Terrestrial Climate and the Solar Cycle

Sunspots and weather

“…This mechanism appears to be reflected in data for British soil temperatures, European atmospheric pressure and rainfall, etc. [Lawrence, 1965a]. Also, Brooks [1923] shows that from 1896 to 1922 some eentraI African lake water levels were in phase with the 'eleven-year' sunspot cycle, but more recent data exhibit a tendency for the reverse pattern.…”

“…It is reasonably possible that some changes in solar radiation could result in a more continental climate with lower winter temperatures and higher summer temperatures but that more extreme changes of sunspots and 'continentaltry' could result in lower temperatures in both summer and winter, perhaps because of more vigorous development of heat (thermal) lows over continents in summer [Lawrence, 1965a]. Such a process seems not to have been considered, for example, by Shaw [1965] or by Wexler [1956] in his work on the variation in insolation, general circulation, and climate.…”

“…Such results may not be very encouraging, but conclusive unfavorable deductions regarding the possibility of sunspot-weather relationships cannot be justified until allowance has been made for the fact that all sunspot cycles are not identical and until phases of the sunspot cycle, other than sunspot maximums and minimums, have been compared. Work described elsewhere [for example, Cochrane, 1957;Brier, 1961;Lawrence, 1965aLawrence, , 1966 suggests that, if specific attention is given to varying sunspot cycle amplitudes, etc., differences in weather elements between these other parts of the sunspot cycle can yield more significant patterns.…”

“…This pattern is confirmed by the increase in September storm frequencies in West Pakistan and corresponding mean sea temperatures in the Bay of Bengal, where these storms originate as developments in the northern equatorial trough [Frost, 1966]; during the two periods 1900-1929 and 1930-1959, there were 4 and 12 storms, respectively, and the corresponding mean sea temperatures were 27.9 and 28.6øC. These two periods are separated approximately by one of the sunspot-weather phase changes discussed earlier (by a change from small to large sunspot amplitudes), and, because of the suggested link between sunspot-weather patterns and latitude [Lawrence, 1965a], it must be conceded as at least a possibility that the change of rainfall regime is linked with sunspot changes, and therefore variations in sunspots and latitude should be incorporated in any investigation into Indian rainfall calendaricities.…”

A Possible Correlation Between Sugar Beet Yellows Incidence and Sunspot Activity

“…As with other diseases, the incidence of virus yellows differs greatly in different years; since 1946 there have been two periods (1948-50 and 1957-61) when it was common and widespread, with intervening periods when it was less prevalent. Long-term fluctuations of climate and climate-influenced phenomena have often been correlated with the cyclical changes in the number of sunspots (Lawrence, 1965;Williams, 1961), and it is interesting to find that since 1946 the periods of greatest sunspot activity coincide with the periods when yellows was most prevalent (Fig. 1).…”