Dr. DeWitt was an MIT CGCS Research Scientist from early 2015 to early 2018 where she held the role of Station Chief Scientist for the Rwanda Climate Observatory. She is an analytical chemist with a specialty in mass spectrometry and a focus on the analysis of aerosols (particles or liquid suspended in air (e.g., smog; dust; sea salt), from laboratory-simulated aerosol mimicking those potentially present on the Archean Earth and Titan to in-situ aerosol sampled in remote marine locations to anthropogenically-influenced aerosol sampled adjacent to a major highway.