To obtain full coverage, we interpolated these voids using nearest neighbour interpolation. Based on the observations of 138 glaciers, a similar rate of area loss was estimated for the time periods, 19942006 and 20062020 (0.140.27 and 0.160.19%a1). km) respectively. Dokriani, Satopanth, Bhagirath Kharak, Gangotri, Dunagiri, Tipra and Chorabari are the major glaciers in Garhwal Himalaya undergone field-based mass balance studies prominently (Dobhal et al., 2008, 2013). A typical hanging glacier in Central Himalayas For the 138 glaciers measured in 1994, 2006 and 2020, the debris cover increased from 65.12.3km2 (21.0%) in 1994 to 67.51.9 (21.8%) in 2006 to 73.31.8km2 (24.7%) in 2020. T B provided guidance to improve the quality of work. For numbering see Figure 1. Glacier size, debris-cover extent, elevation range and aspect are found controlling glacier-specific factors for the fractional rate of area loss in UAB from 1994 to 2020. These glaciers are separated by a linear ridge (Balakun) which terminates abruptly on the eastern prox imity. However, the area of the large glaciers (>10km2) is much more broadly distributed in the elevation range 47005800m a.s.l., consistent with debris-covered glaciers which tend to have long narrow tongues. To understand the basin scale area loss, we need to understand the area loss rates of individual glaciers as a function of their attributes since glaciers respond heterogeneously even under similar climatic conditions (Salerno and others, Reference Salerno2017; Brun and others, Reference Brun, Wagnon, Berthier, Jomelli, Maharjan, Shrestha and Kraaijenbrink2019). topographic map glacier fronts with independent measure-ments whenever they are available. The earlier study in UAB observed the similar (0.46%a1) rate of increase of the debris cover during 19682006 (Bhambri and others, Reference Bhambri, Bolch, Chaujar and Kulshreshtha2011a). However, we note that after ~20002010, the CRU data show a sharp increase in precipitation. Scatter plots showing the correlation between area loss (%) during the study period (19942020) and non-climatic parameters; (a) glacier area, (b) debris cover %, (c) elevation range, (d) area loss vs aspect. More than 60% of surface areas of the Satopanth and Bhagirath Kharak glaciers are also thickly debris-covered and retreating at the rate of 9.7 and 7 m a 1, respectively (Nainwal et al. Long-term high altitude in-situ meteorological records in the basin along with ground-based glaciological measurements (e.g. Comparison of area loss (% a1) and debris cover change (% a1) with previous studies in the Himalaya. which is significantly higher than the glaciers (i.e. Fig. In this paper, we describe our attempt to perform this task for two important glaciers in the Indian Himalaya: Satopanth (SPG) and Bhagirath Kharak (BKG) Glaciers. 1) is located at an elevation of ~5040m a.s.l. Fig. Nainwal and others (Reference Nainwal, Banerjee, Shankar, Semwal and Sharma2016) have extended this analysis to the period 19372013 and reported retreat rates to be 5.7 and 6.0ma1 for Satopanth and Bhagirath Kharak glaciers respectively, corresponding to the area loss of 0.27 and 0.17km2. From the eastern slopes of Badrinath and Chaukhamba peaks it rise the altitude of the glacier is 3,820 m. and from the glacier Alaknanada River is also rises and cross the Bhagirath Kharak. The debris-cover area expands up glacier over the time and slowdown the glacier melting (Dobhal and others, Reference Dobhal, Mehta and Srivastava2013; Pratap and others, Reference Pratap, Dobhal, Mehta and Bhambri2015; Shah and others, Reference Shah, Banerjee, Nainwal and Shankar2019), however such glaciers lose mass mainly by thinning not retreat (Banerjee and Shankar, Reference Banerjee and Shankar2013; Ragettli and others, Reference Ragettli, Bolch and Pellicciotti2016; Remya and others, Reference Remya, Kulkarni, Hassan and Nainwal2020). A comparison with previous studies in UAB indicates consistent area loss of ~0.15% a1 since the 1960s. September and October) with minimum seasonal snow and cloud cover were selected. The above discussion motivated us to attempt to interpret the overall changes in the glacier lengths and areas that we observe based on the following regional climate scenario: (a) the regional temperature and precipitation started showing significant positive trends after ~196080, (b) the regional temperature increased rapidly in the past three decades or so at a rate of 34C per century, and (c) the regional precipitation decreased from ~1960 to 2010 and then rapidly increased till 2020. 