Solar observations -- The physical properties of the Sun -- Solar activity -- Earth's climate -- Solar activity and the stratosphere -- Solar magnetism and Earth's climate -- A review of solar-terrestrial studies -- Solar activity and regional climate variations -- Synthesis. DO SUNSPOTS AFFECT OUR CLIMATE? This question has been a focus of scientific debate since the existence of sunspots was established in the early 17th century. Even today, however, the answer is not forthcoming; while there are valid reasons to believe that solar activity has some impact on the Earth's climate, the history of the subject shows that there have been many unsupported statements that over-estimate the effect of sunspots on climatic variations. This updated and revised edition of "Solar Activity and Earth's Climate" introduces the reader to the subject of solar activity and the connection with the Earth's climate. It focuses on how knowledge about the solar cycle and Earth's climate is obtained, and provides an in depth discussion of observations, methods and the physics involved, together with the necessary statistics and analysis