Geodetic glacier-averaged mass changes in the Mt.Xixabangma area in 1974-2000 and 2000-2017 (V1.0)

The data set involved geodetic annual glacier-averaged mass balance and mass change data atMt.Xixiabangma areasin the Himalayas from 1974 to 2017. It is stored in the ESRI vector polygon format and is composed of two periods, which includes surface elevation difference between 1974-2000 (DH1974-2000, from KH-9 DEM1974 and SRTM DEM2000), surface elevation difference between 2000-2017(DH2000-2017, by DinSAR techniquesfrom SRTM DEM2000 and TSX/TDX data in 2017). KH-9 DEM is a DEM of the study area in 1974, which was generated from three scenes of optical stereo pairs from KH-9. Geodetic glacier mass change was calculated by DH above, glacier cover vector data from TPG1976/CGI2/RGI6.0 with ice density of 850 ± 60 kg m−3. The attribute data included: GLIMSId means the glacier code from GLIMS data base, Area(km2)is the glacier area by km2, area_m2 is glacier area by (m2), the glacier name, EC74_2000, the surface elevation change rate from 1974 to 2000(m a-1), EC00_2017, the surface elevation change rate from 2000 to 2017 (m a-1), MB74_2000, the geodetic glacier mass balance between 1974 and 2000(m w.e. a-1),MB00_2017, the geodetic glacier mass balance between 2000 and 2017(m w.e. a-1).MC74_2000, the geodetic glacier mass change from 1974 to 2000 (m3w.e. a-1), MC00_2017, the geodetic glacier mass change from 2000 to 2017(m3 w.e. a-1). Ut_EC74_00 is the uncertainty of glacier surface elevation change(m a-1) in 1974-2000、Ut_MB74_00, is the uncertainty of glacier mass balance for each glacier(m w.e. a-1)in 1974-2000,Ut_MC74_00, is the uncertainty of glacier mass change for each glacier(m3w.e. a-1)in 1974-2000. Ut_EC00_17,is the uncertainty of glacier surface elevation change in 2000-2017(m a-1),Ut_MB00_17,is the uncertainty of glacier mass balance for each glacier in 2000-2017(m w.e. a-1),Ut_MC00_17 is the uncertainty of glacier mass change for each glacier in 2000-2017(m3 w.e. a-1).This data set is used for the study glaciers melting and its hydrological effects in the Central Himalayas.It also could be used in studies of climatic change and disasters research in the Himalayas.

0 2020-07-22

Geodetic glacier mass changes in Ponkar area in 1974-2000 and 2000-2014 (V1.0)

The data set involved geodetic annual glacier-averagedmass balance and mass change data at the Ponkar area in Nepal on the Southern slope of the Himalayas from 1974 to 2014. It is stored in the ESRI vector polygon format and is composed of two periods, which includes surface elevation difference between 1974-2000 (DH1974-2000, from KH-9 DEM1974 and SRTM DEM2000), surface elevation difference between 2000-2014 (DH2000-2014,by DinSAR techniques from SRTM DEM2000 and TSX/TDX data in 2014). KH-9 DEM is a DEM of the study area in 1974, which was generated from three scenes of optical stereo pairs from KH-9. Geodetic glacier mass change was calculated by DH above, glacier cover vector data from TPG1976/CGI2/RGI6.0 with ice density of 850 ± 60 kg m−3. The attribute data included: GLIMSId means the glacier code from GLIMS data base, the glacier_area(m2)、Area(km2), the glacier name, EC74_2000, the surface elevation change rate from 1974 to 2000(m a-1), EC00_2014, the surface elevation change rate from 2000 to 2014 (m a-1), MB74_2000, the geodetic glacier mass balance between 1974 and 2000(m w.e. a-1),MB00_2014, the geodetic glacier mass balance between 2000 and 2014(m w.e. a-1).MC74_2000, the geodetic glacier mass change from 1974 to 2000 (m3w.e. a-1), MC00_2014, the geodetic glacier mass change from 2000 to 2014(m3w.e. a-1). Ut_EC74_00 is the uncertainty of glacier surface elevation change(m a-1) in 1974-2000、Ut_MB74_00, is the uncertainty of glacier mass balance for each glacier(m w.e. a-1)in 1974-2000,Ut_MC74_00, is the uncertainty of glacier mass change for each glacier(m3w.e. a-1)in 1974-2000. Ut_EC00_14,is the uncertainty of glacier surface elevation change in 2000-2014(m a-1),Ut_MB00_14,is the uncertainty of glacier mass balance for each glacier in 2000-2014(m w.e. a-1),Ut_MC00_14 is the uncertainty of glacier mass change for each glacier in 2000-2014(m3 w.e. a-1). This data set is used for the study glaciers melting and its hydrological effects in Ponkar area in Nepal in the Southern slope of the Himalayas. It also could be used in studies of climatic change and disasters research in the Himalayas.

