Geologic sources of carbonaceous gasses and their impacts on terrestrial ecology

NASA Postdoctoral Program (NPP)

The NASA Postdoctoral Program offers unique research opportunities to highly‑talented scientists to engage in ongoing NASA research projects at a NASA Center, NASA Headquarters, or at a NASA‑affiliated research institute. These one‑to‑three‑year fellowships are competitive and are designed to advance NASA’s missions in space science, Earth science, aeronautics, space operations, exploration systems, and astrobiology.

Project Description

Geologic sources of carbon dioxide (CO₂) and methane (CH₄) to the atmosphere are important components of the Earth System, with direct atmospheric impacts and indirect feedbacks to local ecology and global carbon cycling. Geologic emissions of CO₂ and CH₄ occur naturally and are also directly and indirectly affected by human activities, e.g., resource extraction. Detection and accurate quantification of geologic CO₂ and CH₄ emissions on large scales are challenged by remoteness of emission sites, inaccurate attribution of emission sources, emission variability, and insufficient monitoring. These challenges amount to large uncertainties in the global budgets of geologic CO₂ and especially CH₄ emissions, with estimates for the latter ranging between 1.6 and 63 Tg per year, a factor of 40. A new cadre of satellite and airborne remote sensing platforms, termed “plume imagers,” is demonstrating increasing ability to detect geologic emissions of CH₄ and CO₂ emissions from space. Unlike “area mappers,” such as TROMOPI, GOSAT, OCO‑2 and ‑3, MethaneSat, and others, plume imagers sacrifice observation precision in gas concentration to greatly improve spatial resolution, enabling geolocation of emission on scales relevant to source attribution. Spaceborne plume imagers of note are the commercial GHGSat platform(s), the Carbon Mapper Coalition’s instrument onboard Planet’s Tanager‑1, and NASA’s EMIT imaging spectrometer on the International Space Station (ISS). GHGSat has demonstrated the ability to observe CH₄ point source emissions from geologic sources in Indonesia and Africa. With similar or better spectrometer specifications, NASA’s EMIT spectrometer, and the Carbon Mapper instrument are expected to share this capability, though this remains understudied. Sensitivity and resolution are enhanced further with the Airborne Visibile/Infrared Imaging Spectrometer (AVIRIS)‑class instruments, albeit with the coverage limitations inherent to airborne surveys. AVIRIS‑classic, AVIRIS‑NG, and AVIRIS‑3 have all demonstrated the capability for precise plume imaging of both CO₂ and CH₄.

This project seeks to synthesize available plume imaging datasets to address scientific problems related to quantifying CO₂ and CH₄ from natural hotspot sources (e.g., geologic vents, wetlands, etc.) and the feedbacks they impart to local ecology and potentially global greenhouse gas budgets. A major advantage of plume imagers is that many of them are hyperspectral and cover a broad range of VSWIR wavelengths, enabling detailed investigations of surface reflectance in the same spectra used to retrieve gas enhancements. We seek candidates with backgrounds in Earth and environmental science, especially those with experience using remote sensing data to study ecological phenomena. Backgrounds in atmospheric modelling of trace gas emissions are also considered a strength. We encourage research proposals to explore questions around the use of plume imaging technology to geolocate and quantify natural emissions of CH₄ and CO₂ and their potential feedbacks to local, regional, and potentially global systems.

Field of Science

Earth Science

Advisors

Clayton Elder
clayton.d.elder@nasa.gov
(650) 582-6105
Florian Schwandner
florian.m.schwandner@nasa.gov
(650) 604-3408

Eligibility

Applications with citizens from Designated Countries will not be accepted at this time, unless they are Legal Permanent Residents of the United States. A complete list of Designated Countries can be found at: https://www.nasa.gov/oiir/export-control.

Eligibility is currently open to:

• U.S. Citizens
• U.S. Lawful Permanent Residents (LPR)
• Foreign Nationals eligible for an Exchange Visitor J‑1 visa status
• Applicants for LPR, asylees, or refugees in the U.S. at the time of application with 1) a valid EAD card and 2) I‑485 or I‑589 forms in pending status

Qualifications

A doctoral degree in the Earth and environmental sciences (e.g., Earth System Science, Atmospheric Science, Geography, etc.) or closely related field is required. Expertise in remote sensing, greenhouse gas observations and/or modeling, and use of large datasets will be considered strengths.

Point of Contact

Mikeala

References

• Saunois, M., et al., 2024. Global methane budget 2000–2020. Earth System Science Data Discussions, 2024, pp.1-147.
• Mazzini, A., et al., 202