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AmeriFlux Measurement Network: Science Team Research

Description: Research involves analysis and field direction of AmeriFlux operations, and the PI provides scientific leadership of the AmeriFlux network. Activities include the coordination and quality assurance of measurements across AmeriFlux network sites, synthesis of results across the network, organizing and supporting the annual Science Team Meeting, and communicating AmeriFlux results to the scientific community and other users. Objectives of measurement research include (i) coordination of flux and biometric measurement protocols (ii) timely data delivery to the Carbon Dioxide Information and Analysis Center (CDIAC); and (iii) assurance of data quality of flux and ecosystem measurements contributed by AmeriFlux sites. Objectives of integration and synthesis activities include (i) integration of site data into network-wide synthesis products; and (ii) participation in the analysis, modeling and interpretation of network data products. Communications objectives include (i) organizing an annual meeting of AmeriFlux investigators for reporting annual flux measurements and exchanging scientific information on ecosystem carbon budgets; (ii) developing focused topics for analysis and publication; and (iii) developing data reporting protocols in support of AmeriFlux network goals.
Date: December 12, 2012
Creator: Law, B E
Partner: UNT Libraries Government Documents Department

The First State of the Carbon Cycle Report: North American Carbon Budget and Implications for the Global Carbon Cycle: Summary and Frequently Asked Questions

Description: 2-sided color pamphlet on the global carbon cycle and North American carbon budget. Answers these questions: Why should we care about the global carbon cycle; What are the activities that produce emissions from fossil fuels in North America; What are the activities in North America that remove carbon dioxide from the atmosphere; What are the management options for reducing atmospheric carbon dioxide concentrations?
Date: unknown
Creator: Climate Change Science Program (U.S.)
Partner: UNT Libraries Government Documents Department

Carbon Capture and Sequestration

Description: This report covers carbon capture and sequestration (CCS), but not other types of carbon sequestration activities whereby CO2 is removed from the atmosphere and stored in vegetation, soils, or oceans. Forests and agricultural lands store carbon, and the world's oceans exchange huge amounts of CO2 from the atmosphere through natural processes.
Date: February 23, 2009
Creator: Folger, Peter
Partner: UNT Libraries Government Documents Department

Cycling of DOC and DON by Novel Heterotrophic and Photoheterotrophic Bacteria in the Ocean: Final Report

Description: The flux of dissolved organic matter (DOM) through aquatic bacterial communities is a major process in carbon cycling in the oceans and other aquatic systems. Our work addressed the general hypothesis that the phylogenetic make-up of bacterial communities and the abundances of key types of bacteria are important factors influencing the processing of DOM in aquatic ecosystems. Since most bacteria are not easily cultivated, the phylogenetic diversity of these microbes has to be assessed using culture-independent approaches. Even if the relevant bacteria were cultivated, their activity in the lab would likely differ from that under environmental conditions. This project found variation in DOM uptake by the major bacterial groups found in coastal waters. In brief, the data suggest substantial differences among groups in the use of high and molecular weight DOM components. It also made key discoveries about the role of light in affecting this uptake especially by cyanobacteria. In the North Atlantic Ocean, for example, over half of the light-stimulated uptake was by the coccoid cyanobacterium, Prochlorococcus, with the remaining uptake due to Synechococcus and other photoheterotrophic bacteria. The project also examined in detail the degradation of one organic matter component, chitin, which is often said to be the second most abundant compound in the biosphere. The findings of this project contribute to our understanding of DOM fluxes and microbial dynamics supported by those fluxes. It is possible that these findings will lead to improvements in models of the carbon cycle that have compartments for dissolved organic carbon (DOC), the largest pool of organic carbon in the oceans.
Date: December 9, 2008
Creator: Kirchman, David L
Partner: UNT Libraries Government Documents Department

Technical Report: Investigation of Carbon Cycle Processes within a Managed Landscape: An Ecosystem Manipulation and Isotope Tracer Approach

