Liss M. Andreassen, Benjamin A. Robson, Kamilla H. Sjursen, Hallgeir Elvehøy, Bjarne Kjøllmoen, Jonathan L. Carrivick
The Jostedalsbreen ice cap is mainland Europe's largest ice cap and accommodates 20% (458 km2 in 2019) of the total glacier area of mainland Norway. Jostedalsbreen and its meltwater contribute to global sea-level rise and to local water management, hydropower and tourism economies and livelihoods. In this study, we construct a digital terrain model (DTM) of the ice cap from 1966 aerial photographs, which by comparing to an airborne LiDAR DTM from 2020, we compute changes in surface elevation and geodetic mass balances. The area mapped in both surveys cover about 3/4 of the ice cap area and 49 of 82 glaciers. The measured glacier area has decreased from 363.4 km2 in 1966 to 332.9 km2 in 2019, i.e. a change of −30 km2 or −8.4% (−0.16% a−1), which is in line with the percentage reduction in area for Jostedalsbreen as a whole. The mean geodetic mass balance over the 49 glaciers was −0.15 ± 0.01 m w.e. a−1, however, large variability is evident between glaciers, e.g. Nigardsbreen (−0.05 m w.e. a−1), Austdalsbreen (−0.28 m w.e. a−1) and Tunsbergdalsbreen (−0.36 m w.e. a−1) confirming differences also found by the glaciological records for Nigardsbreen and Austdalsbreen.
Jostedalsbreen冰帽是欧洲大陆最大的冰帽，占挪威大陆冰川总面积的20%(2019年为458平方公里)。Jostedalsbreen及其融水对全球海平面上升、当地水资源管理、水电、旅游经济和生计做出了贡献。在这项研究中，我们从1966年的航空照片中构建了一个冰盖的数字地形模型(DTM)，通过与2020年的机载激光雷达DTM进行比较，我们计算了地表高程和大地质量平衡的变化。这两项调查绘制的区域覆盖了大约3/4的冰盖面积和82个冰川中的49个。测量的冰川面积从1966年的363.4 km2减少到2019年的332.9 km2，即变化了- 30 km2或- 8.4% (- 0.16% a - 1)，这与Jostedalsbreen整体面积减少的百分比一致。49个冰川的平均大地质量平衡为- 0.15±0.01 m w.e.a−1，但在尼加德斯布林(- 0.05 m w.e.a−1)、奥斯达尔斯布林(- 0.28 m w.e.a−1)和通斯伯格达尔斯布林(- 0.36 m w.e.a−1)冰川之间存在明显的差异，证实了尼加德斯布林和奥斯达尔斯布林冰川记录的差异。
{"title":"Spatio-temporal variability in geometry and geodetic mass balance of Jostedalsbreen ice cap, Norway","authors":"Liss M. Andreassen, Benjamin A. Robson, Kamilla H. Sjursen, Hallgeir Elvehøy, Bjarne Kjøllmoen, Jonathan L. Carrivick","doi":"10.1017/aog.2023.70","DOIUrl":"https://doi.org/10.1017/aog.2023.70","url":null,"abstract":"The Jostedalsbreen ice cap is mainland Europe's largest ice cap and accommodates 20% (458 km<jats:sup>2</jats:sup> in 2019) of the total glacier area of mainland Norway. Jostedalsbreen and its meltwater contribute to global sea-level rise and to local water management, hydropower and tourism economies and livelihoods. In this study, we construct a digital terrain model (DTM) of the ice cap from 1966 aerial photographs, which by comparing to an airborne LiDAR DTM from 2020, we compute changes in surface elevation and geodetic mass balances. The area mapped in both surveys cover about 3/4 of the ice cap area and 49 of 82 glaciers. The measured glacier area has decreased from 363.4 km<jats:sup>2</jats:sup> in 1966 to 332.9 km<jats:sup>2</jats:sup> in 2019, i.e. a change of −30 km<jats:sup>2</jats:sup> or −8.4% (−0.16% a<jats:sup>−1</jats:sup>), which is in line with the percentage reduction in area for Jostedalsbreen as a whole. The mean geodetic mass balance over the 49 glaciers was −0.15 ± 0.01 m w.e. a<jats:sup>−1</jats:sup>, however, large variability is evident between glaciers, e.g. Nigardsbreen (−0.05 m w.e. a<jats:sup>−1</jats:sup>), Austdalsbreen (−0.28 m w.e. a<jats:sup>−1</jats:sup>) and Tunsbergdalsbreen (−0.36 m w.e. a<jats:sup>−1</jats:sup>) confirming differences also found by the glaciological records for Nigardsbreen and Austdalsbreen.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"100 5","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138509561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicole Schaffer, Luke Copland, Christian Zdanowicz, Regine Hock
