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Summary of the 2023 GEDI Science Team Meeting


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Summary of the 2023 GEDI Science Team Meeting

Introduction

The 2023 Global Ecosystem Dynamics Investigation (GEDI) Science Team Meeting (STM) took place October 17–19, 2023, at the University of Maryland, College Park (UMD), in College Park, MD. Upwards of 80 people participated in the hybrid meeting (around 50 in-person and the rest virtually). Included among them were GEDI Science Team (ST) members, collaborators, and stakeholders – see Photo. The primary goals of the meeting included providing a status update on the GEDI instrument aboard the International Space Station (ISS), receiving final project updates from the inaugural cohort of the GEDI completed ST, and understanding the present status and future goals of data product development.

After a short mission status update, the remainder of this article will summarize the content of the STM. For those desiring more information on these topics, some of the full meeting presentations are posted online. Readers can also contact the GEDI ST with specific questions.

GEDI group photo
Photo. GEDI Science Team Meeting in-person and virtual attendees.
Photo credit: Talia Schwelling

Mission Status Update: GEDI Given New Lease on Life

A lot has changed since the publication of the last GEDI STM summary. (See Summary of the GEDI Science Team Meeting in the July–August 2022 issue of The Earth Observer [Volume 34issue 4, pp. 20–24]). When the GEDI ST convened in November 2022, the fate of GEDI was hanging in the balance, with the plan being to release GEDI from the ISS at the end of its second extension period.

NASA saved the instrument, however, and a new plan went into effect: in order to extend its tenure on the ISS, the GEDI mission entered a temporary period of “hibernation” in March 2023 after nearly four years in orbit. This hibernation period and movement of the instrument from Exposed Facility Unit (EFU)-6 (operating location) to EFU-7 (storage location) made way for another mission – see Figure 1(UPDATE: After being in storage for roughly 13 months, the GEDI instrument was returned to its original location on the Japanese Experiment Module–Exposed Facility (JEM–EF) on Earth Day this year, April 22, 2024, and is now once again back to normal science operations using its three lasers.)

GEDI figure 2
Figure 1. NASA’s GEDI instrument was moved from EFU-6 to EFU-7 on the ISS on March 17, 2023, where it remained in hibernation for 13 months until its recent reinstallation to EFU-6 on April 22, 2024. The instrument is once again back to normal science operations using its three lasers.
Figure credit: NASA

As The Earth Observer reported in 2023, data from GEDI are being used for a wide range of applications, including biomass estimation, habitat characterization, and wildfire prediction (See page 4 of The Editor’s Corner in the March–April 2023 issue of The Earth Observer [Volume 35,Issue 2, pp. 1–4]. This section also reports on GEDI’s extension via out-of-cycle Senior Review in 2022). GEDI data is used to develop maps to quantify biomass that are unique in both their accuracy and their explicit characterization of uncertainty and are a key component in the estimation of aboveground carbon stocks, as absorbed carbon is used to drive plant growth and is stored as biomass – see Figure 2. These estimations help quantify the impacts of deforestation and subsequent regrowth on atmospheric carbon dioxide (CO2) concentration. NASA’s choice to extend the GEDI mission has significantly broadened the capacity to collect more of these important data.

GEDI figure 1
Figure 2. Country-wide estimates of total aboveground biomass in petagrams (Pg) using GEDI Level-4B Version 2.1 dataset (GEDI_L4B_AGB).
Figure credit: ORNL DAAC

DAY ONE

GEDI Mission Operations, Instrument Status, and Data Level Updates

Ralph Dubayah [UMD—GEDI Principal Investigator (PI)] opened the meeting with a summary of the current status of the mission and GEDI data products. After reviewing the details of GEDI’s hibernation (described in the previous section) he went on to describe what GEDI has accomplished over the past 4.5 years of operations, noting that the instrument collected over 26 billion footprints over the land surface.

All the data collected by GEDI during its first epoch (i.e., before its hibernation) have been processed and released to the appropriate Distributed Active Archives Centers (DAACs) as Version 2 (V2) products. (To learn more about the DAACs and other aspects of Earth Science data collection and processing, see Earth Science Data Operations: Acquiring, Distributing, and Delivering NASA Data for the Benefit of Society, in the March–April 2017 issue of The Earth Observer, [Volume 29, Issue 2, pp. 4–18]. The DAACs – including URL links to each – are listed in a Table on page 7–8 of this issue). The two DAACs directly involved with GEDI data processing are the Land Processes DAAC (LP DAAC) and Oak Ridge National Laboratory (ORNL) DAAC. The LP DAAC houses GEDI Level-1 (L1) data, which consists of geolocated waveforms, and L2 data, which is broken down into L2A and L2B. L2A data includes ground elevation, canopy height, and relative height metrics. (Waveform measurements are described in detail in a sidebar on page 32 of the Summary of the Second GEDI Science Team Meeting in the November–December 2016 issue of The Earth Observer [Volume 28, Issue 6, pp. 31–36].) L2B data includes canopy cover fraction (CCF) and leaf area index (LAI). The ORNL DAAC houses GEDI L3 gridded land surface metrics data, L4A footprint level aboveground biomass density data, and L4B gridded aboveground biomass density data – e.g., see Figure 2.

Dubayah went on to explain that while GEDI hibernated, the mission team would work to enhance existing data products as well as produce new products. Version 3 (V3) datasets for all data products are expected to be released by the fall of 2024, and new data products are in development, including a waveform structural complexity index (WSCI) and a topography and canopy height product that blends data from GEDI and the Ice, Clouds, and land Elevation Satellite–2 (ICESat–2) mission. A new dataset, the GEDI L4C footprint level waveform structural complexity index (WSCI) product, was added to the ORNL DAAC catalogue in May 2024. To further improve data quality and coverage, the GEDI team is hoping to organize an airborne lidar field campaign to southeast Asia in the coming years. Dubayah concluded his updates by highlighting a set of six papers published in 2023 in Nature and Science family or partner journals that focused on the use of GEDI data. Visit our website for a comprehensive list of publications related to GEDI.

After receiving a general update from the mission PI, the next several presentations gave meeting participants a more in-depth look at GEDI science data planning and individual data products. Scott Luthcke [NASA’s Goddard Space Flight Center (GSFC)—GEDI Co-Investigator (Co-I)] presented status updates for the GEDI Science Operating Center (SOC), including the Science Planning System (SPS) and Science Data Processing System (SDPS) automation, development, and processing. In addition, he reported on the status of the L1 geolocated waveform data product and the L3 gridded land surface metrics product. At the time of this meeting, the SPS had completed operations through mission week 223 – almost 4.5 years of data – and was beginning to transition to improving processes on the back end while GEDI hibernates. The SDPS had completed processing and delivery of all V2 data products to the LP DAAC and ORNL DAAC.

Luthcke reported on GEDI’s current observed and estimated geolocation performance, including detailed summaries of component analysis and steps towards improving Precision Orbit Determination (POD), Precision Attitude Determination (PAD), Pointing Calibration, time-tag correction, and Oven Controlled Crystal Oscillator (OCXO) calibration. GEDI passes over Salar de Uyuni, the world’s largest salt flat located in Bolivia – see Figure 3, are being used to assess the PAD high-frequency and low-frequency errors. Estimated errors are shown to be consistent with observed geolocation errors. Finally, Luthcke gave a summary of completed L3 products and new wall-to-wall 1-km (0.62-mi) resolution and high-resolution products.

GEDI figure 3
Figure 3. Salar de Uyuni, the world’s largest salt flat as seen from the International Space Station.
Figure credit: Samantha Cristoforetti/ESA/NASA

John Armston [UMD—GEDI Co-I] updated attendees on GEDI L2 products. L2A consists of elevation and height metrics, and L2B consists of canopy cover and vertical profile metrics. To assess GEDI ground and canopy top measurement accuracy and improve algorithm performance, the mission team is using data collected from NASA Land, Vegetation, and Ice Sensor (LVIS) campaigns from 2016 to present. Armston reported that L2B estimates of canopy and ground reflectance were completed for the first mission epoch (April 2019–March 2023) and the GEDI team continues to work on algorithm improvements for cover estimates in challenging conditions (e.g., steep slopes). Data users can expect improved waveform processing for ground elevation and canopy height, new reflectance estimation, and revised quality metrics and flags in the L2A and L2B not-yet-released V3 products.

