As a solid reservoir, a glacier can regulate regional water resources. The annual net mass balance directly reflects the fluctuation of the glacier and climate variability. Based on 51 years of mass balance observatio...As a solid reservoir, a glacier can regulate regional water resources. The annual net mass balance directly reflects the fluctuation of the glacier and climate variability. Based on 51 years of mass balance observation data, the mass balance of Tianshan Mountains Urumqi Glacier No. 1 experienced a nine times positive balance fluctuation and nine times negative balance fluctuation. There were 35 and 16 negative and positive balance years, respectively. From 1996/97 to 2008/09, 12 consecutive negative balance years were observed at Tianshan Mountains Urumqi Glacier No. 1. These results demon- strate that the Urumqi Glacier No. 1 is experiencing a strong negative balance, and the strongest negative balance, -931 mm w.e. (mm water equivalent), during the observation period occurred in 2008. In addition, the cumulative mass balance reached 13,709 mm w.e. in 2008. However, in 2009, the mass balance was positive at 63 mm w.e. The equilibrium-line al- titude changes with the fluctuation in the mass balance, and the effective mass balance gradient is 7.4 mrn/m. In this paper, the headwaters of the Urumqi River were analyzed using meteorological data from 1958 to 2009, including the average seasonal temperature and precipitation. The results showed that the main factor associated with the mass balance variation of Glacier No. 1 is the fluctuation in the summer air temperature, followed by changes in the precipitation.展开更多
This paper is based on observed mass balance between East and West Branch of Urumqi Glacier No. l, meteorological data dur- ing 1988-2010, comparative studies the mass balance variations, and analyses the mass balance...This paper is based on observed mass balance between East and West Branch of Urumqi Glacier No. l, meteorological data dur- ing 1988-2010, comparative studies the mass balance variations, and analyses the mass balance sensitivity to climate change. Re- sults show that average mass balance of East and West Branch was -532 mm/a and 435 mm/a, cumulative mass balance was 12,227 mm (ice thinned by 13.6 m) and -10,001 mm (ice thinned by 11.1 m), respectively, and mass loss of East Branch was 97 mm/a larger than West Branch. The East and West Branch ELA (equilibrium line altitude) ascended about 176 m and 154 m, analysis shows the steady-state ELA0 was 3,942 m a.s.1, and 4,011 m a.s.1., and when East and West Branch mass balance de- creased by 100 ram, ELA ascended 20 m and 23 m, respectively. The AAR (accumulation area ratio) of East and West Branch presented an obviously decreasing trend of 34.5% and 23%, equilibrium-state AAR0 was 65% and 66%, when East and West Branch mass balance increased by 100 mm, AAR ascended 4.6% and 4.2%, respectively. Glacier mass balance was sensitive to change of net ablation, net ablation of East and West Branch increased 10x 104 m3, and mass balance decreased 110 mm and 214 mm, respectively. By analyzing mass balance sensitivity to climate change, results suggest that East and West Branch mass bal- ance decreased (increased) 463 mm and 388 mm when ablation period temperature increased (decreased) by 1 ~C, East and West Branch mass balance increased (decreased) 140 mm and 158 mm when annual precipitation increased (decreased) by 100 mm, and sensitivity of East Branch mass balance to climate change was more intense than that of West Branch.展开更多
Retrieval of oxalate from snow and ice provides information on past environmental changes. In recent years, records of organic acids in middle-and low-latitude glaciers have attracted the attention of researchers glob...Retrieval of oxalate from snow and ice provides information on past environmental changes. In recent years, records of organic acids in middle-and low-latitude glaciers have attracted the attention of researchers globally. In this study, we analyzed oxalates in an ice core from Laohugou Glacier No. 12 on the Qilian Mountains at an elevation of 5,040 m a.s.l. in2006. Average oxalate concentration was 18.5±2.4 ng/g over the prior 46 years. Oxalate values showed a significantly increasing trend since 1985. From 1985 to 1995, oxalate concentrations had large fluctuations, peaking in about 1987 and exhibiting a slightly decreasing trend since 1995. The result shows that the abrupt increase of oxalate concentration in the ice core since the mid-1980 s reflects atmospheric environmental pollution by human and industrial activities.展开更多
Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In t...Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 41001040 and J0630966)the Foundation for Excellent Youth Scholars of CAREERI (No. 51Y084911)+1 种基金the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-EW-311)the National Basic Research Program of China (2010CB951003)
