Adam Erickson

• PhD
• PostDoc Position at National Aeronautics and Space Administration

A number of studies have begun to elucidate the emergent nature of life produced by deep interconnected biological networks, from the evolution of organismal metabolic, proteomic, and regulatory networks to ecological trophic and chemical signaling networks. Systems and synthetic biology, ecology, and bioinspired computing are uncovering the deep a...

The regeneration niche of trees greatly narrows the fundamental niche and is sensitive to climatic change. Development from seed and phenology are regulated by biological and environmental controls, shaping forest successional pathways. We hypothesized that recent climate change is reducing regeneration suitability in northern forests. We used a pr...

Human activities are driving climatic warming and more frequent extreme weather, persistent throughout the recent warming hiatus. The effects of these changes on vegetation phenology remains poorly understood. Forest phenology studies typically focus on the length of the growing season and related changes in carbon uptake. Changes to tree regenerat...

New institutions are critically needed to improve the resilience of social–ecological systems globally. Watershed management offers an important model due to its ability to govern mixed-ownership landscapes through common property regimes, translating national goals into local action. Here, I assess the efficacy of state watershed management instit...

Collaborative watershed management incorporates a number of recent innovations in natural resource management, from ecosystem-based management to adaptive co-management of social-ecological systems. Facing jurisdictional barriers to compliance with landmark federal environmental laws, state governments in the Pacific region embraced collaborative w...

While radiative forcing and thus land surface temperatures have been shown to positively correlate with fire severity, precipitation, and lightning strike frequency, the effects of human activity on fire regimes remain difficult to disentangle from geophysical drivers given co-variation between these factors. Here, I analyze fire regimes in the 191...

The population structure of forests is shaped by balancing the opposing forces of regeneration and mortality, each of which influence C turnover rates and are sensitive to climate. Regeneration underlies the migrational potential of forests to climatic change and remains underserved in modeling studies. Our objective was to test the hypothesis that...

Reliable estimates of canopy light transmission are critical to understanding the structure and function of vegetation communities but are difficult and costly to attain by traditional field inventory methods. Airborne laser scanning (ALS) data uniquely provide multi-angular vertically resolved representation of canopy geometry across large geograp...

Soil moisture is a key limiting factor of plant productivity in boreal and montane regions, producing additional climate feedbacks through evaporation, regeneration, mortality, and respiration. Understory solar irradiation – the primary driver of surface temperature and evaporative demand – remains poorly represented in vegetation models due to a l...

National Academies' Decadal Survey, Thriving on Our Changing Planet, recommended Surface Biology and Geology (SBG) as a "Designated Targeted Observable" (DO). The SBG DO is based on the need for capabilities to acquire global, high spatial resolution, visible to shortwave infrared (VSWIR; 380-2500 nm; ~30 m pixel resolution) hyperspectral (imaging...

Modeling forest ecosystems is a landmark challenge in science, due to the complexity of the processes involved and their importance in predicting future planetary conditions. While there are a number of open‐source forest biogeochemistry models, few papers exist detailing the software development approach used to develop these models. This has left...

Precise registration of forest inventory plots is a prerequisite for optimal integration of field measurements with high-resolution remotely sensed data, including Airborne Laser Scanning (ALS) and very high resolution (VHR) satellite imagery. Plot positional uncertainty propagates through statistical modeling procedures and, ultimately, reduces th...

State-of-the-art forest models are often complex, analytically intractable, and computationally expensive, due to the explicit representation of detailed biogeochemical and ecological processes. Different models often produce distinct results while predictions from the same model vary with parameter values. In this project, we developed a rigorous...

This paper presents the results of the Combined Positioning-Reflectometry Galileo Code Receiver for Forest Management (COREGAL) project. The system architecture is presented, focusing on the Positioning and Reflectometry results using Galileo E1 and E5 signals. The receiver is the main sensor platform for positioning and biomass estimation, the lat...

Erde Gym is a toolkit for developing and comparing optimization algorithms in the geosciences with a focus on reinforcement learning. Erde Gym is built on two core Python frameworks: (1) OpenAI Gym for developing and comparing reinforcement learning algorithms; (2) Erde, a simple universal API and toolkit for geoscientific simulation models. Additi...

Modeling forest ecosystems is a landmark challenge in science, due to the complexity of the processes involved and their importance in predicting future planetary conditions. While there are a number of open-source forest biogeochemistry models, few papers exist detailing the software development approach used to develop these models. This has left...

Recent advances in forest ecosystem modeling allow the simulation of a suite of dynamics relevant to management at the landscape scale. Yet, there is no single scale perfectly suited to the multitude of management-related questions. Here, we conducted a model intercomparison exercise using two forest biogeochemistry models, PPA-BGC and LANDIS-II. W...

Over the past two decades, a new generation of terrestrial biosphere models blended principles from physical 'big-leaf' models and individual-based 'gap' models into new hybrid models. This was done to reduce uncertainties in forests through explicit inclusion of vegetation dynamics. Early models along this line include HYBRID, LPJ-GUESS, and SEIB,...

Over the past 80 years, forest models have progressed from empirical linear models to physiological process models to hybrids of both. Early empirical models simulated the growth and yield of pure even-aged forest stands. Four decades later, individual-based multi-species physiological gap models emerged with JABOWA and FORET. Despite reasonable fi...

A summary of my previous research applications of machine learning to produce the first next-generation forest model, radiative transfer model emulator for a GNSS-R system, and global wood density map for terrestrial biogeochemistry models.

Light detection-and-ranging (LiDAR) and photogrammetric point clouds provide complementary information on forest structure. Sampling biases for airborne and terrestrial data reflect differences in sensor position and orientation. While airborne laser scanning is widely used in forestry for its ability to provide three-dimensional information across...

In western Canada, the effects of warming and increasing human activity may alter the structure, composition, and function of forests, producing quantitatively and qualitatively different understory light conditions. While difficult to measure directly, process-based models may facilitate inference of historical forest states. Yet, existing models...

Research Statement dated May 2, 2017 for my application to the DoD Forest Ecosystem Model Comparison project with the LANDIS-II and SORTIE-PPA modeling groups.

Airborne Laser Scanning (ALS) and terrestrial photogrammetry are methods applicable for mapping forested environments. While ground-based techniques provide valuable information about the forest understory, the measured point clouds are normally expressed in a local coordinate system, whose transformation into a georeferenced system requires additi...

Airborne Laser Scanning (ALS) and terrestrial photogrammetry are methods applicable for mapping forested environments. While ground-based techniques provide valuable information about the forest understory, the measured point clouds are normally expressed in a local coordinate system, whose transformation into a georeferenced system requires additi...

Over the past two decades, contemporary state-level watershed management burgeoned in the Pacific Northwest. This research offers a comparative analysis of contemporary state-level watershed management frameworks in the Pacific Northwest. The four case study areas consist of Idaho, Oregon, Washington, and Northern California. This study begins with...