Jim Kellner [Brown University—GEDI Co-I] shared the current status of and planned algorithm improvements to the L4A data product, or the footprint-level aboveground biomass density product. The algorithm theoretical basis document for L4A data products was published in November 2022; it describes how models were developed and the importance of quality filtering. L4A data product development continues in tandem with updates to L2A data and improvements to existing calibration and validation data and ingestion of new data.

Sean Healey [U.S. Forest Service—GEDI Co-I] reviewed coverage and uncertainties of the recently produced V2 L4B data products – see Figure 4. Ongoing GEDI-relevant research includes:

  • investigating a statistical method called bootstrapping, which may allow more complex types of models;
  • conducting theoretical statistical studies aimed at decomposing mean square error for model-based methods; and
  • developing ways to estimate biomass change over time – which will become more important as the extended mission potentially stretches to a decade.
GEDI figure 4
Figure 4. Gridded mean aboveground biomass density [top] and standard error of the mean [bottom] from Version 2.1 of the GEDI L4B Gridded Aboveground Biomass Density product, published on October 29, 2023.
Figure credit: ORNL DAAC

Competed Science Team Presentations—Session 1

This GEDI STM was the last convergence of the first iteration of the GEDI competed ST. Attendees received final in-person updates on the cohort’s projects and plans for future research. Over the course of the three-day meeting, there were several sections dedicated to Competed ST Presentations. For purposes of organization in this report, each section has been given a session number. 

Taejin Park [NASA’s Ames Research Center (ARC) and Bay Area Environmental Research Institute (BAERI)] kicked off the ST presentations with an overview of his group’s progress in enhancing the predictions of forest height and aboveground biomass by incorporating GEDI L2, L3, and L4 data products into a process-based model, called Allometric Scaling Resource Limitation (ASRL), over the contiguous United States (CONUS). The ASRL model effectively captures large-scale, maximum tree size distribution and facilitates prognostic applications for predicting future aboveground biomass changes under various climate scenarios. Park also described collaborative research efforts with international partners  to map changes in aboveground biomass in tropical and temperate forests using a carbon management systems (CMS).

Kerri Vierling [University of Idaho] shared the results from her team’s projects demonstrating the use of GEDI data fusion products to describe patterns of bird and mammal distributions in western U.S. forests. The focal species for these projects include a suite of vertebrate forest carnivores, prey, and ecosystem engineer species that modify their environments in ways that create habitat for other creatures, e.g., woodpeckers – see Figure 5. Many of these species are of interest for management by a variety of state and federal agencies. Vierling also discussed ongoing analyses identifying biodiversity hotspots and land ownership patterns.

GEDI figure 5
Figure 5. A Female downy woodpecker creates a tree cavity that other organisms may use in the future for habitat. Woodpecker species are great examples of ecosystem engineers.
Figure credit: Doug Swartz/Macaulay Library at the Cornell Lab or Ornithology (ML 58304661)

Sean Healey presented on his competed ST research on Online Biomass Inference using Waveforms and iNventory (OBI-WAN), a Google Earth Engine application. This forest-carbon reporting tool harnesses GEDI waveforms, biomass models, and statistics to make estimates of mean biomass and biomass change for areas specified by online users. Healey explained the statistical methods applied to operate OBI-WAN and gave context for the use of sensor fusion to provide biomass change information that is critical for monitoring, reporting, and verification.

Keith Krause [Battelle] presented his work evaluating vertical structural similarity of LVIS classic and GEDI large-footprint waveforms. At the GEDI and LVIS footprint scale (20–23 m, or 65–75 ft, spot on the ground), lidar waveforms over forests represent canopies of leaves and branches from several trees. Krause presented results comparing waveforms against each other to show similarities in shape (i.e., if the trees in their footprints have a similar vertical structure). He also described how he used data clustering techniques to group similar waveforms into distinct structural classes. From there, he could map waveforms with similar vertical structure to better understand the spatial distribution of the structural groups.

Breakout Sessions—Session 1

GEDI STMs offer a rare opportunity for members of the competed and mission STs, a variety of stakeholders, and other individuals to convene and discuss ideas and goals for their own research and for the GEDI mission. Toward that end, breakout sessions were held on the first and second day of the meeting – referred to as Session 1 and Session 2 in this report. The individual breakout meetings used a hybrid format allowing in-person and online participants to join the discussion that was most relevant to their interests and expertise.

Chris Hakkenberg [Northern Arizona University (NAU)] led a breakout session on structural diversity, including the horizontal and vertical components. Different structural attributes, (e.g., stand structure, height, cover, and vegetation density) have different – but related – metrics and measurement approaches. Participants discussed biodiversity-structure relationships (BSRs), how to better characterize horizontal structural diversity, and how to define which metrics (i.e., scale, sampling unit, and spatial resolution) are most meaningful in different situations.

Jim Kellner led a session that focused on biomass calibration and validation and how to create the best data products given global environmental variation. Special cases – e.g., mangroves – pose challenges for calibration and validation because they don’t always have as much plot-level data as other environments. Participants discussed how to determine strata while considering climactic and environmental covariates as well as constraints of data availability and consistency.

Competed Science Team Presentations—Session 2

The FORest Carbon Estimation (FORCE) Project is exploring the use of GEDI-derived canopy structure metrics to map forest biomass in the U.S. and Canada. Daniel Hayes [University of Maine] presented comparisons of GEDI metrics and canopy height models derived from airborne lidar and photo point clouds over different forest types and disturbance history in managed forests of Maine. Co-PI Andy Finley [Michigan State University] presented new work that adjusts GEDI L4B biomass estimates to plot data over the continental U.S. from Forest Inventory and Analysis (FIA) program of the U.S. Department of Agriculture’s Forest Research and Development Branch. The project’s next steps are to fuse GEDI canopy structure metrics with other covariates in a spatial model to produce wall-to-wall estimates of biomass for boreal–temperate transition forests in northeast North America.

GEDI data is also being used to study tropical forests. Chris Doughty [NAU] described how he and his team analyzed GEDI L2A data across all tropical forests and found that tropical forest structure was less stratified and more exposed to sunlight than previously thought. Most tropical forests (80% of the Amazon and 70% of southeast Asia and the Congo Basin) have a peak in the number of leaves at 15 m (49 ft) instead of at the canopy top. Doughty and his team have found that deviation from more ideal conditions (i.e., lower fertility or higher temperatures) lead to shorter, less-stratified tropical forests with lower biomass.

Paul Moorcroft [Harvard University] reported on studies of current and future carbon dynamics across the Pacific Coast region based on forest structure and rates of carbon uptake. Moorcroft’s group examined how these ecosystems will behave in the future under different climate scenarios and have plans to conduct similar studies in other regions.

DAY TWO

Naikoa Aguilar-Amuchastegui [World Bank] kicked off day two with his perspective on the importance of streamlining the monitoring, reporting, and validation (MRV) process from scientific estimation to actual use of the data. Once scientific data is generated, end users are often faced with challenges related to transparency and understandability. Scientists can better communicate how to use their datasets properly, by familiarizing themselves with who wants to use their data, why they want to use it, and what their needs are. With this information in mind, data can be presented in more practical ways that allow for a variety of institutions with different standards and frameworks to integrate GEDI data more easily into their reporting. As the GEDI team continues to produce high-quality maps, efforts are underway to connect with end users and provide tutorials, workshops, and other resources.

GEDI Demonstrative Products

Demonstrative products show how GEDI data can be used in practice and in combination with other resources. Ecosystem modeling is one way that GEDI data are being used to address questions about aboveground carbon balance, future atmospheric CO2 concentrations, and habitat quality and biodiversity. George Hurtt [UMD—GEDI Co-I] shared his progress on integrating GEDI canopy height measurements with the Ecosystem Demography model to estimate current global forest carbon stocks and project future sequestration gaps under climate change – see Figure 6. Hurtt emphasized that this unprecedented volume of lidar data significantly enhances the ability of carbon models to capture spatial heterogeneity of forest carbon dynamics at 1 km (0.6 mi) scale, which is crucial for local policymaking regarding climate mitigation.

