A compilation of sulfur dioxide and carbon dioxide emission-rate data from Mount St. Helens during 1980-88
Airborne monitoring of Mount St. Helens by the USGS began in May 1980 for sulfur dioxide emissions and in July 1980 for carbon dioxide emissions. A correlation spectrometer, or COSPEC, was used to measure sulfur dioxide in Mount St. Helens' plume. The upward-looking COSPEC was mounted in a fixed-wing aircraft and flown below and at right angles to the plume. Typically, three to six traverses were made underneath the plume to determine the SO2 burden (concentration x pathlength) within a cross-section of the plume. Knowing the burden along with the plume width and plume velocity (assumed to be the same as ambient wind speed), we could then calculate the emission rate of SO2. The use of correlation spectroscopy for determining the sulfur dioxide output of volcanoes is well established and the technique has been discussed in detail by a number of investigators (Malinconico, 1979; Casadevall and others, 1981; Stoiber and others, 1983). Carbon dioxide in the Mount St. Helens plume was measured by an infrared spectrometer tuned to the 4.26 um CO2 absorption band. An external sample tube was attached to the fuselage of a twin-engine aircraft to deliver outside air to the gas cell of the spectrometer. The aircraft was then flown at several different elevations through the plume at right angles to plume trajectory to define plume area and carbon dioxide concentration in a vertical cross-section of the plume. These two parameters along with the density of CO2 for the altitude of the plume and the plume velocity (assumed as above to be equal to ambient wind speed) were then used to calculate the CO2 emission rate (Harris and others, 1981).
123
- 10.1126/science.221.4618.1383
- Jan 1, 1983
- Science
100
- 10.1038/278043a0
- Mar 1, 1979
- Nature
21
- 10.1007/bf00302825
- Jan 1, 1994
- Bulletin of Volcanology
35
- 10.1016/0377-0273(92)90127-y
- Jul 1, 1992
- Journal of Volcanology and Geothermal Research
- Research Article
239
- 10.2138/rmg.2011.73.8
- Jan 1, 2011
- Reviews in Mineralogy and Geochemistry
Research Article| January 01, 2011 The Sulfur Budget in Magmas: Evidence from Melt Inclusions, Submarine Glasses, and Volcanic Gas Emissions Paul J. Wallace; Paul J. Wallace Deprtment of Geological Sciences, University of Oregon Eugene, Oregon 97403-1272, U.S.A., pwallace@uoregon.edu Search for other works by this author on: GSW Google Scholar Marie Edmonds Marie Edmonds Department of Earth Sciences University of Cambridge Cambridge, CB2 3EQ, United Kingdom, medm06@esc.cam.ac.uk Search for other works by this author on: GSW Google Scholar Author and Article Information Paul J. Wallace Deprtment of Geological Sciences, University of Oregon Eugene, Oregon 97403-1272, U.S.A., pwallace@uoregon.edu Marie Edmonds Department of Earth Sciences University of Cambridge Cambridge, CB2 3EQ, United Kingdom, medm06@esc.cam.ac.uk Publisher: Mineralogical Society of America First Online: 09 Mar 2017 © The Mineralogical Society Of America Reviews in Mineralogy and Geochemistry (2011) 73 (1): 215–246. https://doi.org/10.2138/rmg.2011.73.8 Article history First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Paul J. Wallace, Marie Edmonds; The Sulfur Budget in Magmas: Evidence from Melt Inclusions, Submarine Glasses, and Volcanic Gas Emissions. Reviews in Mineralogy and Geochemistry 2011;; 73 (1): 215–246. doi: https://doi.org/10.2138/rmg.2011.73.8 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyReviews in Mineralogy and Geochemistry Search Advanced Search The major magmatic volatile components—H2O, CO2, S, Cl, and F— play an important role in the formation, evolution, and eruption of magma. Knowledge of magmatic concentrations and fluxes of these volatiles is thus important for understanding explosive eruptive behavior of volcanoes, recycling of volatiles in subduction zones, formation of magmatic-hydrothermal ore deposits, fluxes of volcanic gases to Earth’s atmosphere, and potential climatic impacts of large volcanic eruptions. Over the past 30 years, new analytical techniques for measuring volatiles in melt inclusions and glasses from volcanic rocks and new developments in remote sensing technology used for quantifying... You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
- Research Article
71
- 10.1029/94gl02761
- Dec 15, 1994
- Geophysical Research Letters
SO2 from explosive volcanism can cause significant climatic and atmospheric impacts, but the source of the sulfur is controversial. TOMS, COSPEC, and ash leachate data for Mount St. Helens from the time of the climactic eruption on 18 May 1980 to the final stages of non‐explosive degassing in 1988 give a total SO2 emission of 2 Mt. COSPEC data show a sharp drop in emission rate that was apparently controlled by a decreasing rate of magma supply. A total SO2 emission of only 0.08 Mt is estimated from melt inclusion data and the conventional assumption that the main sulfur source was pre‐eruption melt; commonly invoked sources of “excess sulfur” (anhydrite decomposition, basaltic magma, and degassing of non‐erupted magma) are unlikely in this case. Thus melt inclusions may significantly underestimate SO2 emissions and impacts of explosive volcanism on climate and the atmosphere. Measured CO2 emissions, together with the H2O content of melt inclusions and experimental solubility data, indicate the Mount St. Helens dacite was vapor‐saturated at depth prior to ascent and suggest that a vapor phase was the main source of sulfur for the 2‐Mt of SO2. A vapor source is consistent with experimental studies on the Mount St. Helens dacite and removes the need for a much debated shallow magma body.
