Cropland carbon fluxes in the United States: increasing geospatial resolution of inventory-based carbon accounting

Inland water ecosystems dynamically process, transport, and sequester carbon. However, the transport of carbon through aquatic environments has not been quantitatively integrated in the context of terrestrial ecosystems. Here, we present the first integrated assessment, to our knowledge, of freshwater carbon fluxes for the conterminous United States, where 106 (range: 71–149) teragrams of carbon per year (TgC⋅y−1) is exported downstream or emitted to the atmosphere and sedimentation stores 21 (range: 9–65) TgC⋅y−1in lakes and reservoirs. We show that there is significant regional variation in aquatic carbon flux, but verify that emission across stream and river surfaces represents the dominant flux at 69 (range: 36–110) TgC⋅y−1or 65% of the total aquatic carbon flux for the conterminous United States. Comparing our results with the output of a suite of terrestrial biosphere models (TBMs), we suggest that within the current modeling framework, calculations of net ecosystem production (NEP) defined as terrestrial only may be overestimated by as much as 27%. However, the internal production and mineralization of carbon in freshwaters remain to be quantified and would reduce the effect of including aquatic carbon fluxes within calculations of terrestrial NEP. Reconciliation of carbon mass–flux interactions between terrestrial and aquatic carbon sources and sinks will require significant additional research and modeling capacity.

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An overview of the Fuel Characteristic Classification System — Quantifying, classifying, and creating fuelbeds for resource planningThis article is one of a selection of papers published in the Special Forum on the Fuel Characteristic Classification System.

Canadian Journal of Forest Research ◽

10.1139/x07-077 ◽

2007 ◽

Vol 37 (12) ◽

pp. 2383-2393 ◽

Cited By ~ 151

Author(s):

Roger D. Ottmar ◽

David V. Sandberg ◽

Cynthia L. Riccardi ◽

Susan J. Prichard

Keyword(s):

United States ◽

Classification System ◽

Treatment Effectiveness ◽

Fire Hazard ◽

Fire Behavior ◽

The United States ◽

Carbon Accounting ◽

Support Surface ◽

Fire Emissions ◽

Fuel Characteristic

We present an overview of the Fuel Characteristic Classification System (FCCS), a tool that enables land managers, regulators, and scientists to create and catalogue fuelbeds and to classify those fuelbeds for their capacity to support fire and consume fuels. The fuelbed characteristics and fire classification from this tool will provide inputs for current and future sophisticated models for the quantification of fire behavior, fire effects, and carbon accounting and enable assessment of fuel treatment effectiveness. The system was designed from requirements provided by land managers, scientists, and policy makers gathered through six regional workshops. The FCCS contains a set of fuelbeds representing the United States, which were compiled from scientific literature, fuels photo series, fuels data sets, and expert opinion. The system enables modification and enhancement of these fuelbeds to represent a particular scale of interest. The FCCS then reports assigned and calculated fuel characteristics for each existing fuelbed stratum including the canopy, shrubs, nonwoody, woody, litter–lichen–moss, and duff. Finally, the system classifies each fuelbed by calculating fire potentials that provide an index of the intrinsic capacity of each fuelbed to support surface fire behavior, support crown fire, and provide fuels for flaming, smoldering, and residual consumption. The FCCS outputs are being used in a national wildland fire emissions inventory and in the development of fuelbed, fire hazard, and treatment effectiveness maps on several national forests. Although the FCCS was built for the United States, the conceptual framework is applicable worldwide.

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A regional high-resolution carbon flux inversion of North America for 2004

Biogeosciences ◽

10.5194/bg-7-1625-2010 ◽

2010 ◽

Vol 7 (5) ◽

pp. 1625-1644 ◽

Cited By ~ 89

Author(s):

A. E. Schuh ◽

A. S. Denning ◽

K. D. Corbin ◽

I. T. Baker ◽

M. Uliasz ◽

...

