This is a past event.

Environmental Engineering Graduate Seminar

Tirthankar "TC" Chakraborty, Earth Scientist, Earth System Modeling Group, Atmospheric Science & Global Change Division, Pacific Northwest National Laboratory

Examining Urban Heat Across Scales: From Observations to Model Simulations

Abstract: Cities have higher temperatures compared to their background climate. Depending on scale, this urban warming can have public health consequences, prompting the need for urban-scale heat mitigation strategies. Cities are also heterogeneous, leading to spatial variability in heat exposure, with warmer areas often coinciding with disadvantaged neighborhoods, particularly seen for U.S. cities. In this talk, I will give an overview of previous work on urban warming impact at multiple scales (global, regional, to city) and using various methods (satellite observations, in situ measurements, and numerical models). Additionally, I will discuss distributional inequality in urban heat exposure within cities. Finally, I will elaborate on some major sources of uncertainties in both measured and modeled estimates of the urban warming signal. One such critical topic is the variability of surface temperature versus air temperature versus moist heat stress within urban areas and their urban-rural differences across cities. Another will be on uncertainties in urban representation in models. The talk will summarize the lessons learned from multiple past studies to guide future urban climate research and provide some recommendations on how to get more actionable quantitative estimates to inform policy. 

Bio: Dr. Tirthankar Chakraborty (goes by TC) is an Earth Scientist at the Pacific Northwest National Laboratory (PNNL) with interest in atmosphere-biosphere interactions at various scales. He is currently working on improving urban representation in land models and examining extreme events (heatwaves and extreme precipitation) over coastal cities. In the past, he has worked extensively on urbanization-induced warming and its within-city disparities by leveraging satellite measurements, crowdsourced weather station data, and conceptual modeling frameworks. He is also interested in the role of big data, machine learning, and urban informatics to better understand cities and their complexities. Before joining PNNL, TC finished his PhD from Yale University on developing a surface-energy budget perspective on aerosol-climate interactions. He often uses the Google Earth Engine (GEE) cloud computing platform for geospatial analysis and was one of 26 inaugural GEE Developer Experts in the world. TC’s work has been featured in high impact scientific publications like Nature Communications and Science Advances as well as in popular media outlets like the New York Times and the Washington Post. He received the U.S. Department of Energy Early Career grant this year to improve urban representation in Earth system models through planetary-scale data-model integration.