Description: The goal of this research is to provide a better scientific understanding of carbon cycle processes within an agricultural landscape characteristic of the Upper Midwest. This project recognizes the need to study processes at multiple spatial and temporal scales to reduce uncertainty in ecosystem and landscape-scale carbon budgets to provide a sound basis for shaping future policy related to carbon management. Specifically, this project has attempted to answer the following questions: 1. Would the use of cover crops result in a shift from carbon neutral to significant carbon gain in corn-soybean rotation ecosystems of the Upper Midwest? 2. Can stable carbon isotope analyses be used to partition ecosystem respiration into its autotrophic and heterotrophic components? 3. Can this partitioning be used to better understand the fate of crop residues to project changes in the soil carbon reservoir? 4. Are agricultural ecosystems of the Upper Midwest carbon neutral, sinks, or sources? Can the proposed measurement and modeling framework help address landscape-scale carbon budget uncertainties and help guide future carbon management policy?
Date: June 1, 2009
Creator: Griffis, Timothy J; Baker, John M & Billmark, Kaycie
Partner: UNT Libraries Government Documents Department

Science and Technology Development to Integrate Energy Production and Greenhouse Gas Management

Description: This paper reviews the carbon cycle from the point of view of past and present human influence. Potential future human input to the cycle through science and technology to manage atmospheric greenhouse gas are considered. The review suggests that humans will need to ingeniously exploit even more energy to integrate its use with control of atmospheric greenhouse gases. Continuing development and application of energy is essential if the development of human society is to be sustained through the coming centuries. The continuing development of nuclear energy seems an essential energy supply component.
Date: October 3, 2004
Creator: Pendergast, D.
Partner: UNT Libraries Government Documents Department

Ewing Symposium in Honor of Taro Takahashi: The controversial aspects of the contemporary [carbon] cycle

Description: This Ewing Symposium in honor of Taro Takahashi's work on the carbon cycle was held at Lamont-Doherty Earth Observatory, Palisades, New York, on October 26-27, 2000. A program and set of abstracts are appended to this report. A summary of the meeting (included in this report) will be published in Global Biogeochemical Cycles. The theme of the symposium was the magnitude and cause of excess carbon storage on the north temperate continents. Disagreement exists on the relative roles of forest regrowth and fertilization by excess fixed nitrogen and carbon dioxide, as well as the distribution of this storage. Phenomena playing important roles include pre-anthropogenic gradients in carbon dioxide, the so-called rectification effect, uptake and release of carbon dioxide by the ocean, soil nitrogen dynamics, atmospheric carbon-13 gradients, and the role of fire.
Date: December 31, 2001
Creator: Broecker, Wallace Smith
Partner: UNT Libraries Government Documents Department

Is Biopower Carbon Neutral?

Description: This report discusses biomass energy, or bioenergy, which may receive more attention from stakeholders as an alternative to fossil fuels because of its potential to minimize the environmental impacts of energy production, provide energy security, and promote economic development. The report discusses some factors taken into account when considering whether biopower is carbon neutral.
Date: February 4, 2016
Creator: Bracmort, Kelsi
Partner: UNT Libraries Government Documents Department

The Path of Carbon in Photosynthesis VI.

Description: This paper is a compilation of the essential results of our experimental work in the determination of the path of carbon in photosynthesis. There are discussions of the dark fixation of photosynthesis and methods of separation and identification including paper chromatography and radioautography. The definition of the path of carbon in photosynthesis by the distribution of radioactivity Within the compounds is described.
Date: June 30, 1949
Creator: Calvin, M.
Partner: UNT Libraries Government Documents Department

The Terrestrial Biosphere and Global Change: Implications for Natural and Managed Ecosystems

Description: From the perspective of terrestrial ecosystems, the most important component of global change over the next three or four decades will likely be land-use/cover change. It is driven largely by the need to feed the expanding human population, expected to increase by almost one billion (109) people per decade for the next three decades at least. Much of this increase will occur in developing countries in the low-latitude regions of the world. To meet the associated food demand, crop yields will need to increase, consistently, by over 2% every year through this period. Despite advances in technology, increasing food production must lead to intensification of agriculture in areas which are already cropped, and conversion of forests and grasslands into cropping systems. Much of the latter will occur in semi-arid regions and on lands which are marginally suitable for cultivation, increasing the risk of soil erosion, accelerated water use, and further land degradation.
Date: 1997
Creator: Walker, Brian & Steffen, WIll
Partner: UNT Libraries

