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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 163 records · Page 9

SU-E-T-245: MR Guided Focused Ultrasound Increased PARP Related Apoptosis On Prostate Cancer in Vivo

Purpose: Our previous study demonstrated that significant tumor growth delay was observed in the mice treated with pulsed high intensity focused ultrasound (pHIFU). The purpose of this study is to understand the cell killing mechanisms of pHIFU. Methods: Prostate cancer cells (LNCaP), were grown orthotopically in 17 nude mice. Tumor-bearing mice were treated using pHIFU with an acoustic power of 25W, pulse width 100msec and 300 pulses in one sonication under MR guidance. Mutiple sonications were used to cover the whole tumor volume. Temperature (less than 40 degree centigrade in the focal spot) was monitored using MR thermometry. Animals were euthanized at pre-determined time points (n=2) after treatment: 0 hours; 6 hrs; 24 hrs; 48 hrs; 4 days and 7 days. Two tumorbearing mice were used as control. Three tumor-bearing mice were treated with radiation (RT, 2 Gy) using 6 MV photon beams. RT treated mice were euthanized at 0 hr, 6 hrs and 24 hrs. The tumors were processed for immunohistochemical (IHC) staining for PARP (a surrogate of apoptosis). A multispectral imaging analysis system was used to quantify the expression of PARP staining. Cell apoptosis was calculated based on the PARP expression level, which is the intensity of the DAB reaction. Results: Our data showed that PARP related apoptosis peaked at 48 hrs and 7 days in pHIFU treated mice, which is comparable to that for the RT group at 24 hrs. The preliminary results from this study were consistent with our previous study on tumor growth delay using pHIFU. Conclusion: Our results demonstrated that non-thermal pHIFU increased apoptotic tumor cell death through the PARP related pathway. MR guided pHIFU may have a great potential as a safe, noninvasive treatment modality for cancer therapy. This treatment modality might be able to synergize with PARP inhibitors to achieve better result.

60 APPLIED LIFE SCIENCES↗

WE-EF-BRA-01: A Dual-Use Optical Tomography System for Small Animal Radiation Research Platform (SARRP)

Purpose: We develop a novel dual-use configuration for a tri-modality, CBCT/bioluminescence tomography(BLT)/fluorescence tomography(FT), imaging system with the SARRP that can function as a standalone system for longitudinal imaging research and on-board the SARRP to guide irradiation. BLT provides radiation guidance for soft tissue target, while FT offers functional information allowing mechanistic investigations. Methods: The optical assembly includes CCD camera, lens, filter wheel, 3-way mirrors, scanning fiber system and light-tight enclosure. The rotating mirror system directs the optical signal from the animal surface to the camera at multiple projection over 180 degree. The fiber-laser system serves as the external light source for the FT application. Multiple filters are used for multispectral imaging to enhance localization accuracy using BLT. SARRP CBCT provides anatomical information and geometric mesh for BLT/FT reconstruction. To facilitate dual use, the 3-way mirror system is cantilevered in front of the camera. The entire optical assembly is driven by a 1D linear stage to dock onto an independent mouse support bed for standalone application. After completion of on-board optical imaging, the system is retracted from the SARRP to allow irradiation of the mouse. Results: A tissue-simulating phantom and a mouse model with a luminescence light source are used to demonstrate the function of the dual-use optical system. Feasibility data have been obtained based on a manual-docking prototype. The center of mass of light source determined in living mouse with on-board BLT is within 1±0.2mm of that with CBCT. The performance of the motorized system is expected to be the same and will be presented. Conclusion: We anticipate the motorized dual use system provide significant efficiency gain over our manual docking and off-line system. By also supporting off-line longitudinal studies independent of the SARRP, the dual-use system is a highly efficient and cost-effective platform to facilitate optical imaging for pre-clinical radiation research. The work is supported by NIH R01CA158100 and Xstrahl Ltd. Drs. John Wong and Iulian Iordachita receive royalty payment from a licensing agreement between Xstrahl Ltd and Johns Hopkins University. John Wong also has a consultant agreement with Xstrahl Ltd.

