7th July 2019
The Little Ice Age (1280–1850 AD)
TEMPERATURES HAVE RISEN AROUND 5 DEGREES CELSIUS OVER THE PAST 500 YEARS
Extract from Chapter 1 of the Don Easterbrook edited book Evidence-Based Climate Science pic.twitter.com/7TrxDePThn
— Sanjeev Sabhlok (@sabhlok) July 9, 2019
GLACIERS HAD DRAMATICALLY EXPANDED BY 1915, THEN STRONGLY RECEDED BY 1945, THEN STRONGLY EXPANDED BY 1977.
When CO2 INCREASED dramatically the glaciers first EXPANDED. pic.twitter.com/Px6N0LHmEc
— Sanjeev Sabhlok (@sabhlok) July 9, 2019
Extract from Plimer
The Medieval Climate Optimum ended rapidly with the Little Ice Age, starting in 1303 AD. This major climate change took only 23 years. It led to famine, depopulation, war and disease.296 The Little Ice Age started when the Sun again became lazy. The Wolf Minimum (1280 to 1340 AD) was a time when there were few sunspots, and the lack of solar activity resulted in increased cloudiness. The planet became cold. The Little Ice Age had a number of intense periods when the Sun emitted less energy. These were the Spörer Minimum (1450–1540 AD), the Maunder Minimum (1645–1715 AD) and the Dalton Minimum (1795–1825 AD).297 The Maunder Minimum was the most bitterly cold time of the Little Ice Age. Times of feast suddenly changed to times of famine.298 The Little Ice Age was not a good time to be alive on planet Earth.299
The Little Ice Age was not really an ice age. In reality, it was a cool interval within the current interglacial. What made the Little Ice Age particularly difficult was that there had been hundreds of years of warmth in the Medieval Warming and the increased population was supported by subsistence farming. Subsistence farming was later replaced in Britain by specialist farming to support city populations. The Northern Hemisphere had adapted to warm times and was not prepared for the sudden onset of cold times. This created an environmental catastrophe. There was massive depopulation. This catastrophe was global. Pacific Island populations were greatly reduced at the beginning of the Little Ice Age.300 Other parts of the world were cold and dry, especially during the Spörer and Maunder Minima.301 Not only was it cold during the Little Ice Age, but there were rapid fluctuations in temperature and precipitation. During the Maunder Minimum, a year of record cold temperatures (1683–1684) was followed by a year of record heat (1685–1686). Change to glacial climate is characterised by drastic changes in temperature, storminess and precipitation without warming. These changes were local, global and rapid. They had a profound effect on human society.302
We have a reliable picture of the extremely cold periods during the Little Ice Age from the weather records. Private diaries, ships’ logs, accounts of military campaigns and similar sources give descriptions of the wind directions, wind speed, cloud formations and other weather indicators. Precisely dated annals, chronicles, audited accounts, agricultural records and tax ledgers provide indirect information, particularly on extreme weather events. Records of wine grape harvests, salt harvest from evaporation pans and grain prices are a good proxy for temperature, rainfall and wind. For example, the price of grain was higher in periods of weak solar activity (Maunder Minimum 1645–1715 AD and Dalton Minimum 1775–1825) when Europe was extraordinarily cold. Additional evidence from debris left behind by glaciers, lake and ocean muds, pollen and insects in mud, tree rings, coral growth structures, ice core analysis, boreholes, archaeological site investigations and historical records can all be used to reconstruct the conditions during the Little Ice Age. It was not a pretty sight.303
The cold climate and glacier expansion in the Little Ice Age are documented from all continents and on major islands from New Zealand in the South Pacific Ocean to Svalbard in the Arctic Sea.304 The Little Ice Age was not a single, uniformly cold episode. There were warm and exceptionally cold periods and distinct variations in climate and glacier activity took place on a regional basis. In Europe305 and North America306, at least six phases of glacier expansion occurred. These were separated by warm periods.307,308
Corals in the Florida Straits reveal variations in C14 during the Little Ice Age,309 which shows that the Earth’s atmosphere was being bombarded by additional cosmic rays in the coldest time of the Little Ice Age. The coral carbon chemistry shows that the Maunder Minimum in Florida was at the same time as the Maunder Minimum in Europe. The effects of the Little Ice Age must have been widespread.
