Daggers are drawn over revived cosmic ray-climate link

Last year, climate change scientists thought they had driven a silver stake through the idea that fluctuations in solar activity were behind global warming in the last century. Now, a high-profile team led by geophysicist Vincent Courtillot, director of the Institut de Physique du Globe in Paris, has sought to raise the dead in a paper linking changes in Earth's magnetic field to temperature variations in recent millennia.