Snow cover phenology affects alpine vegetation growth dynamics on the Tibetan Plateau: Satellite observed evidence, impacts of different biomes, and climate drivers

Changes in snow cover over the Tibetan Plateau (TP) have a significant impact on agriculture, hydrology, and ecological environment of surrounding areas. This study investigates the spatio-temporal pattern of snow depth (SD) and snow cover days (SCD), as well as the impact of temperature and precipitation on snow cover over TP from 1979 to 2018 by using the ERA5 reanalysis dataset, and uses the Mann–Kendall test for significance. The results indicate that (1) the average annual SD and SCD in the southern and western edge areas of TP are relatively high, reaching 10 cm and 120 d or more, respectively. (2) In the past 40 years, SD (s = 0.04 cm decade−1, p = 0.81) and SCD (s = −2.3 d decade−1, p = 0.10) over TP did not change significantly. (3) The positive feedback effect of precipitation is the main factor affecting SD, while the negative feedback effect of temperature is the main factor affecting SCD. This study improves the understanding of snow cover change and is conducive to the further study of climate change on TP.

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Elevational Movement of Vegetation Greenness on the Tibetan Plateau: Evidence from the Landsat Satellite Observations during the Last Three Decades

Atmosphere ◽

10.3390/atmos12020161 ◽

2021 ◽

Vol 12 (2) ◽

pp. 161

Author(s):

Liheng Lu ◽

Xiaoqian Shen ◽

Ruyin Cao

Keyword(s):

Tibetan Plateau ◽

Spatial Resolution ◽

Climate Warming ◽

Vertical Movement ◽

The Tibetan Plateau ◽

Upward Movement ◽

Vegetation Growth ◽

Vegetation Greenness ◽

Mountainous Regions ◽

Vegetation Activities

The Tibetan Plateau, the highest plateau in the world, has experienced strong climate warming during the last few decades. The greater increase of temperature at higher elevations may have strong impacts on the vertical movement of vegetation activities on the plateau. Although satellite-based observations have explored this issue, these observations were normally provided by the coarse satellite data with a spatial resolution of more than hundreds of meters (e.g., GIMMS and MODIS), which could lead to serious mixed-pixel effects in the analyses. In this study, we employed the medium-spatial-resolution Landsat NDVI data (30 m) during 1990–2019 and investigated the relationship between temperature and the elevation-dependent vegetation changes in six mountainous regions on the Tibetan Plateau. Particularly, we focused on the elevational movement of the vegetation greenness isoline to clarify whether the vegetation greenness isoline moves upward during the past three decades because of climate warming. Results show that vegetation greening occurred in all six mountainous regions during the last three decades. Increasing temperatures caused the upward movement of greenness isoline at the middle and high elevations (>4000 m) but led to the downward movement at lower elevations for the six mountainous regions except for Nyainqentanglha. Furthermore, the temperature sensitivity of greenness isoline movement changes from the positive value to negative value by decreasing elevations, suggesting that vegetation growth on the plateau is strongly regulated by other factors such as water availability. As a result, the greenness isoline showed upward movement with the increase of temperature for about 59% pixels. Moreover, the greenness isoline movement increased with the slope angles over the six mountainous regions, suggesting the influence of terrain effects on the vegetation activities. Our analyses improve understandings of the diverse response of elevation-dependent vegetation activities on the Tibetan Plateau.

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Linking deeply-sourced volatile emissions to plateau growth dynamics in southeastern Tibetan Plateau

Nature Communications ◽

10.1038/s41467-021-24415-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Maoliang Zhang ◽

Zhengfu Guo ◽

Sheng Xu ◽

Peter H. Barry ◽

Yuji Sano ◽

...

