NASA, NOAA analyses reveal record-shattering global warm temperatures in 2015. Posted Jan. 20, 2016,

Atmospheric Sciences

Chanh Kieu, Cody Kirkpatrick, Paul Staten

Atmospheric Sciences at Indiana University is a dynamic program with exciting opportunities to undertake field, satellite, or modeling research. Our faculty members actively conduct both observational and modeling studies of weather and climate processes across scales, from cold fronts and tropical cyclones, to global atmospheric cloud and circulation patterns.

The Atmospheric Sciences Group is an active participant in the interdisciplinary research of other Earth and Atmospheric Sciences faculty, including paleoclimate research and global climate change studies.

The Department’s diverse, close-knit group of researchers enjoys a collective expertise in atmosphere-hydrosphere-solid Earth interactions. We are among the most active users of IU’s high-performance parallel computing facilities which include the new Big Red II machine - one of the world’s 70 fastest supercomputers.


Simon Brassell

Simon Brassell

Professor of Geological Sciences

Simon's research activities continue to be focused on the use of the molecular and isotopic compositions of sediments to elucidate paleoclimates and paleoenvironments, and to study the fate of organic matter in the geosphere. Recent investigations by Devon Colcord as part of her M.S. and Ph.D. studies have included assessment of climate records in lake sediments from Greenland, studying cores collected by the GetGamm program led by Lisa Pratt. Two publications in Organic Geochemistry have verified that the distributions of molecules biosynthesized by bacteria known as branched GDGTs (glycerol dialkyl glycerol tetraethers) include contributions from autochthonous sources within lakes augmenting their origin from surrounding soils, and confirmed this conclusion by the first direct measurement of the carbon isotope composition of these molecules in collaboration with Professor Ann Pearson at Harvard University. Another recent publication in Organic Geochemistry reports the results from the M.S. thesis of Amishi Kumar, who elucidated the separate contributions of polycyclic aromatic hydrocarbons originating from both natural and anthropogenic sources of both petrogenic and pyrolytic compounds within sediments from the Santa Barbara Basin, offshore California.

Over the past couple of years, investigations led by Ph.D. students Devon Colcord and Andi Shilling are elucidating changes in climate recorded by biogeochemical indices in a series of early Pleistocene lacustrine sediment cores recovered from Olduvai Gorge. This research is part of a larger collaborative project led by Jackson Njau, Nick Toth, and Kathy Schick that aims to explore environmental change during critical intervals of hominin evolution established at Olduvai. The laminated sediment sequence from ~1.8 Ma provides an extraordinary opportunity to determine short-term changes in climate that triggered responses in the lake phytoplankton and surrounding vegetation at a time of high hominin diversity.

Simon continues to work on profiling ancient climates and is a co-author of a recent paper focused on a comprehensive collation of temperature records for the Cretaceous, which has been published in Earth Science Reviews. He is also collaborating with Arndt Schimmelmann and Maria Mastalerz in analysis to better understanding the specific nature of catalytic processes transforming organic matter during diagenesis in the New Albany and other shales.

Simon teaches both a fully online introductory oceanography course that utilizes web-based resources in student exercises exploring a wide range of oceanographic phenomena and a College critical approaches class on records of global climate change.

Erika R. Elswick

Erika Elswick

Senior Lecturer and Director, Analytical Geochemistry Laboratory

Fall 2017 has brought a lot of additional activity to the Analytical Geochemistry Laboratory with a full class in Methods in Analytical Geochemistry (G444/G544). In the spring we acquired a new ion chromatograph for the analysis of anions in water samples. The new Thermo/Dionex instrument replaces a much older unit, and is very student friendly. We continue to analyze aqueous solutions and solids for departmental members, as well as colleagues in other departments and units across campus.

During the summer of 2017 I embarked on a new project with a colleague to begin to instrument a wetland located in the National Forest land above the IU Field Station associated with the late 19th and early 20th Century mining activities. We ultimately hope to shed some light on this dynamic setting to develop models for remediation at higher altitudes.

Arndt Schimmelmann

Senior Scientist, Organic Geochemistry and Chemical Oceanography

Arndt Schimmelmann’s international team of scientists from Vietnam, Germany, and Indiana University identified subterranean microbes in caves to voraciously consume the strong greenhouse trace gas methane from air. Cave air typically exchanges with the atmosphere on short time scales. Methane depletion in cave air on several continents indicates that the subterranean microbial sink for methane is substantial enough to warrant inclusion in global greenhouse gas modeling. In contrast, laboratory experiments at Indiana University with strong radiation from radon isotopes excluded the possibility that elevated natural radioactivity in caves can significantly contribute to oxidation of methane in air. Furthermore, Schimmelmann’s team continues to develop remediation strategies to mitigate radiation geohazards in mud-built homes in developing countries (see website: Outreach activities in mountain villages established personal contacts and reliable logistic support for our research.

As a third collaborative research project with Vietnam National University in Hanoi, the laminated sediment from a volcanic maar lake in central Vietnam near Pleiku is being explored as a geological archive for prehistorical monsoon strength. The record of distinct flood layers of the past can be radiocarbon-dated and may offer a reliable statistical basis to judge the effects of climate change on modern precipitation patterns in central Vietnam.

Laura Wasylenki

Associate Professor, Geological Sciences, Biogeochemistry of metals

Laura Wasylenki was on sabbatical in 2016-17, spending seven months at Stanford University and three months at École Polytechnique Fédérale de Lausanne in Switzerland. She is investigating mineral-fluid reactions that attenuate the migration of toxic heavy metals in soils and near-surface groundwater. At the Stanford Synchrotron Radiation Lightsource, she shone bright beams of X-rays onto samples of iron and manganese oxyhydroxide particles that she had loaded with small amounts of tungsten, a likely carcinogen that has been widely introduced to the environment during weapons production and testing. She is studying the molecular-scale mechanisms by which adsorption to common soil particles can immobilize this toxic metal. She plans to test some of the new knowledge derived in the laboratory on a tungsten-contaminated field site in South West Indiana with new graduate student Coley Smith. In Switzerland, Wasylenki began a collaboration with an environmental microbiology group interested in molecular-scale mechanisms of uranium immobilization. While in Switzerland, she also made time to observe with great joy plenty of steeply dipping Jurassic carbonates adorned with Late Holocene glaciers and was joined on one occasion by former student Michael Haluska, M.S. ’15.