Sciences and Exploration Directorate

Amanda H Armstrong

(RESEARCH FELLOW)

Amanda H Armstrong's Contact Card & Information.
Email: amanda.h.armstrong@nasa.gov
Org Code: 618
Address:
NASA/GSFC
Mail Code 618
Greenbelt, MD 20771
Employer: UNIV OF MARYLAND COLLEGE PARK

Research Interests


Ecological Modeling

Earth Science: Theory & Modeling

Application and fusion of individual based gap models with remote sensing data products (for both parameterization and initialization/calibration) to improve estimates of vegetation structure, carbon stocks and land cover change at multi-temporal and multi-spatial scales


Environmental Change

Earth Science: Land Cover/Use

Characterizing the vulnerability and response of forested ecosystems to disturbances from land use and climate change


Remote Sensing

Earth Science: Remote Sensing

Development and use of high resolution remote sensing data products toward improvement of metrics and understanding of forest structure and biodiversity

Current Projects


Vulnerability of the Taiga-Tundra Ecotone: Predicting the Magnitude, Variability, and Rate of Change at the Intersection of Arctic and Boreal Ecosystem

Vegetation & Soil

The research project is funded by NASA’s Arctic Boreal Vulnerability Experiment (ABoVE), Phase 2 (80NSSC19M0111; PI: Armstrong). The goal of this work is to examine and quantify the likelihood of predicted changes in Tundra-Taiga Ecotone (TTE) forest structure patterns occurring within the ABoVE extended domain, using airborne imagery and lidar observations, site-scale forest and tundra vegetation modeling, and a Landsat-derived map of the extent & pattern of the TTE.


Ecosystem Functional Diversity of the Circumpolar Arctic Tundra

Ecosystem function

The main objectives of this project are: i) To develop and implement a processing stream for the production of Ecosystem Functional Types and Ecosystem Functional Diversity variables for the circumpolar arctic tundra, ii) To evaluate the environmental and anthropogenic controls on the spatial patterns of Ecosystem Functional Types and Diversity for the arctic tundra with respect to climatic, topographic/geological, and land use gradients, iii) To analyze the relationships between vegetation composition and Ecosystem Functional Types and Diversity for the arctic tundra biome, iv) To assess the inter-annual dynamics of Ecosystem Functional Types and Diversity throughout the arctic tundra over the past 16+ years, v) To assess the conservation priority (e.g. vulnerability) of areas within the arctic tundra biome, based on properties of Ecosystem Functional Diversity (e.g. functional richness, rareness) and their dynamics over time.

Publications


Refereed

2024. "Ecosystem functional types of the circumpolar Arctic tundra based on the seasonal dynamics of vegetation productivity." Environmental Research: Ecology 3 (2): 025003 [10.1088/2752-664x/ad4beb] [Journal Article/Letter]

2024. "Permafrost Carbon: Progress on Understanding Stocks and Fluxes Across Northern Terrestrial Ecosystems." Journal of Geophysical Research: Biogeosciences 129 (3): [10.1029/2023jg007638] [Journal Article/Letter]

2024. "Drivers of heterogeneity in tundra vegetation productivity on the Yamal Peninsula, Siberia, Russia." Environmental Research: Ecology 3 (1): 015003 [10.1088/2752-664x/ad220f] [Journal Article/Letter]

2023. "Influences of Satellite Sensor and Scale on Derivation of Ecosystem Functional Types and Diversity." Remote Sensing 15 (23): 5593 [10.3390/rs15235593] [Journal Article/Letter]

2023. "Patterns of regional site index across a North American boreal forest gradient." Environmental Research Letters [10.1088/1748-9326/acdcab] [Journal Article/Letter]

2022. "Disturbances in North American boreal forest and Arctic tundra: impacts, interactions, and responses." Environmental Research Letters 17 (11): 113001 [10.1088/1748-9326/ac98d7] [Journal Article/Letter]

2020. "A multi-scaled analysis of forest structure using individual-based modeling in a costa rican rainforest." Ecological Modelling 433 109226 [10.1016/j.ecolmodel.2020.109226] [Journal Article/Letter]

2019. "Importance of tree- and species-level interactions with wildfire, climate, and soils in interior Alaska: Implications for forest change under a warming climate." Ecological Modelling 409 108765 [10.1016/j.ecolmodel.2019.108765] [Journal Article/Letter]

2019. "Beyond MRV: high-resolution forest carbon modeling for climate mitigation planning over Maryland, USA." Environmental Research Letters 14 (4): 045013 [10.1088/1748-9326/ab0bbe] [Journal Article/Letter]

2019. "An overview of soils and their relationship to protected areas." The Terrestrial Protected Areas of Madagascar [Article in Book]

2018. "Simulating Forest Dynamics of Lowland Rainforests in Eastern Madagascar." Forests 9 (4): 214 [10.3390/f9040214] [Journal Article/Letter]

2018. "Tropical Rainforest Ecosystems." International Encyclopedia of Geography 1-16 [10.1002/9781118786352.wbieg0644.pub2] [Article in Book]

2018. "Gap models and their individual-based relatives in the assessment of the consequences of global change." Environmental Research Letters 13 (3): 033001 [10.1088/1748-9326/aaaacc] [Journal Article/Letter]

2014. "Simulating the impacts of reduced rainfall on carbon stocks and net ecosystem exchange in a tropical forest." Environmental Modelling & Software 52 200-206 [10.1016/j.envsoft.2013.10.026] [Journal Article/Letter]

