Timo Niroma: Sunspots: 5. The 200-year sunspot cycle is also a weather cycle. PART 5. Sunspot cycles and supercycles and their tentative causes. 5. The 200-year sunspot cycle is also a weather cycle. * 5.1. A 2000-year historical perspective. -- The Roman Empire and its demise. -- The Mayan Classic Period. -- When the Nile froze in 829 AD. -- Why is it Iceland and Greenland and not vice versa? -- Tambora did not cause it. -- The spotless century 200 AD. -- The recent warming caused by Sun. -- The 200-year weather pattern. 5.1. A 2000-year historical perspective "The disturbances of the early third century were nothing compared with what would follow the end of the Severan dynasty in 235 AD. The half century from 235 to 284 AD was a period of unparalleled crisis, during which the Roman Enmpire nearly came to an end... This is a period for which comparatively little documentation exists, but that in itself may be symptomatic... Barbarian incursions were frequent and ruinous between 248 and 268... It was Diocletian who, in a reign from 284 to his voluntary abdication in 305, quelled the barbarians, defeated usurpers, and at the same time initiated sweeping political and economic changes that transformed the nature of the Empire, and ensured its survival for a while longer... In the mid fifth century the West was gradually lost. Areas like Spain and Africa were temporarily or permanently lost to the barbarians... In 439 Vandals took Carthage... In the 20 years following the death of Valentinian III (455 AD), the Roman Army proper dwindled to nothing." (Tainter 1988, pp. 137-148). Was there something like the Sporer minimum in the 200's and Maunder minimum in the 400's or rather vice versa as the following shows? What makes this a relevant question is that according to Schove there was only 7 cycles from 192 AD to 302 AD. This means that there most probably was 7 Jovian years plus a 27 year cessation. A real mother of all Maunders. Was this the reason for the Barbarian invasions at that time? Did they escape the terrible cold? And when the second cold spell came 200 years later, were also the Vandals attacking for the reason of the cold weather? Did the mighty Roman Army dwindle to nothing in just 20 years for this same reason? There were 220 years between the Barbarian incursions from 230 AD to 270 AD and demise of the Roman Army after the Vandals from 450 AD to 490 AD. Was it the warming of the climate that gave Diocletian and his followers the chance to revive The Roman Empire? There is one other historical moment whose simultaneous appearance gives this thought some credence. "The earliest inscriptions so far discovered in recognized Mayan lands are dated AD 292 and 320, dates on the threshold of the splendid Classic Period... The earliest date mentioned on inscriptions at Uaxactun is AD 328..." (Whitlock 1976). There is no known Columbus or other connector at that time between The Roman Empire and the Mayans. Now it seems like this 100/200-year Maunder-like cyclity continued. The period of 200 years seems to oscillate between 180 and 220 years. The 220 is best approximated by 100+120 years and the 180 years by 60+120 years. 120 years of warm period passed. Then in 608 AD Euphrates froze. After the warm 700's, in 829 AD Nile froze (Cambridge CCNet 1998). The century of 800's belong to the dark ages. Again we have here 220 years. "Another period of expansion [of the Mayas] extended from AD 731-90, when three splendid new centres were founded... Soon afterwards decline set in..." (Whitlock 1976)." "...the Maya of the Southern Lowlands, whose society underwent a rapid, dramatic, and justly famous collapse between about 790 and 890 AD." (Tainter 1988, pp. 152-153). "There is no trace of the large-scale destruction and fires which would have marked an invasion or an earth-quake." (Whitlock 1976, p. 26). "The Norwegian farmer Folke Vilgerdson made the first attempt to settle in Iceland in about 865 AD... He lost his cattle in a severe winter and disappointed went back to Norway after having seen a fjord filled up by sea ice. Therefore he called the country Iceland. Only a few years later, in 874, Ingolf Arnason succeeded. He was followed by many others, and settlement was completed in 930 AD... In 982, Erik the Red discovered new land West of Iceland. He called it Greenland; according to the Greenlander Saga this was only to persuade people to follow him... But the O(18) curve suggests that the name described a reality... So the