- Research Article
39
- 10.1016/j.epsl.2006.07.018
- Aug 17, 2006
- Earth and Planetary Science Letters
Tracing pre-eruptive magma degassing using ( 210Pb/ 226Ra) disequilibria in the volcanic deposits of the 1980–1986 eruption of Mount St. Helens
- Research Article
95
- 10.1016/j.jvolgeores.2012.04.012
- Apr 12, 2012
- Journal of Volcanology and Geothermal Research
Degassing of CO2, SO2, and H2S associated with the 2009 eruption of Redoubt Volcano, Alaska
- Research Article
32
- 10.1029/2010jb007924
- Aug 23, 2011
- Journal of Geophysical Research
[1] Multiplets, or groups of earthquakes with similar waveforms, are commonly observed at volcanoes, particularly those exhibiting unrest. Using triggered seismic data from the 1980–1986 Mount St. Helens (MSH) eruption, we have constructed a catalog of multiplet occurrence. Our analysis reveals that the occurrence of multiplets is related, at least in part, to the viscosity of the magma. We also constructed catalogs of multiplet occurrence using continuous seismic data from the 2004 eruption at MSH and 2007 eruption at Bezymianny Volcano, Russia. Prior to explosions at MSH in 2004 and Bezymianny in 2007, the multiplet proportion of total seismicity (MPTS) declined, while the average amplitudes and standard deviations of the average amplitude increased. The life spans of multiplets (time between the first and last event) were also shorter prior to explosions than during passive lava extrusion. Dome-forming eruptions that include a partially solidified plug, like MSH (1983–1986 and 2004–2008), often possess multiplets with longer life spans and MPTS values exceeding 50%. Conceptually, the relatively unstable environment prior to explosions is characterized by large and variable stress gradients brought about by rapidly changing overpressures within the conduit. We infer that such complex stress fields affect the number of concurrent families, MPTS, average amplitude, and standard deviation of the amplitude of the multiplets. We also argue that multiplet detection may be an important new monitoring tool for determining the timing of explosions and in forecasting the type of eruption.