Abstract Glaciers of Baffin Island and nearby islands of Arctic Canada have experienced rapid mass losses over recent decades. However, projections of loss rates into the 21st century have so far been limited by the availability of model calibration and validation data. In this study, we model the surface mass balance of the largest ice cap on Baffin Island, Penny Ice Cap, since 1959, using an enhanced temperature index model calibrated with in situ data from 2006–2014. Subsequently, we project changes to 2099 based on the RCP4.5 climate scenario. Since the mid-1990s, the surface mass balance over Penny Ice Cap has become increasingly negative, particularly after 2005. Using volume–area scaling to account for glacier retreat, peak net mass loss is projected to occur between ~2040 and 2080, and the ice cap is expected to lose 22% (377.4 Gt or 60 m w.e.) of its 2014 ice mass by 2099, contributing 1.0 mm to sea level rise. Our 2015–2099 projections are approximately nine times more sensitive to changes in temperature than precipitation, with an absolute cumulative difference of 566 Gt a –1 (90 m w.e.) between +2 and −2°C scenarios, and 63 Gt a –1 (10 m w.e.) between +20% and −20% precipitation scenarios.
近几十年来，巴芬岛和加拿大北极附近岛屿的冰川经历了快速的质量损失。然而，到目前为止，对21世纪损失率的预估受到模型校准和验证数据的限制。在这项研究中，我们利用2006-2014年现场数据校准的增强温度指数模型，模拟了巴芬岛最大的冰帽Penny冰帽自1959年以来的表面质量平衡。随后，我们基于RCP4.5气候情景预估到2099年的变化。自20世纪90年代中期以来，彭尼冰帽的表面物质平衡越来越负，特别是在2005年之后。利用体积面积尺度来考虑冰川退缩，预计净质量损失峰值将在~2040年至2080年之间出现，到2099年，冰盖预计将损失2014年冰质量的22% (377.4 Gt或60 m w.e)，导致海平面上升1.0 mm。我们的2015-2099年预估对温度变化的敏感性大约是降水的9倍，在+2°C和- 2°C情景之间的绝对累积差为566 Gt a -1 (90 m w.e)，在+20%和- 20%降水情景之间的绝对累积差为63 Gt a -1 (10 m w.e)。
{"title":"Modeling the surface mass balance of Penny Ice Cap, Baffin Island, 1959–2099","authors":"Nicole Schaffer, Luke Copland, Christian Zdanowicz, Regine Hock","doi":"10.1017/aog.2023.68","DOIUrl":"https://doi.org/10.1017/aog.2023.68","url":null,"abstract":"Abstract Glaciers of Baffin Island and nearby islands of Arctic Canada have experienced rapid mass losses over recent decades. However, projections of loss rates into the 21st century have so far been limited by the availability of model calibration and validation data. In this study, we model the surface mass balance of the largest ice cap on Baffin Island, Penny Ice Cap, since 1959, using an enhanced temperature index model calibrated with in situ data from 2006–2014. Subsequently, we project changes to 2099 based on the RCP4.5 climate scenario. Since the mid-1990s, the surface mass balance over Penny Ice Cap has become increasingly negative, particularly after 2005. Using volume–area scaling to account for glacier retreat, peak net mass loss is projected to occur between ~2040 and 2080, and the ice cap is expected to lose 22% (377.4 Gt or 60 m w.e.) of its 2014 ice mass by 2099, contributing 1.0 mm to sea level rise. Our 2015–2099 projections are approximately nine times more sensitive to changes in temperature than precipitation, with an absolute cumulative difference of 566 Gt a –1 (90 m w.e.) between +2 and −2°C scenarios, and 63 Gt a –1 (10 m w.e.) between +20% and −20% precipitation scenarios.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"119 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135137176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kaian Shahateet, Francisco Navarro, Thorsten Seehaus, Johannes J. Fürst, Matthias Braun
