Winter severity indices for Europe are compared and evaluated. New values are presented for the p... more Winter severity indices for Europe are compared and evaluated. New values are presented for the period 1220–1420 A.D. Overall, the data show long time scale cooling from c. 1200 to c. 1340, warming to c. 1510 and then cooling into the main Little Ice Age cold period of the 17th century.
The loss of the Norse Western Settlement in Greenland around the mid-fourteenth century has long ... more The loss of the Norse Western Settlement in Greenland around the mid-fourteenth century has long been taken as a prime example of the impact of changing climate on human populations. This study employs an interdisciplinary approach combining historical documents, detailed archaeological investigations, and a high-resolution proxy climate record from the Greenland Ice Sheet Project 2 (GISP2) to investigate possible causes for the end of this settlement. Historical climate records, mainly from Iceland, contain evidence for lowered temperatures and severe weather in the north Atlantic region around the mid-fourteenth century. Archaeological, palaeoecological and historical data specifically concerning the Western Settlement suggest that Norse living conditions left little buffer for unseasonable climate, and provide evidence for a sudden and catastrophic end around the mid-fourteenth century. Isotopic data from the GISP2 ice core provide annual- and seasonal-scale proxy-temperature sig...
Research into the climate of the Middle Ages has relied heavily upon data provided by compilation... more Research into the climate of the Middle Ages has relied heavily upon data provided by compilations of references to weather and related phenomena extracted from a variety of historical texts and source documents. These compilations, produced from 1858 onwards, have generally neglected the essential need for source validation. While a considerable amount of reliable and useful information about medieval climate is to be found in documentary sources, it occurs together with material which is spurious, inaccurate, or whose reliability cannot be properly authenticated. Because they were, for the most part, scientists, unfamiliar with historical methodology and techniques of source analysis, the authors of the compilations were either unaware of the problematic character of their sources, or ignorant of the techniques developed by historians for dealing with them. The material included in the compilations must be regarded as suspect until its authenticity has been checked by validating individual sources. Unless this is done, a misleadin~ picture of the climate of the Middle Ages may emerze from uncritical use of the compilations. In particular, the climate may appear to have been more extreme than authentic sources alone would suggest. * See Appendix at end. ** "The cold was so extreme, and everything so parched from the dryness of winter that the rivers seemed not merely to be iced over on the surface but entirely turned to ice. It was extraordinary." *** "The winter is so harsh that all the rivers in Flanders and in Germany are completely frozen."
February 2000 lined. In particular, the times of exploration and settlement for Iceland, Greenlan... more February 2000 lined. In particular, the times of exploration and settlement for Iceland, Greenland, and 'Vinland' are considered. The main focus will be on three separate lines of evidence. These are: documentary written records, mainly from Iceland; isotopic ice-core records from the Greenland ice sheet; and marine-sediment cores from Nansen Fjord, Greenland. These proxy climate records provide information about important factors such as relative temperature and sea-ice in the years around AD 800-1 100 and thereafter. Historical background The Viking Age The 'Viking Age' traditionally refers to the period from around c. AD 800 to 1100, when people of Scandinavian origin, primarily from modern-day Norway, Sweden and Denmark, left their homes and travelled far, to raid and plunder, but also to trade and to settle.
Systematic temperature observations were not undertaken in Norway until the early 19th century, a... more Systematic temperature observations were not undertaken in Norway until the early 19th century, and even then only sporadically. Climate-proxy data may be used to reconstruct temperatures before this period, but until now there have not been any climate proxies available for late winter. This situation has recently changed, as a diary containing historical ice break-up data from a farm near lake Randsfjord in southeastern Norway has been discovered. These data, together with observations from lake Mjøsa in the same region, make it possible to reconstruct temperature back to 1758. The reconstructed series, combined with instrumental series from the area near the lake, were merged into one composite time series covering the period 1758–2006. The lowest temperatures are seen during the Dalton sunspot minimum in the early 19th century. The 20th century was 1.3˚C warmer than the 19th century, whereas the 19th century was 0.4˚C warmer than the last 43 years of the 18th century. During the...
The Mývatn area in northeast Iceland has been occupied by farming communities since the arrival o... more The Mývatn area in northeast Iceland has been occupied by farming communities since the arrival of Viking Age settlers in the late ninth century. Despite its inland location and relatively high elevation, this lake basin was affected by continuous human occupation through periods of harsh climate, volcanic eruptions, epidemics, and world system impacts. Mývatn’s residents have practised farming, fishing, egg-collecting, and hunting activities for over a millennium. They managed the landscape and its resources with the use of traditional knowledge, which included the story of the troll woman, Kraka, who lived in a cave in the mountain Blafjall (“Blue Mountain”). The story of Kraka and the river Kraka that bears her name provides a striking metaphor for the landscape history including water resources and environmental changes the agricultural community sustained over time.
