The following graph from the paper provides a nice summary: https://i.postimg.cc/g29fzpW1/sustained-mass-loss.png https://i.postimg.cc/g29fzpW1/sustained-mass-

The following graph from the paper provides a nice summary: https://i.postimg.cc/g29fzpW1/sustained-mass-loss.png https://i.postimg.cc/g29fzpW1/sustained-mass-loss.png SMB (surface mass balance; blue) describes mass that is gained or lost from the surface of the ice sheet, presumably due to weather/climate conditions of that particular year, such as the air temperature, precipitation, etc. D (discharge; red) describes the mass that is lost by the flow of glaciers, which reflects thermal and mechanical stresses within the ice sheet. As you can see, D doesn't change very much with the year, but around 2005 it became "macroscopic". The ice sheet was already shrinking by 2005, but both the SMB and D drivers have increased dramatically since then. A poster above quotes one of the researchers saying that if we went back to a climate that we had 20-30 years ago, the mass loss would not stop. What I infer that he means is that if we went back to the atmospheric conditions of 30 years ago, then SMB would quickly return to its prior behavior, but we have no way of knowing how long it would take D to return to normal, if it would do so at all. A corrigendum is that the climate of 30 years ago was already much warmer than the preindustrial norm; in order to return to "normal" we should go back 100 years, and because of this it may be possible that the ice sheet was already warming internally 30 years ago and would have reached this point albeit more slowly had those conditions been maintained.