Abstract The Antarctic Peninsula Ice Sheet (APIS) has become a significant contributor to sea-level rise over recent decades. Accurately estimating the ice discharge from the outlet glaciers of the APIS is crucial to quantify the mass balance of the Antarctic Peninsula. We here compute the ice discharge from the outlet glaciers of the APIS north of 70 ${^circ }$ S for the five most widely used ice-thickness reconstructions, using a common surface velocity field and a common set of flux gates, so the differences in ice discharge can be solely attributed to the differences in ice thickness at the flux gates. The total volumetric ice discharge for 2015–2017 ranges within 45–141 km 3 a −1 , depending on the ice-thickness model, with a mean of 87 ± 44 km 3 a −1 . The substantial differences between the ice-discharge results, and a multi-model normalized root-mean-squared deviation of 0.91 for the whole data set, reveal large differences and inconsistencies between the ice-thickness models, giving an indication of the large uncertainty in the current ice-discharge estimates for the APIS. This manifests a fundamental problem of the region: the scarcity of appropriate ice-thickness measurements and the difficulty of the current models to reconstruct the ice-thickness distribution in this complex region.
近几十年来，南极半岛冰盖(APIS)已成为海平面上升的重要贡献者。准确估算南极冰原出口冰川的冰流量对量化南极半岛的物质平衡至关重要。在此，我们使用一个共同的表面速度场和一组共同的通量门，计算了在70 ${^circ}$ S以北的五个最广泛使用的冰厚重建的api出口冰川的冰流量，因此冰流量的差异可以完全归因于通量门处冰厚的差异。根据不同的冰厚模式，2015-2017年的总冰流量在45-141 km 3 a−1之间，平均为87±44 km 3 a−1。冰流量结果之间的巨大差异，以及整个数据集的多模型归一化均方根偏差为0.91，表明冰厚度模型之间存在很大差异和不一致性，表明目前api冰流量估计存在很大的不确定性。这反映了该地区的一个根本问题:缺乏适当的冰厚测量，现有模型难以重建这一复杂地区的冰厚分布。
{"title":"Estimating ice discharge of the Antarctic Peninsula using different ice-thickness datasets","authors":"Kaian Shahateet, Francisco Navarro, Thorsten Seehaus, Johannes J. Fürst, Matthias Braun","doi":"10.1017/aog.2023.67","DOIUrl":"https://doi.org/10.1017/aog.2023.67","url":null,"abstract":"Abstract The Antarctic Peninsula Ice Sheet (APIS) has become a significant contributor to sea-level rise over recent decades. Accurately estimating the ice discharge from the outlet glaciers of the APIS is crucial to quantify the mass balance of the Antarctic Peninsula. We here compute the ice discharge from the outlet glaciers of the APIS north of 70 ${^circ }$ S for the five most widely used ice-thickness reconstructions, using a common surface velocity field and a common set of flux gates, so the differences in ice discharge can be solely attributed to the differences in ice thickness at the flux gates. The total volumetric ice discharge for 2015–2017 ranges within 45–141 km 3 a −1 , depending on the ice-thickness model, with a mean of 87 ± 44 km 3 a −1 . The substantial differences between the ice-discharge results, and a multi-model normalized root-mean-squared deviation of 0.91 for the whole data set, reveal large differences and inconsistencies between the ice-thickness models, giving an indication of the large uncertainty in the current ice-discharge estimates for the APIS. This manifests a fundamental problem of the region: the scarcity of appropriate ice-thickness measurements and the difficulty of the current models to reconstruct the ice-thickness distribution in this complex region.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"9 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135479713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicolás González-Santacruz, Patricia Muñoz-Marzagon, Miguel Bartolomé, Ana Moreno, Jennifer Huidobro, Sérgio Henrique Faria
Abstract Monte Perdido Glacier, located in the central Pyrenees, is one of the southernmost glaciers in Europe. Due to climate change, this glacier is suffering an accelerated mass loss, especially in the last decades. If the current trends persist, this glacier is expected to disappear in the next 50 years. As part of the efforts of the scientific community to increase the knowledge about this glacier, this research presents the first microstructural characterization of the Monte Perdido Glacier, focused on a high-impurity concentration segment that belongs to an ice core drilled in 2017. The