0 2020-07-22

Glacier mass storage changes of 71 pieces of glaciers in the east section of Yigongzangbu, Southeast Tibetan Plateau in 2000-2014

The data involved geodetic glacier mass change of 71pieces of glaciers during 2000-2014 in the east of the Yigongzangbu, Southeast Tibetan Plateau. It is stored in the ESRI vector polygon format.Glacier-averaged mass balance (m w.e.a-1) was calculated by the surface elevation difference between 2000-2014 ( Dh2000-2014)、glacier coveraged vector data (CGI2/TPG1976/RGI6.0) and ice density of 850 ± 60 kg m−3. Dh2000-2014 is obtained from surface elevation change by D-InSAR technique from a pair of TSX / TDx SAR images on February 7, 2014 and SRTM DEM. CGI2/TPG1976/RGI6.0 were used to extract glacier boundary and GLIMS-ID. SRTM DEM is the reference DEM and datum DEM with spatial resolution 30m. The attribute data includes GLIMS-ID, Area,EC_m_a-1,,MB_m w.e.a-1, MC_m3 w.e.a-1, MC_Gt.a-1, Uncerty_EC, Uncerty_MB, UT_MCm3w.e. a-1. Respectively, EC_m_a-1,,is the glacier-averaged annual elevation change during 2000-2014(m a-1),MB_m w.e.a-1, is glacier-averaged annual mass balance during 2000-2014(m w.e.a-1), MC_m3 w.e.a-1, is glacier-averaged annual mass change during 2000-2014 (m3 w.e.a-1), MC_Gt.a-1,is glacier-averaged annual mass change during 2000-2014 (Gt.a-1)Uncerty_EC is the uncertainty of glacier surface elevation change(±m a-1)、Uncerty_MB ,is the uncertainty of glacier mass balance(±m w.e. a-1),UT_MCm3w.e. a-1, is the uncertainty of glacier mass change(±m3w.e. a-1)。The data sets could be used for glacier change, hydrological and climate change studies in the southeast of Tibetan Plateau.

0 2020-07-21

Geodetic Glacier mass changes in Naimo'Nanyi area in 1974-2000 and 2000-2013 (V1.0)

The data involved two periods of geodetic glacier mass storage change of Naimona’Nyi glaciers in the western of Himalaya from 1974-2013 (unit: m w.e. a-1). It is stored in the ESRI vector polygon format. The data sets are composed of two periods of glacier surface elevation difference between 1974-2000 and 2000-2013, i.e. DHSRTM2000-DEM1974(DH2000-1974)、DHTanDEM2013-SRTM2000(DH2013-2000). DH2000-1974 was surface elevation change between SRTM2000 and DEM1974, i.e. the earlier historical DEM (DEM1974, spatial resolution 25m) was derived from 1:50,000 topographic maps in October 1974(DEM1974,spatial resolution 25m). The uncertainty in the ice free areas of DH2000-1974 was ±0.13 m a-1. The surface elevation difference between 2000-2013 (DH2000-2013, by DinSAR techniques from SRTM DEM2000 and TSX/TDX data on Oct.17th in 2013) The uncertainty in the ice free areas of DH2013-2000 was ±0.04 m a-1. Glacier-averaged annual mass balance change (m w.e.a-1) was averaged annually for each glacier, which was calculated by DH2000-1974/DH2013-2000, glacier coverage area and ice density of 850 ± 60 kg m−3. The attribute data includes Glacier area by Shape_Area (m2), EC74_00, EC00_13, i.e. Glacier-averaged surface elevation change in 1974-2000 and 2000-2013(m a-1), MB74_00, MB00_13 i.e. Glacier-averaged annual mass balance in 1974-2000 and 2000-2013 (m w.e.a-1), and MC74_00, MC00_13, Glacier-averaged annual mass change in 1974-2000 and 2000-2013 (m3 w.e.a-1), Uncerty_MB, is the uncertainty of glacier-averaged annual mass balance(m w.e. a-1), Uncerty_MC, is the Maximum uncertainty of glacier-averaged annual mass change(m3 w.e. a-1). The data sets could be used for glacier change, hydrological and climate change studies in the Himalayas and High Mountain Asia.

0 2020-07-21

The third polar area glacier surface elevation change data product v1.0

The recent glacial changes in the third polar region have become the focus of the governments of the surrounding countries because of their important significance to the downstream water supply. Based on SRTM acquired in 2000 and aster stereo image pairs before and after 2015, more than 40 Typical Glaciers in the third polar region were selected to estimate the glacial surface elevation in corresponding period. This product estimates the surface elevation changes of more than 14000 glaciers in the third polar region in 2000-2015s, and the investigated area accounts for about 25% of the total glaciers in the third polar region. The data covers the whole third pole area except Altai mountain, with a spatial resolution of 30m.

0 2020-04-29