Frozen: Britain's Little Ice Age

Today, this period of weather is often associated with a 200-year timeframe stretching from the mid-17th to mid-19th centuries. But the climate had begun changing more than 350 years before John Evelyn described stranded ships in the frozen Thames – and the result wasn’t always extreme cold.

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A period of unusually warm, mostly dry, summers was brought to an abrupt end in 1315 when an unprecedented deluge began shortly after Easter. Sheets of rain descended on the sodden countryside. Freshly ploughed fields became shallow lakes. Corn and oat crops were decimated. Preachers declared that the Lord was angry and that divine vengeance had descended on the land.

With vast rainstorms sweeping across the country, livestock perished by the thousand. Only pigs flourished in the wet, but the herds were decimated when people turned from cereal to pork. The ‘great dying of beasts’ persisted into the 1320s, causing a severe shortage of manure.

As food became increasingly scarce (the bishop of Winchester’s lucrative grain mill, we’re told, “did not grind for half a year on account of the flood”), the consequences for England’s peasants were catastrophic. Tens of thousands died of starvation and famine-related diseases. The suffering continued for seven years before more normal harvests brought some relief.

It was at this moment of death and tumult that the Little Ice Age dawned across the world. Temperatures fell globally by about 0.60C relative to the average temperature between 1000 and 2000, although there were brief intervals where it was colder still. As a result, stable climatic systems were disrupted as extreme weather events – storms, weeks of rain and long drought cycles, as well as unrelenting cold – became commonplace.

Global cooling

A glacial geologist, François Matthes, first employed the term ‘Little Ice Age’ in 1939. He used it in an informal way, but, as these usages often do, it became a rigidly defined period in the climatic literature, beginning around 1300 and ending shortly after Victoria ascended the British throne in 1837. This chronology has been hotly debated in recent years, but one fact is widely accepted: the pendulum of climate change rarely paused during this period, with grievous economic consequences. Fluctuations in grain prices are an oft-quoted barometer of cold summers and, during the Little Ice Age, prices oscillated wildly – to as much as 88 per cent above normal levels in hungry years.

Fields turned into shallow lakes. Corn and oat crops were decimated. Preachers declared that the Lord was angry

As to why this global cooling occurred, nobody knows for certain – but scientists have identified three possible culprits over the years. The first is the seesaw of atmospheric pressure that links a prevalent high over the Azores and a low over Iceland. When pressure is high over Portugal and the Azores, and low over Iceland, winter temperatures are mild and rainfall is plentiful in northern Europe. Flip the pressure gradient, however, and temperatures fall dramatically.

The second potential culprit is the sun. Until recently, many scientists believed that a dramatic reduction in sunspot activity could have contributed to falling temperatures. We know that sunspots became rare in the 17th century – and that this phenomenon coincides with a dimming of the sun and a reduction of solar energy reaching Earth. However, the very latest research suggests that variations in solar activity play only a small role in the Earth’s climate.

Sophisticated climatic modelling and studies of periods of volcanic activity have added a third potential villain to the climatic mix. In 1257, a volcanic eruption of Mount Samalas, in what is now Indonesia, released massive amounts of volcanic sulphate particles into the atmosphere. Both human records and tree-ring samples show widespread summer cooling over the northern hemisphere in the years following the eruption – with terrible results. In London alone, up to 20,000 people perished from famine in the ensuing food crisis; in St Albans, the dead lay rotting in pigsties, on dunghills and in the muddy streets.

The onset of the Little Ice Age may be linked to an unusual 50-year period when four large volcanic eruptions such as this sent enormous quantities of volcanic ash into the atmosphere, devastating subsistence farming.

Such jolts to the world’s climatic network sent temperatures tumbling. But they also had the opposite effect, sparking heatwaves and dry winds. And it was at the height of the Little Ice Age that London suffered its most notorious fire.

In 1665, bubonic plague killed at least 57,000 people, but subsided during the cold winter of 1666. An intensely hot summer followed, turning the city into a tinder box. On 2 September 1666, during a period of dry north-easterly winds, fire broke out in the royal baker’s house during the small hours. The blaze spread rapidly, soon enveloping the first of numerous churches burned to the ground. London’s lord mayor distinguished himself by observing that it was nothing: “Pish, a woman might piss it out,” he declared. He was delusional. Diarist Samuel Pepys described the blaze “as only one entire arch of fire of above a mile long A horrid noise the flames made, and the crackling of houses at their ruin.” The destruction wrought by the Great Fire of London was epochal: 13,200 houses were destroyed in more than 400 streets or courts; 100,000 people were rendered homeless out of a population of 600,000.

No one blamed the north-easterly winds and dry heat for the disaster. Instead, the catastrophe was placed at the feet of the Lord. The 10th of October was proclaimed a Day of Humiliation to crave God’s forgiveness “that it would please him to pardon the crying sins of the nation”.