Keyword(s):

United States ◽

High Resolution ◽

North America ◽

Carbon Flux ◽

Ecosystem Respiration ◽

Carbon Fluxes ◽

The United States ◽

Mixing Ratio ◽

South Central ◽

Ratio Data

Abstract. Resolving the discrepancies between NEE estimates based upon (1) ground studies and (2) atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS) and an underlying biosphere (SiB3) model, both running on an identical 40 km grid over most of North America. Current operational systems like CarbonTracker as well as many previous global inversions including the Transcom suite of inversions have utilized inversion regions formed by collapsing biome-similar grid cells into larger aggregated regions. An extreme example of this might be where corrections to NEE imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to Gross Primary Productivity (GPP) and Ecosystem Respiration (ER) is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the Parameterized Chemical Transport Model (PCTM) models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America. We perform the inversion with two independently derived boundary inflow conditions and calculate jackknife-based statistics to test the robustness of the model results. We then compare final results to estimates obtained from the CarbonTracker inversion system and at the Southern Great Plains flux site. Results are promising, showing the ability to correct carbon fluxes from the biosphere models over annual and seasonal time scales, as well as over the different GPP and ER components. Additionally, the correlation of an estimated sink of carbon in the South Central United States with regional anomalously high precipitation in an area of managed agricultural and forest lands provides interesting hypotheses for future work.

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Terrestrial Carbon Sinks for the United States Predicted from MODIS Satellite Data and Ecosystem Modeling

Earth Interactions ◽

10.1175/ei228.1 ◽

2007 ◽

Vol 11 (13) ◽

pp. 1-21 ◽

Cited By ~ 58

Author(s):

Christopher Potter ◽

Steven Klooster ◽

Alfredo Huete ◽

Vanessa Genovese

Keyword(s):

United States ◽

Pacific Northwest ◽

Vegetation Index ◽

Net Primary Production ◽

Regional Climate ◽

Terrestrial Ecosystems ◽

Carbon Fluxes ◽

The United States ◽

Carbon Sinks ◽

Modis Evi

Abstract A simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate monthly carbon fluxes in terrestrial ecosystems of the conterminous United States over the period 2001–04. Predicted net ecosystem production (NEP) flux for atmospheric CO2 in the United States was estimated as annual net sink of about +0.2 Pg C in 2004. Regional climate patterns were reflected in the predicted annual NEP flux from the model, which showed extensive carbon sinks in ecosystems of the southern and eastern regions in 2003–04, and major carbon source fluxes from ecosystems in the Rocky Mountain and Pacific Northwest regions in 2003–04. As demonstrated through tower site comparisons, net primary production (NPP) modeled with monthly MODIS enhanced vegetation index (EVI) inputs closely resembles both the measured high- and low-season carbon fluxes. Modeling results suggest that the capacity of the NASA Carnegie Ames Stanford Approach (CASA) model to use 8-km resolution MODIS EVI data to predict peak growing season uptake rates of CO2 in irrigated croplands and moist temperate forests is strong.

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A regional high-resolution carbon flux inversion of North America for 2004

Biogeosciences Discussions ◽

10.5194/bgd-6-10195-2009 ◽

2009 ◽

Vol 6 (6) ◽

pp. 10195-10241 ◽

Cited By ~ 1

Author(s):

A. E. Schuh ◽

A. S. Denning ◽

K. D. Corbin ◽

I. T. Baker ◽

M. Uliasz ◽

...

