Driven by the strength in local land–atmosphere coupling, inter‐annual variability of larger‐scale atmospheric circulations primarily determines a glacier's response to warming in high Asia. In this study, micrometeorological measurements in conjunction with regional reanalysis data set were analysed to examine seasonal land–atmosphere coupling strength at a typical central Himalayan (CH) glacier where the influence of Indian summer monsoon (ISM) predominates relative to winter‐westerlies. Energy–water (E–W) exchange and coupling behaviour were studied for the Pindari glacier based on sub‐hourly measurements of radiative–convective flux, state parameters, and sub‐surface thermal profiles using cross‐correlations between various E–W balance components. Coupling was positive in summer and winter accumulation seasons. However, it remained strongest during ISM. Coupling reversed during seasonal transition phases concurrent with distinct seasonality in E–W components. Lead–lag relation between some variables showed strong association at diurnal‐scale (VPD–Rn; VPD–LE; Rn–G), whereas some persisted beyond months (Rn–LE; Bowen ratio–precipitation; surface–air temperature). Weak association of variation of latent heat flux (LE) and rainfall was found during ISM at local scale than at regional scale, but with a lag, which was more prominent at regional scale. These observations indicate a seasonally variable coupling between E–W balance components through response–feedback mechanisms. Cross‐correlations of daily mean values of energy fluxes and meteorological variables reveal that Rn and air temperature are the prime drivers of energy balance. Net radiative energy (Rn) dominates energy exchanges at the glacier–atmosphere interface (governed primarily by the variation in net shortwave radiation), contributed on average 62% of the melt energy. However, sub‐surface heat flux along with the turbulent fluxes was the energy sinks of 24 and 15%, respectively. This study would help understand and parameterize E–W exchange pathways for ISM dominated CH glaciers in coupled glacier–climate models.

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In present communication, a methodology is described to compute total radiation falling on inclined plane by employing the measured global and diffuse radiation data on horizontal surface of India. Five stations Jodhpur, Kolkata, Bangalore, New Delhi, and Srinagar representative of five different climatic zones-hot and dry, hot and humid, temperate, composite and cold, respectively are chosen for the study.The measured data of 15 years (from 1986 to 2000) are exploited and statistical analysis is carried out for the monthly mean daily data. Isotropic model of Liu and Jordan and anisotropic model of Hay are applied in the estimation of total radiation on tilted plane facing south with various slopes and an inter-comparison between these two models is made to ensure their adaptability in different climatic regions of India. Four tilt angles viz. latitude, latitude 115 N, latitude-15 N and 22.5 N are considered and both the models are used for computation of total radiation to test whether variation in tilt angles affect the reliability of models for any particular climatic zone.Furthermore, for realistic predictions, accuracy of isotropic and anisotropic models is tested through three statistical parameters and isotropic model is found fit for first four climatic zones of India while for cold region, performance of anisotropic seems better.

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