60 APPLIED LIFE SCIENCES↗

SU-F-J-225: Histology Study of MR Guided Pulsed Focused Ultrasound On Treatment of Prostate Cancer in Vivo

Purpose: Our previous study demonstrated significant tumor growth delay in the mice treated with pulsed high intensity focused ultrasound (pHIFU). The purpose of this study is to understand the cell killing mechanisms of pHIFU. Methods: Prostate cancer cells (LNCaP), were grown orthotopically in 17 nude mice. Tumor-bearing mice were treated using pHIFU with an acoustic power of 25W, pulse width 100msec and 300 pulses in one sonication under MR guidance. Mutiple sonications were used to cover the whole tumor volume. The temperature (less than 40 degree centigrade in the focal spot) was monitored using MR thermometry. Animals were euthanized at pre-determined time points (n=2) after treatment: 0 hours; 6 hrs; 24 hrs; 48 hrs; 4 days and 7 days. Two tumorbearing mice were used as control. Three tumor-bearing mice were treated with radiation (RT, 2 Gy) using 6 MV photon beams. RT treated mice were euthanized at 0 hr, 6 hrs and 24 hrs. The tumors were processed for immunohistochemical (IHC) staining for PARP (a surrogate of apoptosis). A multispectral imaging analysis system was used to quantify the expression of PARP staining. Cell apoptosis was calculated based on the PARP expression level using the DAB analysis software. Results: Our data showed that PARP related apoptosis peaked at 48 hrs and 7 days in pHIFU treated mice, which is comparable to that for the RT group at 24 hrs. The preliminary results from this study were consistent with our previous study on tumor growth delay using pHIFU. Conclusion: Our results demonstrated that non-thermal pHIFU increased apoptotic tumor cell death through the PARP related pathway. MR guided pHIFU may have a great potential as a safe, noninvasive treatment modality for cancer therapy. This treatment modality may synergize with PARP inhibitors to achieve better therapeutic result.

60 APPLIED LIFE SCIENCES↗

WE-FG-BRA-06: Systematic Study of Target Localization for Bioluminescence Tomography Guided Radiation Therapy for Preclinical Research

Purpose: To overcome the limitation of CT/CBCT in guiding radiation for soft tissue targets, we developed a bioluminescence tomography(BLT) system for preclinical radiation research. We systematically assessed the system performance in target localization and the ability of resolving two sources in simulations, phantom and in vivo environments. Methods: Multispectral images acquired in single projection were used for the BLT reconstruction. Simulation studies were conducted for single spherical source radius from 0.5 to 3 mm at depth of 3 to 12 mm. The same configuration was also applied for the double sources simulation with source separations varying from 3 to 9 mm. Experiments were performed in a standalone BLT/CBCT system. Two sources with 3 and 4.7 mm separations placed inside a tissue-mimicking phantom were chosen as the test cases. Live mice implanted with single source at 6 and 9 mm depth, 2 sources with 3 and 5 mm separation at depth of 5 mm or 3 sources in the abdomen were also used to illustrate the in vivo localization capability of the BLT system. Results: Simulation and phantom results illustrate that our BLT can provide 3D source localization with approximately 1 mm accuracy. The in vivo results are encouraging that 1 and 1.7 mm accuracy can be attained for the single source case at 6 and 9 mm depth, respectively. For the 2 sources study, both sources can be distinguished at 3 and 5 mm separations at approximately 1 mm accuracy using 3D BLT but not 2D bioluminescence image. Conclusion: Our BLT/CBCT system can be potentially applied to localize and resolve targets at a wide range of target sizes, depths and separations. The information provided in this study can be instructive to devise margins for BLT-guided irradiation and suggests that the BLT could guide radiation for multiple targets, such as metastasis. Drs. John W. Wong and Iulian I. Iordachita receive royalty payment from a licensing agreement between Xstrahl Ltd and Johns Hopkins University.

60 APPLIED LIFE SCIENCES↗

hdsullivan/ResSR

This is the official implementation of ResSR [1]. ResSR is a computationally efficient MSI-SR method that achieves high-quality reconstructions by using a closed-form spectral decomposition along with a spatial residual correction. ResSR applies singular value decomposition to identify correlations across spectral bands, uses pixel-wise computation to upsample the MSI, and then applies a residual correction process to correct the high-spatial frequency components of the upsampled bands. While ResSR is formulated as the solution to a spatially-coupled optimization problem, we use pixel-wise regularization and derive an approximate closed-form solution, resulting in a pixel-wise algorithm with a dramatic reduction in computation that achieves state-of-the-art reconstructions. [1] Duba-Sullivan, H., Reid, E. J., Voisin, S., Bouman, C. A., & Buzzard, G. T. (2024). ResSR: A Computationally Efficient Residual Approach to Super-Resolving Multispectral Images. arXiv preprint arXiv:2408.13225.