Ocean Biogeochemistry and Global Change

Description: From the perspective of terrestrial ecosystems, the most important component of global change over the next three or four decades will likely be land-use/cover change. It is driven largely by the need to feed the expanding human population, expected to increase by almost one billion (109) people per decade for the next three decades at least. Much of this increase will occur in developing countries in the low-latitude regions of the world. To meet the associated food demand, crop yields will need to increase, consistently, by over 2% every year through this period. Despite advances in technology, increasing food production must lead to intensification of agriculture in areas which are already cropped, and conversion of forests and grasslands into cropping systems. Much of the latter will occur in semi-arid regions and on lands which are marginally suitable for cultivation, increasing the risk of soil erosion, accelerated water use, and further land degradation.
Date: 1997
Creator: Joint Global Ocean Flux Study
Partner: UNT Libraries

Report on the TCO/GCP Terrestrial Carbon Observations and Model-Data Fusion Workshop

Description: The global carbon cycle is of intense interest to policy-makers, the scientific community, and public organizations. As a result, numerous new programmes and projects have been developed over the last few years. TCO and GCP are two such complementary initiatives which share a common goal of advancing the availability of more accurate and mutually consistent estimates of terrestrial carbon sources, sinks and processes, regionally and globally, through syntheses of observations and models. The workshop was intended to advance the availability of more accurate and mutually consistent estimates of the distribution of carbon sources and sinks at a regional and global level. This goal can be achieved by convergence of in situ and satellite observations, experiments and modelling strategies; improvements in data acquisition and sharing; and product generation, distribution and use. The workshop focused on the following questions and associated issues: 1. What carbon cycle data products could be routinely produced from a carbon observation system based on model-data and model-data fusion? 2. What are the main conceptual approaches to assimilating atmospheric carbon content, terrestrial carbon flux and remotely sensed data into coupled atmospheric circulation-carbon cycle models? 3. What is the present and eventual uncertainty regarding the main carbon fluxes at global and regional scale, and how will it be reduced by projects currently underway and about to begin? 4. In what regions, and on what topics, will new data inputs make the largest contribution to reducing the residual uncertainties? What actions should be taken to overcome the gaps and limitations identified?
Date: June 2003
Creator: Quegan, Shaun
Partner: UNT Libraries

Advanced integrated modeling and measurement: The global carbon cycle

Description: Most of the carbon dioxide added to the atmosphere by human activities comes from burning fossil fuels Only about half the CO2 we release into the atmosphere remains there, however, and the fate of the CO2 that does not remain in the atmosphere is uncertain As carbon dioxidecomes in contact with the sea surface it may be absorbed into the ocean, and as it comes in contact with the leaves of plants it may be absorbed and transformed into plant tissue, but the rates at which the sea or land plants can absorb CO2 are poorly characterized Hence, there is a great deal of uncertainty as to how much of the CO2 we release today will be found in the ocean, or in land plants, or in the atmosphere 10, 20 or 100 years from now The nanowing of these uncertainties is essential to making reliable predictions of the climate consequences of fossil fuel burning and deforestation
Date: June 1, 1998
Creator: Duffy, P. B.
Partner: UNT Libraries Government Documents Department

Is Biopower Carbon Neutral?

Description: This report discusses Biomass energy, or bioenergy, which may receive more attention from stakeholders as an alternative to fossil fuels because of its potential to minimize the environmental impacts of energy production, provide energy security, and promote economic development.
Date: September 28, 2015
Creator: Bracmort, Kelsi
Partner: UNT Libraries Government Documents Department

Community Acceptance of Carbon Capture and Sequestration Infrastructure: Siting Challenges

Description: This report discusses the possible role public and community acceptance may play in the siting of CO2 infrastructure for carbon capture and sequestration (CCS). The report reviews what is known about public opinion of CCS as an overall strategy to combat climate change. The report examines community acceptance of CO2 emissions controls, pipelines, and sequestration sites based on analogies, CO2 experience, and focused research. It also discusses community acceptance issues related to selected alternatives to CCS policies, such as investment in renewable energy infrastructure and nuclear power. The report introduces key CCS policy considerations as Congress continues to evaluate opportunities and requirements for carbon control.
Date: July 29, 2008
Creator: Parfomak, Paul W.
Partner: UNT Libraries Government Documents Department