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Death and destruction

But God, it seems, wasn’t listening. Throughout the 17th century, Britain was battered by a succession of intense gales – ones that, as the residents of the Culbin estate in north-eastern Scotland were to discover – visited death and destruction on rich and poor alike.

Culbin was a thriving estate during the 17th century, protected by coastal sand dunes. The local farmers grew wheat and a form of barley in a sheltered location teeming with salmon. And as a sign of his growing prosperity, the local laird, Alexander of the Kinnaird family, built himself an imposing mansion.

Yet, no sooner was the mansion completed, in 1694, than a savage northerly gale burst from the North Sea onto the 1500-hectare estate. For 30 hours, storm winds and huge waves tore at the protective coastal sand dunes. Smothering clouds of dust and sand cascaded onto the sheltered fields inland and overwhelmed croft and mansion alike. The next day, nothing could be seen of 16 farms, all buried under 30 metres of loose sand dune. As for the laird, he became a pauper overnight. Nineteenth-century visitors found themselves walking on “a great sea of sand rising as it were in tumultuous billows”. Thick stands of Scots and Corsican pines planted in the 1920s now mantle the dunes – Britain’s largest coastal forest.

The great storm

The gale that battered Culbin was truly ferocious but not even that could rival the great storm that swept through southern England on 7 December 1703. When the author Daniel Defoe consulted his barometer that morning, it was so low that he assumed his children had fiddled with it. He was wrong. Within hours, hurricane-force winds were cascading tiles through London streets and killing passers-by. Some 2,000 chimneys collapsed; Westminster Abbey’s lead roof blew off. Defoe and his family cowered at home “rather than to meet most certain destruction in the open garden”. Enormous waves battered the ornate and newly constructed Eddystone lighthouse off Plymouth. The keepers and their fellow workers perished when the structure toppled.

Bitterly cold winters continued until the 1730s, when there were eight winters as mild as those of the 20th century. But the cold returned with a vengeance after 1739, when “much corn, and the greatest part of barley was lost”, and English grain prices rose by 23.6 per cent above the average.

Mount Tambora’s eruption in south-east Asia helped bring besieging cold to Britain in 1816, the ‘Year Without Summer’

As ever, it was the poor who suffered most. Few could afford coal or firewood. They shivered, huddled together in their hovels and huts, and sometimes froze to death. The London Advertiser wrote that "such swarms of miserable objects as now fill our streets are shocking to behold". Many were driven from parish to parish without any public relief. Edmund Burtt, an English gentleman travelling in Scotland in 1741, commented on young children "miserable objects indeed… mostly overrun with… distemper [diarrhea]".

For all the intense suffering, throughout the 17th and 18th centuries an agricultural revolution slowly but surely gave Britain the tools to better withstand the buffeting of its erratic climate. The population no longer depended on subsistence agriculture, and enclosure policies created larger farms and fields, where landlords combined cereals and stockbreeding. They planted cold-resistant crops – using fodder crops like clover to keep their beasts fat during the winter – and experimented with selective breeding of cattle and sheep. One landlord, Viscount ‘Turnip’ Townshend, rotated turnips with wheat and barley to feed his animals.

Just as critical to Europe’s growing ability to meet the challenges of the intense cold was the growth in global trade networks. These allowed grain to be exported and imported across the continent and for raw materials to be sourced from distant lands.

At the end of the 17th century, the two most prominent players on the global stage were England and the Netherlands. During the coldest snap of the Little Ice Age, both countries extended their reach around the world through conquest and expanding trade networks – not to mention utterly ruthless political subjugation.

Yet for all their growing wealth and influence, they weren't totally shielded from the destructive impact of the Little Ice Age. The eruption of Mount Tambora in southeast Asia in 1815 was part of a renewed burst of volcanic activity that brought besieging cold to Britain and much of western Europe. The following year – the 'Year without a Summer', when Mary Shelley came up with the idea for Frankenstein while sheltering from inclement weather – is often said to have marked the end of the Little Ice Age. However the cold persisted into 1892, when hundreds of Londoners died of exposure.

The Thames froze for the last time in 1895, and there has been consistent warming ever since. The cause is easy to discern – an inexorable rise in the use of fossil fuels such as coal, which darkened London skies and polluted the atmosphere with ever-rising greenhouse gasses.

But, while human activity can affect the climate, one cannot simply invoke the climate as the ‘cause’ of human events, large or small. Relationships between the weather and the economic, political and social systems that people use to structure their lives are complex, sometimes even counterintuitive. This is true today – and it was certainly true of Britain during the Little Ice Age.

Brian Fagan is distinguished emeritus professor of anthropology at the University of California, Santa Barbara. A revised version of his book The Little Ice Age: How Climate Made History was published by Basic Books in December 2019

This article was first published in the February 2020 edition of BBC History Magazine