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Characterising the ice sheet surface in Northeast Greenland using Sentinel-1 SAR data 利用Sentinel-1 SAR数据表征格陵兰东北部冰盖表面
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-31 DOI: 10.1017/jog.2023.64
Qingying Shu, Rebecca Killick, A. Leeson, C. Nemeth, X. Fettweis, A. Hogg, David Leslie
Over half of the recent mass loss from the Greenland ice sheet, and its associated contribution to global sea level rise, can be attributed to increased surface meltwater runoff, with the remainder a result of dynamical processes such as calving and ice discharge. It is therefore important to quantify the distribution of melting on the ice sheet if we are to adequately understand past ice sheet change and make predictions for the future. In this article, we present a novel semi-empirical approach for characterising ice sheet surface conditions using high-resolution synthetic aperture radar (SAR) backscatter data from the Sentinel-1 satellite. We apply a state-space model to nine sites within North-East Greenland to identify changes in SAR backscatter, and we attribute these to different surface types with reference to optical satellite imagery and meteorological data. A set of decision-making rules for labelling ice sheet melting states are determined based on this analysis and subsequently applied to previously unseen sites. We show that our method performs well in (1) recognising some of the ice sheet surface types such as snow and dark ice and (2) determining whether the surface is melting or not melting. Sentinel-1 SAR data are of high spatial resolution; thus, in developing a method to identify the state of the surface from these data, we improve our capability to understand the variation of ice sheet melting across time and space.
格陵兰冰盖最近一半以上的质量损失及其对全球海平面上升的相关贡献可归因于地表融水径流的增加,其余部分则是冰裂和冰排放等动力过程的结果。因此,如果我们要充分了解过去的冰盖变化并对未来作出预测,那么量化冰盖融化的分布是很重要的。在本文中,我们提出了一种新的半经验方法,利用来自Sentinel-1卫星的高分辨率合成孔径雷达(SAR)后向散射数据来表征冰盖表面状况。我们将状态空间模型应用于格陵兰东北部的9个站点,以确定SAR后向散射的变化,并根据光学卫星图像和气象数据将这些变化归因于不同的地表类型。根据这一分析确定了一套标记冰盖融化状态的决策规则,并随后将其应用于以前未见过的地点。我们表明,我们的方法在(1)识别一些冰盖表面类型(如雪和暗冰)和(2)确定表面是否正在融化方面表现良好。Sentinel-1 SAR数据空间分辨率高;因此,在开发一种从这些数据中识别地表状态的方法时,我们提高了了解冰盖融化随时间和空间变化的能力。
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引用次数: 1
Remote sensing of glacier change (1965–2021) and identification of surge-type glaciers on Severnaya Zemlya, Russian High Arctic 俄罗斯高北极Severnaya Zemlya冰川变化遥感(1965–2021)和浪涌型冰川识别
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-17 DOI: 10.1017/jog.2023.60
Holly Wytiahlowsky, C. Stokes, D. Evans
Glaciers in the Russian High Arctic have undergone accelerated mass loss due to atmospheric and oceanic warming in the Barents–Kara Sea region. Most studies have concentrated on the western Barents–Kara sector, despite evidence of accelerating mass loss as far east as Severnaya Zemlya. However, long-term trends in glacier change on Severnaya Zemlya are largely unknown and this record may be complicated by surge-type glaciers. Here, we present a long-term assessment of glacier change (1965–2021) on Severnaya Zemlya and a new inventory of surge-type glaciers using declassified spy-satellite photography (KH-7/9 Hexagon) and optical satellite imagery (ASTER, Sentinel-2A, Landsat-4/5 TM and 8 OLI). Glacier area reduced from 17 053 km2 in 1965 to 16 275 in 2021 (−5%; mean: −18%, max: −100%), with areal shrinkage most pronounced at land-terminating glaciers on southern Severnaya Zemlya, where there is a recent (post-2010s) increase in summer atmospheric temperatures. We find that surging may be more widespread than previously thought, with three glaciers classified confirmed as surge-type, eight as likely to have surged and nine as possible, comprising 11% of Severnaya Zemlya's 190 glaciers (37% by area). Under continued warming, we anticipate accelerated retreat and increased likelihood of surging as basal thermal regimes shift.
