or 20%” by solar activity, according to Manuel Vázquez, a researcher from the Canary Islands’ Astrophysics Institute (IAC) who spoke at the Sun and Climate Change conference, organised as part of the El Escorial summer courses by Madrid’s Complutense University. In the past, the sun was the main external agent affecting climate …