How a flexible economy saved a nation during a period
of unpredictable climate

Excavations at the ancient farm of Hjalmarvik are providing detailed insights into the ways Icelanders adapted to changing climatic conditions. (Zach Zorich)
The walls of the trench are striped with orange peat ash, probably discarded when the hearth inside the house was cleaned. Although the crew has uncovered interesting whalebone carvings—some decorated with images and others that were used as gaming pieces—the most common items found in the trench are the discarded bones of the animals eaten by Hjalmarvik’s residents. Laboratory analysis of the bones has not yet begun, but at first glance it looks like most of the food they were eating came from the surrounding ocean.



Whalebone carvings are some of the most intriguing artifacts from Hjalmarvik. This semicircular carving (top) is a broken disk depicting a mythological animal. Two sides of a bone may possibly show a cross (middle) and writing (bottom). (Zach Zorich)
Near the top of the trench’s east wall, Ólafsson points out a gray stripe of volcanic ash that came from the 1477 eruption of a volcanic fissure named Veidivötn. This layer provides an easy way to date the latest part of the midden. The ash shows that the site was occupied throughout a period when Icelanders faced one of the greatest challenges to their survival—the Little Ice Age. Currently, an international group of archaeologists is excavating sites across the country in an effort to understand how Icelanders adapted to the colder climate. The project at Hjalmarvik and another excavation at a fishing station in the west called Gufuskálar are revealing how Icelanders changed the way they produced food so that they could survive what turned out to be centuries of long, cold winters.
In 1258, somewhere near the equator, a massive volcano erupted, ultimately lowering global temperatures. According to a study coauthored by Penn State University climatologist Michael Mann, average temperatures in the years after the eruption dropped between 3.6 and 4.5 degrees F, or about half as much as temperatures had dropped at the peak of the last major ice age, between 18,000 and 12,000 years ago. A group of scientists at the Institute of Arctic and Alpine Research in Colorado have identified the chain of events that followed the eruption, which they believe led to the long-term climate change of the Little Ice Age.
The chain of events began when volcanoes threw chemical compounds called sulfates into the atmosphere. According to Gifford Miller, the institute’s associate director and a professor of geology at the University of Colorado Boulder, the process continued as sulfates reflected sunlight back into space. The resulting lack of sunlight not only dropped the temperature in the atmosphere, it made the surface waters of the ocean colder. The colder ocean produced more sea ice, which spread out from the polar ice caps, cooling waters closer to the equator. In addition, the white surface of the ice reflected sunlight, further dropping temperatures. Miller says that although the sulfates would have fallen out of the atmosphere within two to four years, ocean temperatures would have taken 20 or 30 years to rebound. Sulfate levels in ice cores taken from glaciers in Greenland and Iceland show that additional eruptions at volcanoes in the tropics took place in 1268, 1275, and 1285, reinforcing the cooling effect. Because the effects of a changing climate are not felt evenly across the globe, the Little Ice Age began and ended at different times in different places. According to Miller, it started around 1258 in Iceland and lasted until about 1900.
Even by the standards of a nation on the edge of the Arctic Circle, Hjalmarvik is a cold place. The warm water that comes up from the Caribbean and keeps southern Iceland relatively warm doesn’t reach this area. Here, the cold water of the Arctic Ocean dominates the climate. On a sunny day in mid-June, the temperature was about 50 degrees, while it was about 10 degrees warmer in the capital city of Reykjavik.
Hjalmarvik seems to have been just one property within a much larger estate called Svalbard, which covered about 58 square miles of land. Most of Svalbard’s wealth came from growing grass to feed its herds of livestock, primarily cattle and sheep. No single farm could have made use of such a large amount of land, so smaller subordinate farms and workstations were built throughout the property to take advantage of pastures and other resources that were far from the main farm. To date, archaeologists have identified 17 of these. James Woollett, also of Laval University, is one of the project leaders looking at sites within Svalbard’s property, including Hjalmarvik, to understand how the farm functioned as a whole and how it changed over time.

