Transition of the Karakoram anomaly under emerging hydroclimatic trends

The presence of a Karakoram Anomaly (KA) where, in contrast to most global glaciers, regional glaciers are reported to have either stable or quasi-positive mass balance commonly has been challenged by recent glacier mass balance studies in response to decadal variability in temperature and precipitation. Here, we examine the amplitude and temporal evolution of the KA by observing hydroclimatic (temperature, precipitation, snow and streamflow) trends in the extensive snow/glacier-fed Hunza River Basin (HRB). We use daily time series of in situ hydroclimatic data in combination with (reanalysis/satellite) products (1995-2021), and MODIS Snow Covered Area (SCA) (2001-2020) to quantify the persistence of KA. The Wavelet Transfer Function (WTF), Innovative Trend Analysis (ITA), and Mann-Kendall (MK) tests validated the direction and extent of secular hydroclimatic trends. We further establish a hydroclimatic relationship for HRB using an Artificial Neural Networks (ANNs) incorporating more extensive variables of relative humidity and solar radiation for the model robustness. Transitioning of the KA to glacier mass loss is confirmed to be a result of climatic trends, and specifically summertime - focused enhanced intense warming, have triggered regional snow cover removal and increased streamflow. Mean annual near-surface temperatures in Khunjerab significantly increased by 0.33 and 0.26 ^∘C/decade from (1995-2021) based on analyses of data from ERA5 and stations, respectively. The SCA trends are primarily negative in summer and positive in winter, corresponding to enhanced winter flows. The WTF and ITA indicate a significant decline in SC during January, April, May, August and October. Temperature exhibits a significant causal relationship with streamflow, snow and relative humidity. Granger's index and ANNs demonstrate that 2-m temperatures, snow cover, relative humidity, and solar radiation have stronger correlations to streamflow than precipitation.