Studies of lichen are able to give a window into the extent of ice in the Little Ice Age in Iceland.310 Four glaciers were studied and these show that the maximum ice extent was in the mid 19th Century and that there is a relationship between the mass of glacial ice and mean summer temperature.
Elsewhere in North America, the forests also responded to the extreme cold of the Little Ice Age.311 The foxtail pine and western juniper of the southern Sierra Nevada Mountains show that it was warmer than current times from 1100 to 1375 AD and colder from 1450 to 1850. Tree rings in the long-lived bristle cone pines on the California-Nevada border show that some trees are 5500 years old. From 800 AD to the present, the hundred-year averages of temperature correlate statistically with the temperatures derived from central England.312
History and knowledge of modern times show that the world was a different place in the Little Ice Age. In the second half of the 17th Century, the French army used frozen rivers as thoroughfares to invade the Netherlands, while New Yorkers walked from Manhattan to Staten Island. Sea ice surrounded Iceland, trapping the population and causing famine. This was not the first time this had happened. In the period 1420 to 1570, Vikings on Greenland lost their livestock, agriculture and lives in the first phase of the Little Ice Age. There is a view that the chronic shortages of grain and bread in the late 1700s in France due to poor climate led to the social discontent that fuelled the French Revolution.
The Little Ice Age had two cold phases and included four intense cold periods at times of reduced sunspot activity. This has been validated by measuring heavy and light oxygen isotopes in cave stalagmites from Ireland. The stalagmites also identified the Medieval Warming, the Dark Ages and the Roman Warming.313 Glaciers advanced and retreated in the Little Ice Age. During glacial advance, European alpine villages were destroyed and forests were flattened. The northeast Pacific region of Alaska shows evidence of two major glacial advances that destroyed forests. Glaciers stabilised after advancing, some retreated slightly and the glacial fluctuations were on a decadal scale.314 This also shows that the Little Ice Age was not restricted to Europe.
During the first phase (1280–1550 AD) of the Little Ice Age, the climate was far more variable than in the Medieval Warming or the second phase. The extreme variability brought warm and very dry summers in some years and very cold wet summers in other years. Storm frequency in the North Sea and the English Channel increased.315 There were Arctic winters, stinking hot summers, major droughts, torrential rains and floods, long winters and long summers. In high latitudes, the Little Ice Age was heralded by the growth of the ice sheets in Greenland in the early 13th Century. Ice then covered much of Iceland, Scandinavia and northern Europe and landslides, avalanches and floods were far more common.316
The Gulf Stream, which helps to bring warm weather to much of the North Atlantic region, was significantly weakened during the Little Ice Age.317 It is suggested that from 1200 to 1850 AD, the Gulf Stream, a vast pattern of currents that carries warm surface waters from the tropical Atlantic northeast towards Europe, decreased in flow by some 10%, thereby transporting less heat to Europe.318 Foraminifer fossils from sediment cores show that there was a southward shift of the zone of tropical rain that feeds fresh water into the Atlantic. This rain produces a less dense top layer of water that bolsters the surface current flowing north.
In Eastern Europe, pronounced variability in the weather appeared in the 12th Century. In Western Europe, the 14th Century was very wet, especially between 1313 and 1321. In 1315, crops failed. It was wet and cold. Torrential rains removed topsoil. Harvests very commonly failed in the shortened growing season. Areas at altitude and high latitude that had been fertile fields during the Medieval Warming were abandoned because of the lower temperature and increased wetness. Landslides in alpine areas became more common319 and, together with advancing glaciers, destroyed many villages. With crop failure, famine, the bubonic plague and the collapse of society, the feudal system of Europe started to fall apart. The stressed human population of the Northern Hemisphere was attacked by the plague in 1347. The depopulation was so intense that it took 250 years for the Northern Hemisphere population to return to the levels of 1280. The plague, the Black Death, was the midwife to modern Europe. It appeared in the Dark Ages when it was cold and again appeared in the Little Ice Age. The Little Ice Age probably was the forcing mechanism for the plague. The rapid spread of the plague was assisted by huge segments of the population who had left the fields and lived in cramped quarters in towns.320
Marine life migrated as the sea ice advanced. The cod fields that had served the Vikings well retreated, as cod have a limited tolerance to low temperature and suffer kidney failure at temperatures of less than 2ºC. In Norway, Greenland and Iceland, the abundant supplies of fish that were an essential source of protein disappeared. Sweden and Finland also had an expansion of ice and a loss of agricultural land321 and tax records show that there was destocking and economic collapse in the highlands of Norway.322 Some five years after Christopher Columbus “discovered” North America, Basque fishing boats were catching cod off the east coast of Canada. They had probably been fishing these waters for centuries before the New World was discovered. In an especially cold period in the mid-late 1600s (Maunder Minimum), the abundant cod disappeared from the waters around the Faeroe Islands.
