The "Little Ice Age" (LIA) is possibly the best-documented climatic anomaly of the past... more The "Little Ice Age" (LIA) is possibly the best-documented climatic anomaly of the past. A wide range of datasets portrays a harsh climate that worsened living conditions, primarily in terms of cooler temperatures, for people across Europe sometime during the last millennium. Regardless of the vast amount of data covering the LIA, there is presently no consensus concerning its spatial
Arctic glaciers are currently undergoing major changes, but accurate knowledge about how they hav... more Arctic glaciers are currently undergoing major changes, but accurate knowledge about how they have varied continuously during the Holocene (<11 700 years) is still scarce. Here we present a new glacier record from Austre Okstindbreen in Nordland, northern Norway. This continuous reconstruction is based on a number of short and long cores collected from several downstream basins, which have been
The area north of the Kjosen fjord on the Lyngen Peninsula is mapped focused on glacial geomorpho... more The area north of the Kjosen fjord on the Lyngen Peninsula is mapped focused on glacial geomorphological features, and 13 cirque glaciers and their catchments are in- vestigated in detail. The four lakes Aspevatnet (Holocene glacier fluctuations), Barhei- vatnet (bio-proxy lake), Elvejordsvatnet (Holocene glacier fluctuations) and Trollvat- net (early deglaciation, Holocene slope processes) are investigated and bathymetric maps produced. Based
A record of Holocene snow-avalanche activity has been reconstructed from the presence of coarse (... more A record of Holocene snow-avalanche activity has been reconstructed from the presence of coarse (>1 mm) minerogenic particles in lake sediment cores retrieved from Vanndalsvatnet in western Norway. At this site, snow avalanches bring minerogenic debris and macroscopic plant remains from the adjacent valley side south of the lake onto the lake ice. When the lake ice melts during late
Magnetic properties of sediments retrieved from a small lake in northern Norway spanning the last... more Magnetic properties of sediments retrieved from a small lake in northern Norway spanning the last ∼14500 cal. years have been analyzed in detail. The high-resolution core, with its ability to detect sub-centurial variability, records the rapid retreat of the Fennoscandian Ice Sheet (FIS) in northern Lyngen, and subsequently, the establishment of a stable Allerød to Younger Dryas watershed. From early
Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna ... more Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna Peninsula in Hardanger, western Norway. By combining the position of marginal moraines with AMS radiocarbon dated glacier-meltwater induced sediments in proglacial lakes draining northern Folgefonna, a continuous high-resolution record of variations in glacier size and equilibrium-line altitudes (ELAs) during the Lateglacial and early Holocene
During the Lateglacial and early Holocene, abrupt, millennial-scale climatic variations are recor... more During the Lateglacial and early Holocene, abrupt, millennial-scale climatic variations are recorded in a wide range of high-resolution proxy records from marine and terrestrial archives in NW Europe. Our review of the evidence for these rapid climate events do not show an apparent link to possible forcing factors such as long-term, orbitally induced variations in solar radiation, short-term variations in
Based on an exponential relationship between winter precipitation as snow and summer temperature ... more Based on an exponential relationship between winter precipitation as snow and summer temperature at the equilibrium-line altitude (ELA) on modern Norwegian glaciers, it is possible to reconstruct former variations in winter precipitation by combining reconstructed ELAs with independent proxies for summer temperature. Glaciers respond mainly to changes in summer temperature and winter precipitation. By using the exponential relationship between summer
Variations in the North Atlantic Oscillation (NAO) index are reflected in glacier mass balance re... more Variations in the North Atlantic Oscillation (NAO) index are reflected in glacier mass balance records in western Scandinavia. The NAO index is best correlated with the net mass balance on maritime glaciers in southern Norway. Holocene glacier variations of maritime glaciers in western Scandinavia may therefore reflect winter precipitation changes and thus be a proxy for winter climate variability in