- Report Component
28
- 10.3133/sir20085114
- Jan 1, 2008
Instrumentation recommendations for volcano monitoring at U.S. volcanoes under the national volcano early warning system
- Research Article
269
- 10.2138/rmg.2008.69.6
- Jan 1, 2008
- Reviews in Mineralogy and Geochemistry
Explosive volcanic eruptions constitute a major class of natural hazard with potentially profound economic and societal consequences. Although such eruptions cannot be prevented and only rarely may be anticipated with any degree of accuracy, better understanding of how explosive volcanoes work will lead to improved volcano monitoring and disaster mitigation. A major goal of modern volcanology is linking of surface-monitored signals from active volcanoes, such as seismicity, ground deformation and gas chemistry, to the subterranean processes that generate them. Because sub-volcanic systems cannot be accessed directly, most of what we know about these systems comes from studies of erupted products. Such studies shed light on what happens underground prior to and during eruptions, thereby providing an interpretative framework for post hoc evaluation of monitoring data. The aim of this review is to present some of the current petrological techniques that can be used for studying eruptive products and for constraining key magmatic variables such as pressure, temperature, and volatile content. We first review analytical techniques, paying particular attention to pitfalls and strategies for analyzing volcanic samples. We then examine commonly used geothermometry schemes, evaluating each by comparison with experimental data not used in the original geothermometer calibrations. As there are few mineral-based geobarometers applicable to magma storage regions, we review other methods used to determine pre-eruptive magma equilibration pressures. We then demonstrate how petrologically-constrained parameters can be compared to the contemporaneous monitoring record. These examples are drawn largely from Mount St. Helens volcano, for which there are abundant petrological and monitoring data. However, we emphasize that our approaches can be applied to any number of active volcanoes worldwide. Finally, we illustrate the application of these techniques to two different types of magmatic systems—large silicic magma chambers and small intermediate-composition magma storage regions—with particular focus on the combined evolution of melt …
- Research Article
50
- 10.1029/95gl01319
- Jul 1, 1995
- Geophysical Research Letters
The discharge rate of SO2 from Unzen volcano, which started erupting in November 1990, has been measured with a correlation spectrometer (COSPEC) at a fixed ground‐based station about 2.3 km SSW from the summit lava dome. The discharge rate of SO2 increased greatly after the explosive eruptions on June 8th and 11th, 1991. High discharge rates of SO2 (an average of 180 ton/day) were observed from July 1991 to January 1992, followed by a general decrease to an average of 110 ton/day during March 1992 and May 1994. The discharge rate of SO2 correlates with the extrusion rate of magma. Judging from the sulfur inventory, i.e., 130–450 g of discharged SO2 per ton of erupted magma, and the sulfur content of the extruded lava, the proportion of sulfur degassed from the magma is estimated to be ca. 80%, suggesting an efficient volatile degassing. The discharge rate of the total volatiles is calculated to be 7,700 ton/day by combining the SO2 discharge rate with the chemical composition of volcanic gases.
- Report Component
1
- 10.3133/ofr97692
- Jan 1, 1997
Publications of the Volcano Hazards Program 1994-1996
- Research Article
10
- 10.1029/2010eo190001
- May 11, 2010
- Eos, Transactions American Geophysical Union
The spectacular eruption of Mount St. Helens on 18 May 1980 electrified scientists and the public. Photodocumentation of the colossal landslide, directed blast, and ensuing eruption column—which reached as high as 25 kilometers in altitude and lasted for nearly 9 hours—made news worldwide. Reconnaissance of the devastation spurred efforts to understand the power and awe of those moments (Figure 1).The eruption remains a seminal historical event—studying it and its aftermath revolutionized the way scientists approach the field of volcanology. Not only was the eruption spectacular, but also it occurred in daytime, at an accessible volcano, in a country with the resources to transform disaster into scientific opportunity, amid a transformation in digital technology. Lives lost and the impact of the eruption on people and infrastructure downstream and downwind made it imperative for scientists to investigate events and work with communities to lessen losses from future eruptions.
- Research Article
47
- 10.1016/0377-0273(94)90050-7
- Aug 1, 1994
- Journal of Volcanology and Geothermal Research
Emission rates of sulfur dioxide and carbon dioxide from Redoubt Volcano, Alaska during the 1989–1990 eruptions
- Conference Article
8
- 10.2118/35848-ms
- Jun 9, 1996