Land abandonment, crop failure and soil losses were catastrophic because 90% of the population were subsistence farm families who needed enough grain to see them through winter and enough spare grain to sow for the following year’s crop. Both the quantity and quality of harvests were vital for survival. Grain rotted in the fields and sometimes couldn’t be planted at all. Crop failure led to famine, famine led to disease and death, famine led to a breakdown in society and even cannibalism. Gangs of desperately hungry peasants roamed the countryside searching for food. The harvesting and storage of wet grain, especially rye, stimulated ergot fungus which ruined grain stockpiles. Hungry people ate mouldy grain which contained fungal toxins. This led to ergotism (St Anthony’s Fire) which causes convulsions, hallucinations, mass hysteria and death. In extreme cases, internal poisoning from fungal toxins leads to gangrene causing victims’ limbs to fall off.323 Woodcuts from the 14th Century show St Anthony surrounded by detached hands and feet. The ghastly weather was a clear sign to some Christians that Satan was dominating the Earth. Witches were blamed and thousands were burned because it was well known then that witches caused continuous crop failures.324
The typical northern European dwelling was a small room with an earthen floor, no insulation, no glass in the windows and a leaky thatched roof. People sat around a central fire on low stools to avoid smoke. Wood was scarce because it required ownership of a forest and metal cutting tools. The overcrowding, dampness, persistently damp clothing, malnutrition, poor sanitation and scarcity of heating fuel were an ideal environment for disease. Epidemics of typhoid, spread by lice, were more common in winter because malnourished people huddled together in huts to share body warmth and fires. Colds turned to pneumonia. Tuberculosis thrived in crowded areas, as did typhoid, diphtheria and whooping cough. Disease in the Little Ice Age resulted in massive depopulation. And, while huddled around the smoky fire, what did the Europeans talk about? The weather, of course.
The cold weather led to inventiveness. Glass windows were a response to these times. They kept out the cold and still allowed a view of the world. The Dutch thrived as fish migrated from high latitudes into Dutch waters. The repeated violent storms of the 16th and 17th Centuries led the Dutch to develop the technology to reclaim low-lying land from the sea.325
The trade and travel of the Medieval Warming ended. At times, the seas were stormier and the waves were higher. There was increased sea ice. On the land, roads became impassable bogs, mountain passes were closed for long periods and trade fairs were a thing of the past. By the 1340s, the sea route between Iceland and Greenland had to follow longer, more southerly routes to avoid ice and treacherous weather.326 In the 13th and 14th Centuries, fierce storms devastated large tracts of the lowlands of north Germany, Holland and Denmark.327 More than 100,000 people were killed.
Desperation set in among the Norse colonies in Greenland, where there was a shorter growing season and less grass for cattle and sheep, sea ice prevented seal boats from sailing and there was no timber for fires. The freezing climate and lack of adequate diet had a severe effect on Greenlanders. In Osterbygd, there were some 225 deserted farms in 1500. Skeletons in the graveyards showed that the average height of the Greenlanders decreased by at least 12 cm over the first 200-year period of the Little Ice Age. A study of the chemistry of Viking teeth shows that between 1100 and 1400 there was a 1.5ºC drop in temperature.328,329 Examination of Viking cemeteries showed that with time, the graves became shallower as the permafrost returned.330 Greenland and Antarctica became stormier and windier at the start of the Little Ice Age, as shown by the increase in sea spray in ice cores.331 This was the death knell for the Vikings, who had greater difficulty in escaping from Greenland through the pack ice and in the stormier windier seas. Most did not escape and the colony of Greenland, once promoted by Eric the Red in the Medieval Warming, was no longer populated by the immigrants. Only the Inuit people survived.
