# Widespread Climate Change in the Himalayas and Associated Changes in Local Ecosystems

 Title: Widespread Climate Change in the Himalayas and Associated Changes in Local Ecosystems Author: Bawa, Kamaljit S.; Shrestha, Uttam Babu; Gautam, Shiva Prasad Note: Order does not necessarily reflect citation order of authors. Citation: Shrestha, Uttam Babu, Shiva Gautam, and Kamaljit S. Bawa. 2012. Widespread climate change in the Himalayas and associated changes in local ecosystems. PLoS ONE 7(5): e36741. Full Text & Related Files: 3352921.pdf (1.305Mb; PDF) Abstract: Background: Climate change in the Himalayas, a biodiversity hotspot, home of many sacred landscapes, and the source of eight largest rivers of Asia, is likely to impact the well-being of $$\sim$$20% of humanity. However, despite the extraordinary environmental, cultural, and socio-economic importance of the Himalayas, and despite their rapidly increasing ecological degradation, not much is known about actual changes in the two most critical climatic variables: temperature and rainfall. Nor do we know how changes in these parameters might impact the ecosystems including vegetation phenology. Methodology/Principal Findings: By analyzing temperature and rainfall data, and NDVI (Normalized Difference Vegetation Index) values from remotely sensed imagery, we report significant changes in temperature, rainfall, and vegetation phenology across the Himalayas between 1982 and 2006. The average annual mean temperature during the 25 year period has increased by 1.5$$^\circ$$C with an average increase of 0.06$$^\circ$$C yr$$^{−1}$$. The average annual precipitation has increased by 163 mm or 6.52 mmyr$$^{−1}$$. Since changes in temperature and precipitation are immediately manifested as changes in phenology of local ecosystems, we examined phenological changes in all major ecoregions. The average start of the growing season (SOS) seems to have advanced by 4.7 days or 0.19 days yr$$^{−1}$$ and the length of growing season (LOS) appears to have advanced by 4.7 days or 0.19 days yr$$^{−1}$$, but there has been no change in the end of the growing season (EOS). There is considerable spatial and seasonal variation in changes in climate and phenological parameters. Conclusions/Significance: This is the first time that large scale climatic and phenological changes at the landscape level have been documented for the Himalayas. The rate of warming in the Himalayas is greater than the global average, confirming that the Himalayas are among the regions most vulnerable to climate change. Published Version: doi:10.1371/journal.pone.0036741 Other Sources: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3352921/pdf/ Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:10384786 Downloads of this work: