scholarly journals Ecolosystem changes and possible mechanisms of Dagze Co in the Tibetan Plateau during the past 1000 years

2021 ◽  
Vol 33 (4) ◽  
pp. 1276-1288
Author(s):  
Li Xiumei ◽  
◽  
Hou Juzhi ◽  
Wang Mingda ◽  
Xu Lei
2018 ◽  
Vol 52 (5-6) ◽  
pp. 3599-3608 ◽  
Author(s):  
Jianping Duan ◽  
Zhuguo Ma ◽  
Naiming Yuan ◽  
Lun Li ◽  
Liang Chen

Author(s):  
Cheryl Colopy

From a remote outpost of global warming, a summons crackles over a two-way radio several times a week: . . . Kathmandu, Tsho Rolpa! Babar Mahal, Tsho Rolpa! Kathmandu, Tsho Rolpa! Babar Mahal, Tsho Rolpa! . . . In a little brick building on the lip of a frigid gray lake fifteen thousand feet above sea level, Ram Bahadur Khadka tries to rouse someone at Nepal’s Department of Hydrology and Meteorology in the Babar Mahal district of Kathmandu far below. When he finally succeeds and a voice crackles back to him, he reads off a series of measurements: lake levels, amounts of precipitation. A father and a farmer, Ram Bahadur is up here at this frigid outpost because the world is getting warmer. He and two colleagues rotate duty; usually two of them live here at any given time, in unkempt bachelor quarters near the roof of the world. Mount Everest is three valleys to the east, only about twenty miles as the crow flies. The Tibetan plateau is just over the mountains to the north. The men stay for four months at a stretch before walking down several days to reach a road and board a bus to go home and visit their families. For the past six years each has received five thousand rupees per month from the government—about $70—for his labors. The cold, murky lake some fifty yards away from the post used to be solid ice. Called Tsho Rolpa, it’s at the bottom of the Trakarding Glacier on the border between Tibet and Nepal. The Trakarding has been receding since at least 1960, leaving the lake at its foot. It’s retreating about 200 feet each year. Tsho Rolpa was once just a pond atop the glacier. Now it’s half a kilometer wide and three and a half kilometers long; upward of a hundred million cubic meters of icy water are trapped behind a heap of rock the glacier deposited as it flowed down and then retreated. The Netherlands helped Nepal carve out a trench through that heap of rock to allow some of the lake’s water to drain into the Rolwaling River.


2020 ◽  
Vol 21 (10) ◽  
Author(s):  
Jianping Duan ◽  
Lun Li ◽  
Liang Chen ◽  
Haoxin Zhang

Author(s):  
Robert A. Spicer ◽  
Tao Su ◽  
Paul J. Valdes ◽  
Alexander Farnsworth ◽  
Fei-Xiang Wu ◽  
...  

AbstractThe Tibetan Plateau was built through a succession of Gondwanan terranes colliding with Asia during the Mesozoic. These accretions produced a complex Paleogene topography of several predominantly east–west trending mountain ranges separated by deep valleys. Despite this piecemeal assembly and resultant complex relief, Tibet has traditionally been thought of as a coherent entity rising as one unit. This has led to the widely used phrase ‘the uplift of the Tibetan Plateau’, which is a false concept borne of simplistic modelling and confounds understanding the complex interactions between topography climate and biodiversity. Here, using the rich palaeontological record of the Tibetan region, we review what is known about the past topography of the Tibetan region using a combination of quantitative isotope and fossil palaeoaltimetric proxies, and present a new synthesis of the orography of Tibet throughout the Paleogene. We show why ‘the uplift of the Tibetan Plateau’ never occurred, and quantify a new pattern of topographic and landscape evolution that contributed to the development of today’s extraordinary Asian biodiversity.


2020 ◽  
Author(s):  
Kejia Ji ◽  
Erlei Zhu ◽  
Guoqiang Chu ◽  
Juzhi Hou

<p>Precise age controls are fundamental prerequisites for reconstructing past climate and environment changes. Lakes on the Tibetan Plateau are one of the important archives for studying past climate and environment changes. However, radiocarbon ages for lake sediment core are subject to old radiocarbon reservoir effects, which caused severe problems in constructing age controls for lake sediment cores, especially on the Tibetan Plateau (TP). Here we present a varve chronology over the past 2000 years at Jiang Co on the central TP. The clastic-biogenic varves comprise of a coarse-grained layer and a fine-grained layer observed by petrographic microscope and Electron Probe Micro Analyzer. Varve chronology is supported by measurements of <sup>210</sup>Pb and <sup>137</sup>Cs, which is further used to determine the radiocarbon reservoir ages in the past ~2000 years. The percentage of coarse-grain layer thickness within single varves was considered as proxy for precipitation as the coarse grains were mainly transported by runoff, which is highly correlated with local meteorological observation. During the past 2000 years, the precipitation records show centennial-scale fluctuations that are consistent with regional records. The varve chronology at Jiang Co provides a valuable opportunity to examine variation in reservoir ages on the TP and a robust chronology for reconstructing paleoclimate.</p>


2007 ◽  
Vol 46 ◽  
pp. 362-366 ◽  
Author(s):  
Tandong Yao ◽  
Keqin Duan ◽  
L.G. Thompson ◽  
Ninglian Wang ◽  
Lide Tian ◽  
...  

AbstractTemperature variation on the Tibetan Plateau over the last 1000 years has been inferred using a composite δ18O record from four ice cores. Data from a new ice core recovered from the Puruogangri ice field in the central Tibetan Plateau are combined with those from three other cores (Dunde, Guliya and Dasuopu) recovered previously. The ice-core δ18O composite record indicates that the temperature change on the whole Tibetan Plateau is similar to that in the Northern Hemisphere on multi-decadal timescales except that there is no decreasing trend from AD 1000 to the late 19th century. The δ18O composite record from the northern Tibetan Plateau, however, indicates a cooling trend from AD 1000 to the late 19th century, which is more consistent with the Northern Hemisphere temperature reconstruction. The δ18O composite record reveals the existence of the Medieval Warm Period and the Little Ice Age (LIA) on the Tibetan Plateau. However, on the Tibetan Plateau the LIA is not the coldest period during the last millennium as in other regions in the Northern Hemisphere. The present study indicates that the 20th-century warming on the Tibetan Plateau is abrupt, and is warmer than at any time during the past 1000 years.


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