Executive Summary : | The past few decades have shown an increase in intensity and frequency of severe cyclonic storms in the Indian Ocean region (Deshpande et al., 2021). These cyclonic storms result in major socioeconomic implications. The probable factor for these high intensity storms is varied atmospheric parameters like increased relative humidity, weak vertical wind shear as well as high sea surface temperature (SST) (NMDC, 2021) pointing out at global warming as the major cause in bringing about the highly intensified cyclonic storms. Tropical cyclones (TCs) are accompanied by high wind speed and heavy downpour and they are known to affect mostly equatorial to midlatitude coastal regions. In Indian scenario frequent occurrence of TCs affects major states like Odisha, Tamil Nadu, Gujarat, Andhra Pradesh etc (Yadav et al., 2017). Various cyclones in the past have created major havoc in these states causing adverse effect on human life and economic activity which in turn could substantially threaten the world economy. Therefore, with progressive increase in temperature, a lot of research attention is being focussed on how the intensity of TCs reacts to the warming (Bhatia et al., 2019; Kang and Elsner, 2015; Knutson et al., 2010). Various work has been done to investigate the effect of global warming on maximum TC potential (Bender et al., 2010; Bister and Emanuel, 1998; Knutson et al., 2015). A better understanding of causality of TCs is possible by studying long term TC records in geological time. The availability of long-term data set is hampered by: (i) Validity of long‐term instrumental data series from the past (Sobel et al., 2016) (ii) non-availability of high-resolution robust proxies to establish the paleo TC. Thus, it is of utmost importance to establish robust proxies in geological archives which will help us probe beyond the range of instrumental observation. This technique will be helpful in determining the sensitivity of TC intensity to SST changes. Lake sediments has proven to be continuous proxies within which coarse layers represent high energy event deposits for instance cyclone, floods etc (Gilli et al., 2013; Moreno et al., 2008). For this project we will be choosing four different cyclone prone states in India namely Gujarat in the West Coast, Odisha and West Bengal in east coast and Tamil Nadu in southern part of India. The project involves lacustrine sample collection and working on different inorganic and organic geochemical tracers to detect cyclonic signatures in Holocene. Proxies like grain size, TiO₂/Al₂O₃, SiO₂/Al₂O₃, TOC and C/N ratio, δ¹³Corg and δ¹⁵Nbulk along with sedimentological study to identify rapid depositional layer caused by high frequency events will be used (Zhou et al., 2019). The aim of this project is developing a reliable means of distinguishing cyclonic layers from other landscape perturbations in the absence of instrumental records and to develop a record of cyclones on centennial scale for the Holocene. |