Why are many Tien Shan glaciers receding or remaining still?

In the Tien Shan mountain system, glacial action is currently decreasing, with most glaciers either receding or remaining stationary.1

The state of a glacier is determined by its mass balance, which is the equilibrium between accumulation (income from snowfall, avalanches, or condensation) and ablation (loss through melting, runoff, or calving). When a glacier’s mass balance is negative—meaning the rate of ablation exceeds the rate of accumulation—the glacier shrinks. Conversely, if the income and outgo are balanced, the glacier remains at a constant size.2

The Tien Shan region is characterized by a sharply continental climate with significant aridity, particularly in its interior and eastern sections where precipitation is low. Because these glaciers exist in an environment where snowfall is often limited and summer temperatures can be high, they are highly sensitive to changes in these climatic factors. While most glaciers in the range are currently in decline, it is worth noting that some large glaciers in the inner Tien Shan region have experienced short-term advances since the mid-20th century.341