results reveal the ice has a layering defined by air bubbles and non-soluble impurities. The bubble-defined layering exhibits features of both a primary (sedimentary) and a secondary (strain-induced) origin. We found a clear inverse correspondence between the particle concentration and the grains' size and roundness index. A preliminary micro-Raman characterization of the particles shows the occurrence of atacamite, anatase (likely related to ancient mining activities in the vicinity of the glacier) and quartz. The latter could be an indicator of mineral dust, probably suggesting the arrival of dust-laden air masses from the north of the African continent.
Monte Perdido冰川位于比利牛斯山脉中部，是欧洲最南端的冰川之一。由于气候变化，这条冰川正在遭受加速的质量损失，特别是在过去的几十年里。如果目前的趋势持续下去，预计这座冰川将在未来50年内消失。作为科学界增加对该冰川知识的努力的一部分，本研究首次对Monte Perdido冰川进行了微观结构表征，重点研究了2017年钻探的冰芯中高杂质浓度的部分。结果表明，冰具有由气泡和不溶性杂质定义的分层。气泡定义的层理具有原生(沉积)和次生(应变)成因的特征。我们发现颗粒浓度与晶粒尺寸和圆度指数呈明显的反比关系。对这些颗粒进行的初步微观拉曼表征显示，它们含有无辉石、锐钛矿(可能与冰川附近的古代采矿活动有关)和石英。后者可能是矿物尘埃的一个指标，可能表明来自非洲大陆北部的含尘气团的到来。
{"title":"Effects of impurities on the ice microstructure of Monte Perdido Glacier, Central Pyrenees, NE Spain","authors":"Nicolás González-Santacruz, Patricia Muñoz-Marzagon, Miguel Bartolomé, Ana Moreno, Jennifer Huidobro, Sérgio Henrique Faria","doi":"10.1017/aog.2023.66","DOIUrl":"https://doi.org/10.1017/aog.2023.66","url":null,"abstract":"Abstract Monte Perdido Glacier, located in the central Pyrenees, is one of the southernmost glaciers in Europe. Due to climate change, this glacier is suffering an accelerated mass loss, especially in the last decades. If the current trends persist, this glacier is expected to disappear in the next 50 years. As part of the efforts of the scientific community to increase the knowledge about this glacier, this research presents the first microstructural characterization of the Monte Perdido Glacier, focused on a high-impurity concentration segment that belongs to an ice core drilled in 2017. The results reveal the ice has a layering defined by air bubbles and non-soluble impurities. The bubble-defined layering exhibits features of both a primary (sedimentary) and a secondary (strain-induced) origin. We found a clear inverse correspondence between the particle concentration and the grains' size and roundness index. A preliminary micro-Raman characterization of the particles shows the occurrence of atacamite, anatase (likely related to ancient mining activities in the vicinity of the glacier) and quartz. The latter could be an indicator of mineral dust, probably suggesting the arrival of dust-laden air masses from the north of the African continent.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"7 2‐3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135821503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lander Van Tricht, Chloë Marie Paice, Oleg Rybak, Victor Popovnin, Rysbek Satylkanov, Philippe Huybrechts
Abstract The geodetic mass balance of a glacier corresponds to glacier-wide volume changes, converted to mass changes using density assumptions. It is typically calculated by differencing multi-temporal digital elevation models. In this study, we show how the annual geodetic mass balance of a glacier can be derived from uncrewed aerial vehicle (UAV) data. The presented workflow is applied to two small- to medium-sized glaciers in the Kyrgyz Tien Shan (Central Asia): Bordu glacier and Sary-Tor glacier. The obtained geodetic mass balance is compared with the glaciological mass balance derived from a network of ablation stakes and snow pits. A previously calibrated mass-balance model is used to correct for the difference in acquisition dates. The results show that the determined geodetic mass balance matches closely with the glaciological mass balance. Besides, for both glaciers the geodetic mass balance does not seem to be particularly sensitive to the assumptions regarding volume-to-mass conversion. Therefore, our results demonstrate that UAVs can serve as a valuable instrument to quantify the annual geodetic mass balance and to validate the glaciological mass balance. The conventional glaciological mass-balance estimation often relies on interpolation and extrapolation methods, whereas UAVs offer the potential for direct data acquisition over the entire glacier surface.
