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The Lancang River Basin (LRB) crosses from the higher inland Tibet Plateau to lower south Asia. Glaciers in upper reaches of the basin are significant reservoirs of freshwater and are considered to contribute substantially to the runoff of the Lancang River. In this study, we present the results of glacier inventories of the LRB and demonstrate its changes during the past 40 years, based on investigations conducted during two periods: the first (1968–1975) and the second (2005–2010) glacier inventory of China. Total area of the 423 measured glaciers in the LRB decreased by 98.50 ± 26.61 km2 from 328.16 ± 20.29 km2 in 1968–1975 to 229.66 ± 16.48 km2 in 2005–2010, indicating a loss in total glacier area of about 30% ± 8% during the past 40 years (at a mean area loss rate of 0.75% ± 0.2% a-1), which is comparable to glacier changes in other regions of high Asia. Southern glaciers in the LRB have experienced greater area loss than the northern inland Tibet regions, indicating more sensitivity of temp...

Heterogeneous mass wastage has been found across the northwestern Tibet Plateau, and both slight positive and negative average mass budgets were observed using different data sets during the past decades. The north bank of the Bangong Co Basin partly covers the Western Kunlun Mountains and Karakoram Mountains. The assessment of glacier mass budget in this region over a long period is of particular interest to understanding the regional diversity of the mass changes of glaciers. Changes in glacier mass in the area of concern were assessed by differentiation of digital elevation models (DEMs) from the earliest available topographic maps, the Shuttle Radar Terrain Mission (SRTM), and the Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) stereo images. Results show that glaciers in this basin have in general experienced a decelerated mass loss but with regional differences. Glaciers were found to have lost a volume of 4.45 ± 0.63 km3 from 1968 to 2007, corresponding to -0.18 ± 0...

Due to the effect of Indian monsoon, the Kangri Karpo Mountain, located in southeast Tibetan Plateau, is the most humid region of Tibetan Plateau, and become one of the most important and concentrated regions with maritime (temperate) glaciers development. Glacier mass loss in Kangri Karpo Mountain is important contributor to global mean sea level rise, and it change runoff distribution, increase risk of glacial lake outburst floods (GLOFs). Because of their difficult accessibility and high labor costs, the knowledge of glaciological parameters of glaciers in the Kangri Karpo Mountain is still limited. This study presents glacier elevation changes in the Kangri Karpo Mountain, by utilizing geodetic methods based on digital elevation models (DEM) derived from Topographic Maps (1980), the Shuttle Radar Topography Mission (SRTM) DEM (2000), and TerraSAR-X/TanDEM-X (2014). Glacier area and length changes were derived from Topographical Maps and Landsat TM/ETM+/OLI images between 1980 and 2015. Our results show that the Kangri Karpo Mountain contains 1166 glaciers, with an area of 2048.50 ± 48.65 km2 in 2015. Ice cover in the Kangri Karpo Mountain diminished by 679.51 ± 59.49 km2 (24.9 % ± 2.2 %) or 0.71 % ± 0.06 % a-1 from 1980–2015, however, with nine glaciers in advance from 1980–2015. Glaciers with area of 788.28 km2 in the region, as derived from DEM differencing, have experienced a mean mass deficit of 0.46 ± 0.08 m w.e. a-1 from 1980–2014. These glaciers showed slight accelerated shrinkage and significant accelerated mass loss during 2000–2015 compared to that during 1980–2000, which is consistent with the tendency of climate warming.