A layer of fish bones roughly three feet thick runs for nearly a mile along the beach at Gufuskálar in western Iceland. The site was a fish processing station that provided dried cod for a robust international trade dating back to at least the 15th century. (Zach Zorich)
In 1988 Woollett was part of a team that excavated the midden at Svalbard. What that dig, as well as excavations at other sites on Svalbard’s property, revealed is that the people at the farm ate mostly mutton, beef, and a little pork in the middle of the thirteenth century, before the climate got colder. Woollett believes that the farmers at Svalbard figured out an ingenious strategy to adapt to the colder and less predictable climate as the Little Ice Age set in.

A few of many fish-drying huts sit a few hundred yards from the beach at Gufuskálar. The huts were made of lava rock, and provided a place to store dried cod before it was loaded onto ships and taken to Europe. (Zach Zorich)
At the same time, the farmers at Svalbard changed their herding strategy. The farm would have kept a few cows for dairying and a few horses for transportation, but almost all of the animals raised at Svalbard were sheep. According to Woollett, this was a good approach because sheep are hardier and require less fodder than pigs and cattle. The pastures in northeastern Iceland aren’t as productive as those in continental Europe, so the strategy at Svalbard seems to have been to raise a relatively small number of sheep on a large amount of land. “The land is pretty crappy, but there is a lot of it,” says Woollett, adding, “they’re not producing what you want to eat if you are an elite [i.e., beef], but it is a predictable and durable system.” A similar system persisted for centuries. Even after farmers began to use tractors in the early to mid-twentieth century and were making money from tourists who wanted to fish in their rivers, sheep herding remained the agricultural focus of the area’s farms.

The fishermen’s boats were dragged onto the beach at specific locations at the site of Gufuskálar. Lava rock on the beach shows evidence of the grooves created when boats were hauled ashore. (Zach Zorich)
Evidence of the cod trade comes from the site of Gufuskálar at the end of the Snaefelsnes peninsula in western Iceland. There, Lilja PálsdÓttir of the Icelandic Archaeological Institute is leading a project to uncover the remains of an enormous fish-processing site. Walking along the shoreline, PálsdÓttir points out a few places where grooves were worn into the rock from years of having boat keels dragged over them.
After hauling their boats on shore, fishermen would unload their catch and take the fish to be cleaned at workstations just off the rocky shoreline. The fish were gutted and their heads and part of their spines removed. The discarded bones of hundreds of years of activity now form a midden about three feet thick that extends for nearly a mile along the beach, testifying to the number of cod that were caught here. The fish would then have been taken back down to the beach, where they were washed and laid flat to dry on tables made of stacked lava rocks. After the fish were dried, they were piled inside a group of small huts, also made of lava rock, that sit a few hundred yards from the beach, to await transport. In 2009, when she first surveyed the drying huts, PálsdÓttir identified 154 of them, and takes them to be another indicator of how vast the fishing enterprise was and the impact it had on Iceland’s economy.


An iron knife blade (top) and fishhook (bottom) recovered from Gufuskálar were some of the tools of the fishermen’s trade. Until the 20th century, people fished from row boats using only line with baited hooks. (Zach Zorich)
In 1450, a volcano called Kuwae erupted in the South Pacific, again cooling the climate. Within 50 years, Kuwae was followed by three eruptions at other, so-far-unknown, locations, which compounded the cooling effect. In addition, 1450 happened to be the beginning point of a 90-yearlong period of low solar activity called the Spörer Minimum. This combination of events led to one of the coldest phases of the Little Ice Age.
During periods when the climate was too cold for grass to grow and sheep were dying off, marine fish gave the Icelanders something to eat and something to trade for grain from Europe. One of the worst periods in Iceland’s history occurred after the 1783 eruption at the fissures of Laki in the south-central part of the country. That eruption cooled the climate at a time when the country had not yet recovered from the 1707 smallpox epidemic that had killed as much as one-third of its population. “The agriculture just collapses, and cod becomes very, very important,” says PálsdÓttir. “It’s the main thing that keeps people alive.”
Fishing is still an important part of Iceland’s economy, and the industry is carefully managed to prevent overfishing. In 2011, more than $2 billion of marine products were exported. But now the country is faced with an entirely different type of climate change: The weather is warm and getting warmer.
Zach Zorich is a senior editor at ARCHAEOLOGY.
1 comMENTS:
Beautiful.
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