Spatially varying surface seasonal oscillations and 3-D crustal deformation of the Tibetan Plateau derived from GPS and GRACE data

<p>&#160; &#160; &#160; &#160; &#160;The Tibetan Plateau (TP) experiences complex mass transfer and redistribution due to the effects from internal earth dynamics and external climate change, such as, land water change, crustal uplift, surface denudation, and Moho interface change. These phenomenas are accompanied by the gravity field change and could be observed by the Gravity Recovery and Climate Experiment (GRACE). This study applies GRACE data to estimate the corresponding mass changes expressed by water equivalent height (EWH) anomaly of the TP. In addition, we use ICESat data and hydrological models to estimate the effects of hydrological factors (lake, glaciers, snow, soil moisture, and groundwater), to separate them from the comprehensive mass field to obtain the tectonic information. The total hydrological contribution to the average EWH change is -0.30&#177;0.21 cm/yr. We further estimate the rates of tectonic uplift and denudation based on GNSS and denudation, with results of 0.71&#177;0.46 mm/yr and 0.38&#177;0.10 mm/yr, respectively. Removing the effects of hydrological change, surface displacements and GIA from the GRACE data, we obtain the EWH change contributed from interior mass change of 0.21&#177;0.27 cm/yr, which is equivalent to a mean Moho interface uplift rate of 3.63&#177;4.32 mm/yr. Final results show that the crustal thickness of the northern TP is thinning because of the upwelling of Moho interface and the southern TP is thickening along with Moho deepening, coinciding with the tomographic results.</p><p>Key words: the Tibetan plateau, mass transfer, land water change, Moho interface change, GRACE</p>

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Active crustal deformation beyond the SE margin of the Tibetan Plateau: Constraints from the evolution of fluvial systems

Global and Planetary Change ◽

10.1016/j.gloplacha.2009.03.008 ◽

2009 ◽

Vol 68 (4) ◽

pp. 395-417 ◽

Cited By ~ 28

Author(s):

Rob Westaway

Keyword(s):

Tibetan Plateau ◽

Crustal Deformation ◽

The Tibetan Plateau ◽

Fluvial Systems

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Changes in Moisture Flux over the Tibetan Plateau during 1979–2011 and Possible Mechanisms

Journal of Climate ◽

10.1175/jcli-d-13-00321.1 ◽

2014 ◽

Vol 27 (5) ◽

pp. 1876-1893 ◽

Cited By ~ 79

Author(s):

Yanhong Gao ◽

Lan Cuo ◽

Yongxin Zhang

Keyword(s):

Tibetan Plateau ◽

Moisture Flux ◽

Monsoon Circulation ◽

The Tibetan Plateau ◽

Transient Eddy ◽

Wet Season ◽

Dynamic Component ◽

Westerly Jet ◽

East Asian Westerly Jet ◽

Spatially Varying

Abstract Changes in moisture as represented by P − E (precipitation − evapotranspiration) and the possible causes over the Tibetan Plateau (TP) during 1979–2011 are examined based on the Global Land Data Assimilation Systems (GLDAS) ensemble mean runoff and reanalyses. It is found that the TP is getting wetter as a whole but with large spatial variations. The climatologically humid southeastern TP is getting drier while the vast arid and semiarid northwestern TP is getting wetter. The Clausius–Clapeyron relation cannot be used to explain the changes in P − E over the TP. Through decomposing the changes in P − E into three major components—dynamic, thermodynamic, and transient eddy components—it is noted that the dynamic component plays a key role in the changes of P − E over the TP. The thermodynamic component contributes positively over the southern and central TP whereas the transient eddy component tends to reinforce (offset) the dynamic component over the southern and parts of the northern TP (central TP). Seasonally, the dynamic component contributes substantially to changes in P − E during the wet season, with small contributions from the thermodynamic and transient eddy components. Further analyses reveal the poleward shift of the East Asian westerly jet stream by 0.7° and poleward moisture transport as well as the intensification of the summer monsoon circulation due to global warming, which are shown to be responsible for the general wetting trend over the TP. It is further demonstrated that changes in local circulations that occur due to the differential heating of the TP and its surroundings are responsible for the spatially varying changes in moisture over the TP.

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