5. 1). Distribution of number of glaciers, total glacierised area and mean slope for each area range and morphological type. 20012), 2002 and 2008 (i.e. These regions have different climatic and topographic settings. Thus, the rate during 20062020 was significantly larger than 19942006. For Khuliya Garvya Glacier, Garg and others (Reference Garg, Shukla and Jasrotia2017) reported a retreat rate of 26.92.5ma1 during 19942015; whereas our estimate is 18.91.8ma1 during 19942020. S3b). The increasing rate of debris-cover extent over the glaciers is common for shrinking glaciers (Benn and others, Reference Benn2012; Bolch and others, Reference Bolch2012; Kirkbride and Deline, Reference Kirkbride and Deline2013) due to avalanching activity in upper reaches of glacier catchment (Scherler and others, Reference Scherler, Bookhagen and Strecker2011; Laha and others, Reference Laha2017) and the up-glacier shift of SLA (Shukla and Garg, Reference Shukla and Garg2020). Glacier area loss in UAB is dependent on glacier size and we found a significant negative correlation (r=0.73) with coefficient of determination (R 2) of 0.53 between area loss (%) and glacier area (size) (Fig. The glacier-boundaries from the different years were superimposed over each other. However, there may be exceptional regions in the western Himalaya where it may be significantly higher. UAB is a part of the Alaknanda Basin classified by the Geological Survey of India (GSI) as a third-order basin (5O 132) of Ganga River. The E-W trending Satopanth (21.17 sq. Almost all Himalayan glaciers are retreating, including Gangotri, Satopanth and Bhagirath-Kharak. As expected, the rate of area loss strongly correlates with the aspect as found elsewhere (e.g. Bhambri and others (Reference Bhambri, Bolch, Chaujar and Kulshreshtha2011a) report ~25% of the glacierised area being debris-covered. The distinction between snow patches and small glaciers (<0.5km2) is crucial, since snow can accumulate for few years on mountain slopes and ridges. Ambient equivalent black carbon (BC) measurements spanning from June to October have been carried out over an adjoining location of Satopanth and Bhagirath-Kharak Glaciers (3858m, amsl) of Central Himalaya during the year 2019. Morphological factors controlling changes in the mass balance, surface area, terminus position, and snow line altitude of Himalayan glaciers. This award was established in 2010 to honor the outstanding work of Dr. Bhagirath Singh, inaugural Scientific Director of the CIHR Institute of Infection and Immunity (III). It is also consistent with the reported rates of Mehta and others (Reference Mehta, Dobhal and Bisht2011): 13.4ma1 during 19622002 and 21.3ma1 during 20022008. There are two prominent peaks of debris-covered extents at an elevation of 4350 and 5100m a.s.l. 1): grid 01 (30.75N, 79.25E) and grid 02 (30.75N, 79.5E). We feel that more detailed work needs to be done on this issue. While the mean value of the area loss has slightly increased in the period 20062020 as compared to 19942006, no significant trend can be inferred. Nainwal and others (2016) have extended this analysis to the period 1937- 2013 and reported retreat rates to be 5.7 and 6.0ma1 for Rate of Satopanth glacier recession was higher than Bhagirath Kharak glacier. Details of the satellite data and digital elevation model (DEM) used in this study. Modern technology makes the planning of such trips so simple. A study of the Satopanth glacier in order to model the melting of debris . The supplementary material for this article can be found at https://doi.org/10.1017/jog.2022.87. The retreat rate of individual glaciers varied considerably between 4.61.8ma1 (Arwa 01 Glacier) and 18.91.8ma1 (Khuliya Garvya Glacier) (Fig. 1. For the estimation of glacier retreat, parallel lines were drawn on either side of the central flow-line (or along the maximum glacier length) at 50m intervals (Supplementary Fig. a1) is dominated by avalanches (Laha and others, Reference Laha2017). We find that . 