Morainic loops and trimlines at the outlets of four glacier catchments in the upper part of Schuchertdal, as defined on modern satellite imagery. The lost spectacular loop is related to the LIA (Little Ice Age) surge of the Roslin Gletscher, which culminated in an ice edge on the eastern edge of Schuchertdal.
Surging behaviour is now recognized on many of the small glaciers (ie less than 40 km long) in the uplands of East Greenland. Those of the Werner Mountains and the Staunings Alps are better documented than those of more remote areas, and Roslin Gletscher and Björnbogletscher are mentioned in a number of research publications such as this one:
https://www.researchgate.net/publication/312395822_The_most_extensive_Holocene_advance_in_the_Stauning_Alper_East_Greenland_occurred_in_the_Little_Ice_Age/figures?lo=1
See also:
https://pubs.usgs.gov/pp/p1386c/p1386c.pdf
See also:
https://brian-mountainman.blogspot.com/2010/09/ivar-bardarsons-glacier-then-and-now.html
The last surge (or advance) of the Björnbo Gletscher was contained within its upland trough, but that of the Roslin Gletscher (once called Ivaar Bardarssons Gletscher) involved the creation of a spectacular morainic loop which effectively blocked the Schuchert Valley -- and this has attracted attention since the early days of map making and mineral exploration in the 1950's.
I am quite intrigued by the Ernst Hofer oblique photograph, because it shows a steep ice front and an extremely rough and crevassed ice surface. This suggests to me that the photo was taken shortly after the culmination of a new surge that might have occurred around 1950. When we walked across this glacier in 1962 the ice edge was more or less in the same place, but the glacier surface presented us with no difficulties at all, and we did not even need to rope up. So I think we might have signs here of two (or maybe several) surges, of more or less equal extent.
Were these surges matched in time by the surges in the adjacent glaciers?
The Storgletscher advance, also involving ice from Gannochy Gletscher, also pushed across to the eastern edge of the Schuchert Valley -- but there was also an input from a smaller unnamed glacier to the south. The extent of the ice-cored moraine (with abundant small meltwater lakes) is very clear on the satellite image.
The timing and nature of these surges will no doubt be the subjects of future investigations. But how do they relate to the surging glaciers of NW Iceland? In the area which Dave Sugden and I studied in 1960, and which I revisited with the Vestfirdir Project in 1973-76, the surging behaviour of the Drangajokull outlet glaciers (particularly Kaldalonsjokull, Reykjarfjardarsjokull and Leirufjardarsjokull) is now well documented, with the most marked advances of the ice edges dated to c 1740, 1850 and 1994. In NW Iceland there does not seem to have been a big readvance or surge around 1950.
https://brian-mountainman.blogspot.com/2022/10/the-end-of-kaldalonsjokull.html
https://brian-mountainman.blogspot.com/2019/02/drangajokull-and-kaldalon-nw-iceland.html
As for the other glaciers in NE Greenland, we do know that some of the Nordvestfjord glaciers including Oxford Gletscher and Løberen are liable to surging behaviour, and that the latter (the "galloping glacier" started a massive surge in 1950 and which continued until about 1965.
https://brian-mountainman.blogspot.com/2021/10/oxford-gletscher-surface-thermal-regime.html
https://brian-mountainman.blogspot.com/2013/08/and-now-for-galloping-glacier.html
https://brian-mountainman.blogspot.com/2024/02/lberen-greenlands-galloping-glacier.html
So I have a little theory that there might have been a regional "surge event" in the Staunings Alps area in the period 1950-1960 which affected many of the smaller glaciers which originated in the uplands, and that this event was just slightly less dramatic and less extensive than some of the other surges associated with the Little Ice Age in Greenland and Iceland.
===================
To set this in context:
Glacier response to the Little Ice Age during the Neoglacial cooling in Greenland
Kurt H. Kjær et al, 2022.
