Congratulations!Koushikh Karunakar successfully presented his MSc thesis

13 June 2023

Photo: private

His thesis titled 'Simulated Climate Variability around the End of the Mid-Holocene’ was supervised by Prof. Dr. Martin Claussen (Universität Hamburg, MPI) and Dr. Roberta D'Agostino (The Institute of Atmospheric Sciences and Climate (CNR-ISAC), Italy).

Holocene, the present interglacial and current epoch, started around 11,700 years ago which is further subdivided into three ages. Koushikh investigated the simulated climate variability at the end of the Mid-Holocene (around 4200 years back) using a new set of full-forcing (Bader et al. 2020; Dallmeyer et al. 2021) and slow-forcing (Brovkin et al. 2019; Dallmeyer et al. 2020) transient simulations of last 8000 years simulated using the Max Planck Institute Earth System Model (MPI-ESM). Both simulations are forced by orbitally driven insolation, temporal changes in greenhouse gas concentrations, land use changes, and stratospheric ozone, while the full forcing simulation is additionally forced by stratospheric volcanic aerosol distribution and spectral solar irradiance. The focus on this period is due to the occurrence of the 4.2 event, a rapid climatic event revealed in many climate reconstructions (Berkelhammer et al. 2012) that resulted in near synchronous abrupt megadroughts in different parts of the tropics and sub-tropics. The exact cause for the onset of this event is still not understood (Wanner et al. 2008).
The aim of this thesis is twofold: (1) to analyze the simulated climate variability of the MPI-ESM at the end of mid-Holocene and thereby check for big drought spells in the simulations and (2) to carry out the climate variability analysis with full and slow forcing transient Holocene simulations to analyze the Holocene climate variability with and without volcanic forcing.
Most of the abrupt climatic intervals of the Holocene coincide with major civilization disruptions, therefore investigating the potential causes for such events is useful and might be informative for planning adaptation strategies in the future.

I was part of the Climate Vegetation Dynamics group at MPI.
In the future, I will be looking to join companies that deal with and address the broad aspects of climate change, sustainable business transformation, and strategy development to name a few.