Duba-Sullivan, Haley [Oak Ridge National Laborator↗

Software for High-Resolution Flood Mapping With Sentinel-1 and Sentinel-2 via Misalignment-Robust Cross-Sensor Learning and Generative Despeckling

SF-26-078 This software provides a high-level workflow for satellite-based flood and surface-water mapping using Sentinel-1 SAR and Sentinel-2 multispectral imagery. It supports preparation of remote-sensing data, training and evaluation of deep-learning models, and generation of high-resolution water extent predictions, including methods to improve robustness to SAR speckle noise and cross-sensor image misalignment.

Feinstein, Jeremy [Argonne National Laboratory (AN↗

Effective Cloud Detection and Segmentation Using a Gradient-Based Algorithm for Satellite Imagery: Application to Improve PERSIANN-CCS

The effective identification of clouds and monitoring of their evolution are important toward more accurate quantitative precipitation estimation and forecast. In this study, a new gradient-based cloud-image segmentation algorithm is developed using image processing techniques. This method integrates morphological image gradient magnitudes to separate cloud systems and patches boundaries. A varying scale kernel is implemented to reduce the sensitivity of image segmentation to noise and to capture objects with various finenesses of the edges in remote sensing images. The proposed method is flexible and extendable from single to multispectral imagery. Case studies were carried out to validate the algorithm by applying the proposed segmentation algorithm to synthetic radiances for channels of the Geostationary Operational Environmental Satellite ( GOES-16) simulated by a high-resolution weather prediction model. The proposed method compares favorably with the existing cloud-patch-based segmentation technique implemented in the Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks–Cloud Classification System (PERSIANN-CCS) rainfall retrieval algorithm. Evaluation of event-based images indicates that the proposed algorithm has potentials comparing to the conventional segmentation technique used in PERSIANN-CCS to improve rain detection and estimation skills with an accuracy rate of up to 98% in identifying cloud regions.

54 ENVIRONMENTAL SCIENCES↗

Integrating LEO and GEO Observations: Toward Optimal Summertime Satellite Precipitation Retrieval

Abstract Reliable quantitative precipitation estimation with a rich spatiotemporal resolution is vital for understanding the Earth’s hydrological cycle. Precipitation estimation over land and coastal regions is necessary for addressing the high degree of spatial heterogeneity of water availability and demand, and for resolving the extremes that modulate and amplify hazards such as flooding and landslides. Advancements in computation power along with unique high spatiotemporal and spectral resolution data streams from passive meteorological sensors aboard geosynchronous Earth-orbiting (GEO) and low Earth-orbiting (LEO) satellites offer exciting opportunities to retrieve information about surface precipitation phenomena using data-driven machine learning techniques. In this study, the capabilities of U-Net–like architecture are investigated to map instantaneous, summertime surface precipitation intensity at the spatial resolution of 2 km. The calibrated brightness temperature products from the Global Precipitation Measurement (GPM) Microwave Imager (GMI) radiometer are combined with multispectral images (visible, near-infrared, and infrared bands) from the Advanced Baseline Imager (ABI) aboard the GOES-R satellites as main inputs to the U-Net–like precipitation algorithm. Total precipitable water and 2-m temperature from the Global Forecast System (GFS) model are also used as auxiliary inputs to the model. The results show that the U-Net–like algorithm can capture fine-scale patterns and intensity of surface precipitation at high spatial resolution over stratiform and convective precipitation regimes. The evaluations reveal the potential of extracting relevant, high spatial features over complex surface types such as mountainous regions and coastlines. The algorithm allows users to interpret the inputs’ importance and can serve as a starting point for further exploration of precipitation systems within the field of hydrometeorology.