The Tibetan Plateau interior area (TPIA), often termed the Qangtang Plateau, is distinguished by many dome-like mountains higher than 6000 ma.s.l. These mountains provide favourable conditions for the development of ice caps and glaciers of extreme continental/subpolar type. According to historical topographic maps (1959–80) and recent Landsat images (2004–11), continuous retreat was observed and the glacierized part of this area decreased by 9.5% (0.27% a–1) with respect to the total glacier area of 8036.4 km2 in the 1970s. Glaciers in the Zhari Namco basin have experienced the highest area shrinkage, with a reduction rate of 0.72% a–1, while the smallest reduction occurred in Bangong Co (0.12% a–1) and Dogai Coying basins (0.11% a–1). A regional gradient of area loss was found, with a larger decrease in the south and a smaller decrease in the north of the plateau. Comparisons indicate glaciers have experienced smaller shrinkage in the TPIA than in surrounding regions. Glacier shrinkage in the TPIA is mainly attributed to an increase in air temperature, while precipitation, glacier size and positive difference of glaciation also played an important role.

To assess changes in glacial lakes in the Chinese Himalaya, 2 inventory phases were conducted on the basis of 278 aerial survey topography maps from the 1970s and 38 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images from the 2000s. In the past 30 years, the number of glacial lakes has decreased, from 1750 to 1680 (a decrease of 4.0%), whereas the average area of glacial lakes expanded from 166.48 to 215.28 km2 (an increase of 29.7%). Between 3400 and 6000 m, glacial lake areas expanded at rates of 2–84% in almost all 100-m elevation bands, and the dominant expansion rates at different elevations were inversely correlated with glacier area retreating rates to some degree. Glacial lake expansion was a dominant contributor to the increase in glacial lake area, accounting for about 67% of the net changes in lake area, whereas newly formed lakes accounted for the remaining 33%.

Temperate glaciers are more sensitive to climate changes than polar or continental glaciers, and can drive remarkable runoff variation in local water catchments. Here we present recent glacier shrinkage and runoff change for Hailuogou glacier, a typical monsoon temperate glacier on the east slope of Mount Gongga (Minya Konga), China. The surface area of Hailuogou glacier has decreased by 3.5% (0.92 km2) between 1966 (aerial photographs) and 2007 (ASTER images). Flow measurements at a stream gauge about 500 m down-glacier commencing in 1994 display a remarkable increase in annual runoff (mostly during July–September) since 1999. Annual runoff over the same period in a nonglacierized but forested subcatchment (9.17 km2) did not experience significant change. By separating the daily rainfall component from the daily total discharge, monthly catchment water-balance series were calculated for the period 1994–2005, which shows an increasing trend of glacier storage loss. We concluded that air-temperature rise (with a trend of +0.2°C (10 a)−1between 1988 and 2005, recorded at nearby weather stations) has had an increased effect on glacier mass loss and river runoff change during the past 20 years.

Longbasaba and Pida lakes are two moraine-dammed lakes located at the headwaters of the Geiqu River, a tributary of the Pumqu River in the Chinese Himalayas, at an elevation of about 5700 m. The minimum distance between the two lakes is 24 m and their difference in elevation is about 76 m. Breach risks were assessed on the basis of field surveys carried out in the summers of 2004, 2005, and 2006. Empirical formulae for breaching of moraine dams and the BREACH model for earthen dam failure were employed to simulate the breach properties and hydrograph of floods at the breaching site of the dam from the two lakes. The modeling showed that an outburst flood from Longbasa-ba and Pida lakes would last for about 5.5 hours and have a peak discharge of about 3–5 × 104 m3/s at about 1.8 hours after the beginning of the outburst.

This chapter summarizes recent glacier variations in China as investigated using remote-sensing methods. We find that glaciers in China have lost a tremendous amount of ice mass since the Little Ice Age maximum: area and ice volume have decreased by 26.7 and 24.5 % of the respective amounts of glaciers based on maps compiled during the late 1950s and 1980s. Chinese Glaciers have been in a general state of mass loss during recent decades as monitored by satellite remote-sensing methods over glaciers totaling one fifth of the glacier area in China. At present, the ability to monitor ice volume change and the surface velocity of glaciers by satellite is relatively new, but shows potential for glaciers having complex topographical conditions in the high mountains. This is an important research focus, in part because Chinese economic development is locally heavily impacted by changes in the glacier dynamical regime due to (1) glaciers’ role in supplying meltwater to most of the region and (2) potential for local glaciological hazards.