4). We hope that our data analysis results will motivate modellers to develop physically based models which will eventually result in reliable future projections at a basin scale. 6. DeBeer and Sharp, Reference DeBeer and Sharp2009) (Fig. The comparative analysis of glacier area changes of UAB with other Himalayan basins has been done on the basis of time window and used satellite data; and indicates that the glaciers in UAB have shrunk at rates analogous to those of the other studies. Fig. retreat of the Bhagirath Kharak glacier from 2005 to 2006 was 1.5 m only, whereas the glacier retreated 319.34 m, with an average rate of 7.42 m/yr from 1962 to 2005 (Ta 10. The summer precipitation contributed ~75% to the total annual precipitation. The common points were distributed throughout the study area with the highest concentration around the glacierised regions. We could achieve a root mean square error (RMSE) less than the pixel size of the images, i.e. The RGI 6.0, ICIMOD and GGI2 inventories were derived from Landsat images acquired between 1999 and 2003 (i.e. located a little south of the basin. S2). It is located between the latitude and longitude of 30.531N and 79.2579.72E respectively. The 2020 inventory of the study area comprises 198 glaciers of different sizes, morphological types and extents of debris cover (Tables 2 and 3; Fig. Bolch and others, Reference Bolch2010a; Frey and others, Reference Frey, Paul and Strozzi2012). The numbers (120) indicate glaciers with length change estimations. Similar trends were noticed in the previous studies in Himalaya indicating sensitivity of smaller glaciers to climate change (Kulkarni and others, Reference Kulkarni, Bahuguna, Rathore, Singh, Randhawa, Sood and Dhar2007; Bolch and others, Reference Bolch2012; Chand and Sharma, Reference Chand and Sharma2015). 2) were mapped by a DGPS survey, having horizontal accuracy of 10cm. The distribution of glaciers of UAB: (a) based on their size and (b) based on their morphology. The SLA of large glaciers (>10km2) is located at a slightly lower elevation (5352m a.s.l.) Ambient equivalent black carbon (BC) measurements spanning from June to October have been carried out over an adjoining location of Satopanth and Bhagirath-Kharak Glaciers (3858m, amsl) of Central Himalaya during the year 2019. The SWIR bands of ASTER (band-4) and Sentinel (band-12) images have lower spatial resolutions of 30 and 20m respectively, and were therefore resampled in ERDAS Imagine 2014 to 15 and 10m, respectively, to match the resolution of the visible and NIR bands of the ASTER and Sentinel-2A images. The relative area loss (%) has been grouped in six classes (<5; 510; 1015; 1520; 2025 and >25) and geographical distribution (Fig. The ice loss has clearly increased after 2000 which can mainly be attributed to the current phase of accelerated atmospheric warming in the region (Sakai and Fujita, Reference Sakai and Fujita2017; Bolch and others, Reference Bolch, Wester, Mishra, Mukherji and Shrestha2019; King and others, Reference King, Bhattacharya, Bhambri and Bolch2019; Maurer and others, Reference Maurer, Schaefer, Rupper and Corley2019; Bhattacharya and others, Reference Bhattacharya2021). Disentangling the two effects requires a basin scale model of the glacier dynamics which we do not attempt. 