China is distinguished by a prominent monsoonal climate with large variability. Because of the lo... more China is distinguished by a prominent monsoonal climate with large variability. Because of the long history of Chinese civilization, there are abundant and well-dated documentary records for climate reconstruction. Here we present the documentarybased reconstructions on the series of temperature and dry-wet index in monsoon China for the past 2000 years. We focus on the data sources, the derivation of proxies and the methodologies for quantifying the descriptive records, especially on the principal approach based on various information recorded in different documentary sources, and the synthesis approaches for assembling several separate data derived from different documentary sources and different periods respectively. This will be helpful for using the reconstructed data in study of climate change and comparison to instrumental data.
1 The Icelandic language contains the letters ð (upper case Ð) pronounced like the "th" in "cloth... more 1 The Icelandic language contains the letters ð (upper case Ð) pronounced like the "th" in "clothe" and þ (upper case Þ) pronounced like the "th" in "thing". Unless in a quotation or a personal name, the letter "Þ" is transliterated to "Th" throughout the paper.
This project has centered on the Lake Myvatn area of northeastern Iceland. In spite of severe ero... more This project has centered on the Lake Myvatn area of northeastern Iceland. In spite of severe erosion problems, the Myvatn economy has been largely sustainable since the time when Iceland was first settled in the late ninth century. Until the early part of the twentieth century, the inhabitants of the region lived almost entirely on the proceeds of the land by farming, fishing for trout, and collecting the eggs of wild birds. In recent times, tourism has become an extremely important part of the economy. This brings needed revenue but raises conservation issues in what is a very fragile ecosystem. The interplay between the hydrology and geology of the area has formed a unique landscape characterised by an abundance of pseudo-craters and curious lava formations and an ecosystem that is unparalleled in Iceland. In the Myvatn area most resources are directly connected to water. The complex food web and biogeochemistry of the lake has created unique wildlife resources on which people de...
When thinking of Iceland, two specific types of ice come to mind: the ice that is formed on the m... more When thinking of Iceland, two specific types of ice come to mind: the ice that is formed on the many glaciers in the country, and the sea ice that is brought to the coasts by winds and ocean currents. Because of space constraints in this volume, the discussion here will focus entirely on the phenomenon of sea ice. This paper is not concerned with ice as a scientific phenomenon, but with the image of sea ice as presented in a variety of different narrative genres concerning Iceland. However, a few words of elucidation will set the stage for the discussion. Ice on the sea is formed in two main ways. Either by being broken off in the form of ice bergs from calving glaciers, or else it may form directly on the surface of the sea as frozen seawater. Most of the ice reaching Iceland is of the latter kind, and arrives by way of the East Greenland current. It is the northern, northwestern, and eastern coasts of Iceland which are most frequently affected, and, in the past, it occurred most o...
This presentation will focus on climate impacts of hay and grass harvesting in the Mývatn area in... more This presentation will focus on climate impacts of hay and grass harvesting in the Mývatn area in the northeastern highlands of Iceland. Mývatn means “Midge Lake” and refers to the flies or midges, of vital importance for the local ecosystem, providing food for fish and waterbirds. Until the early part of the twentieth century, the inhabitants of the area lived almost entirely on the proceeds of the land by farming, fishing for trout, and collecting the eggs of wild birds. With its North Atlantic location, marginal for agriculture, grass was the only viable crop in Iceland, and the economy focused primarily on animal husbandry until comparatively recent times. Thus, the success or failure of the all-important grass crop, coupled with winter rangeland grazing, was the one aspect of the economy on which all else rested. The successful harvesting of hay was thus the farmers’ most important annual task. If there was not enough hay in the winter to feed the livestock they could die, and ...
In this presentation, documentary sources of climate change will be described and evaluated, and ... more In this presentation, documentary sources of climate change will be described and evaluated, and the information gathered from them will be used to cast light on variations in the climate of Iceland over the last 1000 years or so. Prior to AD 1600 the data are fairly sporadic, but after that time it is possible to re-construct temperature and sea-ice indices. A scrutiny of the sources indicates that there has been a great deal of climatic variability from early settlement times to the present day. From ca. 1640 to ca. 1680 there appears to have been little sea ice off Iceland’s coasts. During the period 1600 to 1850, the decades with most ice present were probably the 1780s, early 1800s and the 1830s. From 1840 to 1855 there was virtually no ice off the coasts. From that time to 1860 there was frequent ice again, although the incidence does not seem to have been as heavy as in the earlier part of the century. Further clusters of sea-ice years occurred again from ca. 1864 to 1872. Se...
