The Stable State of Glaciers in Recent Decades in the Western Kunlun Shan, Northwestern

Tibetan Plateau

Liu Shiyin, Bao Weijia, Wei Junfeng, Zhang Zhen, Feng Tong, Xu Junli, and Guo Wanqin

State Key Laboratory of Cryospheric Science, Cold and Arid Regions Environmental and

Engineering Research Institute, Chinese Academy of Sciences

Presented by Tino Pieczonka [Institute of Cartography, TU Dresden]

Background

West Kunlun Shan

Western Kunlun

Liu Shiyin

Background

Jacob et al. (2012) GRACE Jan 2003 - Dec 2010 Mass change of glaciers in the northwestern Tibetan Plateau: -1±5 Gt a−1

Western Kunlun

Liu Shiyin

Background

Gardelle et al. (2012, 2013) 1999~2011 SPOT5-SRTM: Glaciers show mass gain in NW Tibetan Plateau 0.10±0.16 m yr-1

~ 0.14±0.13 m yr−1

Western Kunlun

Liu Shiyin

Background

(Gardner et al., 2013; the high-mountain Asia (HMA), 2003-2009, ICESat GLAS)

(Neckel et al., 2014; the Tibetan Plateau 2003–2009, ICESat GLAS)

Western Kunlun

Liu Shiyin

Background

Kääb et al. (2014) ICESat (2003~2008) – SRTM3: 0.05±0.07m a−1 for West Kunlun Shan

Western Kunlun

Liu Shiyin

Background

In the first decade of the 21th century: Stable conditions and mass gain in western Kunlun

Glacier area change rates are, however, not consistent between

different studies

1970-2001; Shangguan et al. (2007) 1991-2001; Shangguan et al. (2007) 1991-2009; Ji et al. (2013) 1991-2001; Ji et al. (2013) 1970s-2009; Wei et al. (2014)

What was the status of glaciers in the region during the last four decades?

Western Kunlun

Liu Shiyin

Data & Method

Data Glacier outlines Modified first glacier inventory derived from topographic maps (1:100.000)

based on aerial photos acquired during 1968-1971 Second glacier inventory based on Landsat images acquired in 2010±3 Satellite imagery Landsat TM images from the 1990s (path/row 145/35 and 145/36) Elevation data 1999 SRTM3 & 2003-2009 ICESat GLAS Snow data MOD10A1 albedo product for the period 2003-2013

Western Kunlun

Liu Shiyin

Data & Method

Uncertainty assessment Uncertainty of glacier area change [Ec ] - E1 and E2 are glacier mapping

uncertainties for period 1 and period 2. EA is the area uncertainty along the boundary of a glacier under consideration of

topographic map resolution and its co-registration error to Landsat images. The uncertainty caused by image to image co-registration is assumed to be zero.

Western Kunlun

Liu Shiyin

Uncertainty assessment Uncertainties of glacier area changes for the Western Kunlun mountain range

Total area in 1968 (km2)

Area change uncertainty (%)

Western Kunlun 2822 ±3.1

Data & Method

Western Kunlun

Liu Shiyin

Results

Glacier changes in the WKS range during the 1970s–2010s

Western Kunlun

Liu Shiyin

-0.08

Results

The most obvious retreating and advancing glaciers in the period 1968-2010 in the Western Kunlun

Western Kunlun

Liu Shiyin

Results

32 glaciers (1265.49 km2) advanced during 1968 and 2011 in western Kunlun, but they have also lost a total area of 19.26 km2。

Western Kunlun

Liu Shiyin

Results

24 advancing glaciers in the 1990-2011 period with an area increase of 9.5km2

Zhongfeng Glacier

Duota Glacier

Zhongfeng Glacier

Duofeng Glacier Kunlun Glacier

Xiyulong Glacier

Western Kunlun

Liu Shiyin

Results

Expansion of glaciers in the Western Kunlun after 1990

Year

Rat

io o

f gl

acie

r ar

ea a

nd t

he a

rea

in t

he 1

970s

1960 1980 2000 2020

1

.99

.98

.97

.96

.95

Western Kunlun

Liu Shiyin

Results

Mass balance ICESat GLAS (Ice, Cloud, and land Elevation Satellite, Geoscience Laser Altimeter System) GLA14 (Global Land Surface Altimetry Data)

- Shuttle Radar Topography Mission (SRTM) v3 - Glacier outlines of the second glacier inventory

Total 34000 GLAS footprints of the 17 missions during Feb 22, 2003 to Apr. 6, 2009

Western Kunlun

Liu Shiyin

Results

Glacier dynamics (2003-2011) 8 surge-type glaciers were excluded from the analysis

(Yasuda and Furuya, 2013)

Western Kunlun

Liu Shiyin

Results

Mass changes of glaciers in the Western Kunlun 2003-2009: 43 glaciers investigated with ICESat GLAS -> positive balance of

0.23±0.24 m w.e. a-1

Total mass gain for the entire West Kunlun Shan mountain range (including surge-type glaciers) was

0.71±0.62 Gt a-1 [mass change rate of 0.23±0.24 m w.e. a-1]

Region dh trend in accumulation area (m/a)

dh trend in ablation

area (m/a)

dh as a whole (m/a)

Mass balance on glaciers with GLAS

track (m w.e./a)

Area of GLAS

passed glaciers (km2)

WKS 0.42±0.09 0.01±0.10 0.22±0.07 0.23±0.24 1020 North slope

of WKS 0.42±0.10 -0.09±0.11 0.23±0.07 0.20±0.26 811

south slope of WKS 0.42±010 0.05±0.12 0.20±0.08 0.24±0.27 209

Western Kunlun

Liu Shiyin

ELA 5930 m (Ageta et al., 1989)

Results

Surface elevation change derived by GLAS altimetry during 2003-2009 in the Western Kunlun Mts.

4

5

6

7

8

9

10

11

2003/3/1 2004/3/1 2005/3/1 2006/3/1 2007/3/1 2008/3/1 2009/3/1

dh (

m)

Date

Western Kunlun

Liu Shiyin

Results

Is the mass gain trend validated? MODIS albedo (MOD10A1) for the period 2003-2013 - > Albedo threshold of 0.55 to discriminate snow from ice

(Greuell et al., 2007） Snowline -> Lowest elevation where SCP (snow cover probability) exceeds

90%

Western Kunlun

Liu Shiyin

Results

Frequency of days with snow cover in 2008 and 2013. The snowline elevations were obviously different for years with maximum and

minimum snow cover.

Western Kunlun

Liu Shiyin

Results

Yearly pattern of snow cover on glaciers in Western Kunlun

Western Kunlun

Liu Shiyin

Results

y = 0.1808x + 5987.2 R² = 0.0002

5,860

5,880

5,900

5,920

5,940

5,960

5,980

6,000

6,020

6,040

6,060

6,080

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

Elev

atio

n [

m a

.s.l.

]

Year

Mean elevation of snow line

Linear (Mean elevation of snow line)

A slight increase in snowline elevations since 2003

Western Kunlun

Liu Shiyin

Conclusions

Glacier area in Western Kunlun has decreased by 3.4±3.1% during 1968-2010.

Glacier advance since 1990 decelerated the general trend of glacier shrinkage in the region.

Nearly stable conditions of glaciers in the recent decade might be a result of positive mass balances as indicated by surface elevation and snowline elevation changes.

Western Kunlun

Liu Shiyin

Thank you for your attention!

Any questions?

liusy@lzb.ac.cn tino.pieczonka@tu-dresden.de

Bao, W., Liu, S., Wei, J. and others (2015), Journal of Mountain Science, 12(2), 344-357.