Future Climate Change Research and Observations: GCOS, WCRP and IGBP Learning from the IPCC Fourth Assessment Report

Description: Learning from the authors of the IPCC Fourth Assessment Report and its findings to help guide future strategies for climate change observations and research was the key objective of a workshop organised jointly by the Global Climate Observing System (GCOS), the World Climate Research Programme (WCRP), and the International Geosphere-Biosphere Programme (IGBP) in Sydney, Australia, 4-6 October 2007.
Date: 2008
Creator: International Geosphere-Biosphere Programme
Partner: UNT Libraries

American Leadership for the Global Climate Crisis

Description: This paper discusses several key areas where U.S. policy should be reshaped, both domestically and internationally, to ensure we lead the world towards a safe, sustainable future. We should: Establish a price for carbon by adopting an ambitious 2020 emissions reduction target. Make investments and adopt policies to stimulate a green economy. Lead the world toward an effective and equitable global climate agreement Support efforts to stop emissions from deforestation and degradation in developing countries. Contribute to global financing mechanisms for climate mitigation and adaptation in the developing world. Ensure that climate change-related impacts are addressed under the Endangered Species Act. Improve science and information to prepare communities and ecosystems for unavoidable climate change. Build public support for sustained action to fight climate change
Date: January 2009
Creator: WWF (Organization)
Partner: UNT Libraries

Synthesis of Remote Sensing and Field Observations to Model and Understand Disturbance and Climate Effects on the Carbon Balance of Oregon & Northern California

Description: The goal is to quantify and explain the carbon (C) budget for Oregon and N. California. The research compares "bottom -up" and "top-down" methods, and develops prototype analytical systems for regional analysis of the carbon balance that are potentially applicable to other continental regions, and that can be used to explore climate, disturbance and land-use effects on the carbon cycle. Objectives are: 1) Improve, test and apply a bottom up approach that synthesizes a spatially nested hierarchy of observations (multispectral remote sensing, inventories, flux and extensive sites), and the Biome-BGC model to quantify the C balance across the region; 2) Improve, test and apply a top down approach for regional and global C flux modeling that uses a model-data fusion scheme (MODIS products, AmeriFlux, atmospheric CO2 concentration network), and a boundary layer model to estimate net ecosystem production (NEP) across the region and partition it among GPP, R(a) and R(h). 3) Provide critical understanding of the controls on regional C balance (how NEP and carbon stocks are influenced by disturbance from fire and management, land use, and interannual climate variation). The key science questions are, "What are the magnitudes and distributions of C sources and sinks on seasonal to decadal time scales, and what processes are controlling their dynamics? What are regional spatial and temporal variations of C sources and sinks? What are the errors and uncertainties in the data products and results (i.e., in situ observations, remote sensing, models)?
Date: May 22, 2008
Creator: Law, Beverly; Turner, David; Cohen, Warren & Goeckede, Mathias
Partner: UNT Libraries Government Documents Department

FINAL REPORT: A Study of the Abundance and 13C/12C Ratio of Atmospheric Carbon Dioxide to Advance the Scientific Understanding of Terrestrial Processes Regulating the GCC

Description: The main objective of this project was to continue research to develop carbon cycle relationships related to the land biosphere based on remote measurements of atmospheric CO2 concentration and its isotopic composition. The project continued time-series observations of atmospheric carbon dioxide and isotopic composition begun by Charles D. Keeling at remote sites, including Mauna Loa, the South Pole, and eight other sites. The program also included the development of methods for measuring radiocarbon content in the collected CO2 samples and carrying out radiocarbon measurements in collaboration with Tom Guilderson of Lawrence Berkeley National Laboratory (LLNL). The radiocarbon measurements can provide complementary information on carbon exchange rates with the land and oceans and emissions from fossil-fuel burning. Using models of varying complexity, the concentration and isotopic measurements were used to establish estimates of the spatial and temporal variations in the net CO2 exchange with the atmosphere, the storage of carbon in the land and oceans, and variable isotopic discrimination of land plants.
Date: December 23, 2008
Creator: Keeling, R. F. & Piper, S. C.
Partner: UNT Libraries Government Documents Department