2). Remote-sensing and field-based measurements indicate that the glacier changes are variable throughout the Himalaya (Scherler and others, Reference Scherler, Bookhagen and Strecker2011; Kulkarni and Karyakarte, Reference Kulkarni and Karyakarte2014; Azam and others, Reference Azam2018). Hostname: page-component-7ff947fb49-j6tc7 The numbers (120) indicate glaciers with length change estimations. Render date: 2023-06-30T22:58:05.882Z However, the rate was significantly larger (1.3%a1) for the period between 1990 and 2006. Consequently, two neighbouring basins that experience a similar regional climate could respond quite differently to climate forcing due to differences in the topographic settings (Garg and others, Reference Garg, Shukla and Jasrotia2017). The same is true for the length changes. This DEM was in particular generated based on high-resolution WorldView images acquired during 2013 and 2016 and has a spatial resolution of 8m. We used the HMA DEM due to its better spatial resolution as compared to the SRTM DEM and ASTER GDEM for the best temporal fit to the Sentinel-2 data. The debris is mainly composed of kyanite-sillimanite schist, gneisses and leucogranites which belong to the Pandukeshwar and Pindari Formations (Valdiya and others, Reference Valdiya, Paul, Chandra, Bhakuni and Upadhyay1999). This paper presents the results obtained from the analysis from HCN and RS supervised the research work. The debris-covered area is broadly distributed between 3800 and 5850m a.s.l. We shall see the course of River Alaknanda, Dhauliganga, Nandakini, Pindar, Mandakini, Dhauliganga. a1 19622000. We do this to contribute to the understanding of the complex processes of the dynamics of the collection of glaciers in the UAB in a rapidly changing climate. The study area is located within two 0.5 degree grids (Fig. In terms of the glacier morphology, mountain glaciers experienced the highest area losses (10.6%), followed by hanging glaciers (~9.2%) and cirque glaciers (~8.6%) (Supplementary Table S2). The rate of change of the fraction of debris cover area in UAB was significantly higher (0.61%a1) in the period 2006 and 2020 as compared to 0.31%a1 from 1994 to 2006. We also observed that average retreat rate of the large UAB glaciers increased from 9.31.9ma1 (19942006) to 13.31.8ma1 (20062020). Notice a clear slowdown in SIV during 1993/94-2015/16. The Alaknanda River originates from the ~13km long and ~750m wide Satopanth Glacier (snout ~3880 meter above sea level [m a.s.l.]). We used different multi-temporal remote-sensing data 19942020 for glacier mapping detailed in Table 1. Therefore, these two parameters are related to each other. near steep slopes or cast shadows. Location map of the study area showing clean and debris-covered parts of the glaciers and main localities. 3). 19942006 and 20062020). Valley glaciers have well-defined accumulation and ablation areas and their form is controlled by the respective topography. However, the exponent for the area is ~0.6 whereas for the elevation range it is ~1. Hence, it is difficult to identify the outlines correctly without local knowledge. The basin covers an area of ~1500km2 and ranges from ~1450m (Vishnuprayag) to 7756m a.s.l. Both the moving streams of ice are fed by the snow from Chaukhamba peaks . The updated inventory contains 198 glaciers and shows that the total glacierised area was 354.68.5km2 in 2020. Schmidt, Susanne In total, 175 glaciers could be investigated for the period 19942020. Field measurements on the Satopanth glacier (Shah and others, Reference Shah, Banerjee, Nainwal and Shankar2019) indicate that while the debris thickness decreases with elevation, there is a large spatial variation. 1b). The total number of glaciers in our inventory (198) is smaller than the RGI (223), ICIMOD (338) and GGI2 (318) inventories but larger than the GSI (159) (Supplementary Table S4). (Fig. Himalayan glaciers have been shrinking and losing mass rapidly since 1970s with an enhanced rate after 2000. Glaciological (field-based), geodetic and accumulation area ratio (AAR) are the different methods to estimate glacier mass balance. A significant increase in debris-covered area (13.44.4%) was observed during the study period. To calculate the glacier area-changes, the glacier-boundaries demarcated in the base image, 2020 were superimposed over the