Estimate of glacial isostatic adjustment uplift rate in the Tibetan Plateau from GRACE and GIA models

The Tibetan Plateau is located in central Asia with the highest mountain and extraordinary size, where geodynamic processes are very complex. The Glacial Isostatic Adjustment (GIA) effect in the Tibetan Plateau has been highly controversial because the past and present dimensions of ice sheets are suffering from large uncertainties. Larger differences in GIA estimates are found from different models or analyses based on the possible ice sheet and glacial history in Tibet. Present-day space geodetic techniques, such as Gravity Recovery and Climate Experiment (GRACE), are able to detect the vertical mass displacement and GIA uplift. In this paper, the GIA effects in the Tibetan Plateau are estimated and evaluated with GRACE measurements and GIA models. Four global GIA models and four regional models (RM) are respectively used to estimate the GIA uplift rates with various ice sheet models and viscoelastic Earth models, which are compared with GRACE measurements. Results show that the uplift rates of GIA effects range from 1 mm/yr to 2 mm/yr in the most part of the Tibetan Plateau. The global GIA model constructed by Peltier (Peltier, 2004) provides better estimations of the GIA in the Tibetan Plateau than the other three models.