They discover when the Thwaites glacier at the end of the world began to melt. They suggest that the ThWaites Glacier has recorded a significant retreat since the 1940s.
The retreat of these glaciers was probably initiated by an extreme climate pattern from the periodic natural phenomenon known as El Niño that warmed West Antarctica. Once the system becomes unbalanced, the retreat continues, say the authors of the study. They highlight "a vital role in regulating the stability of the West Antarctic Ice Sheet and therefore, in global sea level rise"