drastic climatic change [warming] late in the ninth century may be part of the reason why Iceland and Greenland did not get the opposite names." (Dansgaard: Palaeo-Climatic Studies on Ice Cores, in Oeschger, Messerli and Svilar, 1980). "The beneficent times came to an end. Sea ice and stormier seas made the passages between Norway, Iceland and Greenland more difficult after AD 1200... In mainland Europe, disastrous harvests were experienced in the latter part of the thirteenth and in the early fourteenth century." (Grove 1988, pp. 1-2). The cold decades of 1680-1700 are very well documented, at least in Europe. (See for example Rothlisberger 1986). The glaciers in Alps increased, there was no good wine, harvests were a catastrophe and famine killed like the black death centuries before. Cold was also the decade of 1810-1820, including "the summer that did not come" or a "year without summer". The Tambora volcanic eruption has been accused for this summerless year 1816. Maybe it helped a little, but the cold spell had already begun from the spotless year 1810, with which Tambora had nothing to do. If we take the Schove estimates of the maximum magnitudes (R(M)) from the period 1500-1750 and the measurements from 1750, we get (the rounding for exact centuries done only to make the general picture clear): 1410-1500 ? cold (Sporer minimum) 1510-1600 107 warm 1610-1700 61 cold (Maunder minimum) 1710-1800 114 warm 1810-1900 95 cold (Dalton minimum) 1910-2000 151 warm 2010-2100 ? cold? So the supercyclic rise is a very long process, maybe a 1000- or a 2000-cycle or even longer. The Sun seems to be much more irregular than we ever have imagined. The historical data seem to show that the 200-year oscillation has been there at least since 200 AD. The even centuries seem to be have been cold, odd ones warm, not to the accuracy of year, but in the average anyway. If a spotless sun during the third century caused the process of the Great Roman Empire demise to begin, we have to write the history books anew. The other thing that seems apparent is that the general warming trend has been going on at least 1,800 years so that the third century AD may be the coldest century for at least 2000 years. Its only rival is the latter part of the 17th century. 1690's may have been almost as cold as the years 250 to 270. The cold periods later during the first millennium AD are more dramatical than the Little Ice Age thousand years later. On the other hand we may now live in the second mildest climate Anno Domini.Warmer periods seem to have occurred only between 1000 to 1200 AD. This may even have greater implications to the whole Holocene climate study and possibly to ice age theories also. Considering the evidence it looks a bit exaggerated and hasty a conclusion that the recent rise of half a degree would have been caused by man. So great are the natural variations. The evidence of man's role put into forefront in the IPCC Report 4 of 2007 is somewhat daring and based on very scanty evidence. If we compare the small warming and its oscillations during the 20th century with what has happened during the past, say 2000 years, we get a perspective that tells us how smooth and peaceful the, I would suggest, natural warming since the end of the Little Ice Age and especially Maunder Minimum has been. But man has always wanted to be in the center of the world. CO2 is the precondition for the multicellular life as we know it. Evidence is on the side that CO2 and its relation to Earth's temperature is a very complicated system. it's far from one-to-one relationship, there are so many intervening variables. One solar-based climate change may have a period of about 1050 years. There are many reports of a cold period beginning about 850BC (Geel et al.: Solar Forcing of Abrupt Climate Change around 850 Calendar Years BC), there begins around 200 AD a period of low cycles which transforms into a cold period around 230 AD (see above), consisting of a maximum length Gleissberg cycle and lastly the low periods beginning in 1250 AD (Schove) leading to the rapid deterioration of the climate beginning about 1270-1280 AD, which led to the end for the Medieval Maximum and for example to the demise of the Greenland habitat and forced Europeans to invent the warming system for their houses. The cold period lasted in all cases about 80 years beginning an oscillating period of 660 years. So there are intervening some 400 years of a warm period (for example the Medieval maximum).