Keyword(s):

United States ◽

High Resolution ◽

North America ◽

Carbon Flux ◽

Transport Model ◽

Ecosystem Respiration ◽

Carbon Fluxes ◽

The United States ◽

Mixing Ratio ◽

Ratio Data

Abstract. Resolving the discrepancies between NEE estimates based upon (1) ground studies and (2) atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS) and an underlying biosphere (SiB3) model, both running on an identical 40 km grid over most of North America. Previous papers have utilized inversion regions formed by collapsing biome-similar grid cells into large aggregated regions. The effect of this is that the NEE correction imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to gross primary productivity (GPP) and ecosystem respiration (ER) is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the parameterized chemical transport model (PCTM) models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America. We perform the inversion with two independently derived boundary inflow conditions and calculate jackknife-based statistics to test the robustness of the model results. We then compare final results to estimates obtained from the CarbonTracker inversion system and the Ameriflux network. Results are promising, showing the ability to correct carbon fluxes from the biosphere models over annual and seasonal time scales, as well as over the different GPP and ER components, and also providing interesting hypotheses for future work.

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Party Strength in the United States: Some Corrections

The Journal of Politics ◽

10.1017/s0022381600041591 ◽

1975 ◽

Vol 37 (2) ◽

pp. 641-642 ◽

Cited By ~ 1

Author(s):

Paul T. David

Keyword(s):

United States ◽

The United States ◽

Party Strength

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Correlative microscopy in distrubuted (client/server) computing environments: tools for catalyzing the rapid dissemination of information about the cell biology of the human prostate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139780 ◽

1995 ◽

Vol 53 ◽

pp. 682-683

Author(s):

A. Hakam ◽

J.T. Gau ◽

M.L. Grove ◽

B.A. Evans ◽

M. Shuman ◽

...

Keyword(s):

United States ◽

Cell Biology ◽

Tissue Bank ◽

The United States ◽

Prostate Adenocarcinoma ◽

Correlative Microscopy ◽

Client Server ◽

Critical Elements ◽

Transplant Organ

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.

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Digital image acquisition, processing, and analysis in a polymer microscopy laboratory

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170001 ◽

1994 ◽

Vol 52 ◽

pp. 454-455

Author(s):

Vinod K. Berry ◽

Xiao Zhang

Keyword(s):

United States ◽

Image Analysis ◽

Digital Image ◽

Image Acquisition ◽

Image Transmission ◽

The United States ◽

Quantitative Image Analysis ◽

Quantitative Image

In recent years it became apparent that we needed to improve productivity and efficiency in the Microscopy Laboratories in GE Plastics. It was realized that digital image acquisition, archiving, processing, analysis, and transmission over a network would be the best way to achieve this goal. Also, the capabilities of quantitative image analysis, image transmission etc. available with this approach would help us to increase our efficiency. Although the advantages of digital image acquisition, processing, archiving, etc. have been described and are being practiced in many SEM, laboratories, they have not been generally applied in microscopy laboratories (TEM, Optical, SEM and others) and impact on increased productivity has not been yet exploited as well.In order to attain our objective we have acquired a SEMICAPS imaging workstation for each of the GE Plastic sites in the United States. We have integrated the workstation with the microscopes and their peripherals as shown in Figure 1.

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Silence of the Land: On the Historical Irrelevance of Territory to Congressional Districting and Political Representation in the United States

Studies in American Political Development ◽

10.1017/s0898588x01010045 ◽

2001 ◽

Vol 15 (01) ◽

pp. 53-87 ◽

Cited By ~ 2

Author(s):

Andrew Rehfeld

Keyword(s):

United States ◽

House Of Representatives ◽

Political Representation ◽

The United States ◽

Representative Government ◽

Congressional District ◽

Congressional Districts ◽

Communities Of Interest

Every ten years, the United States “constructs” itself politically. On a decennial basis, U.S. Congressional districts are quite literally drawn, physically constructing political representation in the House of Representatives on the basis of where one lives. Why does the United States do it this way? What justifies domicile as the sole criteria of constituency construction? These are the questions raised in this article. Contrary to many contemporary understandings of representation at the founding, I argue that there were no principled reasons for using domicile as the method of organizing for political representation. Even in 1787, the Congressional district was expected to be far too large to map onto existing communities of interest. Instead, territory should be understood as forming a habit of mind for the founders, even while it was necessary to achieve other democratic aims of representative government.

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