CLIMATIC IMPLICATIONS OF THE IMPENDING GRAND SOLAR MINIMUM AND COOL PACIFIC DECADAL OSCILLATION: THE PAST IS THE KEY TO THE FUTURE--WHAT WE CAN LEARN FROM RECURRING PAST CLIMATE CYCLES RECORDED BY GLACIAL FLUCTUATIONS, ICE CORES, SEA SURFACE TEMPERATURES, AND HISTORIC MEASUREMENTS

We are witnessing the beginning of a rare solar event—a Grand Solar Minimum (GSM) that hasn’t occurred for 200 years. The event is in its early phases so the effects of this event remain to be seen, but each past GSM has coincided with significant climate changes. The Dalton Solar Minimum from 1790 to 1820, was a time of sharp global cooling, and the Maunder Solar Minimum (1650-1700), brought with it severe cooling of the Little Ice Age that devastated human populations. The present rate of declining solar magnetic field suggests that sun spots may disappear for several decades, similar to what happened during the Dalton and Maunder Solar Minima.

Oxygen isotope measurements from the Greenland GISP2 ice core reveal at least 40 oscillations of warm/cool periods in the past 500 years spaced an average of 27 years apart, essentially the same as the Pacific Decadal Oscillation. In 1999, sea surface temperatures in the eastern Pacific switched from warm mode, where the Pacific had been since 1977, to cool mode, which has remained since 1999. The pattern of warm/cool climate changes over the past 500 years and during the past century suggests that recent cooling is following the same cyclic pattern.