The technology of disposing acid gas in subsurface formations is relatively new. In the past two years, this technology has been used increasingly by Alberta producers to handle small and uneconomic volume of acid gas. Prior to 1994, there was only one scheme in operation. at the end of 1995, 19 disposal schemes were operating or in the process of construction. PanCanadian Petroleum made a Nisku oil discovery in 1993 at Wayne-Rosedale, Alberta. In order to proceed with pool development and produce the reserves economically, a sulphur handling scheme had to be in place. The scheme chosen was subsurface acid gas disposal. Information on disposal technology available during the conceptual and design stages of this project was very limited with respect to published literature and operating experience. This paper is written to provide the reader with some details of the scheme and an overview of the steps taken to execute the project from conceptual evaluation to regulatory submission to start up and operation. The safety measures that PanCanadian has taken to ensure a safe operation are discussed. Introduction PanCanadian Petroleum made a Nisku oil discovery in the Wayne-Rosedale area, located approximately 100 kilometres northeast of Calgary, Alberta (see Figure 1) in October, 1993. The Wayne-Rosedale D2A Pool produces a 340 API oil with its associated solution gas containing 4 % hydrogen sulphide (H2S) and 17 % carbon dioxide (CO2). Subsequent delineation and development drilling indicated the pool has an estimated reserves of some 2.5 106m3 of oil and 250 106m3 of raw associated solution gas. To exploit these reserves economically, sour processing facilities would be required in this environmentally sensitive area. As shown in Figure 1, the pool and facilities are within 4 kilometers of Horseshoe Canyon, a very popular scenic view point that attracts many local residences and visitors. In 1988 the Alberta Energy Conservation Board (ERCB, now Energy Utilities Board - (EUB)) issued Information Letter (IL) 88-13 outlining a set of guidelines for sulphur recovery in sour gas plants. These guidelines stipulated that a gas plant with a sulphur throughput between 5 to 10 tonnes per day (Wayne-Rosedale was estimated at 5 tonnes per day sulphur) had to recover 90% of that sulphur. Even with sulphur recovery, the tail gas containing the remaining 10 percent sulphur and carbon dioxide still would have to be incinerated and the sulphur dioxide (SO2) and carbon dioxide would still be emitted to the atmosphere. The development project proceeded with the construction of an oil battery, gathering satellite, gas plant with sweetening facilities and an acid gas disposal scheme with a disposal well, compressor and a dehydration unit. The oil battery and gas plant came on stream in July 1995 with the acid gas disposal scheme commencing operations in December 1995. A Schematic of the facilities is shown in Figure 2. Evaluation of Sulphur Handling Scheme To meet regulatory requirements and satisfy public expectations on sulphur emission, some form of sulphur emission reduction was needed. The composition of the solution gas from the Wayne-Rosedale D2A Pool is summarized in Table 1. The estimated average daily solution gas production rate was approximately 100 103m3/d resulting in about 21 10m3/d of acid gas. In early 1994, a multi-discipline team (consisting of reservoir engineering, production engineering, geology, facility engineering and operation engineering personnel) were charged to develop a viable acid gas handling scheme. The options that the team evaluated were sulphur recovery, incineration, third party processing and subsurface disposal. P. 691
- Report Component
10
- 10.3133/ofr9555
- Jan 1, 1995
This report contains all of the available daily sulfur dioxide and carbon dioxide emission rates from Cook Inlet volcanoes as determined by the U.S. Geological Survey (USGS) from March 1990 through July 1994. Airborne sulfur dioxide gas sampling of the Cook Inlet volcanoes (Redoubt, Spurr, Iliamna, and Augustine) began in 1986 when several measurements were carried out at Augustine volcano during the eruption of 1986. Systematic monitoring for sulfur dioxide and carbon dioxide began in March 1990 at Redoubt volcano and continues to the present. Intermittent measurements at Augustine and Iliamna volcanoes began in 1990 and continues to the present. Intermittent measurements began at Spurr volcano in 1991, and were continued at more regular intervals from June, 1992 through the 1992 eruption at the Crater Peak vent to the present.
- Research Article
5
- 10.1016/1352-2310(96)00004-0
- Sep 1, 1996
- Atmospheric Environment
Characteristics of the large-scale circulation during episodes with high and low concentrations of carbon dioxide and air pollutants at an arctic monitoring site in winter
- Research Article
46
- 10.1016/s0009-2541(00)00391-0
- Jun 8, 2001
- Chemical Geology
White Island volcano, New Zealand: carbon dioxide and sulfur dioxide emission rates and melt inclusion studies
- Preprint Article
- 10.5194/egusphere-egu2020-10712
- Mar 23, 2020
<p>Bagana volcano, Papua New Guinea, is among Earth’s youngest and most active volcanoes. Bagana typically exhibits multi-year episodes of lava extrusion, interspersed with pause periods characterised by strong passive degassing. Based on satellite-based observations, Bagana is the third ranked global source of volcanic sulfur dioxide over the past 15 years. Recent work based on global correlations between volcanic gas composition and magma trace element chemistry has predicted that it may be the fifth ranked global volcanic deep carbon source. However, this indirect estimate of Bagana’s potential carbon budget has yet to be ground-truthed by in-situ sampling.</p><p>We visited Bagana in September 2019 and made the first measurements of the chemical composition of the volcano’s summit gas plume. We placed a miniaturized MultiGAS sensor array on board an unoccupied aerial system (UAS, or drone) and flew the sensors through the plume. Our aircraft flew beyond visual line of sight, reaching the gas plume from around 7 km horizontal distance and 2 km altitude below the summit. Such long-range UAS flights offer immense potential for studying gas emissions from such steep, active or remote volcanoes.