文摘As a solid reservoir, a glacier can regulate regional water resources. The annual net mass balance directly reflects the fluctuation of the glacier and climate variability. Based on 51 years of mass balance observation data, the mass balance of Tianshan Mountains Urumqi Glacier No. 1 experienced a nine times positive balance fluctuation and nine times negative balance fluctuation. There were 35 and 16 negative and positive balance years, respectively. From 1996/97 to 2008/09, 12 consecutive negative balance years were observed at Tianshan Mountains Urumqi Glacier No. 1. These results demon- strate that the Urumqi Glacier No. 1 is experiencing a strong negative balance, and the strongest negative balance, -931 mm w.e. (mm water equivalent), during the observation period occurred in 2008. In addition, the cumulative mass balance reached 13,709 mm w.e. in 2008. However, in 2009, the mass balance was positive at 63 mm w.e. The equilibrium-line al- titude changes with the fluctuation in the mass balance, and the effective mass balance gradient is 7.4 mrn/m. In this paper, the headwaters of the Urumqi River were analyzed using meteorological data from 1958 to 2009, including the average seasonal temperature and precipitation. The results showed that the main factor associated with the mass balance variation of Glacier No. 1 is the fluctuation in the summer air temperature, followed by changes in the precipitation.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41001040 and J0630966)the Foundation for Excellent Youth Scholars of CAREERI (No. 51Y084911)the National Basic Research Program of China (2010CB951003)
文摘This paper is based on observed mass balance between East and West Branch of Urumqi Glacier No. l, meteorological data dur- ing 1988-2010, comparative studies the mass balance variations, and analyses the mass balance sensitivity to climate change. Re- sults show that average mass balance of East and West Branch was -532 mm/a and 435 mm/a, cumulative mass balance was 12,227 mm (ice thinned by 13.6 m) and -10,001 mm (ice thinned by 11.1 m), respectively, and mass loss of East Branch was 97 mm/a larger than West Branch. The East and West Branch ELA (equilibrium line altitude) ascended about 176 m and 154 m, analysis shows the steady-state ELA0 was 3,942 m a.s.1, and 4,011 m a.s.1., and when East and West Branch mass balance de- creased by 100 ram, ELA ascended 20 m and 23 m, respectively. The AAR (accumulation area ratio) of East and West Branch presented an obviously decreasing trend of 34.5% and 23%, equilibrium-state AAR0 was 65% and 66%, when East and West Branch mass balance increased by 100 mm, AAR ascended 4.6% and 4.2%, respectively. Glacier mass balance was sensitive to change of net ablation, net ablation of East and West Branch increased 10x 104 m3, and mass balance decreased 110 mm and 214 mm, respectively. By analyzing mass balance sensitivity to climate change, results suggest that East and West Branch mass bal- ance decreased (increased) 463 mm and 388 mm when ablation period temperature increased (decreased) by 1 ~C, East and West Branch mass balance increased (decreased) 140 mm and 158 mm when annual precipitation increased (decreased) by 100 mm, and sensitivity of East Branch mass balance to climate change was more intense than that of West Branch.
基金supported by Equipment Function Development Technology Innovation Project of Chinese Academy of Science(Y429C51005)the National Natural Science Foundation of China(41301064)+1 种基金Gansu Provincial Natural Science Foundation of China(1506RJZA286)National Found for Fostering Talents of Basic Science(Y311801001)
文摘Retrieval of oxalate from snow and ice provides information on past environmental changes. In recent years, records of organic acids in middle-and low-latitude glaciers have attracted the attention of researchers globally. In this study, we analyzed oxalates in an ice core from Laohugou Glacier No. 12 on the Qilian Mountains at an elevation of 5,040 m a.s.l. in2006. Average oxalate concentration was 18.5±2.4 ng/g over the prior 46 years. Oxalate values showed a significantly increasing trend since 1985. From 1985 to 1995, oxalate concentrations had large fluctuations, peaking in about 1987 and exhibiting a slightly decreasing trend since 1995. The result shows that the abrupt increase of oxalate concentration in the ice core since the mid-1980 s reflects atmospheric environmental pollution by human and industrial activities.
基金as part of the Department of Science and Technology (DST), Government of India sponsored research projects titled “Centre of Excellence for Glaciological Research in Western Himalaya”the financial assistance received from the Department under the projects to conduct the research。
文摘Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin.