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As the Third Pole of the Earth and the Water Tower of Asia, the Tibetan Plateau (TP) nurtures large numbers of glacial lakes, which are sensitive to global climate change. These lakes modulate the freshwater ecosystem in the region but concurrently pose severe threats to the valley population by means of sudden glacial lake outbursts and consequent floods (GLOFs). The lack of high-resolution multi-temporal inventory of glacial lakes in TP hampers a better understanding and prediction of the future trend and risk of glacial lakes. Here, we created a multi-temporal inventory of glacial lakes in TP using a 30-year record of 42,833 satellite images (1990–2019), and we discussed their characteristics and spatio-temporal evolution over the years. Results showed that their number and area had increased by 3285 and 258.82 km2 in the last 3 decades, respectively. We noticed that different regions of the TP exhibited varying change rates in glacial lake size; most regions show a trend of expansion and increase in glacial lakes, while some regions show a trend of decreasing such as the western Pamir and the eastern Hindu Kush. The mapping uncertainty is about 17.5%, which is lower than other available datasets, thus making our inventory reliable for the spatio-temporal evolution analysis of glacial lakes in the TP. Our lake inventory data are publicly published, it can help to study climate change–glacier–glacial lake–GLOF interactions in the Third Pole and serve as input to various hydro-climatic studies. [ABSTRACT FROM AUTHOR]

The surface uplift history of the Tibetan Plateau has provided a key boundary criterion for various geological, climatic, and environmental events since the Cenozoic. The paleoelevation history of the plateau is organically associated with interactions amongst deep geodynamics, earth surface processes, and climate change. Understanding of plateau uplift history has been advanced by the development of a number of paleoaltimetries and their application to studies of the Tibetan Plateau: the paleogeomorphic scenario for the Early Eocene Tibetan Plateau is thought to include two high mountains, the ca. 4500 m Gangdese Mountains to the south, and the ca. 5000 m Qiangtang Center Watershed Mountains to the north. Between these ranges, a low-elevation basin (ca. 2500 m) is thought to have been present. The Himalayas in the southern Tibetan Plateau was close to sea level at this time, while the Hoh Xil Basin in the north reached an elevation of no more than 1500 m. Thus, the so-called 'Roof of the World' Tibetan Plateau formed subsequent to the Miocene. Nevertheless,, the uplift histories of the different terranes that comprise this plateau currently remain unclear, which constrains the uplift history reconstruction of the entire Tibetan Plateau. Additional paleoelevation data from different areas, obtained using multi-paleoaltimeters, is required to resolve the forms and processes of Tibetan Plateau uplift and extension. [ABSTRACT FROM AUTHOR]

Many lakes on the Tibetan Plateau are surrounded by palaeo-shorelines that document former lake-level highstands and hence past changes in climate. Establishing accurate chronologies for these shorelines is crucial to correlate lake-level fluctuations with palaeo-environmental histories that are commonly inferred from lake sedimentary records. Here we apply surface exposure dating to constrain the age of two lake-level highstands at one of the largest Tibetan lakes – Tangra Yumco – which has well developed palaeo-shorelines located up to ∼185 m above the current lake. For sampling we focussed on wave-cut bedrock terraces that vary considerably in width, because they were carved into rocks of different erodibility. Samples from the highest strath terrace (∼180–185 m above the lake) at three different sites yield tightly clustered 10Be ages between 7.39 ± 0.19 ka and 7.87 ± 0.27 ka (internal errors), which constrain the end of an early Holocene lake-level highstand at 7.6 ± 0.6 ka (external error). The consistency of the 10Be ages indicates that bedrock erosion by wave attack reduced the inherited 10Be component to negligible amounts, because otherwise samples would show considerable age scatter. Two bedrock samples from a lower terrace (∼140–145 m above the lake) and one amalgamated clast sample from a beach ridge on the same terrace yield 10Be ages between 4.04 ± 0.14 ka and 4.50 ± 0.15 ka. These ages document that the lake level dropped by ∼40 m between ∼7.6 ka and ∼4.3 ka. Granite boulders from the two investigated terraces yield apparent 10Be ages that are ∼6 ka and ∼27 ka older than the ages of the respective terraces, indicating that this sample type is not reliable in this setting. Overall, our results demonstrate that exposure dating of bedrock terraces provides a valuable tool to reconstruct lake-level histories on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]