In 1997 the National Science Foundation Arctic System Science (ARCSS) program launched the Human ... more In 1997 the National Science Foundation Arctic System Science (ARCSS) program launched the Human Dimensions of the Arctic System (HARC) initiative. Its goal is to “understand the dynamics of linkages between human populations and the biological and physical environment of the Arctic, at scales ranging from local to global.” Since its inception in 1989, ARCSS had focused on the physical and biological aspects of the Arctic system. The HARC initiative was intended to help expand the scope of ARCSS to include more work on the place of humans within that system. Taken together, HARC projects offer the most direct link between ARCSS research and society, providing relevant information on topics of importance to Arctic communities and the world at large. HARC developed through projects proposed in response to the new initiative and through the incorporation of existing projects that had a clear focus on human dimensions. These projects had in common the involvement of several disciplines,...
In olden days there was a troll woman named Kráka who lived in Bláhvammur by Bláfjall. She lived ... more In olden days there was a troll woman named Kráka who lived in Bláhvammur by Bláfjall. She lived in a cave the remains of which can still be seen. It is so high up in the crags of Bláhvammur that it is inaccessible to all human beings. Kráka was extremely evil and she constantly attacked the sheep belonging to the people of Mývatn and did great damage in the form of seizing sheep and killing humans (Kráka tröllskessa in Þjóðsagnabókin Sýnisbók íslenzkra þjóðsagnasafna. Sigurður Nordal tók saman. Translation Astrid Ogilvie). Abstract: The Lake Mývatn area in northeast Iceland has been occupied by farming communities since the arrival of Viking Age settlers in the late 9 th century. Despite its inland location and relatively high elevation, this lake basin has seen continuous human occupation through periods of harsh climate, volcanic eruptions, epidemics, and world system impacts. Mývatn residents have conducted farming, fishing, egg collecting, and hunting activities for over a mill...
Winter severity indices for Europe are compared and evaluated. New values are presented for the p... more Winter severity indices for Europe are compared and evaluated. New values are presented for the period 1220–1420 A.D. Overall, the data show long time scale cooling from c. 1200 to c. 1340, warming to c. 1510 and then cooling into the main Little Ice Age cold period of the 17th century.
The loss of the Norse Western Settlement in Greenland around the mid-fourteenth century has long ... more The loss of the Norse Western Settlement in Greenland around the mid-fourteenth century has long been taken as a prime example of the impact of changing climate on human populations. This study employs an interdisciplinary approach combining historical documents, detailed archaeological investigations, and a high-resolution proxy climate record from the Greenland Ice Sheet Project 2 (GISP2) to investigate possible causes for the end of this settlement. Historical climate records, mainly from Iceland, contain evidence for lowered temperatures and severe weather in the north Atlantic region around the mid-fourteenth century. Archaeological, palaeoecological and historical data specifically concerning the Western Settlement suggest that Norse living conditions left little buffer for unseasonable climate, and provide evidence for a sudden and catastrophic end around the mid-fourteenth century. Isotopic data from the GISP2 ice core provide annual- and seasonal-scale proxy-temperature sig...
Research into the climate of the Middle Ages has relied heavily upon data provided by compilation... more Research into the climate of the Middle Ages has relied heavily upon data provided by compilations of references to weather and related phenomena extracted from a variety of historical texts and source documents. These compilations, produced from 1858 onwards, have generally neglected the essential need for source validation. While a considerable amount of reliable and useful information about medieval climate is to be found in documentary sources, it occurs together with material which is spurious, inaccurate, or whose reliability cannot be properly authenticated. Because they were, for the most part, scientists, unfamiliar with historical methodology and techniques of source analysis, the authors of the compilations were either unaware of the problematic character of their sources, or ignorant of the techniques developed by historians for dealing with them. The material included in the compilations must be regarded as suspect until its authenticity has been checked by validating individual sources. Unless this is done, a misleadin~ picture of the climate of the Middle Ages may emerze from uncritical use of the compilations. In particular, the climate may appear to have been more extreme than authentic sources alone would suggest. * See Appendix at end. ** "The cold was so extreme, and everything so parched from the dryness of winter that the rivers seemed not merely to be iced over on the surface but entirely turned to ice. It was extraordinary." *** "The winter is so harsh that all the rivers in Flanders and in Germany are completely frozen."
February 2000 lined. In particular, the times of exploration and settlement for Iceland, Greenlan... more February 2000 lined. In particular, the times of exploration and settlement for Iceland, Greenland, and 'Vinland' are considered. The main focus will be on three separate lines of evidence. These are: documentary written records, mainly from Iceland; isotopic ice-core records from the Greenland ice sheet; and marine-sediment cores from Nansen Fjord, Greenland. These proxy climate records provide information about important factors such as relative temperature and sea-ice in the years around AD 800-1 100 and thereafter. Historical background The Viking Age The 'Viking Age' traditionally refers to the period from around c. AD 800 to 1100, when people of Scandinavian origin, primarily from modern-day Norway, Sweden and Denmark, left their homes and travelled far, to raid and plunder, but also to trade and to settle.
Systematic temperature observations were not undertaken in Norway until the early 19th century, a... more Systematic temperature observations were not undertaken in Norway until the early 19th century, and even then only sporadically. Climate-proxy data may be used to reconstruct temperatures before this period, but until now there have not been any climate proxies available for late winter. This situation has recently changed, as a diary containing historical ice break-up data from a farm near lake Randsfjord in southeastern Norway has been discovered. These data, together with observations from lake Mjøsa in the same region, make it possible to reconstruct temperature back to 1758. The reconstructed series, combined with instrumental series from the area near the lake, were merged into one composite time series covering the period 1758–2006. The lowest temperatures are seen during the Dalton sunspot minimum in the early 19th century. The 20th century was 1.3˚C warmer than the 19th century, whereas the 19th century was 0.4˚C warmer than the last 43 years of the 18th century. During the...
The Mývatn area in northeast Iceland has been occupied by farming communities since the arrival o... more The Mývatn area in northeast Iceland has been occupied by farming communities since the arrival of Viking Age settlers in the late ninth century. Despite its inland location and relatively high elevation, this lake basin was affected by continuous human occupation through periods of harsh climate, volcanic eruptions, epidemics, and world system impacts. Mývatn’s residents have practised farming, fishing, egg-collecting, and hunting activities for over a millennium. They managed the landscape and its resources with the use of traditional knowledge, which included the story of the troll woman, Kraka, who lived in a cave in the mountain Blafjall (“Blue Mountain”). The story of Kraka and the river Kraka that bears her name provides a striking metaphor for the landscape history including water resources and environmental changes the agricultural community sustained over time.
China is distinguished by a prominent monsoonal climate with large variability. Because of the lo... more China is distinguished by a prominent monsoonal climate with large variability. Because of the long history of Chinese civilization, there are abundant and well-dated documentary records for climate reconstruction. Here we present the documentarybased reconstructions on the series of temperature and dry-wet index in monsoon China for the past 2000 years. We focus on the data sources, the derivation of proxies and the methodologies for quantifying the descriptive records, especially on the principal approach based on various information recorded in different documentary sources, and the synthesis approaches for assembling several separate data derived from different documentary sources and different periods respectively. This will be helpful for using the reconstructed data in study of climate change and comparison to instrumental data.
1 The Icelandic language contains the letters ð (upper case Ð) pronounced like the "th" in "cloth... more 1 The Icelandic language contains the letters ð (upper case Ð) pronounced like the "th" in "clothe" and þ (upper case Þ) pronounced like the "th" in "thing". Unless in a quotation or a personal name, the letter "Þ" is transliterated to "Th" throughout the paper.
This project has centered on the Lake Myvatn area of northeastern Iceland. In spite of severe ero... more This project has centered on the Lake Myvatn area of northeastern Iceland. In spite of severe erosion problems, the Myvatn economy has been largely sustainable since the time when Iceland was first settled in the late ninth century. Until the early part of the twentieth century, the inhabitants of the region lived almost entirely on the proceeds of the land by farming, fishing for trout, and collecting the eggs of wild birds. In recent times, tourism has become an extremely important part of the economy. This brings needed revenue but raises conservation issues in what is a very fragile ecosystem. The interplay between the hydrology and geology of the area has formed a unique landscape characterised by an abundance of pseudo-craters and curious lava formations and an ecosystem that is unparalleled in Iceland. In the Myvatn area most resources are directly connected to water. The complex food web and biogeochemistry of the lake has created unique wildlife resources on which people de...
