Tree-ring-based temperature reconstruction from the western Himalayan region in northern Pakistan since 1705 C.E.

Abstract

The western Himalayan region in northern Pakistan is one of the most sensitive hotspots to climate change, due to the rapidly increasing population and delicate mountainous ecosystem. The relatively limited observed instrumental record impedes our understanding of long-term climate variability and their assessment. Using standard dendrochronological techniques, a 395-year (1620 to 2014 C.E.) tree-ring chronology of Abies pindrow (Royle) (Himalayan fir) was developed from the western Himalayan region in northern Pakistan. The results of the growth-climate relationship demonstrated that the radial growth of Abies pindrow was limited by minimum temperature. Using a robust reconstruction model, a 310-year (1705 to 2014 C.E.) minimum temperature was reconstructed from the western Himalayan region in northern Pakistan. The reconstructed minimum temperature accounts for 38% variance of the actual minimum temperature, and provides the evidences of Dalton minimum and modern maximum periods. The coldest years in the reconstruction were 1726, 1727, 1892, 1921, and 2001, whereas the hottest years were 1789, 1807, 1814, 1846, 2011, and 2013. Multi-taper method (MTM) spectral analysis showed a significant shorter quasi-cycles (2.3 to 3.5 years) and decadal cycles (11.5 to 17.5 years), suggesting a possible teleconnections with El Niño Southern Oscillation (ENSO), and Northern Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) respectively.