Hansi K. A. Singh
Atmospheric & Climate Dynamics
Computational Science
About Me

I received my PhD at the University of Washington in the Department of Atmospheric Sciences (defense date of July 17, 2015). I was advised by Professor Cecilia Bitz, who recently testified at a Senate hearing on how climate change is affecting the Arctic.


I was a US Department of Energy Computational Science Graduate Fellow (2011-2015).

I am currently a Linus Pauling Distinguished Postdoctoral Fellow at Pacific Northwest National Lab, sponsored by the US Department of Energy Office of Science. I am working with Phil Rasch, Ruby Leung, Jian Lu, and others on understanding how coupled atmosphere-ocean dynamics impacts the sensitivity of the polar regions to forcings. For further details, please see my statement of proposed research.

Education

Research Interests

My primary interest is in coupled climate dynamics, particularly that of the high latitudes. I am working to develop new frameworks, tools, and analysis methods for evaluating ocean-atmosphere-ice coupling processes and their effect on the climate system perturbation response to forcings, both anthropogenic and natural. I seek to understand polar climate change in the context of coupled dynamics and large-scale processes.


Following my PhD, I worked for a short time as a postdoctoral researcher with Greg Hakim. I investigated multidecadal time scale variability in the Last Millennial Reconstruction, a novel proxy reanalysis product in development by the Hakim group and others.


My dissertation work focused on the transport of water in the atmosphere, from its point of evaporation (or sublimation) to its point of precipitation. I studied aerial water transport using the Community Earth System Model, developed jointly by the National Center for Atmospheric Research (NCAR) and the US Department of Energy (DOE). I worked with a branch of the model with numerical water tracers, developed by Jesse Nusbaumer and David C. Noone (at the University of Colorado, Boulder).


I have also considered the role of atmosphere-ocean coupling in shaping the global climate response to the flattening of the Antarctic Ice Sheet (AIS). Surprisingly, the ocean is capable of mediating the most far-reaching climate responses to AIS flattening: in a fully-coupled model, the strongest response to AIS flattening is cooling over the Arctic! This response is completely absent when a slab-ocean is used rather than a fully dynamic ocean model.


My PhD qualifying work involved creating a heuristic model of the Dansgaard-Oeschger cycles, a series of abrupt climate change events that occurred during the last Ice Age. Their etiology is still a subject of considerable debate.