Earth-Science Reviews
Volume 227, April 2022, 103984
https://www.sciencedirect.com/science/article/pii/S001282522200068X
Abstract
In the Northern Hemisphere, an insolation driven Early to Middle Holocene Thermal Maximum was followed by a Neoglacial cooling that culminated during the Little Ice Age(LIA). Here, we review the glacier response to this Neoglacial cooling in Greenland. Changes in the ice margins of outlet glaciers from the Greenland Ice Sheet as well as local glaciers and ice caps are synthesized Greenland-wide. In addition, we compare temperature reconstructions from ice cores, elevation changes of the ice sheet across Greenland and oceanographic reconstructions from marine sediment cores over the past 5,000 years. The data are derived from a comprehensive review of the literature supplemented with unpublished reports. Our review provides a synthesis of the sensitivity of the Greenland ice margins and their variability, which is critical to understanding how Neoglacial glacier activity was interrupted by the current anthropogenic warming. We have reconstructed three distinct periods of glacier expansion from our compilation: two older Neoglacial advances at 2,500 – 1,700 yrs. BP (Before Present = 1950 CE, Common Era) and 1,250 – 950 yrs. BP; followed by a general advance during the younger Neoglacial between 700-50 yrs. BP, which represents the LIA. There is still insufficient data to outline the detailed spatio-temporal relationships between these periods of glacier expansion. Many glaciers advanced early in the Neoglacial and persisted in close proximity to their present-day position until the end of the LIA. Thus, the LIA response to Northern Hemisphere cooling must be seen within the wider context of the entire Neoglacial period of the past 5,000 years. Ice expansion appears to be closely linked to changes in ice sheet elevation, accumulation, and temperature as well as surface-water cooling in the surrounding oceans. At least for the two youngest Neoglacial advances, volcanic forcing triggering a sea-ice /ocean feedback, could explain their initiation. There are probably several LIA glacier fluctuations since the first culmination close to 1250 CE (Common Era) and available data suggests ice culminations in the 1400s, early to mid-1700s and early to mid-1800s CE. The last LIA maxima lasted until the present deglaciation commenced around 50 yrs. BP (1900 CE). The constraints provided here on the timing and magnitude of LIA glacier fluctuations delivers a more realistic background validation for modelling future ice sheet stability.
and this:
https://www.sciencedirect.com/science/article/abs/pii/S0277379108001765
Meredith A. Kelly et al, 2008
A 10Be chronology of lateglacial and Holocene mountain glaciation in the Scoresby Sund region, east Greenland: implications for seasonality during lateglacial time.
Quaternary Science Reviews
Volume 27, Issues 25–26, December 2008, Pages 2273-2282
Abstract
Thirty-eight new cosmogenic (10Be) exposure ages from the Scoresby Sund region of east Greenland indicate that prominent moraine sets deposited by mountain glaciers date from 780 to 310 yr, approximately during the Little Ice Age, from 11 660 to 10 630 yr, at the end of the Younger Dryas cold interval or during Preboreal time, and from 13 010 to 11 630 yr, during lateglacial time. Equilibrium line altitudes (ELAs) interpreted from lateglacial to Early Holocene moraines indicate summertime cooling between ∼3.9 and 6.6 °C relative to today's value, much less than the extreme Younger Dryas cooling registered by Greenland ice cores (mean-annual temperatures of ∼15 °C colder than today's value). This apparent discrepancy between paleotemperature records supports the contention that Younger Dryas cooling was primarily a wintertime phenomenon. 10Be ages of lateglacial and Holocene moraines show that mountain glaciers during the Little Ice Age were more extensive than at any other time since the Early Holocene Epoch. In addition, 10Be ages of lateglacial moraines show extensive reworking of boulders with cosmogenic nuclides inherited from prior periods of exposure, consistent with our geomorphic observations and cosmogenic-exposure dating studies in other Arctic regions.
.......... and this:
https://www.researchgate.net/publication/312395822_The_most_extensive_Holocene_advance_in_the_Stauning_Alper_East_Greenland_occurred_in_the_Little_Ice_Age
The most extensive Holocene advance in the Stauning Alper, East Greenland, occurred in the Little Ice Age
Funder S. 1970. Notes on the glacial geology of eastern Milne Land. Rapport Grønlands Geologiske Undersøgelse 30, 37-42
https://www.researchgate.net/publication/312395822_The_most_extensive_Holocene_advance_in_the_Stauning_Alper_East_Greenland_occurred_in_the_Little_Ice_Age/figures?lo=1
See also:
https://pubs.usgs.gov/pp/p1386c/p1386c.pdf
See also:
https://brian-mountainman.blogspot.com/2010/09/ivar-bardarsons-glacier-then-and-now.html
The last surge (or advance) of the Björnbo Gletscher was contained within its upland trough, but that of the Roslin Gletscher (once called Ivaar Bardarssons Gletscher) involved the creation of a spectacular morainic loop which effectively blocked the Schuchert Valley -- and this has attracted attention since the early days of map making and mineral exploration in the 1950's.
Roslin Gletscher ice front in 1954 -- photo by Ernst Hofer. He described the ice front as being 30m high at the time.
The maximum extent of the Little Ice Age surge morainic loop. The 1954 ice edge is also demarcated. This is possible because some of the landforms -- such as the large lake -- can be identified on all existing aerial photos.
I am quite intrigued by the Ernst Hofer oblique photograph, because it shows a steep ice front and an extremely rough and crevassed ice surface. This suggests to me that the photo was taken shortly after the culmination of a new surge that might have occurred around 1950. When we walked across this glacier in 1962 the ice edge was more or less in the same place, but the glacier surface presented us with no difficulties at all, and we did not even need to rope up. So I think we might have signs here of two (or maybe several) surges, of more or less equal extent.
