buchroithner - multitemporal remote sensing-based 3d mapping of glacier changes in remote areas

TU Dresden >> Faculty of Environmental Sciences>> Institute of Cartography

Multitemporal remote sensing-based 3D mapping of glacier changes in remote

areas

Manfred F. Buchroithner, Tino Pieczonka, Nicolai Holzer, Benjamin Schröter

Technische Universität Dresden, Institut für Kartographie


Introduction

Manfred Buchroithner Multitemporal remote sensing-based 3D mapping

of glacier changes in remote areas

Background

Glacial melt significantly contributes to the water resource.

Lack of long-term measurements of glacier mass budgets

Existing studies are focusing on single glaciers or small catchments only:

- Ak-Shirak (Aizen et al. 2007, GaPC)

- Tomur region (Pieczonka et al. 2013, RSE; Wang et al. 2013, QI)

- Inylchek glacier (Shangguan et al. 2014, TCD)

- Gurla Mandhata (Holzer et. al., submitted to RSE)

- Muztag Ata (Holzer et al., in prep. for TC)

No region-wide geodetic mass balance studies for many regions in High Asia since the 1970s!


Introduction

Cartosat-1 2007

Aerial imagery 1984Corona 1970

The cryosphere has changed tremendously during the last

decades

We have to know the past in order to understand the presence!



Elevation difference of all HMA glaciers 2003 – 2009 based on ICESat


Introduction

Gardner et al. (2013), Science

clear mass loss

clear mass loss

heterogeneous mass changescl

ear

mass

loss

1973 – 2013

Þ Geodetic assessments to improve spatial and temporal

coverage




Introduction

Mass Budget Data for Tien Shan (Sorg et al. 2012)

23

4

6

51

Available data from in-situ measurements (and modelling)

Tien Shan

PamirKarakorum

Hindukush



Mass budget data published by Yao et al. (2012)


Data

KH-4 Corona, KH-7 Gambit, KH-9 Hexagon

Historical satellite imagery




Study Region




Study Region

Tino Pieczonka et al. The suitability of historical optical satellite imagery

for investigations of the cryosphere


Study Region



Terrestrial camera system, Zhadang Glacier 2010/2011


Data

Data characteristics

KH-4 KH-7 KH-9

First launch 1959 1963 1971

Geometric. res.

1.8-7.6 m 0.6 – 1.2 m 6-9 m

Radiometric res.

8 Bit 8 Bit 8 Bit

Spectral res. Panchromatic Panchromatic Panchromatic

Coverage 15 x 210 – 42 x 580 km

ca. 20 x 150 km

250 x 125 km

Preprocessing RectificationGeoreferencing

RectificationGeoreferencing

RectificationGeoreferencing



Forward (FWD)

approx. 60% overlap

Aft (AFT)


Camera KH-4

KH-4 Corona

Initial objectives: Gathering information about the military strenght of the former Soviet Union

Panoramic distortion plus motionSohn et al. (2002)




Results KH-4

Everest Region

DEM ComparisonCartosat-1 – KH-4B

Corona(2007 – 1970)

Bolch et al. (2011), The CryospherePieczonka et al. (2011), ISPRS

Glacier mass loss: almost 0.6 km³

Glaciers thinning: 0.37±0.27 m a-1

Specific mass balance: -0.32±0.08 m w.e.a-1




Camera – KH-7

KH-7 Gambit

Monocamera system

-> random stereoscopic coverage

KH-7 vs. KH-4:

High resolution 77 inch focal length (cf. 24 inch KH-4) telescopic strip camera system ... large area of coverage and improved ground resolution (<1 m vs. 8 m)

18 000 panchromatic and 230 color images acquired

-> only few of them in stereo



Glacier length changes from 1964 to 2013 at Gurla Mandhata (Holzer et al., sumitted to RSE)

KH-7 Gambit-1 ortho image of 5 Dec. 1964 vs. Pleiades ortho image of 18 Oct. 2013


Camera KH-9

KH-9 Hexagon

Camera design of KH-9 comparable to that of LFC (Surazakov and Aizen, 2009)

-> 23x46 cm frame, 30.5 cm focal length

-> 1058 reseau crosses vs. 45 (LFC), four fiducials vs. 12 (LFC)