</p><p>Our MultiGAS flights found relatively low concentrations of both sulfur dioxide and carbon dioxide in the Bagana plume. Moreover, we made coincident remote sensing measurements of sulfur dioxide emissions using ground- and UAS-based ultraviolet spectroscopy and calculated SO2 fluxes of only ~400 tonnes per day. These are an order of magnitude below the typical fluxes inferred from satellite observations. Combining MultiGAS plume composition (CO2/SO2 molar ratio, mean ~3.4) and SO2 fluxes allow us to estimate Bagana’s CO2 flux into the atmosphere as only ~1360 t/d.</p><p>Our interpretation of these results is that the volcano is presently in a low state of activity. From satellite observations, we note the cessation of the most recent extrusive episode several weeks prior to our field campaign. The lack of the anticipated strong passive degassing often observed by spaceborne UV sensors is likely a result of “scrubbing” in the volcanic edifice, where rising gases interact with groundwater, resulting in dissolution of sulfur species into the groundwater and perhaps precipitation of sulfur-bearing minerals into edifice fractures. As the volcano moves towards a future extrusive episode, we might anticipate the gradual drying out of the hydrothermal system and a shift towards more truly magmatic gas compositions. Our results show that short campaign measurements may not provide data which are representative of a volcano’s longterm behaviour and we suggest that caution is needed in using such data to calculate or extrapolate regional and global volatile emissions inventories.</p>
- Research Article
4
- 10.1190/int-2017-0025.1
- Oct 23, 2017
- Interpretation
Managing impure carbon dioxide produced by fossil fuel-based generation of electricity is required for successful implementation of carbon capture, utilization, and storage. Impurities in carbon dioxide, particularly [Formula: see text] and [Formula: see text], are geochemically more reactive than the carbon dioxide and may adversely impact a carbon dioxide storage reservoir by generating additional acidity. Hydrothermal experiments are performed to evaluate geochemical and mineralogic effects of injecting [Formula: see text]-[Formula: see text] fluid into a carbonate reservoir. The experimental design is based on a natural carbon dioxide reservoir, the Madison Limestone on the Moxa Arch of Southwest Wyoming, which serves as a natural analog for geologic cosequestration of sulfur dioxide and carbon dioxide. Idealized Madison Limestone ([Formula: see text]) and [Formula: see text] brine ([Formula: see text], initial [Formula: see text]) reacted at reservoir conditions (110°C and 25 MPa) for approximately 165 days (3960 h). Carbon dioxide fluid containing 500 ppmv sulfur dioxide was injected and the experiment continued for approximately 55 days (1326 h). Sulfur dioxide partitions out of the supercritical carbon dioxide phase and dissolves into coexisting brine on the time scale of the experiments (55 days). Injecting supercritical [Formula: see text]-[Formula: see text] or pure supercritical carbon dioxide into a brine-limestone system produces the same in situ pH (4.6) and ex situ pH (6.4–6.5), as measured 28 h after injection because dissolution of calcite buffers in situ pH. Precipitation of anhydrite sequesters injected sulfur and, coupled with dissolution of calcite, effectively buffers the amount of dissolved calcium to the same concentrations measured in limestone-brine experiments injected with pure carbon dioxide. Supercritical [Formula: see text]-[Formula: see text] does not enhance the sequestration potential of a carbonate reservoir relative to pure supercritical carbon dioxide. Our results substantiate predictions from natural analog studies of the Madison Limestone that anhydrite traps sulfur and carbonate minerals ultimately reprecipitate and mineralize carbon in carbonate reservoirs.
- Research Article
- 10.5344/ajev.1960.11.1.35
- Jan 1, 1960
- American Journal of Enology and Viticulture
The literature relating to the problem of low-level carbonation of wines was reviewed. The inherent difficulties in the current method of carbon dioxide determination in wines were studied and discussed. The greatest source of error was found to be due to the sulfur dioxide content. Modification of the method were suggested to eliminate the sources of error arising from the sulfur dioxide and volatile acid content of the wines. Study of the various factors influencing the degree of carbonation gave the following effects and relationships: (a) Carbonator gauge pressure, at pressures between 8 and 20 lbs. per square inch, bears a straight-line relationship to the carbon dioxide content of the carbonated wine. (b) Total soluble solids affect carbon dioxide content. Generally, the higher the total soluble solids the lower the carbon dioxide retention. This requires an increased carbonator gauge pressure if a fixed carbon dioxide content is desired. (c) Ethyl alcohol in the range of 12 to 20 percent has less effect on carbon dioxide content. The amount of carbon dioxide absorption was slightly reduced by increasing alcohol concentration in the above range. (d) With constant carbonator gauge pressure, carbon dioxide retention by wine decreases with increasing temperature.
