I am involved in teaching and research as Professor at the Environmental Science and Engineering Department, IIT Bombay since December 2007. I am also an associated faculty member of Interdisciplinary Programme in Climate Studies (currently DST - Centre of Excellence in Climate Studies) and Centre for Urban Science & Engineering , IIT Bombay. Before joining IIT Bombay, I worked as a Post-Doctoral Fellow at the University of Western Ontario , Canada under the mentorship of Prof. Slobodan P Simonovic . I obtained my Ph.D. on “Uncertainty Modeling in Water Resources Systems” from Indian Institute of Science (IISc), Bangalore, India under the supervision of Prof. P. P. Mujumdar . My primary research interest focuses on Environmental Systems Analysis (Water quality management, Solid waste management), Uncertainty Modeling, and Risk-Vulnerability Analysis to Climate-induced Natural Hazards, Climate change impact assessment. I upgraded my Masters degree to Ph.D. programme through the recommendation, decided on academic excellence basis, by the Senate Committee, IISc Bangalore. I also received BOYSCAST fellowship from Department of Science and Technology (DST), Govt. of India to pursue research at Duke University, North Carolina, USA. I have taught more than 35 undergraduate and postgraduate level courses at IIT Bombay, and supervised 11 and co-supervised 4 Ph.D. scholars till date. I am sincerely looking forward to explore new research avenues in the domain of Environmental and Climate Systems.

I am currently pursuing my Ph.D. in the Department of Environment Science and Engineering and working with Prof. Subhankar Karmakar. I am working towards understanding the sensitivity of various input parameters of a flood model. And find out which set of input parameters are most sensitive, such that the decision-makers can take informative decision during data monitoring, collection, and retrieval of these data. We are also doing some flow and stage data monitoring at the station level. And also, validation of model outputs using remote sensing data. In various climate forecasting models’ sensitivity analysis is generally performed. We would like to perform sensitivity analysis for flood modeling parameters such that we can improve the model output accuracy. Therefore, improving the model’s over-all performance.

Presently there are no such flood modeling software that allows us to perform such sensitivity analysis within its platform. If inclusion of a sensitivity analysis framework can be done, in a flood modeler then evaluation of flood risk, flood hazard, flood forecasting can be performed with high degree of accuracy. The calculation of the sensitivity of various input parameters has been done in terms of Kullback–Leibler entropy or KL-divergence (D-KL). We have developed a sensitivity analysis framework and have already tested it over a for a rural catchment (Floodplains of the Shilabati River, Paschim Medinipur), that have been presented in AGU fall meeting 2021.The work is been published in the Journal of Environmental Management, Mondal et al., 2023. We are now working to test the same framework for an urban catchment (Mithi River catchment, Mumbai). You can find me in ESRL, second floor in the Environment Science and Engineering Department (ESED) at IIT Bombay.

I am currently pursuing my Ph.D at the Indian Institute of Technology, Bombay (IITB), in the Interdisciplinary Programme (IDP) in Climate Studies since 2019. I am working with Prof. Subhankar Karmakar, Prof. Pradip Kalbar and Prof. Arpita Mondal on the topic “Mapping social vulnerability and risk to hydro-climatic extremes over India”. In 2016, I graduated from Mahatma Gandhi University, Kottayam, in Bachelor of Technology (B.Tech) degree in Civil Engineering. After completing my graduation, I joined Cochin University of Science and Technology (CUSAT) for Master of Technology (M.Tech) in Atmospheric Sciences and passed with First Rank, where my research topic was on the “Anomalous behaviour of wet and dry spells of Indian Summer Monsoon Rainfall (ISMR)”. I am currently working towards hazard and risk mapping for the hydroclimatic extremes over India.

Recently, hydroclimatic extremes have become such evident and affected lives the whole way across the world. In this regard, understanding and monitoring the causalities and impacts of these extremes are also important. Thus, it is crucial to identify the factors and mechanisms that determine the location, intensity, and frequency of various hydroclimatic extremes, including floods, heavy precipitation, mass movement (wet), heat waves, droughts and wildfires. Many regions of the Indian subcontinent are becoming highly vulnerable to extreme heatwave events with adverse effects of temperature extremes on life and property. With this backdrop, the overall objective of the current research is to emphasize on mapping social vulnerability and risk to hydroclimatic extremes over India. An improved hazard map along with a precise social vulnerability map, can pave the way to generate a fine-scale risk map of heatwave events over India. You can find me in ESRL, second floor in the Environment Science and Engineering Department (ESED) at IIT Bombay.