由于巴伦支-卡拉海地区的大气和海洋变暖,俄罗斯高北极地区的冰川质量加速流失。大多数研究都集中在巴伦支-卡拉西部地区,尽管有证据表明东部的塞维纳亚-泽姆利亚地区的质量损失正在加速。然而,Severnaya Zemlya冰川变化的长期趋势在很大程度上是未知的,这一记录可能因浪涌型冰川而变得复杂。在这里,我们使用解密的间谍卫星照片(KH-7/9 Hexagon)和光学卫星图像(ASTER、Sentinel-2A、Landsat-4/5 TM和8 OLI)对Severnaya Zemlya的冰川变化(1965–2021)进行了长期评估,并对浪涌型冰川进行了新的清查。冰川面积从1965年的17053平方公里减少到2021年的16275平方公里(−5%;平均值:−18%,最大值:−100%),面积收缩最明显的是塞维纳亚-泽姆利亚南部的陆地冰川,那里的夏季大气温度最近(2010年代后)有所上升。我们发现,涌浪可能比之前想象的更为广泛,有三座冰川被确认为涌浪型,八座冰川有可能涌浪,九座冰川可能涌潮,占Severnaya Zemlya 190座冰川的11%(按面积计算为37%)。在持续变暖的情况下,我们预计随着基础热状态的变化,消退的速度会加快,激增的可能性也会增加。
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引用次数: 1
Calving, ice flow, and thickness of outlet glaciers controlled by land-fast sea ice in Lützow-Holm Bay, East Antarctica 南极洲东部吕措-霍尔姆湾陆地快速海冰控制的出口冰川的崩解、冰流和厚度
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-14 DOI: 10.1017/jog.2023.59
Ken Kondo, S. Sugiyama
To investigate the mechanisms driving recent changes in outlet glaciers in Antarctica, we measured the glacier front position, flow velocity and surface elevation of five outlet glaciers flowing into Lützow-Holm Bay in East Antarctica. After a steady advance from 2008 to 2015, all the glaciers synchronously retreated by 0.4–6.0 km between 2016 and 2018. The initiation of the retreat coincided with the breakup of land-fast sea ice in Lützow-Holm Bay in 2016, which resulted in the largest sea-ice loss in the region since 1998. Similar flow variations and surface elevation changes were observed near the grounding line of Shirase, Skallen and Telen glaciers. The slowdown in 2011–15 (by 13%) and the speedup in 2016–18 (by 7%) coincided with the respective increase and decrease in surface elevation. Simultaneous retreat and acceleration after the land-fast sea-ice breakup implies that sea ice has a significant influence on glacier dynamics. Thickening/thinning observed near the grounding line was attributed to a reduced/enhanced stretching flow regime during the deceleration/acceleration period. Our results demonstrate that land-fast sea ice affects not only terminus positions, but also the flow speed and ice thickness of the Antarctic glaciers.