- Preprint Article
- 10.32920/ryerson.14657961
- Jun 8, 2021
Diffusivity is a strong function of concentration and an important transport property. Diffusion of multiple species is far more frequent than the diffusion of one species. However, there are limited experimental data available on multi-component diffusivity. The objective of this study is to develop an optimal control framework to determine multi-component concentration-dependent diffusivities of two gases in a non-volatile phase such as polymer. In Part 1 of this study, we derived a detailed mass-transfer model of the experimental diffusion process for the non-volatile phase to provide the temporal masses of gases in the polymer. The determination of diffusivities is an inverse problem involving principles of optimal control. Necessary conditions are determined to solve this problem. In Part 2 of this study, we utilized the results of Part 1 to determine the concentration-dependent, multi-component diffusivities of nitrogen and carbon dioxide in polystyrene. To that end, solubility and diffusion experiments are conducted to obtain necessary data. In the ternary system of nitrogen (1), carbon dioxide (2), and polystyrene (3), the diffusivities and D11, D12, D21, and D22 versus the gas mass fractions are two-dimensional surfaces. The diffusivity of carbon dioxide was found to be greater than that of nitrogen. The value of the main diffusion coefficient D11 was found to increase as the concentration of carbon dioxide increased. The highest value of D11 obtained was 2.2 X 10^-8m^2s^-1 for nitrogen mass fraction of 3.14 X10^-4 and for a carbon dioxide mass fraction of 5.67 X 10^-4 . The cross-diffusion coefficient increased as the concentrations of nitrogen and carbon dioxide increased. The diffusivity reached its maximum value when the concentrations of nitrogen and carbon dioxide were at their maximum values. The diffusivity was of the order of 10^-9m^2s^-1. The diffusivity of the cross-diffusion coefficient D21 was found to be increased for the mass The diffusivity of the cross-diffusion coefficient was found to be increased for the mass fractions of carbon dioxide ranging from 0 to 1.70 X 10^-3 . The diffusivity was found to be of the order of . The diffusion coefficient, D22, was found to increase with the concentrations of nitrogen and carbon dioxide, D22 remained high with low concentrations of carbon dioxide. The diffusivity was found to be of the order of 10^-7m^2s^-1
- Preprint Article
- 10.32920/ryerson.14657961.v1
- Jun 8, 2021
Diffusivity is a strong function of concentration and an important transport property. Diffusion of multiple species is far more frequent than the diffusion of one species. However, there are limited experimental data available on multi-component diffusivity. The objective of this study is to develop an optimal control framework to determine multi-component concentration-dependent diffusivities of two gases in a non-volatile phase such as polymer. In Part 1 of this study, we derived a detailed mass-transfer model of the experimental diffusion process for the non-volatile phase to provide the temporal masses of gases in the polymer. The determination of diffusivities is an inverse problem involving principles of optimal control. Necessary conditions are determined to solve this problem. In Part 2 of this study, we utilized the results of Part 1 to determine the concentration-dependent, multi-component diffusivities of nitrogen and carbon dioxide in polystyrene. To that end, solubility and diffusion experiments are conducted to obtain necessary data. In the ternary system of nitrogen (1), carbon dioxide (2), and polystyrene (3), the diffusivities and D11, D12, D21, and D22 versus the gas mass fractions are two-dimensional surfaces. The diffusivity of carbon dioxide was found to be greater than that of nitrogen. The value of the main diffusion coefficient D11 was found to increase as the concentration of carbon dioxide increased. The highest value of D11 obtained was 2.2 X 10^-8m^2s^-1 for nitrogen mass fraction of 3.14 X10^-4 and for a carbon dioxide mass fraction of 5.67 X 10^-4 . The cross-diffusion coefficient increased as the concentrations of nitrogen and carbon dioxide increased. The diffusivity reached its maximum value when the concentrations of nitrogen and carbon dioxide were at their maximum values. The diffusivity was of the order of 10^-9m^2s^-1. The diffusivity of the cross-diffusion coefficient D21 was found to be increased for the mass The diffusivity of the cross-diffusion coefficient was found to be increased for the mass fractions of carbon dioxide ranging from 0 to 1.70 X 10^-3 . The diffusivity was found to be of the order of . The diffusion coefficient, D22, was found to increase with the concentrations of nitrogen and carbon dioxide, D22 remained high with low concentrations of carbon dioxide. The diffusivity was found to be of the order of 10^-7m^2s^-1