Were these surges matched in time by the surges in the adjacent glaciers?
At the top of the photo we can see the maximum extent of the ice lobe at the head of the Schuchert Valley -- carrying ice from several linked glaciers -- namely Schuchert Gletscher itself, Arcturus Gletscher, Sirius Gletscher, Aldebaran Gletscher and a number of smaller tributary glaciers in the Werner Mountains. The ice edge has since retreated by about 4 km.
The Storgletscher advance, also involving ice from Gannochy Gletscher, also pushed across to the eastern edge of the Schuchert Valley -- but there was also an input from a smaller unnamed glacier to the south. The extent of the ice-cored moraine (with abundant small meltwater lakes) is very clear on the satellite image.
The timing and nature of these surges will no doubt be the subjects of future investigations. But how do they relate to the surging glaciers of NW Iceland? In the area which Dave Sugden and I studied in 1960, and which I revisited with the Vestfirdir Project in 1973-76, the surging behaviour of the Drangajokull outlet glaciers (particularly Kaldalonsjokull, Reykjarfjardarsjokull and Leirufjardarsjokull) is now well documented, with the most marked advances of the ice edges dated to c 1740, 1850 and 1994. In NW Iceland there does not seem to have been a big readvance or surge around 1950.
https://brian-mountainman.blogspot.com/2022/10/the-end-of-kaldalonsjokull.html
https://brian-mountainman.blogspot.com/2019/02/drangajokull-and-kaldalon-nw-iceland.html
As for the other glaciers in NE Greenland, we do know that some of the Nordvestfjord glaciers including Oxford Gletscher and Løberen are liable to surging behaviour, and that the latter (the "galloping glacier" started a massive surge in 1950 and which continued until about 1965.
https://brian-mountainman.blogspot.com/2021/10/oxford-gletscher-surface-thermal-regime.html
https://brian-mountainman.blogspot.com/2013/08/and-now-for-galloping-glacier.html
https://brian-mountainman.blogspot.com/2024/02/lberen-greenlands-galloping-glacier.html
So I have a little theory that there might have been a regional "surge event" in the Staunings Alps area in the period 1950-1960 which affected many of the smaller glaciers which originated in the uplands, and that this event was just slightly less dramatic and less extensive than some of the other surges associated with the Little Ice Age in Greenland and Iceland.
===================
To set this in context:
Glacier response to the Little Ice Age during the Neoglacial cooling in Greenland
Kurt H. Kjær et al, 2022.
Earth-Science Reviews
Volume 227, April 2022, 103984
https://www.sciencedirect.com/science/article/pii/S001282522200068X
Abstract
In the Northern Hemisphere, an insolation driven Early to Middle Holocene Thermal Maximum was followed by a Neoglacial cooling that culminated during the Little Ice Age(LIA). Here, we review the glacier response to this Neoglacial cooling in Greenland. Changes in the ice margins of outlet glaciers from the Greenland Ice Sheet as well as local glaciers and ice caps are synthesized Greenland-wide. In addition, we compare temperature reconstructions from ice cores, elevation changes of the ice sheet across Greenland and oceanographic reconstructions from marine sediment cores over the past 5,000 years. The data are derived from a comprehensive review of the literature supplemented with unpublished reports. Our review provides a synthesis of the sensitivity of the Greenland ice margins and their variability, which is critical to understanding how Neoglacial glacier activity was interrupted by the current anthropogenic warming. We have reconstructed three distinct periods of glacier expansion from our compilation: two older Neoglacial advances at 2,500 – 1,700 yrs. BP (Before Present = 1950 CE, Common Era) and 1,250 – 950 yrs. BP; followed by a general advance during the younger Neoglacial between 700-50 yrs. BP, which represents the LIA. There is still insufficient data to outline the detailed spatio-temporal relationships between these periods of glacier expansion. Many glaciers advanced early in the Neoglacial and persisted in close proximity to their present-day position until the end of the LIA. Thus, the LIA response to Northern Hemisphere cooling must be seen within the wider context of the entire Neoglacial period of the past 5,000 years. Ice expansion appears to be closely linked to changes in ice sheet elevation, accumulation, and temperature as well as surface-water cooling in the surrounding oceans. At least for the two youngest Neoglacial advances, volcanic forcing triggering a sea-ice /ocean feedback, could explain their initiation. There are probably several LIA glacier fluctuations since the first culmination close to 1250 CE (Common Era) and available data suggests ice culminations in the 1400s, early to mid-1700s and early to mid-1800s CE. The last LIA maxima lasted until the present deglaciation commenced around 50 yrs. BP (1900 CE). The constraints provided here on the timing and magnitude of LIA glacier fluctuations delivers a more realistic background validation for modelling future ice sheet stability.
and this:
https://www.sciencedirect.com/science/article/abs/pii/S0277379108001765
Meredith A. Kelly et al, 2008
A 10Be chronology of lateglacial and Holocene mountain glaciation in the Scoresby Sund region, east Greenland: implications for seasonality during lateglacial time.
