This completely updated new edition of Weather Cycles: Real or Imaginary? explores in detail the unresolved debate on the existence of weather cycles. The book examines the competing arguments for observed effects being due to natural variability, solar activity and the Earth's orbital parameters. It provides a different perspective on one of the most difficult questions in the current global warming debate: namely, just how much of the recent temperature rise can be attributed to natural causes? Only by understanding how the climate can change of its own accord, and whether observed shifts are part of a set of predictable patterns, will it be possible to reach a reliable judgement on how much impact human activities are having. This book examines the complex analysis required to assess the evidence for cycles with a minimum of mathematics. This comprehensive and balanced account will appeal to the student and expert alike.