- Research Article
9
- 10.1360/tb-2019-0022
- Nov 19, 2019
- Chinese Science Bulletin
The increase in carbon dioxide in the atmosphere is one of the main causes of global warming. Remote sensing technology has become an important means of monitoring the distribution of carbon dioxide gas. By remotely monitoring the temporal and spatial distributions of atmospheric carbon dioxide, people can further deepen their understanding of the global carbon process. The GOSAT (Greenhouse Gases Observing SATellite) CO2 L4B concentration data from 2010 to 2015 were validated using local station atmospheric data. The spatial and temporal distributions of the carbon dioxide concentration and its variation characteristics were analyzed. Based on the total primary productivity data and human emissions of carbon dioxide data, the influencing factors of spatial variations in carbon dioxide were analyzed. The results show that: (1) The correlation coefficient between GOSATL4B data and ground-measured data is above 0.95, which indicates that the remotely acquired data have high precision and stability. (2) The spatial distribution characteristics of carbon dioxide at different atmospheric pressure heights are quite different. The variation in the long-term series mean of carbon dioxide concentration levels at 17 vertical heights was studied. The fluctuations in concentration changes at different height levels vary, and the closer to the surface, the greater the fluctuation is. The near-surface carbon dioxide concentration (975 hPa) has the largest fluctuation. When the atmospheric pressure is low (for example, 150 or 100 hPa), the high carbon dioxide concentration region is banded and concentrated near the equator. The trends in carbon dioxide concentration over land and sea surfaces are similar, and the common pattern is that the concentration of carbon dioxide has been increasing. (3) The near-surface carbon dioxide concentration (975 hPa) has clearly different spatial characteristics. There are four high-value centers across the globe: East Asia, western Europe, the US East Coast, and Central Africa. The concentration of carbon dioxide in the Northern Hemisphere near the ground is higher than that in the Southern Hemisphere. The fluctuation in the Southern Hemisphere is relatively small, and the trend is opposite that in the Northern Hemisphere. (4) The concentration of carbon dioxide showed a significant growth trend during the study period. By studying the change characteristics of the monthly global average at the 975 hPa level (approximately 300 m above sea level) from January 2010 to October 2015, it can be seen that the global CO2 concentration has been above 400 ppm for most of the year, and it is increasing each year. (5) Compared with the Southern Hemisphere, the cyclical changes in carbon dioxide concentration in the Northern Hemisphere are obvious and large, while the trend in the Southern Hemisphere is relatively stable, and the change is small. There are opposite trends in the cyclical changes in the carbon dioxide concentration in the Northern and Southern Hemispheres. When the carbon concentration in the Northern Hemisphere resides over the annual high-value area, the Southern Hemisphere has a low-value area of carbon dioxide concentration every year. In addition, the change in carbon dioxide concentration during the year is obvious with seasonal changes. This should be related to changes in vegetation phenology and different seasons in the Northern and Southern Hemispheres. (6) Four countries in East Asia (Korea, Mongolia, Japan and China) from 2010 to 2014 were selected to analyze the relationship between GPP (gross primary production) and near-surface carbon dioxide concentration. These two factors have a significant inverse correlation. When carbon dioxide is at a minimum, the GPP is at its peak, and when carbon dioxide reaches its peak, the GPP reaches a minimum. The above relationship fully indicates that terrestrial ecosystems play an important role as carbon sink contributors in the carbon cycle. (7) The relationship between atmospheric carbon dioxide and carbon dioxide data from human activities from the Global Atmospheric Research Emissions Database was analyzed. The former is significantly and positively correlated with carbon dioxide emissions caused by human activities, indicating that human activities are an important factor in the increase in carbon dioxide.