I am currently working as an Institute Post Doctoral Fellow (IPDF) in the Environmental Science & Engineering Department (ESED) at the Indian Institute of Technology Bombay working with Prof. Subhankar Karmakar. I have completed my Ph.D. from the Department of Hydrology, Indian Institute of Technology Roorkee working with Prof. Manoj Kumar Jain and Dr. Rajendra Prasad Pandey. During my doctoral research, I was awarded with the prestigious Commonwealth Split-site Scholarship to undertake a part of my Ph.D. research objective at the School of Geography, Earth and Environmental Sciences, University of Birmingham working with Prof. David M. Hannah. I was the sole recipient of the 2023 David S. Miller Young Scientist Scholarship awarded by the American Geophysical Union (AGU). I have completed my M. Tech in Water Resources Engineering from the National Institute of Technology Silchar, and B.E. in Civil Engineering from the Priyadarshini College of Engineering, Nagpur.

I am currently working on Compound Drought and Heatwaves (CDHW) events over India. My Ph.D. thesis titled, “A Study on Drought Propagation in a Semi-Arid River Basin of Peninsular India,” examined how meteorological droughts evolve into hydrological droughts and their cascading impacts in data-scarce, semi-arid regions.

The performance of gridded datasets from 16 global precipitation products (gauge-interpolated, merged from various sources, re-analysis and satellite products) for the assessment of meteorological drought with reference to station datasets from India Meteorological Department (IMD) was evaluated at six drought zones over India. The analysis results showed that GPM-IMERG Final-Run outperformed all the other precipitation products for drought monitoring in most of the drought zones and in India as a whole. More details are available at Atmospheric Research, Gupta et al., 2023.

The changing characteristics of drought propagation and its propagation factor (PF) from meteorological to hydrological drought via agricultural drought was evaluated using an event-based approach in the Krishna River Basin of India. The propagation time of initiation, peak, and termination was analysed using two different cases: meteorological-to-agricultural (SPEI-to-SSMI) and agricultural-to-hydrological (SSMI-to-SSI) drought at multiple timescales and different drought threshold values. More details are available at Hydrological Processes, Gupta et al., 2024. While focused on the Krishna River Basin, the findings have broader implications for managing drought globally in other semi-arid river basins, aiding in drought risk assessment, early warning systems, and water resource management.

I am currently pursuing my Doctoral Degree in the IDP in Climate Studies from IIT Bombay and working with Prof. Subhankar Karmakar. I have completed my B.E. in Civil Engineering from Jadavpur University (Kolkata) and M.Tech in Civil Engineering from IIT Kharagpur.

I am currently involved in Flood Risk Forecasting. I am working towards the development of a web portal for the flood risk forecasting model for the entire India. I will consider the hazard and vulnerability drivers to evaluate the flood risk per the IPCC definition. The developed model will forecast any future flood event driven by extreme rainfall, and the flood risk hotspot regions can be identified easily. I have sound knowledge of flood risk and its evaluation, and I am interested in statistical programming and risk analysis. Further, I believe that more collaborative efforts and interdisciplinary ideas should always be welcomed for a better interpretation of the research problems and their solutions..

I am currently pursuing my doctoral degree in the Department of Environmental Science and Engineering at the Indian Institute of Technology Bombay. With a background in Environmental and Water Resources Engineering from the Indian Institute of Technology Hyderabad, my doctoral research focuses on advancing the understanding of flood generation processes and improving large-scale flood hazard and risk assessment. My broader interest lies in developing reliable hydrological and flood modelling frameworks that support effective disaster risk reduction.

Floods under changing climate conditions are increasingly uncertain, driven by complex interactions between hydrological and meteorological factors. My research contributes to deciphering these dynamics by identifying the primary flood-generating descriptors across India, providing insights into when, where, and why floods occur. Further details are available in Environmental Research Letters, Parmar et al., 2025.

Another major component of my research evaluates the strengths and limitations of Global Flood Models (GFMs), which simulate flood processes over large spatial scales. My study highlights that flood hazard estimates derived from GFMs are highly sensitive to the choice of runoff inputs, especially in densely populated regions. This has significant implications for exposure estimation and risk communication. A detailed assessment is presented in Environmental Research Letters, Parmar, Mohanty & Karmakar, 2025.

To address the substantial uncertainty arising from runoff-forcing variability in GFMs, I developed a multi-scenario, uncertainty-accounted flood hazard and exposure framework. This national-scale modelling framework integrates multiple runoff forcings in the CaMa-Flood model to generate optimistic, best-case, and conservative hazard and exposure scenarios for India. The framework directly applies frequency analysis to simulated flood depth, offering a scientifically transparent and scalable method for flood risk evaluation. This work is published in Science of the Total Environment (STOTEN), and the visualization of the work is available at this website.

I am currently an M.Sc.-Ph.D. student at the Indian Institute of Technology Bombay, in the Department of Environment Science and Engineering (ESED), since 2019. I am working with Prof. Subhankar Karmakar on the ‘First Assessment of Compound Risk from Tropical Cyclones over India’. In 2018, I graduated from Anugrah Narayan College, Patna, with a Bachelor of Science degree in Environment and Water Management. I got qualified in IIT JAM Mathematics with AIR56 and got admission in M.Sc.-Ph.D. dual degree in Environment Science and Engineering at IIT Bombay. For my master’s thesis, I have worked in the hydro-meteorology/climatology domain, exploring the multihazard/multivariate aspects of hydroclimatic/hydro-meteorologic extreme events to consider excess additional risk from compounding.

Simultaneous or successive extremes weaken emergency response systems at the local to the national level and reduce the resilience of natural and human infrastructure systems, leading to “loss amplification”. India is the worst affected region of the world by tropical cyclones, which are inherently compound/multivariate in nature. I am working to develop a first-ever comprehensive state-of-the-art framework of compound risk to tropical cyclones over India following IPCC AR6 (2022) guidelines. This compound risk map will facilitate identifying optimal mitigation and adaptation strategies for sustainable development (e.g., coastal flood management) in India.

A Ph.D. is a degree that not only allows achieving the designation of Doctor but also a way to serve society through helpful research. I am an M.Sc. – Ph.D. student currently working on the topic ‘Nationwide Coastal Flood Hazard Assessment’ under the supervision of Prof. Subhanakar Karmakar. I have completed my B.Sc. (Hons) in Chemistry from Banaras Hindu University, Varanasi.

According to the IPCC, hazard is one of the major components of risk. Flood hazards can be calculated using different methods, one of which is the empirical method. The empirical method includes statistical methods, machine learning/AI, as well as Multi-Criteria Decision- Making (MCDM) methods. In MCDM, hazard values are calculated using the flood drivers, which are often quantified as indicators. Coastal floods are the result of multiple drivers; therefore, calculating the flood hazard based on a single driver can underestimate the actual flood hazard. The indicator-based method enables the consideration of multiple drivers. The result maps obtained using this method can be utilized by policymakers and stakeholders to make better decisions on flood mitigation strategies and optimize resource allocation.

I am a PhD researcher who specialises in hydrogeomorphic methods for mapping flood susceptibility. My work focuses on understanding how geomorphology, topography, and hydrological processes interact to shape flood behaviour. I analyse terrain features, watershed shapes, and flood dynamics to see how landforms impact flood risk and management options.

My research aims to improve methods for assessing flood risk based on data and physical principles. This will help identify areas most at risk of flooding due to geomorphology. Through this work, I support the development of sustainable flood management strategies that help communities and decision-makers prepare for future flood risks. My flair for geography during my school days laid the foundation of Geography as a major for my Bachelor of Science and Master of Science as well as Master of Technology in Geoinformatics. In 2020, I graduated from Aliah University, Kolkata with 5 Year Integrated B.Sc-M.Sc in Geography. After that, I also graduated from University of Madras, Chennai with a degree of M.Tech in Geoinformatics in the Year 2022, June.

Resilience is the silent companion of every PhD journey. While the heart is busy learning to navigate uncertainty in the world of discovery and explore real-world problems, we undergo a quiet transformation—one that brings out our strongest, most thoughtful selves. I completed my BS-MS dual degree in Geology in July 2023 from the Department of Earth and Environmental Sciences at the Indian Institute of Science Education and Research (IISER) Bhopal. My master's research focused on quantifying the Suspended Sediment Dynamics and Morphological Impacts due to increased anthropogenic activities in the Narmada River of India. This work combined core principles of fluvial geomorphology with geospatial and statistical analysis and was carried out in collaboration between IISER Bhopal, India and Newcastle University, United Kingdom.

Currently, I am pursuing my doctoral degree in the Environmental Systems Research Laboratory (ESRL) of the Department of Environmental Science and Engineering (ESED) at the Indian Institute of Technology Bombay, under the supervision of Professor Subhankar Karmakar. My research is motivated by the increasing flood risks highlighted in the Intergovernmental Panel on Climate Change (IPCC)’s Sixth Assessment Report (AR6), especially in a flood-prone, agro-based country like India. In today’s rapidly urbanising and climate-challenged world, “living with floods”—rather than simply resisting them—has emerged as a critical paradigm shift, exposing the limitations of traditional flood-control strategies. Given this evolving landscape of risk, quantifying and operationalising flood resilience has become essential. Despite increasing global emphasis, India lacks comprehensive assessments of flood resilience. Building on the recommendations by Patra and Karmakar (2024), presented at the 8th Indian Water Week in New Delhi, my doctoral work aims to develop an integrated framework for quantifying and spatially mapping flood resilience across vulnerable regions.

My research interests broadly revolve around the intersection of geospatial analysis, flood hydrology, and numerical modelling, with a focus on understanding anthropogenic impacts on Earth’s natural resources and designing simple, scalable solutions to support communities vulnerable to flood hazards.