REGULATION OF CARBON SEQUESTRATION AND WATER USE IN A OZARK FOREST: PROPOSING A NEW STRATEGICALLY LOCATED AMERIFLUX TOWER SITE IN MISSOURI

Description: by June 14, 2004, the MOFLUX site was fully instrumented and data streams started to flow. A primary accomplished deliverable for the project period was the data streams of CO{sub 2} and water vapor fluxes and numerous meteorological variables (from which prepared datasets have been submitted to the AmeriFlux data archive for 2004-2006, Additionally, measurements of leaf biochemistry and physiology, biomass inventory, tree allometry, successional trends other variables were obtained.
Date: April 19, 2013
Creator: Pallardy, Stephen G
Partner: UNT Libraries Government Documents Department

Coordination studies with PNNL's global change assessment model: integrated science modeling and applications to the human dimensions. Final technical report for period October 1996 - March 2000

Description: This report outlines the progress on the development and application of Integrated Science Assessment Model (ISAM) supported by the DOE Program on Health and Environmental Research: Environmental Sciences Program under Grant No. DOE DFGO2-96ER62284. As part of this research proposal, we designed the model that better represent spatial variations and treat the process relevant towards evaluating the biogeochemical cycles important to determining atmospheric composition and resulting climatic effects at the regional scale. The process level understanding of regional impacts into the Integrated Assessment (IA) model will help to improve the understanding of climate change impacts and extend the range of issues, which can be addressed in an IA framework. On the application front, the newly developed model has been applied to a selected set of studies to address policy related questions on climate change, in particular, the role of forestry, and land-use for historical greenhouse gas emissions; projections of future methane emissions; a research study related to energy implications of future stabilization of atmospheric CO{sub 2} content; and radiative forcing and estimation of a number of important greenhouse gases. In the following, the significant findings from the DOE supported study are outlined.
Date: May 30, 2000
Creator: Wuebbles, Donald J. & Atul, Jain
Partner: UNT Libraries Government Documents Department

Rhodopseudomonas palustris genome project. Final report

Description: Rhodopseudomonas palustris is a common soil and water bacterium that makes its living by converting sunlight to cellular energy and by absorbing atmospheric carbon dioxide and converting it to biomass. This microbe can also degrade and recycle components of the woody tissues of plants, wood being the most abundant polymer on earth. Because of its intimate involvement in carbon management and recycling, R. palustris was selected by the DOE Carbon Management Program to have its genome sequenced by the Joint Genome Institute (JGI). This award provided funds for the preparation of R. palustris genomic DNA which was then supplied to the JGI in sufficient amounts to enable the complete sequencing of the R. palustris genome. The PI also supplied the JGI with technical information about the molecular biology of R. palustris.
Date: November 22, 2000
Creator: Harwood, Caroline S.
Partner: UNT Libraries Government Documents Department

Terrestrial biogeochemical feedbacks in the climate system: from past to future

Description: The terrestrial biosphere plays a major role in the regulation of atmospheric composition, and hence climate, through multiple interlinked biogeochemical cycles (BGC). Ice-core and other palaeoenvironmental records show a fast response of vegetation cover and exchanges with the atmosphere to past climate change, although the phasing of these responses reflects spatial patterning and complex interactions between individual biospheric feedbacks. Modern observations show a similar responsiveness of terrestrial biogeochemical cycles to anthropogenically-forced climate changes and air pollution, with equally complex feedbacks. For future conditions, although carbon cycle-climate interactions have been a major focus, other BGC feedbacks could be as important in modulating climate changes. The additional radiative forcing from terrestrial BGC feedbacks other than those conventionally attributed to the carbon cycle is in the range of 0.6 to 1.6 Wm{sup -2}; all taken together we estimate a possible maximum of around 3 Wm{sup -2} towards the end of the 21st century. There are large uncertainties associated with these estimates but, given that the majority of BGC feedbacks result in a positive forcing because of the fundamental link between metabolic stimulation and increasing temperature, improved quantification of these feedbacks and their incorporation in earth system models is necessary in order to develop coherent plans to manage ecosystems for climate mitigation.
Date: January 5, 2010
Creator: Arneth, A.; Harrison, S. P.; Zaehle, S.; Tsigaridis, K; Menon, S; Bartlein, P.J. et al.
Partner: UNT Libraries Government Documents Department