{"title":"Monitoring the annual geodetic mass balance of Bordu and Sary-Tor glaciers using UAV data","authors":"Lander Van Tricht, Chloë Marie Paice, Oleg Rybak, Victor Popovnin, Rysbek Satylkanov, Philippe Huybrechts","doi":"10.1017/aog.2023.71","DOIUrl":"https://doi.org/10.1017/aog.2023.71","url":null,"abstract":"Abstract The geodetic mass balance of a glacier corresponds to glacier-wide volume changes, converted to mass changes using density assumptions. It is typically calculated by differencing multi-temporal digital elevation models. In this study, we show how the annual geodetic mass balance of a glacier can be derived from uncrewed aerial vehicle (UAV) data. The presented workflow is applied to two small- to medium-sized glaciers in the Kyrgyz Tien Shan (Central Asia): Bordu glacier and Sary-Tor glacier. The obtained geodetic mass balance is compared with the glaciological mass balance derived from a network of ablation stakes and snow pits. A previously calibrated mass-balance model is used to correct for the difference in acquisition dates. The results show that the determined geodetic mass balance matches closely with the glaciological mass balance. Besides, for both glaciers the geodetic mass balance does not seem to be particularly sensitive to the assumptions regarding volume-to-mass conversion. Therefore, our results demonstrate that UAVs can serve as a valuable instrument to quantify the annual geodetic mass balance and to validate the glaciological mass balance. The conventional glaciological mass-balance estimation often relies on interpolation and extrapolation methods, whereas UAVs offer the potential for direct data acquisition over the entire glacier surface.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"6 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135821506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Lombardo, Peter Lehmann, Anders Kaestner, Amelie Fees, Alec Van Herwijnen, Jürg Schweizer
Abstract Liquid water at the ground–snow interface is thought to play a crucial role in the release of glide-snow avalanches, which can be massive and threaten infrastructure in alpine regions. Several mechanisms have been postulated to explain the formation of this interfacial water. However, these mechanisms remain poorly understood, in part because suitable measurement techniques are lacking. Here, we demonstrate the use of neutron radiography for imaging water transport in soil–snow systems. Columns of sand, gravel and snow were used to simulate the capillary forces of the soil–vegetation–snow layering found in nature. The columns were connected to a water reservoir to maintain a constant-pressure boundary condition and placed in a climatic chamber within the neutron beam. We show that neutron radiography is capable of measuring changes in the optical density distribution (related to liquid water content) within all three layers of the model system. Results suggest that a porous interface between the sand and snow may induce the formation of a water layer in the basal snowpack. Improved understanding of the water transport in soil–snow systems should lead to better prediction of glide-snow avalanche release and could also benefit other fields such as snow hydrology.