Preprocessing KH-9

KH-9 Hexagon

Reconstruction of interior image geometry by use of reseau grid coordinates

Basic assumptions: Cross spacing 1 cm, centre cross undistorted

Correction of film distortion based on 2nd order polynomial

Distortion vectors from actual to theoretic reseau

grid coordinates

Bicubic interpolation/Inpaint



1987-03-24 1987-07-22

Results KH-9

Length Changes 1976-2005 (Nyainqentanglha/Tibet)

Zhadang: 225 ± 45m (~8m/a)

480 ± 45m (~17m/a)

430 ± 45m (~15m/a)

125 ± 45m (~4m/a)





Glacier Area Changes

MB: -0.52 ± 0.17 m w.e./a MB: -0.34 ± 0.18 m

w.e./a

MB: -0.22 ± 0.17 m w.e./a

Glacier retreat 1975-2008 3.7±4.8 % with decreasing shrinkage rates west to east.




Multitemporal DTM



Glacier mass budgets

Tomur-Inylchek region

ID Glacier MB [m w.e.a-

1]

Δa a-1

[%]ΔhDebris a-1

[m a-1]

9 Kaindy -0.28±0.17 -0.14±0.14 -1.25±0.20

11 Tomur -0.57±0.17 -0.02±0.08 -1.50±0.20

12 South In.

-0.27±0.17 -0.07±0.05 -0.87±0.20

13 North In.

-0.20±0.17 +0.13±0.08

+0.36±0.20

14 Koxkar -0.34±0.18 -0.03±0.08 -0.78±0.21



Glacier tongue of Kaindy glacier with exposed ice cliffs

Photo: T. Pieczonka, 2012

Results KH-9

1999 (SRTM3) – 2009 (SPOT5)

Glacier Volume Change (Tomur Region)

1976 (KH-9) – 2009 (SRTM3)

Pieczonka et al. (2013), RSE

Mass budget 1976-2009-0.35 ± 0.15 m w.e./a

Mass budget 1999-2009-0.23 ± 0.19 m w.e./a







Long-term glacier variations at Muztag Ata (eastern Pamir) from 1973 – 2013 (Holzer et al, in prep. for TC)

Glaciers shrinkage from 274.3 ± 10.6 km² (1973) to 272.7 ± 1.0 km² in 2013 (-0.02±0.1%a-1) is insignificant. Mass budgets are almostbalanced from 1973-2013 (-0.01±0.30 m w.e.a-1), but slightly more negative before 1999 and more positive afterwards.


High resolution Digital Elevation Models (1m) from Pléiades stereo imagery at Muztag Ata and Gurla Mandhata (Holzer et al, in prep. for TC)

Hillshade showing the middle part of the debris covered Kekesayi Glacier at Muztag Ata in the east Pamir.

DEM Difference images to SRTM-3 after post-processing for glacier mass balance calculation and uncertainty assessment

Glacier mass balance of Gurla Glacier: -0,21±0.18 m w.e.a-1 determined from both Pléiades and TanDEM-X DEMs relative to SRTM-3

DEM of Pléiades (2013) to SRTM-3 (1999) DEM of TanDEM-X (2012) to SRTM-3 (1999)


Glacier variations at Gurla Mandhata (Naimona’nyi), Tibet: a multi-sensoral approach including TanDEM-X, Pléiades and KH-7 Gambit-1 (Holzer et al., sumitted to RSE)

DEM of Pléiades (2013) to SRTM-3

(1999)

Periodic Glacial Lake Outburst Floods threatening the oldest Buddhist monastery in NW Nepal

(Kropáček et al, in prep. for NHESS)


Glacier mass balance of Halji Glacier from Pléiades to SRTM-3: -0.40±0.30 m w.e.a-1


Conclusions

Conclusions

- Knowledge especially for the last decade significantly improved by using historical satellite images.

- High potentials of new remote sensing datasets for glaciological studies (e.g. Pléiades, TanDEM-X)

- Careful co-registration is required in order to determine reliable glacier mass budgets.

- On average, significant glacier mass loss across High Asia since the 1970s, but there are also advancing/surging glaciers.

- More studies are needed to extend the coverage both in space and especially in time.



TU Dresden >> Faculty of Forest, Geo and Hydro Sciences >> Institute of Cartography

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buchroithner - multitemporal remote sensing-based 3d mapping of glacier changes in remote areas

Data & Analytics

remote areasmanfred

remote areasbackgroundglacial

d mappingof glacier

zhadang glacier

remote areasmass budget

glacier mass loss

inch kh

instereoglacier length