Research

Polar ENV is planetary agnostic and utilizes a variety of geochemical techniques to explore critical cryosphere interfaces. Our core research primarily focuses on the geochemistry of ice-covered and periglacial environments in the Arctic and Antarctic. We are particularly interested in research within the following themes:

(Bio)geochemical cycling and chemical evolution at sediment-ice and water-ice interfaces in resource-limited systems.
Influence of aeolian material deposition and chemical weathering on ecosystem development and habitat suitability
Fidelity of Earth-based analogs in the Arctic and Antarctic for current and ancient ice-covered systems.
Capture of geochemical and isotopic signatures of underlying water chemistry, sediments, and seafloor processes in ice.
Biogeochemical cycle perturbations due to climate-change and other anthropogenic influences.
The ways in which natural systems, urban geochemistry, and equity intersect.
Weaving science, storytelling, and art to broaden participation in the geosciences.

Current projects as PI or Co-PI

McMurdo Dry Valleys LTER

The McMurdo Dry Valleys Long Term Ecological Research project is an interdisciplinary study of the aquatic and terrestrial ecosystems in a cold desert region of Antarctica. In 1992, this area was selected as a study site within the NSF's Long-term Ecological Research (LTER) Program. Details about the research can be reviewed through the original research proposal to NSF, or the most recent 2022 proposal, resulting in funding for another 6 years, at https://mcm.lternet.edu/. This unique site will help us understand ecosystem response to changes in physical drivers on Earth, and possibly for other hyper-arid environments (e.g., Mars).
NSF OPP 2224760; PI Michael Gooseff (CU Boulder)

Ice-marginal lake biogeochemistry

Lake Tininnilik is a large ice-marginal lake restrained by an ice dam along Sarqardliup Glacier in western Greenland. It drains approximately every 10 years into a local fjord, most recently in 2025, discharging vast amounts of meltwater to the ocean. Our research has shown that glacier outburst floods are a large and previously unaccounted source of biogeochemically important elements to nutrient-limited ocean waters. The resulting perturbations to coastal carbon cycling negatively affect local fish catch. Beyond the Arctic, this work will be applied towards understanding large- and small-scale landscape response to climate transitions on Earth and other planetary bodies (e.g., Laurentide ice sheet and paleo-Mars).
NSF OPP 2224824; PI Melisa Diaz (Ohio State)

Processes at ice-ocean interfaces

Sea ice plays an important role in regulating Earth’s energy balance, and polar ice ecosystems are among the largest on Earth. As sea ice forms, brine pockets and channels are created that may extend through much of its thickness. These channels are known hotspots for biogeochemical cycling. Our study is developing a novel approach to correcting remotely sensed freeboard data from ICESat-2 and coupling those measurements to sea ice biogeochemical cycling. The results will improve sea ice thickness data products and identify important conditions primed for (astro)biology. Our approach can be extrapolated to other ice-covered regions on Earth and icy Ocean Worlds (e.g., Europa and Enceladus).
NASA IDS 80NSSC24K0725; PI Melisa Diaz (Ohio State)

Ice-covered methane lakes

Life on Earth can often be found at the boundary between two physical layers, as energy exchange often occurs at these sites. On Ocean Worlds, like Europa, Enceladus, and Titan, the ice-water interface may be rich with materials from the ocean below and with compounds delivered from the ice above, thus providing a potentially habitable interface. Through this project, we will study the ice-water interface of an Arctic thermokarst lake with active geologic methane seeps, in which materials are trapped at the interface during the fall/winter freeze-over period. Geochemical analysis of this system will determine how isotopes and compounds incorporated in the ice reflect reducing conditions in the sediments.
NASA PSTAR RSA No. 1717835; PI Kevin Hand (NASA JPL)

Dust weathering on glaciers

Despite low temperatures and the relative scarcity of liquid water, glacial systems can be a major source of trace metals, nutrients and other weathering products to proglacial and marine systems. Little is understood about weathering mechanisms or the composition of major and trace nutrients in snow and supraglacial ice. This research will combine computer modeling and laboratory experiments to understand 1) what happens (chemically and physically) to glacier and snowpack dust during freezing and thawing and 2) how to model freezing and thawing of water and dust in glacier ice.
NSF OPP 2148067; PI Melisa Diaz (Ohio State)

Metal Redlining Network

The Metal Redlining Network's central goal is to build a cross-city network that empowers research, education, and policy advocacy to advance Geohealth equity. We collaborate around a shared research question: Has redlining resulted in an unjust soil metal burden? Redlining is the systemic disinvestment in communities based on race, class, or other factors. We seek to answer our research question by examining metal pollution associated with the "Residential security zones" established by the Home Owner Loan Corporation prior to the 1950s. Learn more at: https://serc.carleton.edu/earthconnections/networks/metal_redlining/index.html

Girls* on Rock

Girls* On Rock (GOR) is a pre-college Geoscience Learning Ecosystem (GLE) consisting of a backcountry expedition followed by ongoing cohort and career development activities. The program is designed for diverse youth 16-17 years old identifying as girls* (cis or trans) or nonbinary from backgrounds that are historically underrepresented in the Geosciences to explore the geologic and cultural history of the Rocky Mountains by interweaving scientific research, with artistic expression and physical challenges, such as rock climbing and backcountry exploration. GOR is a member of the Inspiring Girls* Expeditions (IGE) network.
NSF RISE 2325683 PI Melisa Diaz (Ohio State) -- grant terminated Spring 2025