GEDI figure 6
Figure 6. [Top] Average lidar canopy height at 0.01° resolution, computed by gridding both GEDI and ICESat-2 together, and carbon stocks [middle] and fluxes [bottom] from ED-Lidar (GEDI and ICESat-2 combined). The insets highlight fine-scale spatial distribution and coverage gaps at selected regions (1.5° × 1.5°). Note that the three maps show grid-cell averages aggregated from sub-grid scale heterogeneity for each variable.
Figure credit: From a 2023 article in Global Change Biology.

There is also great potential for the development and application of methods for mapping forest structure, carbon stocks, and their changes by fusing data from GEDI and the Deutsches Zentrum für Luft- und Raumfahrt’s (DLR) [German Space Operations Center] TerraSAR-X Add-oN for Digital Elevation Measurement (TanDEM-X) satellite mission, which uses synthetic aperture radar (SAR) to gather three-dimensional (3D) images of Earth’s surface. This fusion product is being spearheaded by Wenlu Qi [UMD], who presented on efforts to create maps of pantropical canopy height, biomass, forest structure, and biomass change using the fusion product as well as maps of forests in temperate U.S. and Hawaii.

Data from the GEDI mission are also being used to quantify the spatial and temporal distribution of habitat structure, which influences habitat quality and biodiversity. Scott Goetz [NAU—GEDI Deputy PI] presented on biodiversity-related activities, citing a 2023 paper in Nature that examined the effectiveness of protected areas (PAs) across southeast Asia using GEDI data to compare canopy structure within and outside of PAs – see Figure 7. He also presented an analysis of tree and plant diversity across U.S. National Ecological Observation Network (NEON) sites that showed similar capabilities of GEDI with airborne laser scanning (ALS) for tree diversity.

GEDI figure 7
Figure 7. [Top] Protected Areas (PAs) such as national parks can reduce habitat loss and degradation (from logging) and extractive behaviors such as hunting (shown in red circle), but this figure shows there are a wide range of real-world outcomes based on management effectiveness. [Middle] PAs are aimed at safeguarding multiple facets of biodiversity, including species richness (SR), functional richness (FR) and phylogenetic diversity (PD). PAs often focus on vertebrate conservation, owing to their threat levels and value to humans – including for tourism. This study focused on wildlife in southeast Asia, with mammals shown here representing a variation of feeding guilds and sizes. The same approach is repeated for birds. [Bottom] Wildlife communities inside PAs and in the surrounding landscape may exhibit distinct levels and types of diversity.
Figure credit: From a 2023 article in Nature.

Competed Science Team Presentations—Session 3

One unique application of GEDI data is using lidar height to improve radiative transfer models for snow processes. Steven Hancock [University of Edinburgh, Scotland] reported on his group’s work studying snow, forest structure, and heterogeneity in forests, explaining that the majority of land surface models used for climate and weather forecasting use one-dimensional (1D) radiative transfer (RT) models driven by leaf area alone. Heterogeneous forests cast shadows and cause the surface albedo to depend upon sun angle and tree height for moderate leaf area indices (LAI), i.e., LAI values from  1-3 – which are common in snow-affected areas. This complexity cannot be represented in 1D models. An RT model can represent the effect of tree height and horizontal heterogeneity to simulate the observed change in albedo with height, which itself spatially varies.

In contrast to a snowy study area, Ovidiu Csillik [NASA/Jet Propulsion Laboratory] and his team are developing statistical models to link GEDI relative height metrics to tropical forest characteristics traceable to inventory measurements. This dataset of forest structure variables over the Amazon will be used to initialize a demographic ecosystem model to produce projections of future potential tropical forest carbon, as demonstrated by Amazon-wide simulations using initializations from airborne lidar sampling.

Wenge Ni-Meister [Hunter College of the City University of New York] is working on improving aboveground biomass estimates using GEDI waveform measurements. Ni-Meister and her team are testing models in both domestic and international tropical and temperate forests.

Breakout Sessions—Session 2

Two more breakout sessions occurred on day two:  

Sean Healey led a discussion on modes of inference for GEDI data. Inference – formally derived uncertainty for area estimates of biomass, height, or other metrics – can take different forms, each of which includes specific assumptions. In this breakout session, participants considered the strengths and limitations of different inference types (e.g., intensity of computation or the ability to use different models).

Laura Duncanson [UMD—GEDI Co-I] led a discussion about facilitation of open science, in other words, how to make GEDI data more accessible and digestible for data users. While GEDI data area free and publicly available via the LP DAAC and ORNL DAAC, gaining access to said data can be intimidating. Sharing more about existing resources and creating new ones can help remove barriers. The LP DAAC and ORNL DAAC have excellent tutorials on GitHub (a cloud-based software development platform that is primarily Python-based), and Google Earth Engine applications are available for accessing and visualizing GEDI data. Future endeavors may include more webinars, R-based tutorials, workshops, and trainings on specific topics and ways to use GEDI data. More information is available via an online compilation of GEDI-related tutorials.

Perspective: A NUVIEW of Earth’s Land Surface

For the second perspective presentation of day two, meeting attendees heard from Clint Graumann, CEO and co-founder of NUVIEW, a company whose mission is to build a commercial satellite constellation of lidar-imaging satellites that will produce 3D maps of the Earth’s entire land surface. Graumann shared NUVIEW’s intent to produce land surface maps on an annual basis and provide a variety of products and services, including digital surface models (DSMs), digital terrain models (DTMs), and a point cloud generated by laser pulses.

Competed Science Team Presentations—Session 4

Laura Duncanson began the second round of science presentations with her group’s research on global forest carbon hotspots. She discussed her 2023 paper in Nature Communications on the effectiveness of global PAs for climate change mitigation – see Figure 8, which found that the creation of PAs led to more biomass – especially in the Amazon. Within GEDI-domain terrestrial PAs, total aboveground biomass (AGB) storage was found to be 125 Pg, which is around 26% of global estimated AGB. Without the existence of PAs, 19.7 Gt of the 125 Pg would have likely been lost.

GEDI figure 8
Figure 8. PAs effectively preserve additional aboveground carbon (AGC) across continents and biomes, with forest biomes dominating the global signal, particularly in South America. The additional preserved AGC (Gt) in WWF biome classes (total Gt + /− SEM*area). World base map made with Natural Earth. The full set of analyzed GEDI data are represented in this figure (n = 412,100,767).
Figure credit: From a 2023 article in Nature Communications.

Another unique application of GEDI data has to do with water on the Earth’s surface. Kyungtae Lee [UMD], who works with Michelle Hofton [UMD—GEDI Co-I], reported that GEDI appears to capture the monthly annual cycle of lake elevation, showing good correlation with the ground-based observations. Lee explained that even though the GEDI lake elevation estimates show systematic biases relative to the local gauges, GEDI captures lake elevation dynamics well – especially the annual cycle variations. This work has the potential to expand knowledge of hydrological significance of lakes, particularly in data-limited areas of the world. Stephen Good [Oregon State University] presented a survey of his team’s recent work integrating observations from GEDI into hydrology and hydraulics studies of how vegetation can block and intercept moving water. The team found important nonlinear relationships between inferred canopy storage and canopy biomass and were able to estimate canopy water storage capacities and map these globally.

Finally, Patrick Burns [NAU], who works with Scott Goetz, presented results using GEDI canopy structure metrics in mammal species distribution models across southeast Asia (specifically focusing on Borneo and Sumatra). The team’s early results indicate that GEDI canopy structure metrics are important in many mammal distribution models and improve model performance for another smaller subset of species. In other words, when looking at predictors like mean annual precipitation or forest structure (forest structure being a metric that GEDI data provide), the GEDI-derived structure metrics are more intuitive and help us understand distributional changes and fine-scale habitat suitability. In a region like southeast Asia, for example, which has undergone high rates of deforestation in the recent decades, forest structure may be a more relevant predictor in a species distribution model (SDM) than other metrics like climate or vegetation composition. The team will continue to produce models for additional species and expand the extent of the analysis to include mainland Asia.

