对2002—2022年观测数据的分析显示，思韦茨冰川东部冰架剪切带的裂缝在约20年内快速扩展并削弱结构稳定性。裂缝增长使冰架与北端海底隆起（锚固点/海底脊）的连接逐步变弱，从而加速上游冰流。

裂缝扩展呈两阶段：先出现沿流向的长裂缝并向东延伸，部分长度超过8公里且贯穿冰架；随后出现大量横向短裂缝，单条小于2公里，使裂缝总长度成倍增加。卫星图像显示，裂缝总长度由2002年的约165公里增至2021年的约336公里，而平均单裂缝长度由3.2公里降至1.5公里，表明小裂缝占比上升与应力状态显著转变。

GPS（2020—2022年）与卫星序列记录到反馈回路：裂缝加速冰流，速度上升又促生新裂缝。2020年冬季，剪切带结构变化以约每年55公里向上游推进，且剪切形变速率出现陡增。由于其处在“反坡床”，一旦退缩开始更可能走向不可逆；其总质量足以使海平面上升约65厘米，既有模型估计未来40年基线与冰架将以接近每年1公里的速度后退。

Analysis of observations from 2002–2022 shows that cracks in the Thwaites Glacier’s eastern ice-shelf shear zone expanded rapidly over ~20 years, weakening structural stability. As cracking grew, the link between the shelf and its northern ocean-floor ridge (anchorage) progressively weakened, which in turn accelerated upstream ice flow.

Crack growth occurred in two stages: long, flow-parallel fractures extended eastward, with some exceeding 8 km and spanning the shelf; later, many short cross-flow cracks (<2 km each) appeared, effectively doubling total fissure length. Satellite mapping indicates total crack length rose from ~165 km (2002) to ~336 km (2021), while mean crack length fell from 3.2 km to 1.5 km—evidence of a shift toward many smaller fractures and a changed stress regime.

GPS (2020–2022) and satellite time series capture a feedback loop: cracks speed up ice flow, and faster flow generates new cracks. In winter 2020, structural change in the shear zone propagated upstream at ~55 km/year, coinciding with a sharp jump in shear deformation. Because Thwaites sits on a reverse-slope bed, retreat is more likely to become irreversible; its mass could raise sea level by ~65 cm, and models estimate ~1 km/year baseline and shelf retreat over the next 40 years.