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Aerosol characteristics and climatic implications derived for selected locations of the north‐eastern region of India and adjoining locations Thimphu (THM), Dhaka (DAC) and Banmauk between 22–30°N and 88–98°E are reported. The region is found to reveal a distinct spatio‐temporal variability in aerosol distribution, with highest climatological mean aerosol optical depth at 550 nm (AOD550) at DAC (0.65 ± 0.07) and lowest at the high altitude location THM (0.19 ± 0.02). Seasonally the maximum AOD550 is observed in the pre‐monsoon season. Moderate resolution imaging spectroradiometer Level‐3 Collection 6 AOD550 and Ångström exponent (AE) exhibit a significant and simultaneous increasing trend in the range of ∼0.003 year−1 to 0.012 year−1 and ∼−0.001 year−1 to 0.020 year−1, respectively, during the period 2001–2014. Together with AE, increasing trend of total ozone mapping spectrometer and ozone monitoring instrument‐retrieved aerosol index (∼0.001 year−1 to 0.007 year−1 during 1979–2014) signifies an increase in anthropogenic aerosol loading, leading to an increase in number density of cloud condensation nuclei and decrease/increase of cloud effective radius /cloud optical depth (COD). This is further associated with overall decreasing trends of rainfall rate over this complex monsoon region. A slow increase in maximum temperature (Tmax) (∼0.008 °C year−1 to 0.049 °C year−1) compared to that in minimum temperature (Tmin) (∼0.007 °C year−1 to 0.068 °C year−1) is attributed to solar dimming due to increasing aerosol loading and COD (∼0.056 year−1 to 0.15 year−1). A decrease in high‐level cloud (CODhigh) counteracts decreasing trends of ground reaching solar radiation over a few locations, including Dibrugarh. This study is important from an aerosol radiation interaction and aerosol cloud interaction viewpoint, which facilitates in reaching a closure of model simulated present day climate change and future climate projections.

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