DAY THREE

Competed Science Team Presentations—Session 5

Day three began with the meeting’s last round of competed ST presentations. John Armston presented the progress of GEDI L2B Plant Area Volume Density (PAVD) product validation using a global Terrestrial Laser Scanning (TLS) database and fusion of the L2B product with Landsat time-series for quantifying change in canopy structure from the Australian wildfires of 2019–2020. Participants then heard from Jim Kellner on using machine-learning algorithms for L4A aboveground biomass density (AGBD). The performance of machine-learning algorithms on a testing data set was comparable to linear regressions used for the first releases of GEDI AGBD data products on average – although there were important geographical differences associated with machine learning. One application under investigation is using machine learning to identify new potential stratifications for GEDI footprint aboveground biomass density.

Lastly, Jingyu Dai [New Mexico State University (NMSU)], who works with Niall Hanan [NMSU], presented on her analysis of the global limits to tree height. Her study shows that hydraulic limitation is the most important constraint on maximum canopy height globally. This result is mediated by plant functional type. In addition, rougher terrain promotes forest height at sub-landscape scales by enriching local niche diversity and probability of larger trees.

Perspective from the Data Side

As described in the summary of Ralph Dubayah’s introductory remarks, the LP DAAC and ORNL DAAC play essential roles in the dissemination of GEDI data and the success of the GEDI program. Representatives from each of these DAACs addressed the ST to summarize recent GEDI-related activities.

Aaron Friesz [United States Geological Survey (USGS)] represented the LP DAAC and gave an update on the current archive size, distribution metrics, and outreach activities. He also discussed plans to support the growth and sustainability of the community through collaboration activities that will leverage the GitHub application; he described some of the resources that are available. Friesz then highlighted the USGS Eyes on Earth podcast and the Institute of Electrical and Electronics Engineers (IEEE) Geoscience and Remote Sensing Society (GRSS)’s Down to Earth podcast, which have featured Ralph Dubayah and Laura Duncanson, and shared plans to update the current GitHub tutorials and how-to guides in the Earthdata Cloud of GEDI V2 and V3.

Rupesh Shrestha [ORNL] represented the ORNL DAAC and shared the status of GEDI L3, L4A, and L4B datasets archived there. He gave an overview of data tools and services for the GEDI datasets, which can be found on the GEDI website and GitHub tutorials website. GEDI L3, L4A, and L4B are available on NASA’s Earthdata Cloud and various enterprise-level services, such as NASA’s WorldView, Harmony, and OpenDAP. GEDI data usage metrics, data tutorials and workshops, and outreach activities, as well as other published community and related datasets were also highlighted. GEDI L3, L4A, and L4B have been downloaded over four million times collectively.

Neha Hunka [UMD] gave the final presentation of the meeting on biomass harmonization activities. She reported that the GEDI estimates of aboveground biomass are capable of directly contributing to the United Nations Framework Convention on Climate Change Global Stocktake. Hunka and her colleagues’ research is aimed at bridging the science–policy gap to enable the use of space-based aboveground biomass estimates for policy reporting and impact – see Figure 9.

GEDI figure 9
Figure 9. Forest biomass estimates in the format of Intergovernmental Panel on Climate Change (IPCC) Tier 1 values from NASA GEDI and ESA Climate Change Initiative (CCI) maps.
Figure credit: Neha Hunka

Conclusion

Overall, the 2023 GEDI STM showcased an exceptional array of scientific research that is highly relevant to addressing pressing global challenges and answering key questions about global forest structure, carbon balance, habitat quality, and biodiversity among other topics. As the GEDI instrument enters its second epoch, we are excited to welcome a new competed GEDI science team cohort and look forward to the release of V3 data products later this year.

Ralph Dubayah concluded the STM with a summary of hibernation period goals and a farewell to this iteration of the competed ST. He extended a heartfelt thank you and farewell to Hank Margolis [NASA Headquarters, emeritus] who has been the NASA Program Scientist for the GEDI mission since 2015. Thank you, Hank. We will miss you.

