scholarly journals The OceanFlux Greenhouse Gases methodology for deriving a sea surface climatology of CO<sub>2</sub> fugacity in support of air–sea gas flux studies

Ocean Science ◽  
2015 ◽  
Vol 11 (4) ◽  
pp. 519-541 ◽  
Author(s):  
L. M. Goddijn-Murphy ◽  
D. K. Woolf ◽  
P. E. Land ◽  
J. D. Shutler ◽  
C. Donlon
Keyword(s):  
Greenhouse Gases ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Sea Surface ◽  
Prediction Errors ◽  
Climate Variables ◽  
Gas Flux ◽  
Concentration Difference ◽  
Surface Measurements ◽  
Thermodynamic Driving Force

Abstract. Climatologies, or long-term averages, of essential climate variables are useful for evaluating models and providing a baseline for studying anomalies. The Surface Ocean CO2 Atlas (SOCAT) has made millions of global underway sea surface measurements of CO2 publicly available, all in a uniform format and presented as fugacity, fCO2. As fCO2 is highly sensitive to temperature, the measurements are only valid for the instantaneous sea surface temperature (SST) that is measured concurrently with the in-water CO2 measurement. To create a climatology of fCO2 data suitable for calculating air–sea CO2 fluxes, it is therefore desirable to calculate fCO2 valid for a more consistent and averaged SST. This paper presents the OceanFlux Greenhouse Gases methodology for creating such a climatology. We recomputed SOCAT's fCO2 values for their respective measurement month and year using monthly composite SST data on a 1° × 1° grid from satellite Earth observation and then extrapolated the resulting fCO2 values to reference year 2010. The data were then spatially interpolated onto a 1° × 1° grid of the global oceans to produce 12 monthly fCO2 distributions for 2010, including the prediction errors of fCO2 produced by the spatial interpolation technique. The partial pressure of CO2 (pCO2) is also provided for those who prefer to use pCO2. The CO2 concentration difference between ocean and atmosphere is the thermodynamic driving force of the air–sea CO2 flux, and hence the presented fCO2 distributions can be used in air–sea gas flux calculations together with climatologies of other climate variables.

scholarly journals Deriving a sea surface climatology of CO<sub>2</sub> fugacity in support of air–sea gas flux studies

2014 ◽  
Vol 11 (4) ◽  
pp. 1895-1948 ◽  
Author(s):  
L. M. Goddijn-Murphy ◽  
D. K. Woolf ◽  
P. E. Land ◽  
J. D. Shutler ◽  
C. Donlon
Keyword(s):  
Co2 Flux ◽  
Co2 Concentration ◽  
Sea Surface ◽  
Climate Variables ◽  
Gas Flux ◽  
Concentration Difference ◽  
Surface Measurements ◽  
Thermodynamic Driving Force ◽  
Ocean Carbon ◽  
Carbon Dioxide Co2

Abstract. Climatologies, or long-term averages, of essential climate variables are useful for evaluating models and providing a baseline for studying anomalies. The Surface Ocean Carbon Dioxide (CO2) Atlas (SOCAT) has made millions of global underway sea surface measurements of CO2 publicly available, all in a uniform format and presented as fugacity, fCO2. fCO2 is highly sensitive to temperature and the measurements are only valid for the instantaneous sea surface temperature (SST) that is measured concurrent with the in-water CO2 measurement. To create a climatology of fCO2 data suitable for calculating air–sea CO2 fluxes it is therefore desirable to calculate fCO2 valid for climate quality SST. This paper presents a method for creating such a climatology. We recomputed SOCAT's fCO2 values for their respective measurement month and year using climate quality SST data from satellite Earth observation and then extrapolated the resulting fCO2 values to reference year 2010. The data were then spatially interpolated onto a 1° × 1° grid of the global oceans to produce 12 monthly fCO2 distributions for 2010. The partial pressure of CO2 (pCO2) is also provided for those who prefer to use pCO2. The CO2 concentration difference between ocean and atmosphere is the thermodynamic driving force of the air–sea CO2 flux, and hence the presented fCO2 distributions can be used in air–sea gas flux calculations together with climatologies of other climate variables.

scholarly journals Uncertainties in wind speed dependent CO<sub>2</sub> transfer velocities due to airflow distortion at anemometer sites on ships