previous glacier-boundaries (cf. Fig. SB/DGH-101/2015 and DST/CCP/NHC/158/2018), IMSc, Chennai and SAC-ISRO funded projects. We identified 198 glaciers, comprising an area of 354.6 8.5 km2, and classified them according to their size and morphology. To estimate the area uncertainties of all glaciers, the buffer method was used with buffer sizes of half of the pixel size or co-registration error between two images. Those time periods are used to label time periods in the text and tables for sake of simplicity, although the actual image acquisition dates used in the study slightly differs for one glacier (i.e. The main discrepancy in the total number of glaciers comes from the number of small glaciers (<0.5km2). The average glacier retreat rates increased by ~30% from 9.31.9ma1 (19942006) to 13.31.8ma1 during the last decade (20062020). Western, Central and Eastern regions). Table 2. Total loading time: 0 These previous studies, however, do not assess the characteristics of the individual glaciers in the basin. Satellite images of the ablation period (i.e. The retreat of the Bhagirath Kharak glacier from 2005 to 2006 was 1.5 m only, whereas the glacier retreated 319.34 m, with an average rate of 7.42 m/yr from 1962 to 2005 (Ta- ble 2). This resulted in an average mapping uncertainty of 3.5% for TM, 2.75% for ASTER and 2.3% for Sentinel-2. The distribution of the area loss of 175 glaciers in the basin during the period 19942020. The aspect was calculated on the basis of the orientation of the centre-lines. Badrinath Dham. The inventory of GSI was prepared on 1 : 50000 scale, using survey of India (SOI) topographic maps (1962). Debris-covered glaciers have lost 2.92.6% of their area compared to the 10.82.8% loss of the debris-free ones. [1] To summarise, the average response of individual glaciers as a function of their non-climatic attributes is typically non-linear. Glaciers have an average width of 750 850 meters. In fact only 65 of the 198 glaciers had debris cover in 2020. Such small glaciers have short response time and usually adjust their geometry instantly (Huss and Fischer, Reference Huss and Fischer2016). The uncertainties of the glacier boundaries were estimated in two ways: (a) by comparing the glacier outlines from the satellite image (2020) to a field survey done during the same period at Satopanth and Bhagirath Kharak glaciers, and (b) using the buffer method (Granshaw and Fountain, Reference Granshaw and Fountain2006; Bolch and others, Reference Bolch2010a; Chand and Sharma, Reference Chand and Sharma2015). The presence of dead ice mounds creates another difficulty in delineation of debris-covered glaciers because of their close vicinity to the glacier fronts. The field debris thickness of SPG (2015-2017) is compared with the elevation change (2000-2017). We have compiled and analysed available records and data on the shrinkage of Satopanth (SPG) and Bhagirath Kharak (BKG) Glaciers, Uttarakhand, India, during the period 1936-2013. Similar behaviour has been reported in the previous studies in Alaknanda Basin (Nainwal and others, Reference Nainwal, Negi, Chaudhary, Sajwan and Gaurav2008; Bhambri and others, Reference Bhambri, Bolch, Chaujar and Kulshreshtha2011a). A modelling study on Satopanth Glacier to quantify the avalanche contribution in glacier mass balance shows that ~90% of the total glacier mass gain (~1.8m w.e. Fig. Such glaciers are defined as cirque glaciers, hanging glaciers and mountain glaciers (Fig. This is, hence, in line with our observations. Chand, Pritam These results are the same as what we observed in the UAB. www.visituttrakhand.com However, the rate of area loss of Panpatiya Glacier, reported by them, is significantly larger (0.080.03%a1) than what we have observed (0.040.13%a1). Consequently, it takes time for precipitation changes to reflect in length changes. But due . For two of the 18 glaciers, the retreat rate increased during 20062020 as compared with that of 19942006. (a) Area-elevation distribution of all glaciers (blue) and of the glaciers in different size ranges (other colours). The ablation of Bhagirath Kharak Glacier is surrounded by a thick layer of debris and above sea level their snouts are located at 3796m and 3858m. Therefore, area changes were mainly in the vicinity of the fronts (Fig. From Bhagirath Kharak Glacier originates the Alaknanda River and joins Uttar Ganga upstream to Alkapuri. Based on simple models validated with limited field data, the ice volume of the basin has been estimated to be 26.4km3 for the year 2016 (Mishra and others, Reference Mishra, Nainwal, Dobhal and Shankar2021). Geological Survey of India: Special Publication no 43, Glacier-surface velocity derived ice volume and retreat assessment in the Dhauliganga basin, central Himalaya a remote sensing and modeling based approach, Spatially variable response of Himalayan glaciers to climate change affected by debris cover, Changes of high altitude glaciers from 1969 to 2010 in the Trans-Himalayan Kang Yatze Massif, Ladakh, northwest India, Estimation of the total sub-debris ablation from point-scale ablation data on a debris-covered glacier, High Mountain Asia 8-Meter DEM Mosaics Derived from Optical Imagery, Version 1, NASA National Snow and Ice Data Center Distributed Active Archive Center, Climate change in Nepal and its impact on Himalayan glaciers, Spatio-temporal trends in the surface ice velocities of the central Himalayan glaciers, India, Temporal inventory of glaciers in the Suru sub-basin, western Himalaya: impacts of regional climate variability, Differential response of glaciers with varying debris cover extent: evidence from changing glacier parameters, On rising temperature trends at Dehradun in Doon valley of Uttarakhand, India, Tracing glacier changes since the 1960s on the south slope of Mt. Chudley and others (Reference Chudley, Miles and Willis2017) reported a loss of 45.3km2 (12.8% or 0.52%a1) in Ladakh range during 1991 and 2014. The Climate Research Unit (CRU) TS 4.04 data for the study area shows mean monthly temperatures varying from ~7C in January to ~11C in July during 19012019 (Fig. Glacier lengths were calculated from manually drawn centre-lines. km) are approximately 13 and 18.5 km long glaciers with an average width of 750 to 850 m (Figure 1 a). The Sentinel-2A image of 8 October 2020 was used as a reference image as it had most suitable conditions and matched best with our field-based differential GPS (DGPS) mapping over the frontal parts of Satopanth and Bhagirath Kharak glaciers conducted 67 October 2020 (Fig. 2) helped us to delineate glacier boundaries especially near the glacier fronts. Nainwal and others (Reference Nainwal, Negi, Chaudhary, Sajwan and Gaurav2008) have estimated the length and area changes for Satopanth glacier to be 22.8ma1 and 0.314km2 and for Bhagirath Kharak glacier to be 7.42ma1 and 0.13km2 between 1962 and 2005. The rate of area vacated in the frontal region of these two glaciers during the period 19802013 was estimated to be 0.00480.001 and 0.00270.001km2a1 respectively (Nainwal and others, Reference Nainwal, Banerjee, Shankar, Semwal and Sharma2016). During winters, from 5,288 to 7,068 meters the towering peaks raging are snow clad. Surface elevation changes of glaciers of UAB have been recently reported from 2000 to 2014 (Bandyopadhyay and others, Reference Bandyopadhyay, Singh and Kulkarni2019) and for the period 20002017 by Remya and others (Reference Remya, Kulkarni, Hassan and Nainwal2020). Further, a rate of warming of 0.026Ca1 was observed during 19702019. The total glacierised area is 354.68.1km2, of which ~27% is covered with debris. The difference between the surveyed DGPS points and the manually mapped boundaries over two glaciers was ~5m at the front ice cliff regions and ~812m at the debris-covered parts (Fig. Our analysis seems to show that this may not be adequate. For example, the snout of Balabala Glacier (No-12 in Fig. All the glaciers of UAB show a loss of area between 1994 and 2020.
Rio Dell School District Website,
Camp Victory Fireworks,
Black Panther Cia Agent Actor,
Aerotek California Jobs,
Articles B