The second phase of the Little Ice Age (1550–1850 AD) was even colder and more variable. In the middle of the 16th Century a very rapid change occurred. This change is reflected in vegetation. An upland blanket of peat in southern Scotland provides a vegetation and climate record over the last 5500 years and shows 210-year cycles of alternating wet-cool and warm climate with the coldest wettest time in the Little Ice Age during the Spörer Minimum (1450–1540 AD).332 This coincides with a solar cycle of 210 years in length, the DeVries-Suess Cycle.
The first half of the 16th Century in Europe appears to have been much warmer than the previous 150 years, which had seen a steady decline in temperatures after the Medieval Warm Period. During this early 16th Century warmth, people were able to bathe in the Rhine River in January. A brief warm period in the 1500s allowed the return of ships to Greenland, only to find that the stranded Viking population had starved and frozen to death.
However, this early 16th Century warmth was not to last and a rapid cooling occurred. The winter of 1564–1565 was long and bitter. It heralded many similar winters which brought hardship and social unrest throughout Europe. The next 150 to 200 years was the zenith of the Little Ice Age and temperatures were lower than any other period since the last major ice age.333 The impact of this sudden cooling in the middle of the 16th Century was widespread.334 Glaciers advanced rapidly in Greenland, Iceland, Scandinavia and the European Alps. Large areas of high latitude and alpine land were abandoned, snowfall was much higher and snow lay on the ground for many months longer than it does today. Many springs and summers were very cold and wet. Seasons became more variable between years and groups of years. European farmers tried to adapt by changing cropping practices for the shortened, less reliable growing season but there were many years of famine. Violent storms created havoc, flooding and loss of life with some areas along the Danish, German and Dutch coasts lost permanently to the sea. Contemporary painters recorded these scenes. Pieter Brueghel the Elder (1525–1569) started a snow scene genre which included biblical scenes, such as the Adoration of the Magi in a snowstorm!
Rapid climate changes were also recorded in Africa. In Ethiopia and Mauritania, permanent snow was reported on mountain peaks at levels where it does not occur today. The Niger River flooded Timbuktu at least 13 times yet there are no records of similar flooding before or since the mid 16th Century. In North America it was a similar story and European settlers reported exceptionally severe winters. From 1607–1608, Lake Superior’s ice persisted until mid summer.
If the air is cold, the ground beneath our feet cools. Periods of extreme cold coincided with the Sun’s weakest output of energy. Examination of temperature indicators in boreholes in Australia has given a 500-year record of temperature.335 The 17th Century was the coolest in this 500-year period, with warming in the 19th and 20th Centuries. The warming of Australia over the past five centuries is only about half that experienced by the continents of the Northern Hemisphere in the same period. This geothermal reconstruction agrees with tree ring evidence from Tasmania and New Zealand. Because Australia had no snow cover in the Little Ice Age, its borehole data is far more accurate than borehole data from areas in the Northern Hemisphere. More importantly, the Australian and South Pacific336 data shows that the Little Ice Age was global. This is contrary to the suggestion that the Little Ice Age was restricted to the Northern Hemisphere and was caused by a weakening in the Gulf Stream.337 Stalagmites in a cave in the Makapansgat Valley of South Africa show that the region was 1ºC cooler from 1300 to 1800 AD. The lowest temperatures recorded in South Africa were in the Maunder and Spörer Minima.338 Again it is clear that the Little Ice Age was global and not regional.
The Maunder Minimum (1645–1715 AD) was bitterly cold. In China from 1654 to 1676, orange groves that had existed for centuries in Kiangsi Province were abandoned. Cool climate oak forests appeared in Mauritania, suggesting that south of the Sahara Desert it was far cooler and wetter than now, and the water level in Lake Chad was about 4 metres higher than now. In 1676, the artist Abraham Hondius painted hunters pursuing a fox across the frozen Thames River of England. Ice fairs were held on the Thames, the last of them in 1813–1814 towards the end of the Little Ice Age. In 1684, the coast of the English Channel had a 5 km belt of ice. It was so cold in 1695 that ice blocked all the coast of Iceland in January and stayed for most of the year. Cod fishing was not possible, there was little hay and the only source of food was sheep and cattle.339 One observer in Switzerland in the early 1600s reported that a glacier was advancing daily as far as one could shoot a musket. Between 1695 and 1728, Orkney islanders in far northern Scotland saw Inuits paddling kayaks. One kayaker went as far south as the River Don near Aberdeen. Arctic sea ice had pushed these hunters, seals and cod south.
Famine in Europe killed millions between 1690 and 1700 AD and these were followed by famines in 1725 and 1816.340 With the eruption of Tambora in Indonesia on 10 April 1815, the situation was only exacerbated. The explosion was heard 850 km away and the top 1400 metres of the volcano was blasted into the air leaving a crater 6 km across and 1 km deep. The blast was equivalent to 60,000 Hiroshima-sized bombs. Tambora launched more than seven times the number of ash particles into the atmosphere than the more famous Krakatoa eruption of 1883. The Indonesian islands were plunged into darkness for two days. Most crops were destroyed by the ash fall and tsunamis. Nearly 10,000 islanders on Tambora were engulfed in ash, all vegetation on Lombok and Bali died and the epidemics and famine in the months following killed more than 80,000 islanders. Contemporary Chinese records show that at Hainan Island, 2000 km north of Tambora, the Sun disappeared. The combination of low temperatures, excessive rainfall and unseasonal frosts played havoc with subsistence farming. China experienced an exceptionally cold and stormy winter in 1816–1817 with disastrous crop failures.
The large volume of fine particles of dust filled the atmosphere in both hemispheres, reflected light and reflected heat, as did a monstrous volume of sulphuric acid droplets. Ash was trapped in the Greenland ice sheet. It was at this time that landscape artists such as J.M.W. Turner painted brilliant sunsets and stormy seas. The winter of 1815–1816 was known as “the year without a summer”. Three long cold periods ravaged Canada and the New England region of the USA. The first, in June, killed most crops. The second, in July, killed replanted crops and the third, in August, killed corn, potatoes, beans and vines. Severe cold and crop failures ranged from North America to the Ottoman Empire in the Middle East, into parts of North Africa and across Europe. Typhus epidemics followed the crop failures and the bubonic plague again appeared. The Rev. Ezra Styles, the president of Yale University, started keeping daily temperatures from 1779. The June 1816 measurements were the coldest thermometer measurement ever recorded in Connecticut, some 2.6ºC lower than the 1780–1968 long-term mean, and 1816 was the coldest year on record in the USA.
Europe was still recovering from the disruption brought on by the Napoleonic Wars, which took place during a period of cool wet years.341 The cold years of 1816–1817 created a food crisis and widespread unrest, especially in France. This drove immigration from Europe to the USA and American farmers from northern to warmer latitudes. Average temperatures in the UK were 2ºC lower and it rained or snowed almost every day. Prices on the London Grain Exchange skyrocketed. Crop failures in Bengal in 1816 resulted in famine which triggered a major outbreak of cholera. This spread from Bengal and was the world’s first cholera pandemic. It reached northwestern Europe, Russia and the eastern USA in the summer of 1832. At Lake Geneva, the poet Lord Byron and his guests Mary and Percy Shelley used the gloomy summer of 1816 to write. Mary Shelley wrote Frankenstein and Byron wrote Darkness.342 Tambora gives a pretty bleak picture into the effect of an equatorial volcanic eruption or a small asteroidal impact. It also provides a window into the effects of global cooling.
A tree ring study shows that growth in high-altitude European forests slowed because of the cold in the Little Ice Age. Elsewhere forests became stressed and were replaced by tundra.343 Between 1625 and 1720 in the Maunder Minimum, trees showed exceptionally narrow growth rings producing dense and strong wood. These properties may have enhanced the quality of the violins made by Stradivarius, who produced his most famous instruments between 1700 and 1720.344
Low clouds occur during cold times. In a remarkable study of clouds by a meteorologist who studied more than 6000 landscape paintings in galleries in Europe and North America painted from 1400 to 1967, a statistical analysis showed a slow increase in cloudiness between the early 15th and mid 16th Centuries (i.e. Spörer Minimum). Low clouds increased after 1550 and declined after 1850 (end of Little Ice Age). Summer in the 18th and 19th Centuries showed that 50 to 75% of the summer sky was covered with cloud345 (Maunder and Dalton Minima). Although artists surely took some licence with their subjects, none of the British paintings viewed showed a clear sky whereas some 12% of Mediterranean paintings showed a completely clear sky. The data showed an increase in cloudiness between 1400 and 1550 and then an abrupt further increase (more than 50%), especially in the abundance of low clouds. Cloudiness peaked in the 17th Century (Maunder Minimum).
