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Climate driven changes have impacted various civilizations and have major influence on human population globally. Remote regions such as the Himalaya also archived these climatic events in various proxies. The Eastern Himalaya region has recorded the Holocene climate change events in numerous proxy records. A multi–proxy record of the early to late–mid Holocene climate change from the catchment of PankangTeng Tso (PT Tso) Lake at an altitude of 3935 m asl in the Tawang district of Arunachal Pradesh was studied. A 90 cm sediment profile showed a synchronous pattern of Holocene climate changes in the palynological, environmental magnetic and carbon isotope data recorded. Dominant cold-humid conditions at 4625 cal yr BP followed by a cold-dry period was documented in the proxy data. The vegetation vis–a–vis climate varied throughout the Holocene and cold–dry conditions along with sub-alpine vegetation prevailed in the region around the “4.2ka event”. Human activities and environmental changes in the Tawang district during the Holocene probably impacted the vegetation during this significant period of the development and demise of major global civilizations.

Tree-rings of Pinus kesiya from southern region of Manipur, Northeast India were used to develop chronologies of multiple tree-ring parameters that are: total-ring width (TRW), earlywood width (EW), latewood width (LW) and adjusted latewood (LWadj). The time span of these chronologies is 39 years (1980–2018 C.E.) and we compared their growth responses with monthly and daily climatic records. The comparison revealed a broadly consistent pattern of climate sensitivity with daily climate exhibiting higher correlation. The climate signals during pre-monsoon (March–May) were recorded in TRW and EW, whereas late-monsoon to post-monsoon climate signals were recorded in LW and LWadj. The spatial correlation analysis of tree-ring parameters and global sea surface temperature (SST) showed a positive relationship between tree growth with tropical Pacific Ocean and Indian Ocean during winter (December–February) and pre-monsoon (March–May) seasons. The LW and LWadj were also correlated with peak summer monsoon (July–August) SST over the tropical Pacific Ocean. IADFs observed in EW (E-IADF) were caused by dry and warm conditions during March–April. IADFs in LW ( L -IADF) occurred due to a combination of enhanced rainfall and temperature during post-monsoon (October–November) season. Evidence of stand-specific micro-climatic conditions in the formation IADFs in this species was also found. This study showed that multiple parameters of P. kesiya provides a lucid understanding of climate response on its growth and can be considered as a proxy for studying sub-seasonal changes in past environmental conditions in longer records.

Tree rings from forest-steppes of temperate continental Asia are useful proxies for the moisture regime reconstructions, encompassing environmental variations such as warming climate, changing frequency and intensity of droughts. Heterogeneity of precipitation leaves open the question of the probability of spatially large-scale droughts in this macro-region. Theoretically, such events could be driven by global tele-connections and/or common astronomic cycles. We have attempted the precipitation reconstructions of two distant (~1000 km) intermountain valleys in South Siberia, based on the tree ring width of Pinus sylvestris L. To enhance the quality of the precipitation reconstruction models, networks of existing tree-ring data were expanded and daily precision of instrumental precipitation series was implemented for calibration. Within-region (150-200 km) common signal between local chronologies r=0.37-0.90 (p Data Availability Statement Temperature and precipitation series of climatic stations were obtained from the website of All-Russia Research Institute of Hydrometeorological Information, World Data Centre (RIHMI-WDC, http://meteo.ru/data ). Other climatic time series and solar activity series were obtained from the website of The Royal Netherlands Meteorological Institute (KNMI) Climate Explorer ( https://climexp.knmi.nl ). Used in the study tree-ring width measurements will be submitted to the International Tree-Ring Data Bank (ITRDB; https://www.ncei.noaa.gov/products/paleoclimatology/tree-ring ) upon publication of the manuscript and with reference to it.

We present a 180-years long (1824–2003C.E.) tree–ring width chronology of the fast growing broadleaf tree Toon (Toona ciliata Roem.) from the subtropical wet hill forests of Kalimpong, in the eastern Himalaya of India. The majority of tree ring studies conducted in the Himalaya have been based on conifers. Our analyses demonstrate that winter temperature prior to the season of growth, current year April precipitation and April–May drought (scPDSI) exhibit direct relationship with the ring–width chronology when correlated with monthly or seasonal climate data. The observation of the tree–growth and climate relationship showed that optimum temperature, precipitation and soil moisture together serve to modulate the radial growth of Toon in the region, however the mean minimum temperature of winter season (October–February) is the most significant climatic factor. Based on the expressed population signal (EPS) statistic, our record is reliable only back to 1945C.E., however this study clearly establishes the dendroclimatic potential of this tropical broadleaf species to carry out future tree–ring based long–term climate reconstruction in the sub-tropical Himalaya.

Vegetation and climate during later part of Late Pleistocene have been reconstructed from Ziro valley, Arunachal Pradesh, Eastern Himalaya based on pollen data along with carbon isotope and magnetic susceptibility data The study reveals that the area and the vicinity is occupied by mixed broad leaved – conifer forest and pine grass savanah at variable densities at least since 66,000yr BP. The phases of expansions and declines of Oaks with decline and increase of Pines and grasses probably occurred under increase (warm–moist) and decrease (cool–dry) of S.W. monsoon precipitation respectively. The increasing trend of S.W. monsoon and temperature is recorded during ∼44,000 to 34,000 cal yr BP synchronizing with the peat development, and which peaked at around 35,000 cal yr BP. This may link to the interstadial phase during the last major glacial cycle in the Himalayan region. It is also reflected in the decline of δ13C value indicating dominance of C-3 type of vegetation. The increased values of χFD%, and lower values χLF magnetic susceptibility, recorded during the phase of the peat deposit, further advocate's higher monsoon intensity. Impact of expansion of glacier felt with peak (LGM) around 20,000 cal yr BP is perceived. Tree line had moved to lower altitudes due to increased aridity and low temperature. During this time existence of savannah type of vegetation is also evident by the increase of C4 taxa. Decreased FD% and increased χLF susceptibility also indicate reduced S.W. monsoon intensity.

This paper deals with the review of pollen based palaeoclimatic records available from the South-west monsoon dominated northeast part of India. Here, a complete overview of available Late Pleistocene–Holocene records of the past vegetation vis-a-vis climate is structured based on a latitudinal subdivision of the region. The broad spectrum of the past climate in terms of humid/dry, warm/cold inferred by variations of some key pollen or group of pollen taxa is depicted diagrammatically, thereby providing a glimpse of spatio-temporal vegetation vis-a-vis climatic changes. Here, we attempt to create a standard diagrammatic scale with more reliability than using relative terminology to infer past climate records, based on pollen data from sub-surface sediments.