2010 ◽  
Vol 10 (11) ◽  
pp. 5123-5133 ◽  
Author(s):  
F. Griessbaum ◽  
B. I. Moat ◽  
Y. Narita ◽  
M. J. Yelland ◽  
O. Klemm ◽  
...  
Keyword(s):  
Wind Speed ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Gas Transfer ◽  
Co2 Uptake ◽  
Flow Distortion ◽  
Simulation Code ◽  
Transfer Velocity ◽  
Concentration Difference

Abstract. Data from platforms, research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterisations of the gas transfer velocity (k) and measurements of the difference between the partial pressures of CO2 in the ocean (pCO2 sw) and atmosphere (pCO2 atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s−1 to 15 m s−1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterisations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterisations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterisations are published. The estimates ranged from −4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterisations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterisations which are based on eddy covariance and deliberate tracer methods.

scholarly journals Uncertainties in wind speed dependent CO<sub>2</sub> transfer velocities due to airflow distortion at anemometer sites on ships

2009 ◽  
Vol 9 (5) ◽  
pp. 18839-18865
Author(s):  
F. Griessbaum ◽  
B. I. Moat ◽  
Y. Narita ◽  
M. J. Yelland ◽  
O. Klemm ◽  
...  
Keyword(s):  
Wind Speed ◽  
Three Dimensional ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Gas Transfer ◽  
Co2 Uptake ◽  
Flow Distortion ◽  
Simulation Code ◽  
Transfer Velocity ◽  
Concentration Difference

Abstract. Data from research vessels and merchant ships are used to estimate ocean CO2 uptake via parameterizations of the gas transfer velocity (k) and measurements of the difference between the concentration of CO2 in the ocean (pCO2sw) and atmosphere (pCO2atm) and of wind speed. Gas transfer velocities estimated using wind speed dependent parameterisations may be in error due to air flow distortion by the ship's hull and superstructure introducing biases into the measured wind speed. The effect of airflow distortion on estimates of the transfer velocity was examined by modelling the airflow around the three-dimensional geometries of the research vessels Hakuho Maru and Mirai, using the Large Eddy Simulation code GERRIS. For airflows within ±45° of the bow the maximum bias was +16%. For wind speed of 10 m s−1 to 15 m s−1, a +16% bias in wind speed would cause an overestimate in the calculated value of k of 30% to 50%, depending on which k parameterisation is used. This is due to the propagation of errors when using quadratic or cubic parameterizations. Recommendations for suitable anemometer locations on research vessels are given. The errors in transfer velocity may be much larger for typical merchant ships, as the anemometers are generally not as well-exposed as those on research vessels. Flow distortion may also introduce biases in the wind speed dependent k parameterizations themselves, since these are obtained by relating measurements of the CO2 flux to measurements of the wind speed and the CO2 concentration difference. To investigate this, flow distortion effects were estimated for three different platforms from which wind speed dependent parameterizations are published. The estimates ranged from –4% to +14% and showed that flow distortion may have a significant impact on wind speed dependent parameterizations. However, the wind biases are not large enough to explain the differences at high wind speeds in parameterizations which are based on eddy covariance and deliberate tracer methods.

scholarly journals CO2 flux behavior in the maritorium of San Andres Islands on 2019

Respuestas ◽  
2020 ◽  
Vol 25 (3) ◽  
Author(s):  
Juan Guillermo Popayán-Hernández ◽  
Orlando Zúñiga-Escobar
Keyword(s):  
Wind Speed ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Satellite Images ◽  
Co2 Flux ◽  
Sea Surface ◽  
Remote Sensors ◽  
Partial Pressures ◽  
Thermodynamic Relationship ◽  
San Andres

This document estimated the behavior of the CO2 flux in the San Andrés Islas maritime for the first half of 2019. This behavior was established based on the thermodynamic relationship between the sea surface temperature, the partial pressures of CO2 in the atmosphere and the water column, this from data derived from remote sensors. The satellite data were derived from the MODIS aqua sensors and the MERRA model for sea surface temperature and wind speed respectively. Satellite images were obtained from NASA databases, subsequently processed and specialized in ArcGis 10.1. Finally, the behavior of the CO2 flux is shown for the San Andrés Islas maritime, finding that it does not have a tendency to capture CO2, so acidification processes are discarded for the selected study period.

scholarly journals Biophsyical constraints on gross primary production by the terrestrial biosphere

2014 ◽  
Vol 11 (20) ◽  
pp. 5987-6001 ◽  
Author(s):  
H. Wang ◽  
I. C. Prentice ◽  
T. W. Davis
Keyword(s):  
Primary Production ◽  
Optimality Theory ◽  
Vegetation Cover ◽  
Gross Primary Production ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Water Shortage ◽  
C3 Plants ◽  
Environmental Controls ◽  
Green Vegetation