为了探讨南极出口冰川近期变化的驱动机制,我们测量了流入南极洲东部l zow- holm湾的5个出口冰川的冰川前沿位置、流速和地表高程。经过2008年至2015年的稳步推进,所有冰川在2016年至2018年期间同步后退0.4-6.0公里。2016年,l佐-霍尔姆湾陆上海冰破裂,导致该地区自1998年以来最大的海冰损失。Shirase、Skallen和Telen冰川接地线附近也有类似的流量变化和地表高程变化。2011-15年的放缓(13%)和2016-18年的加速(7%)与地表高度的上升和下降相吻合。海冰在陆速崩解后同时后退和加速,表明海冰对冰川动力学有显著影响。在接地线附近观察到的增厚/变薄归因于减速/加速期间拉伸流态的减少/增强。研究结果表明,陆阻海冰不仅影响南极冰川的末端位置,还影响南极冰川的流速和冰厚。
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引用次数: 0
Amundsen Sea Embayment ice-sheet mass-loss predictions to 2050 calibrated using observations of velocity and elevation change 阿蒙森海海湾冰盖质量损失预测到2050年校准使用观测速度和海拔变化
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-14 DOI: 10.1017/jog.2023.57
S. Bevan, S. Cornford, Lin Gilbert, Inès N. Otosaka, Daniel F. Martin, Trystan Surawy-Stepney
Mass loss from the Amundsen Sea Embayment of the West Antarctic Ice Sheet is a major contributor to global sea-level rise (SLR) and has been increasing over recent decades. Predictions of future SLR are increasingly modelled using ensembles of simulations within which model parameters and external forcings are varied within credible ranges. Accurately reporting the uncertainty associated with these predictions is crucial in enabling effective planning for, and construction of defences against, rising sea levels. Calibrating model simulations against current observations of ice-sheet behaviour enables the uncertainty to be reduced. Here we calibrate an ensemble of BISICLES ice-sheet model simulations of ice loss from the Amundsen Sea Embayment using remotely sensed observations of surface elevation and ice speed. Each calibration type is shown to be capable of reducing the 90% credibility bounds of predicted contributions to SLR by 34 and 43% respectively.
南极西部冰原阿蒙森海隆起造成的物质损失是全球海平面上升(SLR)的主要原因,并且在近几十年来一直在增加。对未来单反的预测越来越多地使用模拟集合进行建模,其中模式参数和外部强迫在可信范围内变化。准确报告与这些预测相关的不确定性,对于有效规划海平面上升并建立防御措施至关重要。根据目前对冰盖行为的观测校准模式模拟,可以减少不确定性。在这里,我们使用表面高程和冰速的遥感观测,校准了来自阿蒙森海海湾的冰损失的BISICLES冰盖模型模拟集合。结果表明,每种校准类型都能够将SLR预测贡献的90%可信范围分别降低34%和43%。
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引用次数: 1
Ocean wave blocking by periodic surface rolls fortifies Arctic ice shelves 周期性的海面翻滚阻挡了海浪,巩固了北极冰架
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-14 DOI: 10.1017/jog.2023.58
Peter Nekrasov, D. Macayeal
The Ward Hunt and Milne ice shelves are the present-day remnants of a much larger ice shelf that once fringed the coast of Ellesmere Island, Canada. These ice shelves possess a unique surface morphology consisting of wave-like rolls that run parallel to the shoreline. Setting aside the question of how these rolls originally developed, we consider the impact of this roll morphology on the stability of the ice shelf. In particular, we examine whether periodic variations in ice-shelf thickness and water depth implied by the rolls prevent the excitation of Lamb waves in the ice shelf. Using a hierarchy of numerical models, we find that there are band gaps in the flexural and extensional modes of the ice shelf, implying the existence of frequency ranges that lack wave motion. We show that an ice shelf with rolls is able to reflect waves in these frequency ranges that are incident upon its ice front, thereby mitigating undue stress and calving. We speculate that the roll morphology provides a “fitness” for survival that explains why rolls are observed in the oldest and thickest multiyear sea ice of the Arctic.