Meteorology & Atmospheric Sciences↗

Thunderstorm Cloud-Type Classification from Space-Based Lightning Imagers

The organization and structure of thunderstorms determines the extent and severity of their hazards to the general public and their consequences for the Earth system. Distinguishing vigorous convective regions that produce heavy rain and hail from adjacent regions of stratiform clouds or overhanging anvil clouds that produce light to no rainfall is valuable in operations and physical research. Cloud-type algorithms that partition convection from stratiform regions have been developed for space-based radar, passive microwave, and now Geostationary Operational Environmental Satellites (GOES) Advanced Baseline Imager (ABI) multispectral products. However, there are limitations for each of these products including temporal availability, spatial coverage, and the degree to which they based on cloud microphysics. We report we have developed a cloud-type algorithm for GOES Geostationary Lightning Mapper (GLM) observations that identifies convective/nonconvective regions in thunderstorms based on signatures of interactions with nonconvective charge structures in the lightning flash data. The GLM sensor permits a rapid (20 s) update cycle over the combined GOES-16–GOES-17 domain across all hours of the day. Storm regions that do not produce lightning will not be classified by our algorithm, however. The GLM cloud-type product is intended to provide situational awareness of electrified nonconvective clouds and to complement other cloud-type retrievals by providing a contemporary assessment tied to lightning physics. We propose that a future combined ABI–GLM cloud-type algorithm would be a valuable product that could draw from the strengths of each instrument and approach.

54 ENVIRONMENTAL SCIENCES↗

Extreme heat vulnerability of manufactured housing in arid urban environments

This article explores the role of land cover in relation to housing type and tenure in shaping exposure to extreme urban heat, focusing on residents of mobile and manufactured housing (MH). We hypothesize that MH residents will experience greater exposure to extreme heat than those living in other housing types due to lower levels of proximate vegetation. This hypothesis is based on the unique property relations and tenure regimes that characterize MH, which may disincentivize investments in planting and maintaining trees and vegetation in arid environments. To test this hypothesis, we compare the amount of vegetation on properties across housing types, within-type tenure arrangements and between three urbanized areas in Arizona with different levels of exposure to extreme heat. To conduct this comparison, we combine multispectral land cover data for 1.7 million parcels with tax assessor data and building footprints to measure land cover at a high resolution. We find that MH units have significantly less vegetation than single-family residential properties, and that MH units in MH parks have less vegetation than those on individual lots. We conclude that municipalities should promote (e.g. through incentives or other policy interventions) the planting of more vegetation around MH units where there is a risk of extreme heat exposure. Future research can expand this analysis with a closer examination of how municipal ordinances and policies affect land cover by housing type and tenure.

heat↗

An assessment of multimodal imaging of subsurface text in mummy cartonnage using surrogate papyrus phantoms

Ancient Egyptian mummies were often covered with an outer casing, panels and masks made from cartonnage: a lightweight material made from linen, plaster, and recycled papyrus held together with adhesive. Egyptologists, papyrologists, and historians aim to recover and read extant text on the papyrus contained within cartonnage layers, but some methods, such as dissolving mummy casings, are destructive. The use of an advanced range of different imaging modalities was investigated to test the feasibility of non-destructive approaches applied to multi-layered papyrus found in ancient Egyptian mummy cartonnage. Eight different techniques were compared by imaging four synthetic phantoms designed to provide robust, well-understood, yet relevant sample standards using modern papyrus and replica inks. The techniques include optical (multispectral imaging with reflection and transillumination, and optical coherence tomography), X-ray (X-ray fluorescence imaging, X-ray fluorescence spectroscopy, X-ray micro computed tomography and phase contrast X-ray) and terahertz-based approaches. Optical imaging techniques were able to detect inks on all four phantoms, but were unable to significantly penetrate papyrus. X-ray-based techniques were sensitive to iron-based inks with excellent penetration but were not able to detect carbon-based inks. However, using terahertz imaging, it was possible to detect carbon-based inks with good penetration but with less sensitivity to iron-based inks. The phantoms allowed reliable and repeatable tests to be made at multiple sites on three continents. Finally, the tests demonstrated that each imaging modality needs to be optimised for this particular application: it is, in general, not sufficient to repurpose an existing device without modification. Furthermore, it is likely that no single imaging technique will to be able to robustly detect and enable the reading of text within ancient Egyptian mummy cartonnage. However, by carefully selecting, optimising and combining techniques, text contained within these fragile and rare artefacts may eventually be open to non-destructive imaging, identification, and interpretation.

