Tree ring width variations over western Himalaya in India and its linkage with heat and aridity indices

Tree ring chronologies from different sites of western Himalaya have been carried out in relation to rainfall, temperature, palmer drought severity index, and heat and aridity indices of the region. The first principal component which was developed using the multi-sites chronologies of Himalaya has explained 50% common variance is positively correlated with rainfall, aridity and palmer drought severity index and negatively with temperature and heat index during spring season (February–May). The existence of strong correlation indicates that heat and aridity indices over the region might be one of the important climatic parameters which play the significant role in tree growth process. Particularly, heat index’s influence over the region indicated larger impact on annual ring width patterns than temperature.