Representatives from ASU BIOS Travel to NASA

Field researchers share insights at annual PACE meeting, strengthening global efforts to monitor ocean health and climate change

By Lauren Kittell-Porter

In February 2024, NASA launched the PACE (Plankton, Aerosol, Cloud, ocean-Ecosystem) satellite, to better track Earth’s ocean and atmospheric health with more advanced ocean color sensors than ever before. To ensure its measurements are accurate, NASA enlisted global scientists, including two teams from ASU BIOS, as part of the PACE Validation Science Teams (PVSTs).

Despite Bermuda’s signature clear and low-nutrient water, factors like wind, stirred-up sediments, and pollutants can affect how light reflects off the ocean and returns to the satellite’s sensors. Ceridwyn Hunter, from the PACE Sargasso Sea Team (PVST_PSST) with principal investigator Eric Hochberg, contributes radiometry data that helps to account for these variables. The team uses an in-water sensor called a HyperPro that is deployed off the back deck during BATS cruises. Connected via fiber optic cables, it transmits light intensity data at varying depths as it descends through the water column. 

Other factors, such as clouds and particles in the atmosphere, known as aerosols, can also influence PACE’s estimates. To capture the effects of these variables, the team also utilizes an instrument mounted on the bow of the R/V Atlantic Explorer, the DALEC. “[The DALEC] measures incoming sunlight, atmospheric light scattering, and light reflected from the ocean surface,” explains Hunter. 

The light measured by the satellite also reflects off the tiny photosynthetic organisms in the water, whose primary productivity is one of the key values NASA hopes to measure with the new instrument. Second-year PhD student, Lauren Kittell-Porter, researcher and member of PVST - Plankton, led by Amy Maas, Rodney Johnson, and Leocadio Blanco-Bercial collects monthly ocean data alongside the Bermuda Atlantic Time-series Study (BATS) team to estimate plankton pigment concentrations, overall abundance, and particle sizes. This not only feeds the PACE project but also expands the scope of the BATS time series to include plankton imaging data.

Collaborative Science Enhances Climate Monitoring

The overall role of PVST is to determine the actual values of phytoplankton fluorescence, abundance, color, and diversity under varying light, cloud, and aerosol conditions, thereby improving the way PACE translates its observations. This takes a village!

Earlier this year, Lauren and Ceridwyn traveled to the NASA Goddard Institute for Space Studies in New York for the annual PACE Science Team meeting to better connect each team's work and find areas of improvement and potential streamlining in our protocols. They shared their progress, learned from researchers tackling similar challenges, and helped to shape the future of this satellite validation work.

“The meeting was my first in-person interaction with other members of PVST and NASA…In addition to forming new connections within the community, I received advice and support regarding sensor-specific questions, data processing, and more,” said Hunter.

Showcasing their preliminary results, Lauren and Ceridwyn received feedback from other teams to improve future protocols and expedite the timeline between sample collection and data sharing. This presented an opportunity not only to discuss their roles within the PACE project but also to showcase the capabilities of ASU BIOS, the BATS team, and the R/V Atlantic Explorer, and to explore potential overlaps with scientists from around the world.

The validation effort is ongoing through December 2027. Once complete, it will enable more accurate Earth measurements from space and a comprehensive long-term assessment of ocean color and plankton community shifts throughout the year, providing a robust system for monitoring ocean health and climate change impacts globally. This data will provide resource managers with access to ongoing satellite data that can help predict events such as harmful algal blooms, estimate the health of lakes and oceans, monitor water and air quality, and create projections for the future of their target ecosystems.

Interested in using PACE data? Check out the PACE Applications page: https://pace.oceansciences.org/applications.htm