Keyword(s):

Tibetan Plateau ◽

Growth Dynamics ◽

High Elevation ◽

Fault System ◽

The Tibetan Plateau ◽

Southeastern Tibetan Plateau ◽

Surface Uplift ◽

Multi Stage ◽

Geodynamic Processes ◽

Underlying Mechanisms

AbstractThe episodic growth of high-elevation orogenic plateaux is controlled by a series of geodynamic processes. However, determining the underlying mechanisms that drive plateau growth dynamics over geological history and constraining the depths at which growth originates, remains challenging. Here we present He-CO2-N2 systematics of hydrothermal fluids that reveal the existence of a lithospheric-scale fault system in the southeastern Tibetan Plateau, whereby multi-stage plateau growth occurred in the geological past and continues to the present. He isotopes provide unambiguous evidence for the involvement of mantle-scale dynamics in lateral expansion and localized surface uplift of the Tibetan Plateau. The excellent correlation between 3He/4He values and strain rates, along the strike of Indian indentation into Asia, suggests non-uniform distribution of stresses between the plateau boundary and interior, which modulate southeastward growth of the Tibetan Plateau within the context of India-Asia convergence. Our results demonstrate that deeply-sourced volatile geochemistry can be used to constrain deep dynamic processes involved in orogenic plateau growth.

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Assessment of MODIS-Based Fractional Snow Cover Products Over the Tibetan Plateau

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing ◽

10.1109/jstars.2018.2879666 ◽

2019 ◽

Vol 12 (2) ◽

pp. 533-548 ◽

Cited By ~ 8

Author(s):

Shirui Hao ◽

Lingmei Jiang ◽

Jiancheng Shi ◽

Gongxue Wang ◽

Xiaojing Liu

Keyword(s):

Tibetan Plateau ◽

Snow Cover ◽

The Tibetan Plateau ◽

Fractional Snow Cover

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Review of "Evaluation of snow depth and snow-cover over the Tibetan Plateau in global reanalyses using in-situ and satellite remote sensing observations"

10.5194/tc-2019-49-rc1 ◽

2019 ◽

Author(s):

Anonymous

Keyword(s):

Remote Sensing ◽

Tibetan Plateau ◽

Snow Cover ◽

Snow Depth ◽

Satellite Remote Sensing ◽

The Tibetan Plateau

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IMPACT OF TIBETAN PLATEAU SNOW COVER ON ABRUPT INTERDECADAL PRECIPITATION CHANGE OVER THE INDOCHINA PENINSULA IN THE MID-1990S

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w9-57-2019 ◽

2019 ◽

Vol XLII-3/W9 ◽

pp. 57-62

Author(s):

Y. Ha ◽

Y. M. Zhu ◽

Y. J. Hu ◽

Z. Zhong

Keyword(s):

Tibetan Plateau ◽

Snow Cover ◽

Summer Precipitation ◽

Tropical Indian Ocean ◽

Western Pacific Subtropical High ◽

Precipitation Change ◽

Interdecadal Change ◽

Northwestern Pacific ◽

The Tibetan Plateau ◽

Indochina Peninsula

Abstract. Abrupt interdecadal changes in summer precipitation (May – September) over the Indochina Peninsula in the past 40 years have been investigated based on the NCEP-NCAR reanalysis product over 1979–2013 and multiple precipitation datasets. The mechanism for the abrupt change is explored. Results indicate that an abrupt interdecadal change in summer precipitation over the Indochina Peninsula occurred in the middle 1990s, and the annual mean summer precipitation during 1994–2002 increased by about 10% compared to that during 1982–1993. The most significant precipitation change occurred in the central and northern peninsula. Further analysis reveals that the interdecadal decrease in snow cover over the Tibetan Plateau in the winter and spring contributed to the summer precipitation increase over the Indochina Peninsula. The decrease in snow cover over the Tibetan Plateau actually increased the thermal contrast between the Tibetan Plateau and the tropical Indian Ocean-northwestern Pacific, leading to intensified summer monsoon over the northwestern Pacific and the South China Sea. As a result, westerly anomalies occurred from the Bay of Bengal to the northwestern Pacific, while anomalous cyclonic circulation prevailed in the upper levels above East Asia. Correspondingly, the western Pacific subtropical high weakened and shifted eastward. Under the joint effects of the above circulation patterns, the atmosphere became wetter in the Indochina Peninsula and summer precipitation increased. Results of the present study provide a theoretical basis for the prediction of long-term summer precipitation change in the Indochina Peninsula.

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