{"title":"A method for imaging water transport in soil–snow systems with neutron radiography","authors":"Michael Lombardo, Peter Lehmann, Anders Kaestner, Amelie Fees, Alec Van Herwijnen, Jürg Schweizer","doi":"10.1017/aog.2023.65","DOIUrl":"https://doi.org/10.1017/aog.2023.65","url":null,"abstract":"Abstract Liquid water at the ground–snow interface is thought to play a crucial role in the release of glide-snow avalanches, which can be massive and threaten infrastructure in alpine regions. Several mechanisms have been postulated to explain the formation of this interfacial water. However, these mechanisms remain poorly understood, in part because suitable measurement techniques are lacking. Here, we demonstrate the use of neutron radiography for imaging water transport in soil–snow systems. Columns of sand, gravel and snow were used to simulate the capillary forces of the soil–vegetation–snow layering found in nature. The columns were connected to a water reservoir to maintain a constant-pressure boundary condition and placed in a climatic chamber within the neutron beam. We show that neutron radiography is capable of measuring changes in the optical density distribution (related to liquid water content) within all three layers of the model system. Results suggest that a porous interface between the sand and snow may induce the formation of a water layer in the basal snowpack. Improved understanding of the water transport in soil–snow systems should lead to better prediction of glide-snow avalanche release and could also benefit other fields such as snow hydrology.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135872384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Neuhauser, Anselm Köhler, Rene Neurauter, Marc S. Adams, Jan-Thomas Fischer
Abstract Understanding the dynamics of snow avalanches is crucial for predicting their destructive potential and mobility. To gain insight into avalanche dynamics at a particle level, the AvaNode in-flow sensor system was developed. These synthetic particles, equipped with advanced and affordable sensors such as an inertial measurement unit (IMU) and global navigation satellite system (GNSS), travel with the avalanche flow. This study focuses on assessing the feasibility of the in-flow measurement systems. The experiments were conducted during the winter seasons of 2021–2023, both in static snow cover and dynamic avalanche conditions of medium-sized events. Radar measurements were used in conjunction with the particle trajectories and velocities to understand the behaviour of the entire avalanche flow. The dynamic avalanche experiments allowed to identify three distinct particle flow states: (I) initial rapid acceleration, (II) a steady state flow with the highest velocities (9–17 ms −1 ), and (III) a longer deceleration state accompanied by the largest measured rotation rates. The particles tend to travel towards the tail of the avalanche and reach lower velocities compared to the frontal approach velocities deduced from radar measurements (ranging between 23–28 ms −1 ). The presented data give a first insight in avalanche particle measurements.
