#Continental shelf driver
In addition, the ice shelf basal melting has also been confirmed to be a major driver of ice shelf calving ( Liu et al., 2015). The basal melting of ice shelves is directly affected by the circulations over the Antarctic continental shelf ( Rignot et al., 2013), with cross-shelf heat transport delivered into the sub-ice-shelf cavities ( Herraiz-Borreguero et al., 2015 Nitsche et al., 2017 Nakayama et al., 2019 Tinto et al., 2019). Many ice shelves have been experiencing a net mass loss and thinning due to the enhanced ocean-driven basal melting ( Adusumilli et al., 2020). Ice shelves, as the extensions of grounding ice sheets into the ocean, act to buttress the ice sheet Dupont and Alley, 2005), and thereby the retreat of the ice shelves can accelerate the ice streams into the ocean. Satellite-based observations have revealed that the mass loss of the Antarctic ice sheet is primarily induced by the ocean-driven basal melting of Antarctic ice shelves ( Rignot et al., 2013 Liu et al., 2015 Adusumilli et al., 2020). Consequently, the temporally and spatially averaged basal melting rate of the Amery Ice Shelf reduces by ~13.04% from ~0.69 m yr -1 to ~0.60 m yr -1. Over the inner shelf, the heat transport towards the Amery Ice Shelf reduces by ~18.15% from ~5.95×10 13 J s -1 to ~4.87×10 13 J s -1. The onshore heat transport reduces by ~22.18% from ~5.23×10 13 J s -1 to ~4.07×10 13 J s -1 over the outer shelf. In addition, the corrected bathymetry markedly decreases the heat transport towards the calving front of the Amery Ice Shelf. Sensitivity numerical experiments show that the bathymetric corrections in Prydz Bay have a significant impact on the circulation pattern and onshore warm water intrusions. The corrected bathymetry mainly improves the biased shallow representations in the uncorrected bathymetric data set, with a maximum change of ~500 m deepening in the eastern flank of Prydz Bay. With the aid of in situ hydrographic observations, this study focuses on the correction of an up-to-date bathymetric dataset and the resultant influences on the shelf circulation and the basal melting of the ice shelves. However, due to the paucity of beam echo sounding data, the bathymetric datasets in Prydz Bay still have large uncertainties. In Prydz Bay, the Prydz Bay Gyre and coastal currents are also determined by the continental shelf topography. The bathymetry around Antarctica can govern the shelf sea circulations and play a key role in conditioning water masses. 2Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, China.1Key Laboratory of Marine Hazards Forecasting, Ministry of Natural Resources, Hohai University, Nanjing, China/College of Oceanography, Hohai University, Nanjing, China.Chong Sun 1, Chengyan Liu 2*, Zhaomin Wang 1,2*, Liangjun Yan 1, Yixuan Tao 1, Qing Qin 1 and Jiangchao Qian 1
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