ABSTRACT
Cycles of light and water, and adaptations to them, are at the heart of the human story on the Earth. Early humans observed the diurnal (daily) solar, the monthly lunar, the annual solar, and other astronomical cycles. But, the idea that nature’s cycles govern human and other life on the Earth is rooted in the human experience for millennia and has contributed very substantially to human evolution. Perhaps this idea about nature’s cycles also subconsciously underlies naming of climate phenomena as oscillations – for example, the Southern Oscillation, the North Atlantic Oscillation, the Pacific Decadal Oscillation, and the Atlantic Multidecadal Oscillation. In the climate science literature, there are three words used to describe non-steady climate – cycles, variations/variability, and change. Climate impacts or at least influences many aspects of human life: water–air–land–vegetation, commonly referred to as the environment; agriculture; health; transportation; natural resources such as forests and fisheries; and birds, animals, and terrestrial and marine ecosystems.