{"title":"Particle trajectories, velocities, accelerations and rotation rates in snow avalanches","authors":"Michael Neuhauser, Anselm Köhler, Rene Neurauter, Marc S. Adams, Jan-Thomas Fischer","doi":"10.1017/aog.2023.69","DOIUrl":"https://doi.org/10.1017/aog.2023.69","url":null,"abstract":"Abstract Understanding the dynamics of snow avalanches is crucial for predicting their destructive potential and mobility. To gain insight into avalanche dynamics at a particle level, the AvaNode in-flow sensor system was developed. These synthetic particles, equipped with advanced and affordable sensors such as an inertial measurement unit (IMU) and global navigation satellite system (GNSS), travel with the avalanche flow. This study focuses on assessing the feasibility of the in-flow measurement systems. The experiments were conducted during the winter seasons of 2021–2023, both in static snow cover and dynamic avalanche conditions of medium-sized events. Radar measurements were used in conjunction with the particle trajectories and velocities to understand the behaviour of the entire avalanche flow. The dynamic avalanche experiments allowed to identify three distinct particle flow states: (I) initial rapid acceleration, (II) a steady state flow with the highest velocities (9–17 ms −1 ), and (III) a longer deceleration state accompanied by the largest measured rotation rates. The particles tend to travel towards the tail of the avalanche and reach lower velocities compared to the frontal approach velocities deduced from radar measurements (ranging between 23–28 ms −1 ). The presented data give a first insight in avalanche particle measurements.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"25 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135863032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria-Jose Iriarte-Chiapusso, Miren Ayerdi, Naroa Garcia-Ibaibarriaga, Arantzazu J. Pérez-Fernández, Aritza Villaluenga, Jon Arrizabalaga-Iriarte, Lide Lejonagoitia-Garmendia, Alvaro Arrizabalaga
Abstract Upper Palaeolithic archaeological sites in the Basque Country have been excavated for over a century. They have yielded a rich palaeoenvironmental record with zoological and botanical remains that have been obtained in stratigraphic series dated precisely by radiocarbon. This information reveals cyclical environmental changes from climates similar to today to drier and extremely cold conditions, when species in current boreal biomes and others now extinct but with similar ecological preferences were present in the region. Moreover, the archaeological sites have provided high-resolution information about the resilience mechanisms of the communities of our own human species. This information allows us to increase the corpus of palaeoclimate data regarding the Marine Isotopic Stage (MIS) 2 and MIS 3 for a critical region within the human population of Eurasia. The aim of this paper is to show how an extraordinary capacity for adaptation to drastic climate changes Upper Palaeolithic hunter–gatherer societies displayed, even though their subsistence depended on biotic resources that alter rapidly.
{"title":"Upper Palaeolithic hunter–gatherer societies in the Basque Country (Iberian Peninsula) in the light of palaeoenvironmental dynamics in the last Glacial Period: cultural adaptations and the use of biotic resources","authors":"Maria-Jose Iriarte-Chiapusso, Miren Ayerdi, Naroa Garcia-Ibaibarriaga, Arantzazu J. Pérez-Fernández, Aritza Villaluenga, Jon Arrizabalaga-Iriarte, Lide Lejonagoitia-Garmendia, Alvaro Arrizabalaga","doi":"10.1017/aog.2023.60","DOIUrl":"https://doi.org/10.1017/aog.2023.60","url":null,"abstract":"Abstract Upper Palaeolithic archaeological sites in the Basque Country have been excavated for over a century. They have yielded a rich palaeoenvironmental record with zoological and botanical remains that have been obtained in stratigraphic series dated precisely by radiocarbon. This information reveals cyclical environmental changes from climates similar to today to drier and extremely cold conditions, when species in current boreal biomes and others now extinct but with similar ecological preferences were present in the region. Moreover, the archaeological sites have provided high-resolution information about the resilience mechanisms of the communities of our own human species. This information allows us to increase the corpus of palaeoclimate data regarding the Marine Isotopic Stage (MIS) 2 and MIS 3 for a critical region within the human population of Eurasia. The aim of this paper is to show how an extraordinary capacity for adaptation to drastic climate changes Upper Palaeolithic hunter–gatherer societies displayed, even though their subsistence depended on biotic resources that alter rapidly.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"159 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136262758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The spatiotemporal distribution of snow affects hydrological and climatological processes at different scales. Accordingly, quantifying geometric features of snow-cover patterns is important, providing a valuable complement for snow water equivalent (SWE) modelling. This study on satellite-based morphological analysis originally uses two types of geometric indexes: (1) MN, Minkowski numbers (area (MN1), perimeter (MN2), Euler number (MN3)), and (2) CL, average chord length, to describe the morphology of Sentinel-2-derived snow-covered areas (SCAs), within the high-alpine site Zugspitze for a 5 year period. Results indicate that they capture the seasonal variability of snow-cover patterns, particularly during accumulation and ablation. Being to some degree independent from each other, MN2, MN3 and CL provide additional information upon shape, connectivity and length scale of snow cover, compared to most used indexes (e.g. fractional SCA). Correlation values up to +0.7 for MN2, +0.58 for MN3 and +0.46 for CL were observed with selected topographic characteristics, suggesting a close connection between geometric features of snow cover and ground features. Comparing in situ SWE measurements with MN and CL shows a correlation between −0.5 and +0.5. These indexes can hence be applied in combination with in situ data and/or modelling approaches to improve spatially distributed SWE in high-alpine catchments.