- Research Article
4
- 10.5322/jesi.2014.23.6.1131
- Jun 30, 2014
- Journal of Environmental Science International
In this study, the variations of the carbon dioxide fluxes were investigated with soil temperatures in the grassplot and seasonal variations of carbon dioxide concentrations and fluxes were analysed. Soil temperatures, carbon dioxide concentrations and fluxes were measured on the grassplot in Pukyong National University. Field measurements were carried out 25 times from March in 2010 to March in 2011 with nine points on the grassplot. Seasonal variations of carbon dioxide concentrations and fluxes showed an inverse relation. In summer, carbon dioxide concentrations are lower and carbon dioxide fluxes are higher. In winter, carbon dioxide concentrations are higher and carbon dioxide fluxes are lower. On the grassplot, carbon dioxide emission rate increase when the soil temperature is more than <TEX>$20^{\circ}C$</TEX> and the emission rate decrease when the soil temperatures are less than <TEX>$10^{\circ}C$</TEX>. When the accumulated rainfall for five days before measurement day is 20~100 mm, it is showed that the more rainfall, the more carbon dioxide emissions. Carbon dioxide emission rate from the grassplot to the upper atmosphere was increased or decreased by the factors such as soil temperature, growth and wither of grass and rainfall. The results of this study showed that the emission of carbon dioxide in the grassplot is dominantly controlled by seasonal factors (especially soil temperature and rainfall).
- Research Article
115
- 10.1017/s0007485300051221
- Jun 1, 1991
- Bulletin of Entomological Research
Lactic acid, carbon dioxide and human sweat stimuli were presented singly and in combination to femaleAedes aegypti(Linnaeus) within a wind-tunnel system. The take-off, flight, landing and probing responses of the mosquitoes were recorded using direct observation and video techniques. The analyses determined the nature of the response to different stimuli and the concentration ranges within which specific behaviours occurred. A threshold carbon dioxide concentration for taking-off of approximately 0.03% above ambient was detected. Lactic acid and human sweat samples did not elicit take-off when presented alone, however, when they were combined with elevated carbon dioxide, take-off rate was enhanced in most of the combinations tested. Flight activity was positively correlated with carbon dioxide level and some evidence for synergism with lactic acid was found within a narrow window of blend concentrations. The factors eliciting landing were more subtle. There was a positive correlation between landing rate and carbon dioxide concentration. At the lowest carbon dioxide concentration tested, landing occurred only in the presence of lactic acid. Within a window of low to intermediate concentrations, landing rate was enhanced by this combination. At the highest carbon dioxide concentration, landing was however inhibited by the presence of lactic acid. The sweat extract elicited landings in the absence of elevated carbon dioxide. This indicated the presence of chemical stimuli, other than lactic acid, active in the short range. Probing occurred only at low carbon dioxide concentrations and there was no probing when lactic acid alone was tested. There was however probing in the presence of combined stimuli, the level of response seemed to be positively correlated with the ratio of carbon dioxide and lactic acid concentrations.
- Research Article
10
- 10.1002/j.1537-2197.1940.tb14706.x
- Jul 1, 1940
- American Journal of Botany
ASSIMILATION AND RESPIRATION OF EXCISED LEAVES AT HIGH CONCENTRATIONS OF CARBON DIOXIDE
- Research Article
5
- 10.1080/00387010.2014.909854
- Feb 3, 2015
- Spectroscopy Letters
In this work, Raman spectroscopic analysis was applied to determine the structures and cage occupancies of the hydrates that formed from the system of flue gas (simulated by carbon dioxide–nitrogen–sulfur dioxide)–sulfur dioxide aqueous solution, and from the system of flue gas–sulfur dioxide containing tetra-n-butyl ammonium bromide (TBAB) aqueous solutions (sulfur dioxide mass concentration 0, 1.0, and 7.0 wt%). Comprehensive TBAB (solid, aqueous, and hydrate) Raman spectra were also obtained. The results reveal that when TBAB is used as promoter, both sulfur dioxide and carbon dioxide are encaged in the hydrate from systems of flue gas-TBAB solution with low sulfur dioxide concentration (0, 1.0 wt%), whereas in the hydrate from the system of flue gas-sulfur dioxide highly concentrated (7.0 wt%) TBAB solution, sulfur dioxide will be the sole gas guest encaged in the semi-clathrate hydrate. This suggests the sulfur dioxide concentration significantly influences the hydrate cage occupancies and separation selectivity of the hydrate-based technology. A two-stage hydrate-based flue gas purification process is proposed: one aims at desulfurization when sulfur dioxide concentrates to a relatively high level with the solutions recycling and in the other we can remove the sulfur dioxide and carbon dioxide simultaneously.
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