Talia Schwelling
University of Maryland, College Park
tschwell@umd.edu

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      Summary of the 11th ABoVE Science Team Meeting
      Introduction
      The NASA Arctic–Boreal Vulnerability Experiment (ABoVE) is a large-scale ecological study in the northern regions of North America (Alaska and western Canada) that was developed to understand environmental changes in the region and the implications of those changes for society. Funded primarily by the NASA Terrestrial Ecology Program, this 10-year campaign has included field, airborne, and satellite remote sensing research to address its overarching scientific question of how environmental change in the Arctic and boreal region of western North America will affect vulnerable ecosystems and society.
      ABoVE deployed in three phases: 1) ecosystem dynamics (2015–2018); 2) ecosystem services (2017–2022); and 3) analysis and synthesis (2023–present). Now in the last year of the third phase, the Science Team (ST) consists of 67 active NASA-funded projects with more than 1000 individuals participating. The ABoVE ST has met yearly to discuss the progress of individual teams, plan joint field work, and discuss synthesis activities. ABoVE was featured in a 2019 The Earth Observer article, titled “Summary of the 2019 ABoVE Science Team Meeting” [July–August 2019, Volume 31, Issue 4, pp. 19–22], as well as a 2022 The Earth Observer article, titled “Summary of the Eighth ABoVE Science Team Meeting” [September–October 2022, Volume 34, Issue 5, pp. 28–33].
      Meeting Overview
      The 11th – and final – ABoVE Science Team Meeting (ASTM11) was held May 12–15, 2025, with 96 registered in-person attendees meeting at the University of Alaska, Fairbanks (UAF) and 67 registered virtual attendees – see Photo 1. The meeting included presentations from Phase 3 projects and synthesis reports from thematic working groups (WGs). ABoVE partners, including collaborators [e.g., the Department of Energy’s Next Generation Ecosystem Experiment-Arctic (NGEE-Arctic), Polar Knowledge Canada (POLAR), the Canadian Forest Service (CFS), and the Government of the Northwest Territories (GNWT)] and representatives from upcoming NASA campaigns focusing on the Arctic, shared updates on their activities. Additionally, the meeting featured sessions highlighting cross-project activities, e.g., ABoVE’s participation in regional fire workshops. The meeting also focused on collaborations with the Scotty Creek Research Station in Canada, the many types of science communication activities during ABoVE, and projects conducting collaborative research with community or regional partners.
      Photo 1.The 11th Arctic–Boreal Vulnerability Experiment Science Team (ABoVE) meeting group photo of in-person and virtual participants. Photo credit: Peter Griffith, Leane Kending, and David Stroud The meeting included additional team activities designed to encourage collaboration and understanding between team members. There were opportunities for multiple field trips for in-person attendees, including visits to the Alaska Satellite Facility (ASF) at the Geophysical Institute, the Permafrost Tunnel operated by the Cold Regions Research and Engineering Laboratory (CRREL), the Yankovich Road Fire Interpretive Trail, and the Arctic Research Open House at UAF – see ABove Field Trips section to learn more. The meeting offered early career researchers a chance to receive feedback on their posters and participate in an Early Career lunch event. The meeting even hosted an ABoVE bingo competition, which encouraged attendees to make new scientific and social connections – see Photo 2.
      Photo 2. Scott Goetz [University of Northern Arizona—ABoVE Science Team Lead] poses with ABoVE BINGO winner Wanwan Liang [University of Utah]. Photo credit: Wanwan Liang Meeting Opening
      The first day of the meeting began with a series of opening remarks from the ABoVE leadership team. Peter Griffith [NASA’s Goddard Space Flight Center (GSFC)/Science Systems and Applications, Inc. (SSAI)—Chief Scientist, Carbon Cycle and Ecosystems Office (CCEO)], Scott Goetz [Northern Arizona University (NAU)—ABoVE ST Lead], and Ryan Pavlick [NASA Headquarters (HQ)—ABoVE Program Manager] all noted the significance of this final meeting and discussed the major scientific advances of ABoVE made possible through the dedication of ST members, WG leads, planning committees, and contributors who have made ABoVE a success. Goetz reviewed the meeting goals and objectives:
      receive updates about currently funded projects; receive reports on Thematic WG advances with an emphasis on multiple WG and cross-phase synthesis activities; receive updates on research connections with partners and collaborators; discuss, reflect, and document the history of ABoVE, including major advances, lessons learned, and items to accomplish in the time remaining; and celebrate ABoVE success stories, with advice for potential future NASA large-scale coordinated campaigns. Working Group Presentations and Breakouts
      Throughout the first few days of the meeting, leads for the thematic working groups (WG) presented synthetic overviews of the research efforts of their group members, identified current gaps in planned or completed research, and discussed potential future work. Following these presentations, breakout groups convened to discuss future activities of the WGs. Short summaries of each presentation are available below. Together, these presentations demonstrate the highly interconnected nature of carbon cycles, hydrology, permafrost dynamics, and disturbance regimes in Arctic–boreal ecosystems. The presentations also showcase the substantial ongoing WG efforts to synthesize findings and identify critical knowledge gaps for future research priorities.
      Vegetation Dynamics Working Group
      WG Leads: Matthew Macander [Alaska Biological Research, Inc. (ABR)] and Paul Montesano [GSFC/ADNET Systems Inc.]
      The Vegetation Dynamics WG discussed new advances in understanding Arctic–boreal vegetation structure and function that have been made over the past 10 years through comprehensive biomass maps and multidecadal trend analyses. ABoVE research revealed a critical boreal forest biome shift with greening in nitrogen-rich northern forests and browning in drought-stressed southern forests. The group has identified key knowledge gaps in predicting post-fire vegetation recovery and detecting pervasive declines in vegetation resilience across southern boreal forests. The results suggest higher vulnerability to abrupt forest loss that could dampen the expected increase in carbon sequestration under future climate scenarios.
      Spectral Imaging Working Group
      WG Leads: Fred Huemmrich [GSFC/University of Maryland Baltimore County] and Peter Nelson [Laboratory of Ecological Spectroscopy (LECOSPEC)]
      Over the past year, the Spectral Imaging WG focused on the fundamental scale problem in Arctic ecology, which refers to the mismatch between observation scales and ecological process scales, which span spatial scales from leaf level to larger study areas and temporal scales from minutes to decades. The Airborne Visible/Infrared Imaging Spectrometer – Next Generation (AVIRIS-NG) and AVIRIS-3 datasets provide the first broad-area and high-spatial and spectral resolution coverage of high-latitude terrestrial ecosystems. The WG is now completing a scaling synthesis paper and preparing for the new era of data-rich spectral imaging with improved capabilities in data management, machine learning, and modeling applications for high-latitude research.
      Modeling Working Group
      WG Lead: Josh Fisher [Chapman University]
      The Modeling WG aims to reduce model uncertainties in simulations and projections in the Arctic–boreal region across all ABoVE ecosystem indicators. The WG had polled the ST to determine the variables most needed for their Earth system models and is now using the field, airborne, and satellite datasets to better constrain these models. This WG discussed the benefits to the modeling community of transforming the more than 100 ABoVE datasets into a common grid and projection format used by modelers.
      Carbon Dynamics Working Group
      WG Leads: Jonathan Wang [University of Utah] and Jennifer Watts [Woodwell Climate Research Center (WCRC)]
      The Carbon Dynamics WG has focused its recent work on three areas: decadal syntheses of carbon dioxide (CO2) fluxes from eddy covariance towers, machine learning approaches to upscaling wetland and lake methane (CH4) emissions, and carbon flux modeling across the Arctic–boreal zone. The research integrated atmospheric CO2 observations to improve carbon flux estimates and examined wildfire impacts on both carbon emissions and albedo changes. A significant component of the work involved comparing top-down versus bottom-up carbon flux models, with particular attention to permafrost and peatland regions.
      Hydrology-Permafrost-Wetlands Working Group
      WG Leads: Laura Bourgeau-Chavez [Michigan Technological University], David Butman [University of Washington], John Kimball [University of Montana], and Melissa Schwab [University of California, Irvine]
      The Hydrology–Permafrost–Wetlands WG focused on the processes controlling changes in permafrost distribution and properties and their impacts. There was discussion about the nature, causes, and consequences of hydrologic change (e.g. water storage, mobility, and distribution) and about ecosystem water, energy, and carbon cycle linkages. The presenters mentioned integration of ABoVE datasets with NASA satellite missions [e.g., NASA–Indian Space Research Organisation (ISRO) Synthetic Aperture Radar (NISAR) and Surface Water and Ocean Topography (SWOT) missions]. WG members discussed the connections between ABoVE research and several crosscutting initiatives, including two NASA Arctic coastlines efforts [e.g., Frontlines Of Rapidly Transforming Ecosystems Earth Venture Suborbital (FORTE EVS) campaign and NASA’s Arctic-COastal Land Ocean InteRactionS (COLORS)] and the WCRC’s Permafrost Pathways.
      Disturbance Working Group
      WG Leads: Dong Chen [University of Maryland, College Park] and Jinhyuk Kim [University of California, Irvine]
