Natural unforced variability in global mean surface air temperature (GMST) can mask or exaggerate human-caused global warming, and thus a complete understanding of this variability is highly desirable. Significant progress has been made in elucidating the magnitude and physical origins of present-day unforced GMST variability, but it has remained unclear how such variability may change as the climate warms.

Ice-albedo feedback due to the albedo contrast between water and ice is a major factor in seasonal sea ice retreat, and has received increasing attention with the Arctic Ocean shifting to a seasonal ice cover. However, quantitative evaluation of such feedbacks is still insufficient. Here we provide quantitative evidence that heat input through the open water fraction is the primary driver of seasonal and interannual variations in Arctic sea ice retreat.

The history of glacier length fluctuations serves as a reliable indicator of the past climate. In this paper, a numerical flowline model has been used to study the relationship between length variations of Chhota Shigri glacier and local climate since 1876. The simulated front positions of Chhota Shigri glacier are in agreement with those observed. After a successful simulation of the past retreat, the model was also used to predict future evolution of the glacier for the next 100 years under different climatic scenarios.