Improved geodetic glacier mass balance measurements by integrating remote sensing, surface mass balance and firn compaction modelling - a case study from James Ross Island, Antarctica

通过集成遥感、表面质量平衡和冰雪压实模型改进大地冰川质量平衡测量——以南极洲詹姆斯罗斯岛为例

基本信息

批准号：
282369042
负责人：
Professor Dr. Matthias Holger Braun
金额：
--
依托单位：
Institut für Geographie
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2016
资助国家：
德国
起止时间：
2015-12-31 至 2018-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/282369042?language=en
关键词：
Improved geodetic glacier mass balance

项目摘要

The project targets on the improvement of geodetic glacier mass balances. Besides of an improvement of the absolute precision we aim at a general improvement of the error quantification and error estimation. In a first setp elevation and volume changes will be computed by differencing digital elevation models (DEMs) from different dates and sources. The DEMs will be generated by photogrammetry or SAR interferometry (especially using data of the German TanDEM-X mission). The current limitations of the geodetic method result from the unquantified penetration depth of the radar signal into dry snow or a frozen snow cover as well as from the conversion of volume to mass by assuming a fixed density or specific density profile. We propose to improve the conversions by coupling a glacier surface mass balance and firn compaction model with the remote sensing results. In order to initialise and validate the model we will rely on field surveys as well as a profound database of the applicant as well as the Czech and Argentine counterparts. We will quantify the effects of x-band radar penetration depth by comparing summer and winter situations as well as comparison to in-situ GNSS measurements. In addition, we will compare the results of the geodetic method with the Input-Output (or flux gate) approach. The project is carried out in close collaboration of Czech partners from Brno and Prague University as well as our counterparts from the Instituto Antártico Argentino. We propose James Ross Island - located at the northeaster tip of the Antarctic Peninsula - as study site. Despite of its location in Antarctica, we primarily aim at methodological developments that can be transferred to other regions and locations. The proposed study site is favourable due to its database and the joint preparatory work as well as the international collaboration and logistic access almost ideal conditions for the proposed work that does not lead to significant additional costs in comparison to locations with comparable glacier sizes. Specifically, the preparatory work shows that the observed elevation changes are quite heterogeneous on the different glaciers enabling the analysis of changes in different magnitudes, directions and underlying mechanisms within a very narrow area in addition to different meteorological conditions. This situation is very specific to the proposed site and provides ideal conditions for method development.

该项目的目标是改善大地冰川质量平衡，除了提高绝对精度外，我们的目标是总体改善误差量化和误差估计，首先将通过差分数字高程模型计算高程和体积变化。来自不同日期和来源的 DEM 将通过摄影测量或 SAR 干涉测量（特别是使用德国 TanDEM-X 任务的数据）生成。目前大地测量方法的局限性。雷达信号对干雪或冰冻雪盖的未量化穿透深度，以及通过假设固定密度或特定密度剖面将体积转换为质量，我们建议通过耦合冰川表面质量平衡和冰雪来改进转换。为了初始化和验证该模型，我们将依靠申请人以及捷克和阿根廷单位的丰富数据库来量化 x 波段雷达的影响。比较夏季和冬季情况的渗透深度此外，我们还将比较大地测量方法与输入输出（或磁通门）方法的结果。该项目是在布尔诺和布拉格的捷克合作伙伴的密切合作下进行的。我们建议将位于南极半岛东北端的詹姆斯罗斯岛作为研究地点，尽管它位于南极洲，但我们的主要目标是大学和阿根廷南极研究所的礼物。拟议的研究地点是有利的，因为其数据库和联合筹备工作以及国际合作和后勤通道几乎是拟议工作的理想条件，不会导致重大成果。具体来说，准备工作表明，不同冰川上观测到的海拔变化非常不均匀，除了可以分析非常狭窄的区域内不同幅度、方向和潜在机制的变化。不同气象这种情况对于所提议的地点来说是非常具体的，并为方法开发提供了理想的条件。