Sri Durgesh Nandini

Sri Durgesh Nandini


Institute and email: MARUM, University of Bremen, GERMANY and linkedin profile:

Statement of interest: I am an Early Stage Marie-Curie Researcher (ITN_PRIDE) doing my PhD in the form of a Research Scientist in Climate Modelling at the University of Bremen, Germany. My science interests span oceanography, climate, and biogeochemistry, with particular emphasis on the application of numerical models and data analysis methods to global-scale questions. I have a Masters in Climate Science, postgraduate in Climate Change, Bachelors in Marine Science. I was a Visiting Researcher at Woodshole Institute (Boston), University of Hawaii, IRD; SPC (New Caledonia), CNRS/CLS (Toulouse), CSIRO (Tasmania), AWI and ZMT (Germany) and University of Reading (England). My 10years of global career exposure in climate change & modelling expertise (FIJI, USA, Australia, England, Germany, France, New Caledonia) has endowed me with great potential for an outstanding international career collaborations. I am also part of Bremen International Graduate School for Marine Sciences (GLOMAR). My hobbies include Ashtanga Yoga (teacher) and SCUBA diving.

Project description

Late Pleistocene to Future Hydroclimate Variations in the Caspian Sea Catchment: A Climate Modeling Study

Currently, I am using the CESM1.2.2 model to understand the Hydroclimate Dynamics in the Late Quaternary Ponto-Caspian Region (the Black, Caspian Sea). The outputs of these are shared and used by other Early Stage Researchers in this project.

Throughout the late Pleistocene to present, the Caspian Sea Level (CSL) has varied by ~150 m, with significant recent impacts on the coastal communities, economy and the regional ecosystem. The origin of the key drivers (hydro-climatic processes) and future CSL changes remain uncertain. Here, we examine and discuss the impacts from simulated past, present and future climate states on the hydroclimate (precipitation minus evaporation; P-E) of the CS basin. Simulations are performed with the state-of-the-art coupled Community Earth System Model (CESM1.2.2) for the Last Interglacial (127 ka before present), Marine Isotope Stage 3 (35 ka) (stadial and interstadial states), the Last Glacial Maximum (21 ka), Heinrich Event 1 (15.2 ka), the early Holocene (9 ka), the pre-industrial (1850), the historical period (1850-2005) and the future (2005-2100) (Representative Concentration Pathways RCP4.5 and RCP8.5) at different model versions and atmospheric grid resolutions (1° and 2°). We identify the 35 ka and LGM climate states to be colder and drier compared to present-day with lower precipitation (~1 mm/day) over the CS basin. The Heinrich Event 1 (colder and drier than the above) P-E (~1.5 mm/day) shows even lower precipitation over the CS. However, small P-E anomalies occur for the warmer and wetter climate states of the Last Interglacial and the early Holocene (~0.5 mm/day) with slightly more precipitation over the CS basin. Lastly, the RCP8.5 suggests P-E decrease compared to present (~0.1 mm/day) linked to enhanced evaporation over the CS. The above time slices correspond to geologic timespans of paleo-lake level reconstructions which hypothesize that fluctuations in ancient CSL high and low stands were driven by changes in P-E. Hence, our modelled results may help interpret these reconstructions with respect to the role of changes in P-E. Moreover, as simulated future P-E changes are well within the range of those simulated for past climatic periods, studying such periods can improve projections of future hydro-climatic sea-level changes in the CS region.