沃德·亨特冰架和米尔恩冰架是曾经环绕加拿大埃尔斯米尔岛海岸的一个大得多的冰架的遗迹。这些冰架具有独特的表面形态,由与海岸线平行的波浪状卷组成。撇开这些卷最初是如何发展的问题,我们考虑这种卷的形态对冰架稳定性的影响。特别是,我们研究了冰架厚度和水深的周期性变化是否会阻止冰架中兰姆波的激发。利用数值模型的层次结构,我们发现在冰架的弯曲和伸展模式中存在带隙,这意味着存在缺乏波动的频率范围。我们表明,带卷的冰架能够反射这些频率范围内入射到其冰锋上的波,从而减轻不必要的应力和冰裂。我们推测,卷的形态为生存提供了一种“适应性”,这解释了为什么在北极最古老、最厚的多年海冰中可以观察到卷。
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引用次数: 0
Antarctic iceberg melt rate variability and sensitivity to ocean thermal forcing 南极冰山融化速率的可变性和对海洋热强迫的敏感性
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-14 DOI: 10.1017/jog.2023.54
E. Enderlin, C. Moffat, Emily E. Miller, Adam Dickson, Caitlin Oliver, Mariama C. Dryák-Vallies, Rainey Aberle
Changes in iceberg calving fluxes and oceanographic conditions around Antarctica have likely influenced the spatial and temporal distribution of iceberg fresh water fluxes to the surrounding ocean basins. However, Antarctic iceberg melt rate estimates have been limited to very large icebergs in the open ocean. Here we use a remote-sensing approach to estimate iceberg melt rates from 2011 to 2022 for 15 study sites around Antarctica. Melt rates generally increase with iceberg draft and follow large-scale variations in ocean temperature: maximum melt rates for the western peninsula, western ice sheet, eastern ice sheet and eastern peninsula are ~50, ~40, ~5 and ~5 m a−1, respectively. Iceberg melt sensitivity to thermal forcing varies widely, with a best-estimate increase in melting of ~24 m a−1°C−1 and range from near-zero to ~100 m a−1°C−1. Variations in water shear likely contribute to the apparent spread in thermal forcing sensitivity across sites. Although the sensitivity of iceberg melt rates to water shear prevents the use of melt rates as a proxy to infer coastal water mass temperature variability, additional coastal iceberg melt observations will likely improve models of Southern Ocean fresh water fluxes and have potential for subglacial discharge plume mapping.
南极洲周围冰山崩解通量和海洋学条件的变化可能影响了冰山向周围海洋盆地淡水通量的时空分布。然而,对南极冰山融化速度的估计仅限于公海上非常大的冰山。在这里,我们使用遥感方法估算了2011年至2022年南极洲周围15个研究地点的冰山融化速度。融化速率一般随冰山下沉而增加,并随海洋温度的大尺度变化而增加:西部半岛、西部冰盖、东部冰盖和东部半岛的最大融化速率分别为~50、~40、~5和~5 ma−1。冰山融化对热强迫的敏感性变化很大,最好的估计是融化增加~24 ma - 1°C - 1,范围从接近零到~100 ma - 1°C - 1。水切变的变化可能有助于热强迫敏感性在不同地点的明显扩散。尽管冰山融化速率对水切变的敏感性阻碍了使用融化速率作为推断沿海水团温度变化的代理,但额外的沿海冰山融化观测可能会改进南大洋淡水通量模型,并有可能进行冰下排放羽流测绘。
{"title":"Antarctic iceberg melt rate variability and sensitivity to ocean thermal forcing","authors":"E. Enderlin, C. Moffat, Emily E. Miller, Adam Dickson, Caitlin Oliver, Mariama C. Dryák-Vallies, Rainey Aberle","doi":"10.1017/jog.2023.54","DOIUrl":"https://doi.org/10.1017/jog.2023.54","url":null,"abstract":"\u0000 Changes in iceberg calving fluxes and oceanographic conditions around Antarctica have likely influenced the spatial and temporal distribution of iceberg fresh water fluxes to the surrounding ocean basins. However, Antarctic iceberg melt rate estimates have been limited to very large icebergs in the open ocean. Here we use a remote-sensing approach to estimate iceberg melt rates from 2011 to 2022 for 15 study sites around Antarctica. Melt rates generally increase with iceberg draft and follow large-scale variations in ocean temperature: maximum melt rates for the western peninsula, western ice sheet, eastern ice sheet and eastern peninsula are ~50, ~40, ~5 and ~5 m a−1, respectively. Iceberg melt sensitivity to thermal forcing varies widely, with a best-estimate increase in melting of ~24 m a−1°C−1 and range from near-zero to ~100 m a−1°C−1. Variations in water shear likely contribute to the apparent spread in thermal forcing sensitivity across sites. Although the sensitivity of iceberg melt rates to water shear prevents the use of melt rates as a proxy to infer coastal water mass temperature variability, additional coastal iceberg melt observations will likely improve models of Southern Ocean fresh water fluxes and have potential for subglacial discharge plume mapping.","PeriodicalId":15981,"journal":{"name":"Journal of Glaciology","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47849413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Geothermal heat flow from borehole measurements at the margin of Princess Elizabeth Land (East Antarctic Ice Sheet) 伊丽莎白公主地(南极东部冰盖)边缘钻孔测量的地热流
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-07 DOI: 10.1017/jog.2023.43
P. Talalay, D. Gong, Xiaopeng Fan, Yazhou Li, G. Leitchenkov, B. Li, Nan Zhang, Rusheng Wang, Yang Yang, Jialin Hong
A 198.8 m deep borehole was drilled through ice to subglacial bedrock in the northwestern marginal part of Princess Elizabeth Land, ~12 km south of Zhongshan Station, in January–February 2019. Three years later, in February 2022, the borehole temperature profile was measured, and the geothermal heat flow (GHF) was estimated using a 1-D time-dependent energy-balance equation. For a depth corresponding to the base of the ice sheet, the GHF was calculated as 72.6 ± 2.3 mW m−2 and temperature −4.53 ± 0.27°C. The regional averages estimated for this area based, generally, on tectonic setting vary from 55 to 66 mW m−2. A higher GHF is interpreted to originate mostly from the occurrence of metamorphic complexes intruded by heat-producing elements in the subglacial bedrock below the drill site.
2019年1月至2月,在中山站以南约12公里的伊丽莎白公主地西北边缘,通过冰向冰下基岩钻了一个198.8米深的钻孔。三年后的2022年2月,测量了钻孔温度剖面,并使用一维时间相关能量平衡方程估计了地热流量(GHF)。对于与冰盖底部相对应的深度,GHF计算为72.6±2.3 mW m−2,温度为-4.53±0.27°C。通常,根据构造背景估计该地区的区域平均值在55至66 mW m–2之间。较高的GHF被解释为主要源于钻井现场下方冰下基岩中由产热元素侵入的变质杂岩的出现。
{"title":"Geothermal heat flow from borehole measurements at the margin of Princess Elizabeth Land (East Antarctic Ice Sheet)","authors":"P. Talalay, D. Gong, Xiaopeng Fan, Yazhou Li, G. Leitchenkov, B. Li, Nan Zhang, Rusheng Wang, Yang Yang, Jialin Hong","doi":"10.1017/jog.2023.43","DOIUrl":"https://doi.org/10.1017/jog.2023.43","url":null,"abstract":"\u0000 A 198.8 m deep borehole was drilled through ice to subglacial bedrock in the northwestern marginal part of Princess Elizabeth Land, ~12 km south of Zhongshan Station, in January–February 2019. Three years later, in February 2022, the borehole temperature profile was measured, and the geothermal heat flow (GHF) was estimated using a 1-D time-dependent energy-balance equation. For a depth corresponding to the base of the ice sheet, the GHF was calculated as 72.6 ± 2.3 mW m−2 and temperature −4.53 ± 0.27°C. The regional averages estimated for this area based, generally, on tectonic setting vary from 55 to 66 mW m−2. A higher GHF is interpreted to originate mostly from the occurrence of metamorphic complexes intruded by heat-producing elements in the subglacial bedrock below the drill site.","PeriodicalId":15981,"journal":{"name":"Journal of Glaciology","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2023-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42955850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A comparison of contemporaneous airborne altimetry and ice-thickness measurements of Antarctic ice shelves 南极冰架同时期空中测高和冰厚测量的比较
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-03 DOI: 10.1017/jog.2023.49
Allison M. Chartrand, I. Howat
Estimates of ice shelf mass loss are typically based on surface height measurements, assuming hydrostatic equilibrium and estimated firn thickness. Recent investigations, however, challenge the assumption that ice shelves are freely floating, particularly in proximity to narrow structures such as basal channels and shear margins. We compare contemporaneous measurements of Antarctic ice shelf thickness, from ice-penetrating radar, to freeboard height, from laser altimetry, acquired during multiple airborne surveys. On average, the hydrostatic thickness differs from observed thickness by at least ~17 ± 98 m, but this difference varies well beyond the propagated error within and among ice shelves, and depends on the corrections applied. We find that uncertainty in firn thickness can account for most, but not all, of the imbalance. Overall, errors in hydrostatic thickness do not significantly impact estimated basal melt rates. Our results indicate that localized approaches to estimating ice shelf thickness and rates of change are not applicable at large scales, and vice versa, and point to the need for more abundant and accurate firn and ice thickness measurements to improve estimates and predictions of ice shelf mass loss.
冰架质量损失的估计通常基于表面高度测量,假设流体静力平衡和估计的冷杉厚度。然而,最近的调查挑战了冰架自由漂浮的假设,特别是在狭窄结构(如基底通道和剪切边缘)附近。我们比较了在多次航空调查中获得的南极冰架厚度的同期测量值,从探冰雷达到干舷高度,从激光测高。平均而言,静水压厚度与观测到的厚度相差至少~17±98 m,但这种差异远远超出了冰架内部和冰架之间的传播误差,并取决于所应用的校正。我们发现,冷杉厚度的不确定性可以解释这种不平衡的大部分,但不是全部。总体而言,静水压厚度的误差不会显著影响估计的基本熔体速率。我们的研究结果表明,估计冰架厚度和变化率的局部方法不适用于大尺度,反之亦然,并指出需要更丰富、更准确的firn和冰厚度测量,以改进对冰架质量损失的估计和预测。
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引用次数: 0
Ice-flow perturbation analysis: a method to estimate ice-sheet bed topography and conditions from surface datasets 冰流摄动分析:一种从地表数据集估计冰盖床地形和条件的方法
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-08-03 DOI: 10.1017/jog.2023.50
Helen Ockenden, R. Bingham, Andrew Curtis, D. Goldberg
One of the largest contributors to uncertainty in predictions of sea-level rise from ice-sheet models is a lack of knowledge about the bed topography beneath ice sheets. Bed topography maps are normally made by interpolating between linear radar surveys using methods that include kriging, mass conservation and flowline diffusion, all of which may miss influential mesoscale (2–30 km) bedforms. Previous works have explored an Ice-Flow Perturbation Analysis (IFPA) approach for estimating bed topography using the surface expression of these mesoscale bedforms. Using regions of Pine Island Glacier that have been intensively surveyed by ice-penetrating radar as test sites, and a refined IFPA methodology, we find that IFPA detects bedforms capable of influencing ice flow which are not represented in Bedmachine Antarctica and other interpolated bed products. We further explore the ability of IFPA to estimate relative bed slipperiness, finding higher slipperiness in the main trunk and tributaries. Alongside other methods which estimate ice thickness, bed topography maps from IFPA have the potential to constrain projections of future sea-level rise, especially where radar data are sparse.
在根据冰盖模型预测海平面上升时,造成不确定性的最大因素之一是缺乏对冰盖下床地形的了解。河床地形图通常是在线性雷达测量之间进行插值绘制的,使用的方法包括克里格法、质量守恒法和流线扩散法,所有这些方法都可能错过有影响的中尺度(2-30公里)河床。以前的工作已经探索了冰流摄动分析(IFPA)方法,利用这些中尺度床型的表面表达来估计床地形。利用冰透雷达密集调查的松岛冰川区域作为测试点,并使用改进的IFPA方法,我们发现IFPA检测到能够影响冰流的床型,而这些床型在Bedmachine南极洲和其他插值床型产品中没有体现出来。我们进一步探索了IFPA估算相对地层滑度的能力,发现主干流和支流的滑度较高。与其他估算冰厚的方法一样,IFPA的床地形图有可能限制对未来海平面上升的预测,特别是在雷达数据稀少的地方。
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引用次数: 0
JOG volume 69 issue 276 Cover and Back matter JOG卷69期276封面和封底
IF 3.4 3区 地球科学 Q1 Earth and Planetary Sciences Pub Date : 2023-07-28 DOI: 10.1017/jog.2023.56
{"title":"JOG volume 69 issue 276 Cover and Back matter","authors":"","doi":"10.1017/jog.2023.56","DOIUrl":"https://doi.org/10.1017/jog.2023.56","url":null,"abstract":"","PeriodicalId":15981,"journal":{"name":"Journal of Glaciology","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42287508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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Journal of Glaciology
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