Late Holocene climatic changes in Garhwal Himalaya

Geochemical study of a 3.55 m long lake sediment core from the Badanital Lake (Garhwal Himalaya) reveals Late Holocene centennial-scale climatic changes. The ecosystem of the tectonically formed lake seems to be controlled by natural and anthropogenic factors. The imprints of four major global events, e.g. 4.2 ka event, Medieval Warm Period (MWP), Little Ice Age (LIA) and modern warming are observed. By using the geochemical parameters, e.g. major oxides and their ratios (CaO/MgO, CaO/TiO2, MgO/TiO2, Na2O/TiO2, TiO2/Al2O3, Na2O/K2O and Fe2O3/TiO2), major elements, chemical index of weathering, chemical index of alteration and loss on ignition, the core profile is divided into six major climatic zones. The sediment accumulation rate was extremely slow during a cold/dry phase from ca. 5.1 to 3.5 ka BP. This was followed by wetter/moist phase from ca. 3.5 to 1.8 ka BP and the area further remained under arid conditions from ca. 1800 to 920 years BP. Almost wet/moist environment prevailed around 920–440 years BP, corresponding to the MWP. The LIA (440–160 years BP) was somewhat cooler, whereas post LIA, particularly from 160 years BP points to modern warming.