A tree-ring based precipitation reconstruction for the Baluntai region on the southern slope of the central Tien Shan Mountains, China, since A.D. 1464

Abstract A preliminary study of a point-by-point spatial precipitation reconstruction for northwestern (NW) China is explored, based on a tree-ring network of 132 chronologies. Precipitation variations during the past ~200–400 yr (the common reconstruction period is from 1802 to 1990) are reconstructed for 26 stations in NW China from a nationwide 160-station dataset. The authors introduce a “search spatial correlation contour” method to locate candidate tree-ring predictors for the reconstruction data of a given climate station. Calibration and verification results indicate that most precipitation reconstruction models are acceptable, except for a few reconstructions (stations Hetian, Hami, Jiuquan, and Wuwei) with degraded quality. Additionally, the authors compare four spatial precipitation factors in the instrumental records and reconstructions derived from a rotated principal component analysis (RPCA). The northern and southern Xinjiang factors from the instrumental and reconstructed data agree well with each other. However, differences in spatial patterns between the instrumentation and reconstruction data are also found for the other two factors, which probably result from the relatively poor quality of a few stations. Major drought events documented in previous studies—for example, from the 1920s through the 1930s for the eastern part of NW China—are reconstructed in this study.

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Measuring and inferring the ice thickness distribution of four glaciers in the Tien Shan, Kyrgyzstan

Journal of Glaciology ◽

10.1017/jog.2020.104 ◽

2020 ◽

pp. 1-18

Author(s):

Lander Van Tricht ◽

Philippe Huybrechts ◽

Jonas Van Breedam ◽

Johannes J. Fürst ◽

Oleg Rybak ◽

...

Keyword(s):

Cross Validation ◽

Thickness Distribution ◽

Tien Shan ◽

Ice Thickness ◽

Ice Volume ◽

In Situ Data ◽

Radio Echo Sounding ◽

Thickness Measurements ◽

Tien Shan Mountains

Abstract Glaciers in the Tien Shan mountains contribute considerably to the fresh water used for irrigation, households and energy supply in the dry lowland areas of Kyrgyzstan and its neighbouring countries. To date, reconstructions of the current ice volume and ice thickness distribution remain scarce, and accurate data are largely lacking at the local scale. Here, we present a detailed ice thickness distribution of Ashu-Tor, Bordu, Golubin and Kara-Batkak glaciers derived from radio-echo sounding measurements and modelling. All the ice thickness measurements are used to calibrate three individual models to estimate the ice thickness in inaccessible areas. A cross-validation between modelled and measured ice thickness for a subset of the data is performed to attribute a weight to every model and to assemble a final composite ice thickness distribution for every glacier. Results reveal the thickest ice on Ashu-Tor glacier with values up to 201 ± 12 m. The ice thickness measurements and distributions are also compared with estimates composed without the use of in situ data. These estimates approach the total ice volume well, but local ice thicknesses vary substantially.

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An outline of avalanches in the Tien Shan mountains

Annals of Glaciology ◽

10.3189/1992aog16-1-7-10 ◽

1992 ◽

Vol 16 ◽

pp. 7-10 ◽

Cited By ~ 1

Author(s):

Hu Ruji ◽

Ma Hong ◽

Wang Guo

Keyword(s):

Snow Cover ◽

Basal Layer ◽

Liquid Water Content ◽

Snow Accumulation ◽

Tien Shan ◽

Large Temperature ◽

Snow Avalanches ◽

Climatic Variations ◽

Tien Shan Mountains ◽

Seasonal Snow Cover

The seasonal snow cover in the Tien Shan mountains is characterized by low density, low liquid-water content and low temperature. It is known as typical dry snow. Large temperature gradients in the basal layer of the snow cover exist throughout the entire period of snow accumulation, and depth hoar is therefore extremely well-developed. Full-depth depth-hoar avalanches, however, seldom occur. Avalanches in the Tien Shan mountains are mostly loose snow avalanches. Although normally not large in size, they are the most dangerous type. The occurrence of hazardous avalanches shows cycles of about ten years because of periodic climatic variations.

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Permafrost warming in the Tien Shan Mountains, Central Asia

Global and Planetary Change ◽

10.1016/j.gloplacha.2006.07.023 ◽

2007 ◽

Vol 56 (3-4) ◽

pp. 311-327 ◽

Cited By ~ 80

Author(s):

S.S. Marchenko ◽

A.P. Gorbunov ◽

V.E. Romanovsky

Keyword(s):

Central Asia ◽

Tien Shan ◽

Permafrost Warming ◽

Tien Shan Mountains

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A 406-year non-growing-season precipitation reconstruction in the southeastern Tibetan Plateau

Climate of the Past ◽

10.5194/cp-17-2381-2021 ◽

2021 ◽

Vol 17 (6) ◽

pp. 2381-2392

Author(s):

Maierdang Keyimu ◽

Zongshan Li ◽

Bojie Fu ◽

Guohua Liu ◽

Fanjiang Zeng ◽

...

Keyword(s):

Tibetan Plateau ◽

Tree Ring ◽

Tree Growth ◽

Ring Width ◽

Growing Season ◽

Climatic Conditions ◽

Forest Growth ◽

Drought Severity ◽

Precipitation Reconstruction ◽

Southeastern Tibetan Plateau

Abstract. Trees record climatic conditions during their growth, and tree rings serve as proxy to reveal the features of the historical climate of a region. In this study, we collected tree-ring cores of hemlock forest (Tsuga forrestii) from the northwestern Yunnan area of the southeastern Tibetan Plateau (SETP) and created a residual tree-ring width (TRW) chronology. An analysis of the relationship between tree growth and climate revealed that precipitation during the non-growing season (NGS) (from November of the previous year to February of the current year) was the most important constraining factor on the radial tree growth of hemlock forests in this region. In addition, the influence of NGS precipitation on radial tree growth was relatively uniform over time (1956–2005). Accordingly, we reconstructed the NGS precipitation over the period spanning from 1600–2005. The reconstruction accounted for 28.5 % of the actual variance during the common period of 1956–2005. Based on the reconstruction, NGS was extremely dry during the years 1656, 1694, 1703, 1736, 1897, 1907, 1943, 1982 and 1999. In contrast, the NGS was extremely wet during the years 1627, 1638, 1654, 1832, 1834–1835 and 1992. Similar variations of the NGS precipitation reconstruction series and Palmer Drought Severity Index (PDSI) reconstructions of early growing season from surrounding regions indicated the reliability of the present reconstruction. A comparison of the reconstruction with Climate Research Unit (CRU) gridded data revealed that our reconstruction was representative of the NGS precipitation variability of a large region in the SETP. Our study provides the first historical NGS precipitation reconstruction in the SETP which enriches the understanding of the long-term climate variability of this region. The NGS precipitation showed slightly increasing trend during the last decade which might accelerate regional hemlock forest growth.

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