How did permafrost thaw affect regional climate and environment in continental Siberia?

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Current studies concerning Siberian permafrost have aimed to reconstruct the history of permafrost growth in past climates, investigate permafrost decline in association with Antarctic sea ice, and examine the relationship of permafrost to carbon cycle dynamics (Vaks et al. 2013; Vaks et al 2020; Lechleitner et al. 2020). Prior studies have concentrated on niche timescales, typically the past 500,000 years to assess the relationship between global temperature and permafrost extent (Vaks et al. 2013; Pacton et al. 2013), although some studies are on relatively recent timescales (i.e. Vaks et al. 2020). The research aims of this study would primarily pick up from the limitations acknowledged by Lechleitner et al (2020) concerning the capability of speleothem records to identify the chemical signatures of permafrost degradation, the timescale that this occurs on, as well as the capability to reconstruct past climate and the identification of chemical signals governing these processes (Leichleitner et al. 2018). However, this study would essentially develop on existing literature by distinctly focusing on interglacial permafrost thawing paleoclimatic records from ~420,000 years ago to identify past climate dynamics associated feedbacks and the spatio-temporal behaviour of permafrost under different climate conditions (i.e. temperature). Therefore, to address the working question, this study would attempt to answer the following research questions (RQ): 1) Can the location and speed of permafrost thaw in Central Siberia be reconstructed under different warming scenarios? 2) What are the repercussions for moisture transport and Siberian ecosystems? 3) Can speleothems from Botovskaya cave accurately reconstruct past temperature changes?4) What is the relationship of speleothem proxies to local and global climate conditions?