Landslides form in colder times when the process of freezing and thawing moves unconsolidated material and in spring when unconsolidated material is destabilised by meltwater acting as a lubricant. Most major landslides in the Swiss Alps occurred in a cold period before the Roman Warming, the Dark Ages and the Little Ice Age.346
The most recent cool period, the Little Ice Age, and preceding climate changes are well recorded in ocean floor sediments off West Africa, Greenland ice cores, Swiss landslides, seafloor sediments from the North Atlantic Ocean, seafloor sediments from the Arabian Sea, cave stalagmites from Germany and Ireland, sea surface temperatures and plankton in the Sulu Sea.347 For example, the Sargasso Sea shows that sea surface temperature was about 1ºC lower than today in the Little Ice Age and about 1ºC warmer than now in the Medieval Warming.348 Life in lakes, fjords349 and oceans350 adapted to the colder climate of the Little Ice Age and the rapid climate variations. Sediments from volcanic crater lakes in Uganda show that the Little Ice Age in Africa had a number of cool and warm periods351 and periods of intense rainfall and drought.352 While Europe was cold and wet, tropical central Africa was cold and dry. Tropical South America also enjoyed a fluctuating and cooler drier climate in the Little Ice Age.353
While in the grip of the Little Ice Age, there were 10 eruptions from the Laki craters (Iceland) between June 1783 and February 1784. Not only was Europe covered in a dry sulphuric acid fog as a result, there was additional cooling and damage to vegetation.354,355,356 These eruptions created a cascade of events that led to record low levels of water in the Nile River in Africa. Unusual temperature and rainfall patterns peaked in 1783 causing below normal rainfall in most of the Nile source areas. Europe was colder, tree rings in Alaska and Siberia show stunted growth, and a lack of monsoons led to a reduction in cloud cover of the Sahel of Africa, the southern Arabian Peninsula and India.357
A study of Vermetid reefs off the Sicilian coast in the Mediterranean documented the history of sea surface temperature over the last few centuries.358 The Maunder Minimum and the Late 20th Century Warming could be seen as a chemical signature in the reefs.
During the Little Ice Age, Greenland was very cold and Antarctica was relatively warm. Between 1550 and 1700, melting of Greenland ice was common with 8% of the years experiencing melting and elevated summer temperatures.359 Although the Little Ice Age was global, the Antarctic Anomaly was apparent. Notwithstanding, the Little Ice Age was felt in the Southern Hemisphere. The transition from the Medieval Warming to the Little Ice Age at around 1300 in the South Pacific created social upheaval360 which was followed by famine, migration and depopulation.361
Ships’ logbooks provide a daily detailed insight on the weather and climate of the Little Ice Age.362,363,364 A study of more than 6000 logbooks ranging from Nelson’s Victory and Cook’s Endeavour to the humblest frigate provide a contemporary unified record of wind force, direction, precipitation and notes about the weather. Most records also show air pressure, air temperature and sea surface temperature. These logs show that the decades of the 1680s and 1690s were the coldest for 1000 years and that there was a surge in summer storms.365 This was in the Maunder Minimum (1645–1715 AD).
The popular belief was that hurricanes form in the east Atlantic Ocean and track westwards. It was a surprise when, in 2005, Hurricane Vince moved northeast and hit southern Spain and Portugal. For many, this was proof of unusual weather conditions derived from human emissions of CO2. However, the same happened in 1842, well before industrial emissions of CO2. The 100,000 Royal Navy logbooks from 1670 to 1850 are a goldmine of information as are the 900 logbooks of the East India Company covering 1780 to 1840. These can provide a global perspective (e.g. Robert FitzRoy’s two expeditions in HMS Beagle in the 1820s and 1830s with Charles Darwin), information on the Arctic, East and West Indies and the Mediterranean Sea (Horatio Nelson’s voyages) and information on the Pacific Ocean (Captain James Cook in the 1760s and 1770s).
The Little Ice Age was savage. It was global. Conditions changed from pleasant warmth to bitter cold in just two decades. This dramatic climate change was initiated by changes in solar activity, and the coldest periods in the Little Ice Age were when the Sun was relatively inactive (see Chapter 3).
The Little Ice Age brought famine, disease, death, depopulation, war and social disintegration. The previous cooling, the Dark Ages, did the same. Over the last 1000 years in Europe, there is a correlation between violent conflict, cold weather and precipitation.366,367 Cold times bring violence, war, depopulation and human misery.