      The Disturbance WG leads presented their decade-long perspective on disturbance-related research in the ABoVE domain. The presentation incorporated artificial intelligence (AI)-generated summaries of ABoVE-affiliated research across multiple disturbance types, including boreal wildfires, tundra wildfires, and thermokarst/permafrost degradation processes. Chen and Kim acknowledged the extensive contributions from researchers and WG members while outlining future directions for disturbance research.
      Success Stories
      Four “Success Story” presentations and panels took place during ASTM11, which showcased efforts of ABoVE ST members and the leadership team to create and coordinate engagement efforts that spanned individual projects.
      Success Story 1: ABoVE Participation in Regional Fire Workshops
      A substantial portion of ABoVE research has focused on wildfire, and many members of the ST have participated in domestic and international wildfire efforts, connecting researchers with land managers across Alaska and Canada. Randi Jandt [UAF] discussed the Alaska Fire Science Consortium workshops (held in 2017 and 2022). Jenn Baltzer [Wilfred Laurier University (WLU), Canada] discussed Northwest Territories workshops (held in 2014 and 2025), both of which occurred in response to extreme fire seasons in the region. Laura Bourgeau-Chavez outlined ABoVE’s participation in all of these workshops. The workshops facilitated knowledge exchange and collaboration on critical wildfire management priorities, including fire risk assessment, real-time modeling, post-fire effects, and climate change impacts on fire regimes. Key features included small focus groups, field trips to command centers and fire-affected areas, and integration of Indigenous knowledge with new technologies to inform management practices and climate preparedness strategies.
      Success Story 2: Collaborations with Scotty Creek Research Station (SCRS)
      ASTM11 participants watched the film, “Scotty Creek Research Community – The Spirit of Collaboration,” about the SCRS, Canada’s first and only Indigenous-led research station. Following the film, station team members participated in a panel discussion. Ramona Pearson [Ramona Pearson Consulting, Canada], Maude Auclair [WLU], Mason Dominico [WLU], Michael McPhee [Sambaa K’e First Nation, Canada], and William “Bill” Quinton [WLU] discussed their decade-long collaboration with ABoVE. The partnership involved ABoVE collecting airborne hyperspectral, lidar, and radar imagery, while SCRS researchers provided field data for calibration and validation. In 2022, management of the station transitioned to Łı́ı́dlı̨ı̨ Kų́ę́ First Nation (LKFN, Canada), and ABoVE continued collaborating through knowledge exchange, including with early-career researchers and interns. When a 2022 fire destroyed the field station and surrounding area, ABoVE flew additional flights to capture airborne imagery observations to allow comparison of pre- and post-fire conditions.
      Success Story 3: Science Communication
      During the ABoVE field campaign, ST members and CCEO staff engaged in multiple strategies to communicate research results to the public. The activities included interactive engagement through airborne open houses and guest flights, ST member narratives in the “Notes from the Field” blog posts on the NASA Earth Observatory website, and professional multimedia production, including Earth Observatory content and award-winning videos. This multifaceted strategy demonstrates effective scientific communication through direct public engagement and high-quality, multimedia storytelling, making complex research accessible to diverse audiences.
      Success Story 4: Engagement Activities
      This session highlighted several examples of community engagement across the ABoVE domain. Gerald “J.J.” Frost [ABR] discussed synthesizing ecosystem responses and elder observations in western Alaska for his ABoVE project. In another example, ABoVE researchers from Michigan Tech Research Institute (MTRI) partnered with Ducks Unlimited Canada (DUC) and local organizations. Dana Redhuis [MTRI] and Rebecca Edwards [DUC] described their on-the-land camps that provide hands-on training for Northwest Territories youth in wetlands education and ecological monitoring. Kevin Turner [Brock University, Canada] showcased his work with members of the Vuntut Gwitchin First Nation in Old Crow Flats, Yukon, evaluating how climate and land cover change influence water dynamics and carbon balance. These activities demonstrate collaborative research that integrates Indigenous and Western knowledge approaches to address climate change impacts.
      ABoVE Phase 3 Project Presentations
      Project leads of the 20 NASA-funded ABoVE Phase 3 projects presented updates that were organized by scientific theme. The presentations spanned multiple days of the meeting. Table 1 below provides all the project titles, presenter names, and links to each project and presentation. Science results from four of the presentations are shown in Figures 1–4 below as indicated in the table.
      Table 1. An overview ofABoVE Phase 3 projects and presenters. The Project name includes the last name of the Principal Investigator, NASA funding program (TE for Terrestrial Ecology), the year of the NASA solicitation funding the research, and provides a hyperlink to the Project Profile. A hyperlink to each presentation is provided as either PowerPoint (PPT) file or PDF.
      Project   Carbon Presenter(s) Bloom (TE 2021): Using CO2, CH4 and land-surface constraints to resolve sign and magnitude of northern high latitude carbon-climate feedbacks [PDF] Eren Bilir [NASA/Jet Propulsion Laboratory (JPL)]; Principal Investigator (PI): Alexis (Anthony) Bloom [NASA/Jet Propulsion Laboratory (JPL)] Butman (TE 2021): Do changing terrestrial-aquatic interfaces in Arctic-boreal landscapes control the form, processing, and fluxes of carbon? [PPT] David Butman [University of Washington] – see Figure 1 Watts (TE 2021): Contributions of tundra and boreal systems to radiative forcing in North America and Russia under contemporary and future conditions [PPT] Jennifer Watts [Woodwell Climate Research Center] Miller-S (TE 2021): A synthesis and reconciliation of greenhouse gas flux estimates across the ABoVE domain [PDF] Scot Miller [Johns Hopkins University] Michalak (TE 2021): Quantifying climate sensitivities of photosynthesis and respiration in Arctic and boreal ecosystems from top-down observational constraints [PDF] Wu Sun and Jiaming Wen [both Carnegie Institution for Science, CI]; PI: Anna Michalak, [Carnegie Institution for Science] Fire Presenter(s) Bourgeau-Chavez (TE 2021): Integrating remote sensing and modeling to better understand the vulnerability of boreal-taiga ecosystems to wildfire [PPT] Laura Bourgeau-Chavez [Michigan Technological University (MTU)] Walker (TE 2021): Drivers and Impacts of Reburning in boreal forest Ecosystems (DIRE) [PDF] Jeremy Forsythe [Northern Arizona University (NAU)]; PI: Xanthe Walker [NAU] Wang (TE 2021): Quantifying disturbance and global change impacts on multi-decadal trends in aboveground biomass and land cover across Arctic-boreal North America [PPT] Jonathan Wang [University of Utah]– see Figure 2  Wildlife Presenter(s) Boelman (TE 2021): The future of the Forest-Tundra Ecotone: A synthesis that adds interactions among snow, vegetation, and wildlife to the equation [PPT] Natalie Boelman [Lamont-Doherty Earth Observatory, Columbia University] French (TE 2021): Informing wetland policy and management for waterfowl habitat and other ecosystem services using multi-frequency synthetic aperture radar [PPT] Nancy French [MTU] – see Figure 3 Hydrology / Permafrost Presenter(s) Du (TE 2021): High resolution mapping of surface soil freeze thaw status and active layer thickness for improving the understanding of permafrost dynamics and vulnerability [PPT] Jinyang Du [University of Montana] Miller (TE 2021): Enhanced methane emissions in transitional permafrost environments: An ABoVE phase 3 synthesis investigation [PPT] Charles “Chip” Miller [NASA/JPL] Tape (TE 2021): Characterizing a widespread disturbance regime in the ABoVE domain: Beaver engineering [PPT] Kenneth Tape [University of Alaska, Fairbanks] Zhuang (TE 2021): Role of linked hydrological, permafrost, ground ice, and land cover changes in regional carbon balance across boreal and Arctic landscapes [PDF] Qianlai Zhuang [Purdue University]  Vegetation Structure Presenter(s) Duncanson (TE 2021): Mapping boreal forest biomass recovery rates across gradients of vegetation structure and environmental change [PPT] Paul Montesano [GSFC/ADNET Systems Inc]; PI: Laura Duncanson [University of Maryland]—see Figure 4 Lara (TE 2021): ABoVE-Ground characterization of plant species succession in retrogressive thaw slumps using imaging spectroscopy [PPT] Mark Lara [University of Illinois, Urbana-Champaign]  Vegetation Dynamics  Presenter(s) Frost (TE 2021): Towards a warmer, less frozen future Arctic: Synthesis of drivers, ecosystem responses, and elder observations along bioclimatic gradients in western Alaska [PPT] Gerald “J.J.” Frost [ABR] Goetz (TE 2021): Mapping and modeling attributes of an Arctic-boreal biome shift: Phase-3 applications within the ABoVE domain [PPT] Scott Goetz [NAU] Liu (TE 2021): Characterizing Arctic-boreal vegetation resilience under climate change and disturbances [PPT] Yanlan Liu [The Ohio State University] Townsend (TE 2021): Functional diversity as a driver of gross primary productivity variation across the ABoVE domain [PPT] Philip Townsend [University of Wisconsin] Determining Aboveground Biomass Density Using ICESat-2 Data and Modeling
