## 1 Introduction  
Changes in glacier mass at the \"three poles\" of the Earth's South Pole, North Pole, and Mount Qomolangma are particularly sensitive to climate change and serve as crucial indicators of global warming [1, 2]. The monitoring of wide-area glacier flow velocity is of great value for glacier mass balance, global sea level change, and ecosystem health. Svalbard, one of the largest glaciated regions in the Arctic, encompasses an ice mass of approximately 36,600 km\({}^{2}\), with about 90% of its glaciers having experienced deglaciation [3, 4]. Since the 1950s, numerous countries and organizations have conducted glaciological studies in Svalbard, focusing primarily on material balance, glacier structure, meteorology, hydrology, and glacier movement [5]. Among them, glacier movement is a more reliable and intuitive evaluation index used to reflect the change in glacier quality [6].  
At present, the techniques used to measure glacier morphology/kinematics mainly include flower-pole measurement, photogrammetry, and radar remote sensing [7]. With advantages in all-day and all-weather monitoring, the radar remote sensing technology represented by spaceborne Synthetic Aperture Radar (SAR) are widely used in obtaining the surface texture and morphological change information of glacier areas [8, 9]. Sentinel-1, as an open-source SAR data provider, features high temporal resolution, wide coverage, and strong multi-polarization capabilities, offering data support for large-scale interferometry SAR research. The satellite's data have been widely applied in various fields, such as subsidence monitoring, DSM inversion, and glacier velocity monitoring [10, 11, 12].  
In recent years, researchers have used differential interferometry based on SAR data (D-InSAR), pixel offset tracking (POT), and sub-aperture differential interferometry (MAI) to monitor the surface motion of the \"three-pole\" glacier [13; 14]. The InSAR/MAI technology based on phase difference is difficult to use to monitor the rapid surface deformation in glacier area due to the influence of phase spatiotemporal incoherence [15]. POT involves tracking the movement of individual pixels in radar images over time to calculate the displacement of the surface. As it provides high-resolution data on surface dynamics in various environmental conditions, the POT method is particularly useful for measuring the flow velocity of glaciers [16; 17; 18].  
In recent decades, scholars have conducted monitoring studies on the surface velocity of some glaciers in Svalbard [19; 20; 21; 22; 23]. However, the impact of global warming on the \"three polar\" glaciers is systematic, and it is difficult to monitor the flow velocity of individual glaciers to reflect the overall state of glacier mass balance. In this situation, the wide-area monitoring of the spatial-temporal evolution characteristics of glacier kinematics in Svalbard is critical in assessing the overall stability and development status of glaciers in Svalbard from a large perspective, and providing basic data support for the dynamic change in glacier mass balance.  
Therefore, this paper addresses the technical bottlenecks in the wide-area POT SAR monitoring of glacier velocity, such as noise suppression and matching window optimization issues, and develops an enhanced wide-area POT glacier surface flow velocity monitoring method for large-scale glacier monitoring. The Sentinel-1 satellite SAR data set covering seven maps of Svalbard in 2021 is used to monitor the current situation of glacier flow velocity throughout the island. Using the Monacobreen glacier as a case study, the factors affecting the flow velocity of the glacier surface are discussed and analyzed, which provides valuable insights for wide-area glacier velocity monitoring.