Abstract. Persistent divergences among the predictions of complex carbon-cycle models include differences in the sign as well as the magnitude of the response of global terrestrial primary production to climate change. Such problems with current models indicate an urgent need to reassess the principles underlying the environmental controls of primary production. The global patterns of annual and maximum monthly terrestrial gross primary production (GPP) by C3 plants are explored here using a simple first-principles model based on the light-use efficiency formalism and the Farquhar model for C3 photosynthesis. The model is driven by incident photosynthetically active radiation (PAR) and remotely sensed green-vegetation cover, with additional constraints imposed by low-temperature inhibition and CO2 limitation. The ratio of leaf-internal to ambient CO2 concentration in the model responds to growing-season mean temperature, atmospheric dryness (indexed by the cumulative water deficit, Δ E) and elevation, based on an optimality theory. The greatest annual GPP is predicted for tropical moist forests, but the maximum (summer) monthly GPP can be as high, or higher, in boreal or temperate forests. These findings are supported by a new analysis of CO2 flux measurements. The explanation is simply based on the seasonal and latitudinal distribution of PAR combined with the physiology of photosynthesis. By successively imposing biophysical constraints, it is shown that partial vegetation cover – driven primarily by water shortage – represents the largest constraint on global GPP.

scholarly journals Field Study on Correlation between CO2 Concentration and Surface Soil CO2 Flux in Closed Coal Mine Goaf

ACS Omega ◽  
2019 ◽  
Vol 4 (7) ◽  
pp. 12136-12145 ◽  
Author(s):  
Yongjun Wang ◽  
Xiaoming Zhang ◽  
Hemeng Zhang ◽  
Kyuro Sasaki
Keyword(s):  
Field Study ◽  
Coal Mine ◽  
Surface Soil ◽  
Co2 Flux ◽  
Co2 Concentration ◽  
Soil Co2 ◽  
Soil Co2 Flux

CO2 Flux Measurements over the Sea Surface by Eddy Correlation and Aerodynamic Techniques

2004 ◽  
Vol 60 (6) ◽  
pp. 995-1000 ◽  
Author(s):  
Toru Iwata ◽  
Keiko Yoshikawa ◽  
Katsutoshi Nishimura ◽  
Yoshihisa Higuchi ◽  
Takao Yamashita ◽  
...  
Keyword(s):  
Co2 Flux ◽  
Sea Surface ◽  
Eddy Correlation ◽  
Flux Measurements

scholarly journals Recent global CO<sub>2</sub> flux inferred from atmospheric CO<sub>2</sub> observations and its regional analyses

2011 ◽  
Vol 8 (11) ◽  
pp. 3263-3281 ◽  
Author(s):  
F. Deng ◽  
J. M. Chen
Keyword(s):  
North America ◽  
Interannual Variability ◽  
Co2 Flux ◽  
Terrestrial Ecosystems ◽  
Co2 Concentration ◽  
Climate Variations ◽  
Concentration Data ◽  
Surface Exchange ◽  
The North ◽  
Annual Means

Abstract. The net surface exchange of CO2 for the years 2002–2007 is inferred from 12 181 atmospheric CO2 concentration data with a time-dependent Bayesian synthesis inversion scheme. Monthly CO2 fluxes are optimized for 30 regions of the North America and 20 regions for the rest of the globe. Although there have been many previous multiyear inversion studies, the reliability of atmospheric inversion techniques has not yet been systematically evaluated for quantifying regional interannual variability in the carbon cycle. In this study, the global interannual variability of the CO2 flux is found to be dominated by terrestrial ecosystems, particularly by tropical land, and the variations of regional terrestrial carbon fluxes are closely related to climate variations. These interannual variations are mostly caused by abnormal meteorological conditions in a few months in the year or part of a growing season and cannot be well represented using annual means, suggesting that we should pay attention to finer temporal climate variations in ecosystem modeling. We find that, excluding fossil fuel and biomass burning emissions, terrestrial ecosystems and oceans absorb an average of 3.63 ± 0.49 and 1.94 ± 0.41 Pg C yr−1, respectively. The terrestrial uptake is mainly in northern land while the tropical and southern lands contribute 0.62 ± 0.47, and 0.67 ± 0.34 Pg C yr−1 to the sink, respectively. In North America, terrestrial ecosystems absorb 0.89 ± 0.18 Pg C yr−1 on average with a strong flux density found in the south-east of the continent.

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