Surface topography and massflux of the Antarctic ice sheet in western Dronning Maud Land, derived by differential SAR interferometry

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Surface topography and massflux of the

Antarctic ice sheet in western Dronning Maud Land, derived by differential SAR interferometry

R. Drews (1), W. Rack (2), C. Wesche (1), D. Steinhage (1)

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Introduction

Methodology

Accuracy Evaluation

Surface Elevation & Ice Dynamics

Objectives

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Develop a new DEM via DinSAR

•

Derive 3D – Flowfields

•

Estimate Mass Flux into the Ekströmisen

•

Map Accumulation

. Ekströmisen

DML, Antarctica

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Data Set

W - Dronning Maud Land, Antarctica

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116 SAR scenes from ERS-1/ERS-2

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19 digital elevation models

•

area ~ 130 000 km²

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Introduction

Methodology

Accuracy Evaluation

Methodology

SAR Processors

•

PAFs

•

MSP (Gamma Remote Sensing)

•

APP (EarthView)

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Interferometric SAR

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Introduction

Methodology

Accuracy Evaluation

Differential SAR Interferometry

Icesat GCPs

DEM

1D - Disp. 3D - Disp.

Int

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Mosaic

(50x50) m grid

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Introduction

Methodology

Accuracy Evaluation

Mosaic

Tr ac k 0 45

Tr ac k 0 31

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Mosaic

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Introduction

Methodology

Accuracy Evaluation

Mosaic

Track 407 Frame 5157 Track 407 Frame 5175

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Processing Uncertainties

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Introduction

Methodology

Accuracy Evaluation

Processing Uncertainties

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Processing Uncertainties

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Introduction

Methodology

Accuracy Evaluation

Comparison with GCPs

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Airborne Laser Altimetry

•

Kinematic GPS

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Comparison with GCPs

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Introduction

Methodology

Accuracy Evaluation

Surface Elevation & Ice Dynamics

3 D - Flowfields

Mass flux: 3.45 · 10

³

Gt/a

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Boxmodel

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Introduction

Methodology

Accuracy Evaluation

Surface Elevation & Ice Dynamics

Boxmodel

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Summary

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Generation of high resolution DEM for Interferometry

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Difference field reveals processing and other external errors

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Displacement maps have been used for mass flux estimates

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Mapping of accumulation with satisfactory prelim. results

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Introduction

Methodology

Accuracy Evaluation

Comparison GPS

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Boxmodell

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Introduction

Methodology

Accuracy Evaluation

SAR Interferometry

Mixed interferogramm with topography and displacement

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Processing Uncertainties

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Introduction

Methodology

Accuracy Evaluation

Comparison with GPS

kinematic GPS

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traverse from Neumayer to Kohnen

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vertical accuracy < 1 m

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Surface topography and massflux of the Antarctic ice sheet in western Dronning Maud Land, derived by differential SAR interferometry