A 694-year tree-ring based rainfall reconstruction from Himachal Pradesh, India

Abstract

We developed ring-width chronologies of Cedrus deodara [(Roxb.) G. Don] and Pinus gerardiana (Wall. Ex. Lamb) from a homogeneous moisture stressed area in Kinnaur, Himachal Pradesh. Running correlation using a 50-year window with overlap of 25 years showed strong correlations between these species chronologies during the entire common period (ad 1310-2005). Response function analysis indicated that except for January-February, precipitation has a direct relationship with growth of these species. We therefore combined both the species chronologies to develop a statistically calibrated reconstruction of March-July precipitation that spans from ad 1310-2004, and explains 46% of the variance contained in the instrumental data from the calibration period 1951-1994. In the past 694 years of the reconstruction, the wettest period was in the twentieth century (1963-1992) and the driest in the eighteenth century (1773-1802). The relationships observed between reconstructed precipitation and Indian summer monsoon on interdecadal scale, SOI, PDO and NAO indicate the potential utility of such long-term reconstructions in understanding the large-scale climate variability. Multi-taper method (MTM) spectral analysis indicated significant (p < 0.05) spectral peaks at 2-4, 6, 8, 10, 30, 33, 37 and 40-42 years in the reconstructed precipitation data.