When thinking of Iceland, two specific types of ice come to mind: the ice that is formed on the m... more When thinking of Iceland, two specific types of ice come to mind: the ice that is formed on the many glaciers in the country, and the sea ice that is brought to the coasts by winds and ocean currents. Because of space constraints in this volume, the discussion here will focus entirely on the phenomenon of sea ice. This paper is not concerned with ice as a scientific phenomenon, but with the image of sea ice as presented in a variety of different narrative genres concerning Iceland. However, a few words of elucidation will set the stage for the discussion. Ice on the sea is formed in two main ways. Either by being broken off in the form of ice bergs from calving glaciers, or else it may form directly on the surface of the sea as frozen seawater. Most of the ice reaching Iceland is of the latter kind, and arrives by way of the East Greenland current. It is the northern, northwestern, and eastern coasts of Iceland which are most frequently affected, and, in the past, it occurred most o...
This presentation will focus on climate impacts of hay and grass harvesting in the Mývatn area in... more This presentation will focus on climate impacts of hay and grass harvesting in the Mývatn area in the northeastern highlands of Iceland. Mývatn means “Midge Lake” and refers to the flies or midges, of vital importance for the local ecosystem, providing food for fish and waterbirds. Until the early part of the twentieth century, the inhabitants of the area lived almost entirely on the proceeds of the land by farming, fishing for trout, and collecting the eggs of wild birds. With its North Atlantic location, marginal for agriculture, grass was the only viable crop in Iceland, and the economy focused primarily on animal husbandry until comparatively recent times. Thus, the success or failure of the all-important grass crop, coupled with winter rangeland grazing, was the one aspect of the economy on which all else rested. The successful harvesting of hay was thus the farmers’ most important annual task. If there was not enough hay in the winter to feed the livestock they could die, and ...
In this presentation, documentary sources of climate change will be described and evaluated, and ... more In this presentation, documentary sources of climate change will be described and evaluated, and the information gathered from them will be used to cast light on variations in the climate of Iceland over the last 1000 years or so. Prior to AD 1600 the data are fairly sporadic, but after that time it is possible to re-construct temperature and sea-ice indices. A scrutiny of the sources indicates that there has been a great deal of climatic variability from early settlement times to the present day. From ca. 1640 to ca. 1680 there appears to have been little sea ice off Iceland’s coasts. During the period 1600 to 1850, the decades with most ice present were probably the 1780s, early 1800s and the 1830s. From 1840 to 1855 there was virtually no ice off the coasts. From that time to 1860 there was frequent ice again, although the incidence does not seem to have been as heavy as in the earlier part of the century. Further clusters of sea-ice years occurred again from ca. 1864 to 1872. Se...
In 1997 the National Science Foundation Arctic System Science (ARCSS) program launched the Human ... more In 1997 the National Science Foundation Arctic System Science (ARCSS) program launched the Human Dimensions of the Arctic System (HARC) initiative. Its goal is to “understand the dynamics of linkages between human populations and the biological and physical environment of the Arctic, at scales ranging from local to global.” Since its inception in 1989, ARCSS had focused on the physical and biological aspects of the Arctic system. The HARC initiative was intended to help expand the scope of ARCSS to include more work on the place of humans within that system. Taken together, HARC projects offer the most direct link between ARCSS research and society, providing relevant information on topics of importance to Arctic communities and the world at large. HARC developed through projects proposed in response to the new initiative and through the incorporation of existing projects that had a clear focus on human dimensions. These projects had in common the involvement of several disciplines,...
In olden days there was a troll woman named Kráka who lived in Bláhvammur by Bláfjall. She lived ... more In olden days there was a troll woman named Kráka who lived in Bláhvammur by Bláfjall. She lived in a cave the remains of which can still be seen. It is so high up in the crags of Bláhvammur that it is inaccessible to all human beings. Kráka was extremely evil and she constantly attacked the sheep belonging to the people of Mývatn and did great damage in the form of seizing sheep and killing humans (Kráka tröllskessa in Þjóðsagnabókin Sýnisbók íslenzkra þjóðsagnasafna. Sigurður Nordal tók saman. Translation Astrid Ogilvie). Abstract: The Lake Mývatn area in northeast Iceland has been occupied by farming communities since the arrival of Viking Age settlers in the late 9 th century. Despite its inland location and relatively high elevation, this lake basin has seen continuous human occupation through periods of harsh climate, volcanic eruptions, epidemics, and world system impacts. Mývatn residents have conducted farming, fishing, egg collecting, and hunting activities for over a mill...
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