Variations in the magnetic signal (MS, SIRM, ARM, S-0.3T) in a high-resolution lacustrine record ... more Variations in the magnetic signal (MS, SIRM, ARM, S-0.3T) in a high-resolution lacustrine record from a small lake in northern Norway (Lyngen) spanning the last 14.500 years have been examined in detail. Our main objective has been (1) to discriminate and identify different sediment phase-changes recorded in this lake archive, and (2) to compare these changes with a broader climatic
The climate gradients over southern Norway are some of the strongest in the world. Generally, the... more The climate gradients over southern Norway are some of the strongest in the world. Generally, the climate change from a strong, maritime climate regime in western Norway to a continental climate regime east of the main watershed less than 150 km from the coast. Four glacier reconstructions have been obtained along this climatic gradient using proglacial terrestrial and lacustrine sites. Modern meteorological data show that the winter climate in western Norway is strongly modulated by changes in the pressure-field over the North-Atlantic. This is best expressed by variations in winter precipitation, where the North Atlantic Oscillation (NAO) index can explain more than 50% of the total precipitation variability. By using a well-established relationship between the summer temperature and winter precipitation at the equilibrium-line altitude of Norwegian glaciers and using independent records of summer temperature fluctuations, the ELA-variations and inferred winter precipitation across the west-to-east transect have been investigated. The regional analyses show that increased precipitation on the west coast also can be detected at the continental glaciers, however, with less amplutude. This shows that the precipitation changes detected on the maritime glaciers are mainly controlled by changes in the atmospheric circulation over the North Atlantic region. It is concluded that low-frequency changes in the strength of North Atlantic winter circulation have occurred during the Holocene.
We study the fracture roughness exponent zeta in (1) the two-dimensional fuse model with disorder... more We study the fracture roughness exponent zeta in (1) the two-dimensional fuse model with disorder in the burn-out thresholds, (2) the fuse model with disorder in the conductances, (3) the fuse model with breaking probability proportional to the current the bonds carry to a power eta. In addition, we have measured the correlation length exponent of the three-dimensional fuse model
The "Little Ice Age" (LIA) is possibly the best-documented climatic anomaly of the past... more The "Little Ice Age" (LIA) is possibly the best-documented climatic anomaly of the past. A wide range of datasets portrays a harsh climate that worsened living conditions, primarily in terms of cooler temperatures, for people across Europe sometime during the last millennium. Regardless of the vast amount of data covering the LIA, there is presently no consensus concerning its spatial
Arctic glaciers are currently undergoing major changes, but accurate knowledge about how they hav... more Arctic glaciers are currently undergoing major changes, but accurate knowledge about how they have varied continuously during the Holocene (<11 700 years) is still scarce. Here we present a new glacier record from Austre Okstindbreen in Nordland, northern Norway. This continuous reconstruction is based on a number of short and long cores collected from several downstream basins, which have been
The area north of the Kjosen fjord on the Lyngen Peninsula is mapped focused on glacial geomorpho... more The area north of the Kjosen fjord on the Lyngen Peninsula is mapped focused on glacial geomorphological features, and 13 cirque glaciers and their catchments are in- vestigated in detail. The four lakes Aspevatnet (Holocene glacier fluctuations), Barhei- vatnet (bio-proxy lake), Elvejordsvatnet (Holocene glacier fluctuations) and Trollvat- net (early deglaciation, Holocene slope processes) are investigated and bathymetric maps produced. Based
A record of Holocene snow-avalanche activity has been reconstructed from the presence of coarse (... more A record of Holocene snow-avalanche activity has been reconstructed from the presence of coarse (>1 mm) minerogenic particles in lake sediment cores retrieved from Vanndalsvatnet in western Norway. At this site, snow avalanches bring minerogenic debris and macroscopic plant remains from the adjacent valley side south of the lake onto the lake ice. When the lake ice melts during late
Magnetic properties of sediments retrieved from a small lake in northern Norway spanning the last... more Magnetic properties of sediments retrieved from a small lake in northern Norway spanning the last ∼14500 cal. years have been analyzed in detail. The high-resolution core, with its ability to detect sub-centurial variability, records the rapid retreat of the Fennoscandian Ice Sheet (FIS) in northern Lyngen, and subsequently, the establishment of a stable Allerød to Younger Dryas watershed. From early
Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna ... more Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna Peninsula in Hardanger, western Norway. By combining the position of marginal moraines with AMS radiocarbon dated glacier-meltwater induced sediments in proglacial lakes draining northern Folgefonna, a continuous high-resolution record of variations in glacier size and equilibrium-line altitudes (ELAs) during the Lateglacial and early Holocene
During the Lateglacial and early Holocene, abrupt, millennial-scale climatic variations are recor... more During the Lateglacial and early Holocene, abrupt, millennial-scale climatic variations are recorded in a wide range of high-resolution proxy records from marine and terrestrial archives in NW Europe. Our review of the evidence for these rapid climate events do not show an apparent link to possible forcing factors such as long-term, orbitally induced variations in solar radiation, short-term variations in
Based on an exponential relationship between winter precipitation as snow and summer temperature ... more Based on an exponential relationship between winter precipitation as snow and summer temperature at the equilibrium-line altitude (ELA) on modern Norwegian glaciers, it is possible to reconstruct former variations in winter precipitation by combining reconstructed ELAs with independent proxies for summer temperature. Glaciers respond mainly to changes in summer temperature and winter precipitation. By using the exponential relationship between summer
Variations in the North Atlantic Oscillation (NAO) index are reflected in glacier mass balance re... more Variations in the North Atlantic Oscillation (NAO) index are reflected in glacier mass balance records in western Scandinavia. The NAO index is best correlated with the net mass balance on maritime glaciers in southern Norway. Holocene glacier variations of maritime glaciers in western Scandinavia may therefore reflect winter precipitation changes and thus be a proxy for winter climate variability in
Variations in the magnetic signal (MS, SIRM, ARM, S-0.3T) in a high-resolution lacustrine record ... more Variations in the magnetic signal (MS, SIRM, ARM, S-0.3T) in a high-resolution lacustrine record from a small lake in northern Norway (Lyngen) spanning the last 14.500 years have been examined in detail. Our main objective has been (1) to discriminate and identify different sediment phase-changes recorded in this lake archive, and (2) to compare these changes with a broader climatic
The climate gradients over southern Norway are some of the strongest in the world. Generally, the... more The climate gradients over southern Norway are some of the strongest in the world. Generally, the climate change from a strong, maritime climate regime in western Norway to a continental climate regime east of the main watershed less than 150 km from the coast. Four glacier reconstructions have been obtained along this climatic gradient using proglacial terrestrial and lacustrine sites. Modern meteorological data show that the winter climate in western Norway is strongly modulated by changes in the pressure-field over the North-Atlantic. This is best expressed by variations in winter precipitation, where the North Atlantic Oscillation (NAO) index can explain more than 50% of the total precipitation variability. By using a well-established relationship between the summer temperature and winter precipitation at the equilibrium-line altitude of Norwegian glaciers and using independent records of summer temperature fluctuations, the ELA-variations and inferred winter precipitation across the west-to-east transect have been investigated. The regional analyses show that increased precipitation on the west coast also can be detected at the continental glaciers, however, with less amplutude. This shows that the precipitation changes detected on the maritime glaciers are mainly controlled by changes in the atmospheric circulation over the North Atlantic region. It is concluded that low-frequency changes in the strength of North Atlantic winter circulation have occurred during the Holocene.
We study the fracture roughness exponent zeta in (1) the two-dimensional fuse model with disorder... more We study the fracture roughness exponent zeta in (1) the two-dimensional fuse model with disorder in the burn-out thresholds, (2) the fuse model with disorder in the conductances, (3) the fuse model with breaking probability proportional to the current the bonds carry to a power eta. In addition, we have measured the correlation length exponent of the three-dimensional fuse model
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Papers by Jostein Bakke