60 APPLIED LIFE SCIENCES↗

Major to trace element imaging and analysis of iron age glasses using stage scanning in the analytical dual beam microscope (tandem)

Dark and clear silicate glasses formed during an iron age vitrification event ≈ 1500 years ago at the Broborg hillfort near Uppsala, Sweden have been analyzed using a scanning electron microscope equipped with a micro-X-ray fluorescence (μXRF) spectrometer. Correlated µXRF and electron beam-induced energy dispersive spectrometry (EDS) X-ray maps were collected via stage-scanning at constant velocity. This coupled procedure represents a new approach for the cultural heritage community to conduct analytical studies of archaeometric specimens composed of metal, ceramic, or mixed inorganic/organic materials, where major and trace element compositions are registered in space for areas up to the centimeter-length scale at micrometer-scale resolution. Overview images were used to select areas for EDS beam scan maps correlated with multispectral cathodoluminescence (CL) imaging and co-located quantitative EDS and μXRF point analysis. Fe, Ca, Mg, Ti, P, Mn, Zr, Zn, and Y are enriched in the dark glass, while Si, Al, K, Na, Ba, Sr, Rb, and Ga are enriched in the clear glass. Unmelted material is comprised predominately of quartz (SiO 2 ) along with trace apatite (Ca 5 (PO 4 ) 3 [Cl,OH]) and zircon (ZrSiO 4 ). Multivariate statistical analysis was used to measure the area fractions of high variance components while lower variance components represented phase mixtures. Differences between calculated melt viscosities for the glass compositions are consistent with field and laboratory observations. Coupled large area EDS and μXRF imaging shows significant promise for informed selection of higher spatial resolution and higher sensitivity follow-up studies, e.g., those performed using synchrotron analysis.

36 MATERIALS SCIENCE↗

Heterodyne spectrometer sensitivity limit for quantum networking

We report optical heterodyne detection-based spectrometers are attractive due to their relatively simple construction and ultrahigh resolution. Here we demonstrate a proof-of-principle single-mode optical-fiber-based heterodyne spectrometer that has picometer resolution and quantum-limited sensitivity around 1550 nm. Moreover, we report a generalized quantum limit of detecting broadband multispectral-temporal-mode light using heterodyne detection, which provides a sensitivity limit on a heterodyne detection-based optical spectrometer. We then compare this sensitivity limit to several spectrometer types and dim light sources of interest such as spontaneous parametric downconversion, Raman scattering, and spontaneous four-wave mixing. We calculate that the heterodyne spectrometer is significantly less sensitive than a single-photon detector and is unable to detect these dim light sources, except for the brightest and narrowest-bandwidth examples.

47 OTHER INSTRUMENTATION↗

Beam combining of high-power terahertz lasers with semiconductor metasurface gratings

Spectral beam combining (SBC) of an array of single-mode lasers has the potential for realizing a chip-scale electrically tunable multispectral laser source without any moving parts and with emission at closely spaced discrete frequencies. Here, we demonstrate SBC of an array of single-mode THz quantum-cascade lasers (QCLs) with small frequency spacing. Semiconductor-based metasurface THz blazed gratings are developed for integration with QCLs in a compact cryocooler setup. Single-lobed beams of four QCLs emitting around 3.2 THz and spectrally separated by ~14 GHz are combined to achieve collinear propagation of spatially overlapped and collimated beams in the far field with ≲ 0.1° of pointing error. Peak optical power in the range 50–100 mW is detected from each of the QCLs after combining. The dense frequency spacing in our method provides a pathway to incorporate tens of QCLs on a chip to realize a high-power discretely tunable THz laser source for applications in THz spectroscopy.

Jia, Fei [Lehigh Univ., Bethlehem, PA (United Stat↗

Tularosa Basin Play Fairway Analysis: Hydrothermal Alteration Map

This is a hydrothermal alteration map of the Tularosa Basin area, New Mexico and Texas that was created using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) multispectral data band ratios based upon diagnostic features of clay, calcite, silica, gypsum, ferric iron, and ferrous iron. Mesoproterozoic granite in the San Andreas Range often appeared altered, but this may be from clays produced by weathering or, locally, by hydrothermal alteration. However, no field checking was done. This work was done under U.S. D.O.E. Contract #DE-EE0006730

15 GEOTHERMAL ENERGY↗

RiverPIXELS: paired Landsat images and expert-labeled sediment and water pixels for a selection of rivers v1.0