      Figure 1. Despite their relatively small coverage, surface water extent across boreal and arctic lowlands significantly impacts landscape-scale estimates of carbon emissions. The red points on the map in the figure indicates locations of available lake chemistry data derived from ABoVE-supported research, from collaborators, and from a preliminary literature search. Figure credit. David Butman Figure 2. The Arctic-boreal carbon cycle is inextricably linked to vegetation composition and demography, both of which are being altered by climate change, rising levels of atmospheric carbon dioxide, and climate-induced changes in disturbance regimes. The map in the figure shows above-ground biomass (AGB) change across Arctic-boreal North America (2022–1984) created using a machine learning model of AGB trained on from more than 45,000 field plots and 200,000 km2 of airborne lidar data. Figure credit:  Wanwan Liang Figure 3.  Wetlands provide many ecosystem services, including waterfowl habitat, carbon sequestration, and water quality. Northern wetlands Iin the ABovE study area) are threatened from both land use expansion and climate change disruptions, prompting the need for informed management strategies.  Copernicus Sentinel 1 synthetic aperture radar (SAR) data have been used to create this map of flooding (hydroperiod) in wetland areas around the Great Slave Lake in Canada  The color code on the map corresponds to the number of times the SAR imagery indicated a place was flooded (inundated). Such information is helpful for predicting within-season changes in wetland extent. Figure credit: Nancy French Figure 4. Advances have been made in mapping aboveground biomass density (AGBD). Shown here as an example is an AGBD map created using stata from the   ICESat-2 pan-Boreal 30-m (98-ft) tree height and biomass data product [left] and the ensemble mean of the standard deviation of AGBD, aggregated to modelling tiles [right]. Current research aims to expand these maps and understand regional vegetation changes.  Figure credit. Laura Duncanson/data from ORNL DAAC ASTM11 Poster Sessions
      ASTM11 featured 41 research posters across three sessions, organized by thematic area – see Table 3 and Photo 3. The Poster Session agenda details the range of topics that spanned airborne synthetic aperture radar (SAR) and satellite imagery to northern ecosystem fieldwork. Key research topics that emerged included CO2 and CH4 emissions from terrestrial and aquatic systems, ongoing permafrost thaw, fire impacts on carbon cycling, vegetation mapping and biomass estimation, and the impacts of wildlife on the landscape.
      Table 2. A breakdown of ASTM11 poster presentations by science theme.
      Poster Theme Poster Count Carbon Dynamics 5 Crosscutting, Modeling, or Other 6 Fire Disturbance 5 Permafrost, Hydrology, and Wetlands 13 Vegetation Dynamics and Distribution 7 Vegetation Structure and Function 4 Wildlife and Ecosystem Services 1 Photo 3. Poster presentations and sessions during ASTM11 offered opportunities for presenters to share their latest research findings with meeting participants. Photo credit: Elizabeth Hoy ABoVE Field Trips
      ASTM11 offered multiple field trip options across the Fairbanks region of Alaska. The fieldtrips provided ST members an opportunity to interact with the research community – see Photo 4.
      Trip to Alaska Satellite Facility (ASF) and Geophysical Institute
      ASF is a data archive for many SAR datasets from a variety of sensors and has multiple ground station facilities. During the tour, participants visited the ASF operations room and ASF rooftop antenna. The Geophysical Institute tour also featured the Alaska Earthquake Center, Wilson Alaska Technical Center, and Alaska Center for Unmanned Aircraft Systems Integration.
      Trip to Cold Regions Research and Engineering Laboratory (CRREL) Permafrost Tunnel
      The U.S. Army Core of Engineers CRREL Permafrost Tunnel is located in Fox, AK – about 15 km (9 mi) north of Fairbanks. Over 300 m (984 ft) of tunnel have been excavated, exposing Pleistocene ice and carbon-rich yedoma permafrost that ranges in age from 18,000 to 43,000 years old. The tunnel exposes mammoth and bison bones and a variety of permafrost soils. Ongoing projects in the tunnel cover a range of topics, including engineering and geophysical work, Mars analog studies, and biogeochemistry and microbiology of permafrost soils.
      Wildfire Walk: Yankovich Road Fire Interpretive Trail
      On July 11, 2021, a wildfire burned 3.5 acres (14,164 m2) of UAF land. In 2024, the UAF Alaska Fire Science Consortium, Bureau of Land Management Alaska Fire Service, and local artist Klara Maisch collaborated with others to develop the Wildfire Walk at the site. The interpretive trail is an outdoor learning experience with interpretive wayside markers that describe the fire incident, the relationship between wildfire and the boreal forest, fire science and environmental change, and wildfire prevention – see Figure 1.
      UAF Arctic Research Open House
      The UAF Arctic Research Open House was an opportunity for ST members and the public to explore the wide range of research happening at UAF and meet other scientists. ABoVE hosted an information table at the event.
      Photo 4: Collage of images collected during a series of field trips, including [top] the Wildfire Walk along the Alaska Fire Science Consortium, [middle] the Permafrost Tunnel with Tom Douglas [Cold Regions Research and Engineering Laboratory], [bottom left] UAF Arctic Open House ABoVE Table with Margaret “Maggie” Wooton [NASA’s Goddard Space Flight Center (GSFC)/Science System and Applications, Inc. (GSFC/SSAI)], Elizabeth Hoy [GSFC/Global Science & Technology Inc.], and Qiang Zhou [GSFC/SSAI], talking with Logan Berner [Northern Arizona University], [bottom right] the Alaska Satellite Facility ground receiving antenna. Photo credit: Elizabeth Hoy Research Connections
      The success of ABoVE as a large-scale research study over the Arctic and boreal regions within and outside the United States depended on collaboration with multiple organizations. Many of the ABoVE collaborators were able to present at ASTM11.
      Andrew Applejohn [Polar Knowledge Canada (POLAR)] provided details about the scope, mandate, and facilities available through POLAR, a Canadian government agency that has partnered with the ABoVE ST for the duration of the campaign.
      Ryan Connon [Government of the Northwest Territories (GNWT)] discussed the decade-long collaboration between ABoVE and the GNWT, including knowledge sharing of wildlife collar data, field-data ground measurements, and remote sensing analyses.
      Gabrielle Gascon [Canadian Forest Service (CFS), Natural Resources Canada] explained the scope of Canada’s National Forest Inventory and the current CFS focus on wildfire and the CFS’s other areas of research related to the northern regions. Another presentation featured information about various vegetation mapping initiatives where Matthew Macander discussed an Alaska-based effort called AKVEG Map, a vegetation plot database, and Logan Berner [NAU] detailed a pan-Arctic plant aboveground biomass synthesis dataset.
      Brendan Rogers [WCRC] showcased research from Permafrost Pathways, designed to bring together permafrost-related science experts with local communities to inform Arctic policy and develop adaptation and mitigation strategies to address permafrost thaw. NGEE-Arctic is another U.S. government effort that partnered specifically with ABoVE for the duration of the two efforts, and Bob Bolton [Oak Ridge National Laboratory (ORNL)] provided updates on the project.
      Tomoko Tanabe [Japan’s National Institute of Polar Research (JNIPR)] gave a presentation about NIPR to better inform ABoVE scientists about other international Arctic efforts, including a new Japanese Arctic research initiative called the Arctic Challenge for Sustainability III (ArCS III), designed to address social issues related to environmental and social changes in the Arctic.
      Additional Presentations
      An additional presentation aimed to keep the ABoVE ST informed of future NASA Arctic research efforts. Kelsey Bisson [NASA HQ—Program Scientist for the Ocean Biology and Biogeochemistry Program] discussed NASA Arctic-COLORS and Maria Tzortziou [City University of New York/Columbia University, LDEO] discussed the FORTE EVS campaign. The proposed Arctic-COLORS field campaign would quantify the biogeochemical and ecological response of Arctic nearshore systems to rapid changes in terrestrial fluxes and ice conditions. The NASA FORTE EVS campaign will fill a critical gap in understanding Alaska’s northernmost ecosystems by investigating eroding coastlines, rivers, deltas, and estuaries that connect land and sea systems, using airborne platforms.
      Scott Goetz continued with a presentation on U.S. efforts to plan the International Polar Year, scheduled for 2032–2033. Ryan Pavlick provided details on the NISAR mission, which launched after the meeting on July 30, 2025, and discussed other possible future NASA missions.
      A Career Trajectory panel featured Jennifer Watts, Jonathan Wang, Brendan Rogers, and Xiaoran “Seamore” Zhu [Boston University]. The panelists discussed opportunities for researchers from different academic backgrounds and at different career stages, and they provided details about how ABoVE has impacted their careers. They also discussed how NASA campaigns offer opportunities for early career scientists to join a team of peers to grow their abilities throughout the duration of the decade-long research.
      Klara Maisch, a local artist, discussed her work creating science-informed artwork through interdisciplinary collaborations with scientists and other creators – see Figure 5. Maisch described the benefits of partnering with artists to share science with a broad audience and showcased artwork she has created.
      Figure 5. Lower Tanana Homelands – 2022 Yankovich Fire – Plot Painting [left], with original plot reference photograph [right]. Image Credit: Klara Maisch Overarching Presentations
      A series of presentations on the overall structure and outcomes of ABoVE were held during ASTM11. Charles “Chip” Miller [NASA/JPL—Deputy ABoVE ST Lead, ABoVE Airborne Lead] provided details about SAR, hyperspectral, and lidar airborne measurements collected between 2017 and 2024 for the ABoVE Airborne Campaign.
      ABoVE Logistics Office members Daniel Hodkinson [GSFC/SSAI], Sarah Dutton [GSFC/SSAI], and Leanne Kendig [GSFC/Global Science & Technology, Inc. (GST, Inc.)] discussed the many field teams and activities supported during ABoVE. Overall, more than 50 teams were trained in field safety topics, with more than 1,200 training certificates awarded. Elizabeth Hoy [NASA GSFC/GST, Inc.] and Debjani Singh [ORNL] discussed the more than 250 data products developed during the ABoVE program and how to access them through NASA Earthdata. Example visualizations of ABoVE data products can be found in Figure 6.
