Rate My Professor Karen Johannesson

Karen Johannesson is a Professor of Geochemistry in the School for the Environment at the University of Massachusetts Boston, where she also directs the Environmental Analytical Core Facility and participates in the Intercampus Marine Sciences Graduate Program. She earned her PhD in Hydrology and Hydrogeology from the Mackay School of Mines at the University of Nevada, MS in Geology and Geophysics from Boston College, and BS in Geology from the University of New Hampshire. From 2007 to 2019, she served as Professor of Geochemistry and Chemical Hydrogeology at Tulane University, holding the Cochran Family Professorship in Earth and Environmental Sciences from 2015 to 2019. Her research centers on environmental geochemistry, with a focus on the chemical speciation and biogeochemical cycling of trace elements, particularly rare earth elements, in groundwater flow systems, as well as estuarine and coastal marine environments. Johannesson examines how microbial processes affect trace element mobilization and transport through innovative field studies, state-of-the-art analytical methods, and numerical models simulating microbial respiration, chemical speciation, and reactive solute transport.

Johannesson has published over 130 peer-reviewed scientific papers and 11 peer-reviewed book chapters. She edited the seminal book Rare Earth Elements in Groundwater Flow Systems, published by Springer in 2005. Key publications include Speciation of rare earth elements in natural terrestrial waters: assessing the role of dissolved organic matter from the modeling approach (Geochimica et Cosmochimica Acta, 2003), Rare earth elements (REE) and yttrium in stream waters, stream sediments, and Fe–Mn oxyhydroxides: fractionation, speciation, and controls over REE+ Y patterns (Geochimica et Cosmochimica Acta, 2008), and Rare earth elements as geochemical tracers of regional groundwater mixing (Geochimica et Cosmochimica Acta, 1997). She holds prestigious editorial positions as Co-Editor-in-Chief of Chemical Geology since 2016 and Associate Editor of Geochimica et Cosmochimica Acta. Her groundbreaking contributions to the aqueous geochemistry of lanthanide series elements earned her the Clair C. Patterson Medal from the Geochemical Society in 2015. Johannesson is a Fellow of the American Geophysical Union (2024), Geochemical Society, European Association of Geochemistry, International Association of GeoChemistry, and Geological Society of America.