RiverPIXELS contains GeoTIFFs of hand-labeled water and sediment pixels from Landsat images containing rivers. Each of the 104 labeled patches contains 256 x 256 Landsat pixels (30 meter resolution). Our aim in releasing RiverPIXELS is to provide an "off-the-shelf" training and testing dataset for building machine-learned models to automatically identify rivers from multispectral imagery. While a number of trained models and/or surface water products already exist, RiverPIXELS aims for pixel-level accuracy in order to precisely identify river boundaries in particular. Our selection of rivers is heavily Arctic, but we include tropical and temperate rivers as well. Patches are provided for the Colville (7), Indigirka (6), Kolyma (4), Ucayali (54), Waitaki (21), and Yana (12) Rivers. For each patch, all surface water pixels are labeled (1) and all in-channel sediment pixels are labeled (2). Sediments not in-channel are considered part of the land (0) class. RiverPIXELS also includes paired surface water data from the Global Surface Water dataset that may be useful as additional features in machine learning models. Each patch therefore contains four aligned GeoTIFFs: labeled, landsat, gswmo, and gswocc.

54 ENVIRONMENTAL SCIENCES↗

Topography and Functional Traits Control the Distribution of Key Shrub Plant Functional Types in Low-Arctic Tundra: Supporting Data

High-resolution classification maps derived from occupied aerial systems (UASs). The UAS data were collected in August 2021 using a Skydio 2+ drone equipped with a 4K resolution red-green-blue (RGB) camera (2024 Skydio Inc) and a 3DR SOLO Quadcopter carried a Parrot Sequoia+ Multispectral Sensor (2023 Parrot Drone SAS). This package includes vegetation classification maps at four locations around Next Generation Ecosystem Experiment Arctic (NGEE Arctic) Council watershed study site on the Seward Peninsula, Alaska. The classification maps were generated using a combination of RGB and canopy height information. The map data and metadata are provided as ENVI image (.dat) and text (.txt, *hdr) formats. Additional map quicklooks are provided as GIS *.kml files. These datasets are provided in support of Yang et al., (In review), “Topography and Functional Traits Control the Distribution of Key Shrub Plant Functional Types in Low-Arctic Tundra”.The Next-Generation Ecosystem Experiments: Arctic (NGEE Arctic), was a 15-year research effort (2012-2027) to reduce uncertainty in Earth System Models by developing a predictive understanding of carbon-rich Arctic ecosystems and feedbacks to climate. NGEE Arctic was supported by the Department of Energy's Office of Biological and Environmental Research.The NGEE Arctic project had two field research sites: 1) located within the Arctic polygonal tundra coastal region on the Barrow Environmental Observatory (BEO) and the North Slope near Utqiagvik (Barrow), Alaska and 2) multiple areas on the discontinuous permafrost region of the Seward Peninsula north of Nome, Alaska.Through observations, experiments, and synthesis with existing datasets, NGEE Arctic provided an enhanced knowledge base for multi-scale modeling and contributed to improved process representation at global pan-Arctic scales within the Department of Energy's Earth system Model (the Energy Exascale Earth System Model, or E3SM), and specifically within the E3SM Land Model component (ELM).

54 ENVIRONMENTAL SCIENCES↗

Integrating Remote Sensing, Field Observations, and Models to Understand Disturbance and Climate Effects on the Carbon Balance of the West Coast U.S.

As an element of NACP research, the proposed investigation is a two pronged approach that derives and evaluates a regional carbon (C) budget for Oregon, Washington, and California. Objectives are (1) Use multiple data sources, including AmeriFlux data, inventories, and multispectral remote sensing data to investigate trends in carbon storage and exchanges of CO 2 and water with variation in climate and disturbance history; (2) Develop and apply regional modeling that relies on these multiple data sources to reduce uncertainty in spatial estimates of carbon storage and NEP, and relative contributions of terrestrial ecosystems and anthropogenic emissions to atmospheric CO 2 in the region; (3) Model terrestrial carbon processes across the region, using the Biome-BGC terrestrial ecosystem model, and an atmospheric inverse modeling approach to estimate variation in rate and timing of terrestrial uptake and feedbacks to the atmosphere in response to climate and disturbance.

54 ENVIRONMENTAL SCIENCES↗