      Figure 6. ABoVE logo created with different data products from the campaign used to compose each letter.A: Active Layer Thickness from Remote Sensing Permafrost Model, Alaska, 2001-2015;. Tree (inside A): Normalized Difference Vegetation Index (NDVI) Trends across Alaska and Canada from Landsat, 1984-2012;. B: Landsat-derived Annual Dominant Land Cover Across ABoVE Core Domain, 1984-2014;; O: Wildfire Carbon Emissions and Burned Plot Characteristics, NWT, CA, 2014-2016;; V: AVHRR-Derived Forest Fire Burned Area-Hot Spots, Alaska and Canada, 1989-2000;; E: Lake Bathymetry Maps derived from Landsat and Random Forest Modeling, North Slope, AK; and Underline (under O): Plot lines from the ABoVE Planning Tool visualizer. Figure credit: Caitlin LaNeve The Collaborations and Engagement WG held a plenary discussion to highlight the many activities that ABoVE researchers have been involved in over the past decade. The discussion highlighted the need for individual projects and campaign leadership to work together to ensure participation and understanding of planned research at local and regional levels.
      A highlight of the meeting was the “Legacy of ABoVE” panel discussion moderated by Nancy French [MTU]. Panelists included Eric Kasischke [MTU], Scott Goetz, Chip Miller, Peter Griffith, Libby Larson [NASA GSFC/SSAI], and Elizabeth Hoy. Each panelist reflected on their journey to develop ABoVE, which included an initial scoping study developed more than 15 years ago. Members of the panel – all a part of the ABoVE leadership team – joined the campaign at different stages of their career. Each panelist arrived with different backgrounds, bringing their unique perspective to the group that helped to frame the overall campaign development. Following the panel, all ST members who have been a part of ABoVE since its start over a decade ago came to the front for a group photo – see Photo 5.
      Following the panel, the ABoVE ST leads presented their overall thoughts on the meeting and facilitated a discussion with all participants at the meeting. Participants noted the important scientific discoveries made during ABoVE and enjoyed the collegial atmosphere during ASTM11.
      Photo 5. A group photo of participants who have been with ABoVE since its inception: [left to right] Ryan Pavlick, Chip Miller, Elizabeth Hoy, Libby Larson, Peter Griffith, Fred Huemmrich, Nancy French, Scott Goetz, Laura Bourgeau-Chavez, Eric Kasischke, and Larry Hinzman. Photo credit: Peter Griffith Conclusion 
      Overall, ASTM11 brought together an interdisciplinary team for a final team meeting that showcased the many accomplishments made over the past decade. The group outlined current gaps and needs in Arctic and boreal research and discussed possibilities for future NASA terrestrial ecology campaigns. The synthesis science presentations at ASTM11 highlighted the advances ABoVE has made in understanding carbon and ecosystem dynamics in Arctic and boreal regions. It also highlighted the need for further study of cold season and subsurface processes. While this was the last meeting of this ST, research for some projects will continue into 2026, and more publications and data products are expected from ST members in the near term.
      Elizabeth Hoy
      NASA’s Goddard Space Flight Center/Global Science & Technology Inc. (GSFC/GST,Inc.)
      elizabeth.hoy@nasa.gov
      Libby Larson
      NASA’s Goddard Space Flight Center/Science System and Applications, Inc. (GSFC/SSAI)
      libby.larson@nasa.gov
      Annabelle Sokolowski
      NASA GSFC Office of STEM Engagement (OSTEM) Intern
      Caitlin LaNeve
      NASA GSFC Office of STEM Engagement (OSTEM) Intern
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      Science Launching on Northrop Grumman's 23rd Cargo Resupply Mission to the Space Station
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      Deputy Project Manager for Resources – Goddard Space Flight Center
      Katie Bisci, photographed here with a model of NASA’s Nancy Grace Roman Space Telescope, Credit: NASA/Jolearra Tshiteya How are you helping set the stage for the Roman mission?
      I’m a deputy project manager for resources on the Nancy Grace Roman Space Telescope team, sharing the role with Kris Steeley. Together, we oversee the business team, finance, outreach, scheduling, and more. I focus more on the “down and in” of the day-to-day team — helping the financial team, resource utilization across the project, and support service contracts management — while Kris handles more of the “up and out” external work with center management and NASA Headquarters. Kris and I collaborate on many things as well. The two of us have been together on Roman for many years, and we have definitely become one brain in many aspects of the role. The main goal in the job is programmatics: We need to understand and help along the technical parts of the mission, while also supporting cost and schedule control since Roman is a cost-capped mission. I try to make sure that I partner with our engineers to understand the technical part of Roman as much as possible. I find that I can’t do my job well on the programmatic side without working together closely with our engineers to understand the hardware and testing.
      What drew you to NASA? Did you always intend to work here?
      I think I always knew I wanted to go into the business and finance side of things, but I thought I’d end up at a big investment bank. I interned at one during college, but it just didn’t feel right for me. After graduating, I worked on corporate events for defense contractors in New York City. Then my husband got a job in Annapolis, Maryland, and I took a leap and applied for a resource analyst job at NASA, where some college friends were working. Looking back, as an oldest daughter it probably should have been obvious that project management would be a good fit! Once I got to NASA, I was really drawn in by the missions and work we do. It was so different from the corporate world. Being able to work on some of the coolest missions with some of the most brilliant minds out there is a gift. Almost 15 years later, I’m still here.
      How did your career grow from there?
      After serving as a resource analyst in the Safety and Mission Assurance Directorate at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, I moved into the center’s Astrophysics Projects Division, where I began working on Roman in 2012, back when it was just a small study called WFIRST (Wide Field Infrared Survey Telescope). I could never have imagined at the time what that small study would turn into. People at NASA often say they “grew up” on the James Webb Space Telescope, and for me I definitely “grew up” on Roman. I became the mission business manager, then financial manager, and now a deputy project manager for resources. I feel lucky that most of my career has been spent on Roman. Adding it up, I’ve been on this project for over a decade. I’ve worked with so many amazing people, not just at NASA Goddard, but across the United States. It’s hard to believe we are so close to launching.
      What’s been the highlight of your career so far?
      Becoming part of the management team on Roman, for sure. Working with the leadership team has been incredible. The best part about Roman is the people. It still cracks me up to look at the plethora of people we have in the same room for our weekly senior staff meeting, from the programmatic and finance types like myself, to engineers leading super complicated integration and test programs, Ph.D.s, and some of the most brilliant science minds I will probably ever know. The Roman team is amazing, and those relationships are what keep me excited to come to work every day.
      Has your work influenced your understanding or appreciation of astronomy?
      Absolutely. I’ve learned so much just by being around brilliant people like our project scientist Julie McEnery. I even recently gave a talk about Roman at my daughter’s school! Being able to stand up in front of a group of children and talk about what Roman science is going to do is something I never would have been able to do prior to working here. I’ve learned about how the Hubble Space Telescope, Webb, and Roman all build on each other during my time on this project. And it’s really incredible science. I’ve also developed a deep admiration for the engineers who have built Roman. As a business focused person, our engineering team has really helped me understand the different facets of what our engineering team does on Roman. They are so patient with me! It’s really fulfilling to be a small part of something so big.
      What advice do you have for others who are interested in doing similar work?
      If you’re in finance, don’t just learn the numbers — learn the work behind them. Understand the mission, the tech, the people. That’s what helps you move from analyst to leader. People can tell when you really get what they’re doing, and that’s how you become a better partner and manager.
      What’s life like outside NASA?
      I have three kids — ages 9, 5, and 3 — so life is busy! When I’m not working, I’m usually at their sports games or chauffeuring them around to one event or another. It’s a little bit of a rat race, but this season of life is also really fun. Recently, my family and I have gotten back into traveling now that my kids are a little bit older. We took a spring break trip to Europe, which was fantastic.  Spending time with my family and friends is everything. Whether it’s going to the beach, spending time at the pool, or hanging out on the sideline of a lacrosse game, just like at work it’s being with my people that I thrive on. And maybe one day I will have time for more hobbies again!
      By Ashley Balzer
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
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      Last Updated Aug 26, 2025 EditorAshley BalzerLocationGoddard Space Flight Center Related Terms
      Goddard Space Flight Center Nancy Grace Roman Space Telescope People of Goddard View the full article
    • By European Space Agency
      The European Space Agency’s Jupiter Icy Moons Explorer (Juice) is on track for its gravity-assist flyby at Venus on 31 August, following the successful resolution of a spacecraft communication anomaly that temporarily severed contact with Earth.
      The issue, which emerged during a routine ground station pass on 16 July, temporarily disrupted Juice’s ability to transmit information about its health and status (telemetry).
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