2011. "Characterization of Community Composition and Forest Structure in a Madagascar Lowland Rainforest ." Tropical Conservation Science 4 (4): 428-444 [Full Text] [Journal Article/Letter]

2010. "Remote Characterization of Biomass Measurements: Case Study of Mangrove Forests." [Proceedings]

Non-Refereed

2021. "Understanding Active Layer Thickness Variability Under Changing Climatic Conditions Across the North American Taiga-Tundra Ecotone." AGU 2021 Fall Meeting [10.1002/essoar.10509696.1] [Proceedings]

2021. "High Resolution Simulations of Forest Structure Project Heterogeneous Change Across the North American Taiga-Tundra Ecotone." AGU Fall Meeting 2021 [Proceedings]

Positions/Employment


Research Scientist

Universities Space Research Association - GESTAR - Goddard Space Flight Center; Biospheric Sciences Laboratory; Greenbelt, Maryland

May 2019 - Present

·      Principle Investigator of ABoVE Phase 2 project entitled: Vulnerability of the Taiga-Tundra Ecotone: Predicting the Magnitude, Variability, and Rate of Change at the Intersection of Arctic and Boreal Ecosystem

·      Oversight and participation in the development of a tundra-taiga ecotone spatially explicit individual-based gap model, including permafrost, litterfall, allometric and Arctic vegetation sub-routines.

·      Coordination of model initialization with airborne and space-borne tree-cover and tree-cover abruptness datasets.

·      Production of study site forecasting change maps with CMIP6 climate scenarios

·      Communication of research and co-mentoring of PhD student hired for research project


Research Associate

University of Virginia - Department of Environmental Sciences, Charlottesville, VA

April 2018 - Present

·      Development and implementation of a processing stream for the production of Ecosystem Functional Types and Ecosystem Functional Diversity variables for the Circumpolar Arctic Tundra in Google Earth Engine

·      Evaluation of the environmental controls and interannual dynamics of the spatial patterns of EFTs and Diversity for the arctic tundra biome with respect to topographical/geographical and climatic gradients

Communication of EFT processing stream and results of pattern analyses to the scientific community


Research Associate

University of Virginia - Department of Environmental Sciences, Charlottesville, VA

October 2016 - April 2018

·      Development and Application of the UVAFME Forest Model for Alaskan and Canadian Boreal Forest for fusion with remote sensing imagery (Landsat, GLiHT) and climate change scenarios

·      Co-development of permafrost and litterfall subroutines for the UVAFME Model

·      Parameterization of UVAFME for Canadian Parklands drought simulation


Visiting Research Scientist

Universities Space Research Association - GESTAR - NASA Goddard Space Flight Center

January 2015 - April 2019

·      Co-Investigator on Remote Sensing Theory Research entitled: Forest Structural Parameter Retrieval from Coupled Models and Remote Sensing Data Fusion; Research objectives use individual based gap model output to simulate lidar waveform and radar backscatter returns to improve and extend look up tables for current and future lidar/radar missions

·      Investigator on a EO-1 funded project which was undertaken to assess a number of hyperspectral dataset-derived vegetation indices as inputs into individual-based models. Hyperspectral indices include: PAR, faPAR, water stress, plant functional type and chlorophyll.

·      Supporting Cal/Val scientist investigating the effect of satellite orbit degradation and overpass time on spectral stability of EO-1 Hyperion imagery at the Libya-4 and Dome-C PICS sites.

·      Responsible for building a database of forest inventory data collected from Corcovado, Costa Rica and Andros Island, Bahamas EcoSAR calibration sites. Calculated forest attribute and structure variables. Submitted report in June 2015.


Postdoctoral Research Associate, NASA NPP-ORAU

Oak Ridge Associated Universities - Goddard Space Flight Center; Biospheric Sciences Laboratory; Greenbelt, Maryland

July 2012 - November 2014

 • Postdoctoral Research Project entitled Politics and Rice: Deforestation Drivers in Madagascar

• Research combines spatial/temporal remote sensing imagery analysis, ecological modeling, economic research, and forest inventory datasets to correlate fluctuations in the price of rice (the staple commodity) with the rate of deforestation of Madagascar’s remaining primary rainforest. Imagery analysis quantified deforestation rates (and therefore biomass loss) inform the FORMIX3 growth model, parameterized for Madagascar rainforest to project rates of future loss given by a range of price scenarios.

• Responsible for all aspects of research, presentations, travel and manuscript preparations


Postdoctoral Research Associate

University of Maryland - Department of Geography College Park, Maryland

January 2011 - January 2012

 • Responsible for ED modeling effort component of year 1 of NASA’s Carbon Monitoring Systems Project under the direction of PI George Hurtt.

• Developed technological capacity to run high resolution version of the Ecosystem Demography Model to characterize carbon and biomass flux over large domains at unprecedented 1 hectare resolution

• Executed a framework of model experiments designed to isolate the effect of each multi-resolution input datasets and identify the value of each added data layer

• Analyzed forest parameters at multiple scales over multiple input domains in the NE region of the US.

• Presented preliminary results and ongoing research at CMS meetings in March, April, May and Science Definition Team Meeting, June 2011.

• Collaborator on “CMS1 Final Report”

Professional Service


Subject Editor, Ecological Modelling, Elsevier. January 2021 to present