{"title":"Morphological indexes to describe snow-cover patterns in a high-alpine area","authors":"Lucia Ferrarin, Karsten Schulz, Daniele Bocchiola, Franziska Koch","doi":"10.1017/aog.2023.62","DOIUrl":"https://doi.org/10.1017/aog.2023.62","url":null,"abstract":"Abstract The spatiotemporal distribution of snow affects hydrological and climatological processes at different scales. Accordingly, quantifying geometric features of snow-cover patterns is important, providing a valuable complement for snow water equivalent (SWE) modelling. This study on satellite-based morphological analysis originally uses two types of geometric indexes: (1) MN, Minkowski numbers (area (MN1), perimeter (MN2), Euler number (MN3)), and (2) CL, average chord length, to describe the morphology of Sentinel-2-derived snow-covered areas (SCAs), within the high-alpine site Zugspitze for a 5 year period. Results indicate that they capture the seasonal variability of snow-cover patterns, particularly during accumulation and ablation. Being to some degree independent from each other, MN2, MN3 and CL provide additional information upon shape, connectivity and length scale of snow cover, compared to most used indexes (e.g. fractional SCA). Correlation values up to +0.7 for MN2, +0.58 for MN3 and +0.46 for CL were observed with selected topographic characteristics, suggesting a close connection between geometric features of snow cover and ground features. Comparing in situ SWE measurements with MN and CL shows a correlation between −0.5 and +0.5. These indexes can hence be applied in combination with in situ data and/or modelling approaches to improve spatially distributed SWE in high-alpine catchments.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"204 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135112686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicolas Stoll, Pascal Bohleber, Remi Dallmayr, Frank Wilhelms, Carlo Barbante, Ilka Weikusat
Abstract Deciphering the localisation of solid and dissolved impurities on the micron-scale in glacial ice remains a challenge, but is critical to understand the integrity of ice core records and internal deformation. Here we report on the state-of-the-art in microstructural impurity research by highlighting recent progress in bringing together cryo-Raman spectroscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We show the potential of both methods and discuss possibilities to improve inter-method approaches aiming for a more holistic understanding of the evolution of impurity localisation throughout the ice column, including post-depositional processes. In this framework, we elaborate on future research priorities such as LA-ICP-MS imaging on firn samples and integrating a large cryo-cell with imaging capabilities.
{"title":"The new frontier of microstructural impurity research in polar ice","authors":"Nicolas Stoll, Pascal Bohleber, Remi Dallmayr, Frank Wilhelms, Carlo Barbante, Ilka Weikusat","doi":"10.1017/aog.2023.61","DOIUrl":"https://doi.org/10.1017/aog.2023.61","url":null,"abstract":"Abstract Deciphering the localisation of solid and dissolved impurities on the micron-scale in glacial ice remains a challenge, but is critical to understand the integrity of ice core records and internal deformation. Here we report on the state-of-the-art in microstructural impurity research by highlighting recent progress in bringing together cryo-Raman spectroscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We show the potential of both methods and discuss possibilities to improve inter-method approaches aiming for a more holistic understanding of the evolution of impurity localisation throughout the ice column, including post-depositional processes. In this framework, we elaborate on future research priorities such as LA-ICP-MS imaging on firn samples and integrating a large cryo-cell with imaging capabilities.","PeriodicalId":8211,"journal":{"name":"Annals of Glaciology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136129676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：