Quaternary Science Reviews
Volume 27, Issues 25–26, December 2008, Pages 2273-2282
Abstract
Thirty-eight new cosmogenic (10Be) exposure ages from the Scoresby Sund region of east Greenland indicate that prominent moraine sets deposited by mountain glaciers date from 780 to 310 yr, approximately during the Little Ice Age, from 11 660 to 10 630 yr, at the end of the Younger Dryas cold interval or during Preboreal time, and from 13 010 to 11 630 yr, during lateglacial time. Equilibrium line altitudes (ELAs) interpreted from lateglacial to Early Holocene moraines indicate summertime cooling between ∼3.9 and 6.6 °C relative to today's value, much less than the extreme Younger Dryas cooling registered by Greenland ice cores (mean-annual temperatures of ∼15 °C colder than today's value). This apparent discrepancy between paleotemperature records supports the contention that Younger Dryas cooling was primarily a wintertime phenomenon. 10Be ages of lateglacial and Holocene moraines show that mountain glaciers during the Little Ice Age were more extensive than at any other time since the Early Holocene Epoch. In addition, 10Be ages of lateglacial moraines show extensive reworking of boulders with cosmogenic nuclides inherited from prior periods of exposure, consistent with our geomorphic observations and cosmogenic-exposure dating studies in other Arctic regions.
.......... and this:
https://www.researchgate.net/publication/312395822_The_most_extensive_Holocene_advance_in_the_Stauning_Alper_East_Greenland_occurred_in_the_Little_Ice_Age
The most extensive Holocene advance in the Stauning Alper, East Greenland, occurred in the Little Ice Age
Brenda L. Hall, Carlo Baroni & George H. Denton
Polar Research 27(2)
DOI: 10.3402/polar.v27i2.6171
Abstract
The paper by Hall, Baroni and Denton confirms what David Sugden and myself proposed in 1965: namely that by around 11,000 yrs BP most glacier ice has melted away in Schuchertdal, allowing a substantial marine incursion of the valley -- at least as far up-valley as the side trough of the Roslin Gletscher. This allowed the creation of marine terraces at and below 67 m asl. This may have coincided with the formation of the major marine delta terrace at c 67m in the "Gurreholm Staircase" as measured by David and me in 1962. Radiocarbon dating of marine mollusca contained within these terrace remnants suggests ice-free conditions at around 10,700 yrs BP. The presence of marine terrace fragments all the way down the valley confirms that there was no substantial Neoglacial ice advance until the Little Ice Age -- at which time the spectacular loops of moraine at the glacier fronts were created.
Polar Research 27(2)
DOI: 10.3402/polar.v27i2.6171
Abstract
We present glacial geologic and chronologic data concerning the Holocene ice extent in the Stauning Alper of East Greenland. The retreat of ice from the late-glacial position back into the mountains was accomplished by at least11 000 cal years B.P. The only recorded advance after this time occurred duringthe past few centuries (the Little Ice Age). Therefore, we postulate that the Little Ice Age event represents the maximum Holocene ice extent in this part of East Greenland.
================
The paper by Hall, Baroni and Denton confirms what David Sugden and myself proposed in 1965: namely that by around 11,000 yrs BP most glacier ice has melted away in Schuchertdal, allowing a substantial marine incursion of the valley -- at least as far up-valley as the side trough of the Roslin Gletscher. This allowed the creation of marine terraces at and below 67 m asl. This may have coincided with the formation of the major marine delta terrace at c 67m in the "Gurreholm Staircase" as measured by David and me in 1962. Radiocarbon dating of marine mollusca contained within these terrace remnants suggests ice-free conditions at around 10,700 yrs BP. The presence of marine terrace fragments all the way down the valley confirms that there was no substantial Neoglacial ice advance until the Little Ice Age -- at which time the spectacular loops of moraine at the glacier fronts were created.
https://geusjournals.org/index.php/rapggu/article/view/7243/13113
Funder S. 1970. Notes on the glacial geology of eastern Milne
Land.
Rapport Grønlands Geologiske Undersøgelse 30
,37
42
Funder S. 1970. Notes on the glacial geology of eastern Milne
Land.
Rapport Grønlands Geologiske Undersøgelse 30
,37
42
Funder S. 1970. Notes on the glacial geology of eastern Milne
Land.
Rapport Grønlands Geologiske Undersøgelse 30
,37
42
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