scholarly journals Estimating regional scale methane flux and budgets using CARVE aircraft measurements over Alaska

2017 ◽  
Author(s):  
Sean Hartery ◽  
Róisín Commane ◽  
Jakob Lindaas ◽  
Colm Sweeney ◽  
John Henderson ◽  
...  
Keyword(s):  
Soil Temperature ◽  
Transport Model ◽  
Linear Regression Analysis ◽  
Regional Scale ◽  
Region Of Interest ◽  
Methane Flux ◽  
Multiple Linear Regression Analysis ◽  
Total Surface Area ◽  
Study Region ◽  
Soil Temperature And Moisture

Abstract. Methane (CH4) is the second most important greenhouse gas but its emissions from northern regions is still poorly constrained. In this study, we analyze a subset of in situ CH4 aircraft observations made over Alaska during the growing seasons of 2012–2014 as part of the Carbon in Arctic Reservoir Vulnerability Experiment (CARVE). Surface CH4 fluxes are estimated using an atmospheric particle transport model which quantitatively links surface emissions from Alaska and the western Yukon with observations of enhanced CH4 in the boundary layer. We estimate that between May and September, 2.1 ± 0.5 Tg, 1.7 ± 0.4 Tg and 2.0 ± 0.3 Tg of CH4 were emitted from the region of interest for 2012–2014, respectively. The predominant sources of the CH4 budget were two broadly classed eco-regions within our domain, with CH4 from the tundra region accounting for over half of the overall budget, despite only representing 18 % of the total surface area. Boreal regions, which cover a large part of the study region, accounted for the remainder of the emissions. Simple multiple linear regression analysis revealed that overall, CH4 flux were largely driven by soil temperature and elevation. In regions specifically dominated by wetlands, soil temperature and moisture at 10 cm depth were important explanatory variables while in regions that were not wetlands, soil temperature and moisture at 40 cm depth were more important, reflecting the depth at which methanogenesis occurs. Although similar variables have been found in the past to control CH4 emissions at local scales, this study shows that they can be used to generate a statistical model to estimate the regional scale CH4 budget.

scholarly journals Estimating regional-scale methane flux and budgets using CARVE aircraft measurements over Alaska

2018 ◽  
Vol 18 (1) ◽  
pp. 185-202 ◽  
Author(s):  
Sean Hartery ◽  
Róisín Commane ◽  
Jakob Lindaas ◽  
Colm Sweeney ◽  
John Henderson ◽  
...  
Keyword(s):  
Soil Temperature ◽  
Dispersion Model ◽  
Linear Regression Analysis ◽  
Regional Scale ◽  
Methane Flux ◽  
Particle Dispersion ◽  
Environmental Drivers ◽  
Study Region ◽  
Ch4 Emissions ◽  
Soil Temperature And Moisture

Abstract. Methane (CH4) is the second most important greenhouse gas but its emissions from northern regions are still poorly constrained. In this study, we analyze a subset of in situ CH4 aircraft observations made over Alaska during the growing seasons of 2012–2014 as part of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE). Net surface CH4 fluxes are estimated using a Lagrangian particle dispersion model which quantitatively links surface emissions from Alaska and the western Yukon with observations of enhanced CH4 in the mixed layer. We estimate that between May and September, net CH4 emissions from the region of interest were 2.2 ± 0.5 Tg, 1.9 ± 0.4 Tg, and 2.3 ± 0.6 Tg of CH4 for 2012, 2013, and 2014, respectively. If emissions are only attributed to two biogenic eco-regions within our domain, then tundra regions were the predominant source, accounting for over half of the overall budget despite only representing 18 % of the total surface area. Boreal regions, which cover a large part of the study region, accounted for the remainder of the emissions. Simple multiple linear regression analysis revealed that, overall, CH4 fluxes were largely driven by soil temperature and elevation. In regions specifically dominated by wetlands, soil temperature and moisture at 10 cm depth were important explanatory variables while in regions that were not wetlands, soil temperature and moisture at 40 cm depth were more important, suggesting deeper methanogenesis in drier soils. Although similar environmental drivers have been found in the past to control CH4 emissions at local scales, this study shows that they can be used to generate a statistical model to estimate the regional-scale net CH4 budget.

scholarly journals Near-ground ozone source attributions and outflow in central eastern China during MTX2006

2008 ◽  
Vol 8 (24) ◽  
pp. 7335-7351 ◽  
Author(s):  
J. Li ◽  
Z. Wang ◽  
H. Akimoto ◽  
K. Yamaji ◽  
M. Takigawa ◽  
...  
Keyword(s):  
Transport Model ◽  
Eastern China ◽  
Regional Scale ◽  
Horizontal Distribution ◽  
Photochemical Reactions ◽  
Ozone Production ◽  
Chemical Transport Model ◽  
Ozone Level ◽  
Study Region ◽  
Central Eastern

Abstract. A 3-D regional chemical transport model, the Nested Air Quality Prediction Model System (NAQPMS), with an on-line tracer tagging module was used to study the source of the near-ground (<1.5 km above ground level) ozone at Mt. Tai (36.25° N, 117.10° E, 1534 m a.s.l.) in Central Eastern China (CEC) during the Mount Tai eXperiment 2006 (MTX2006). The model reproduced the temporal and spatial variations of near-ground ozone and other pollutants, and it captured highly polluted and clean cases well. The simulated near-ground ozone level over CEC was 60–85 ppbv (parts per billion by volume), which was higher than values in Japan and over the North Pacific (20–50 ppbv). The simulated tagged tracer data indicated that the regional-scale transport of chemically produced ozone over other areas in CEC contributed to the greatest fraction (49%) of the near-ground mean ozone at Mt. Tai in June; in situ photochemistry contributed only 12%. Due to high anthropogenic and biomass burning emissions that occurred in the southern part of the CEC, the contribution to ground ozone levels from this area played the most important role (32.4 ppbv, 37.9% of total ozone) in the monthly mean ozone concentration at Mt. Tai; values reached 59 ppbv (62%) on 6–7 June 2006. The monthly mean horizontal distribution of chemically produced ozone from various ozone production regions indicated that photochemical reactions controlled the spatial distribution of O3 over CEC. The regional-scale transport of pollutants also played an important role in the spatial and temporal distribution of ozone over CEC. Chemically produced ozone from the southern part of the study region can be transported northeastwardly to the northern rim of CEC; the mean contribution was 5–10 ppbv, and it reached 25 ppbv during high ozone events. Studies of the outflow of CEC ozone and its precursors, as well as their influences and contributions to the ozone level over adjacent regions/countries, revealed that the contribution of CEC ozone to mean ozone mixing ratios over the Korean Peninsula and Japan was 5–15 ppbv, of which about half was due to the direct transport of ozone from CEC and half was produced locally by ozone precursors transported from CEC.

scholarly journals The Short-Term Impact of Different Silvicultural Thinnings on Soil Nematode and Microarthropod Biodiversity in Artificial Black Pine Stands

Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1212
Author(s):  
Silvia Landi ◽  
Giada d’Errico ◽  
Francesco Binazzi ◽  
Umberto Di Salvatore ◽  
Lorenzo Gardin ◽  
...  
Keyword(s):  
Soil Temperature ◽  
Regional Scale ◽  
Central Italy ◽  
Nematode Community ◽  
Soil Nematode ◽  
Short Term ◽  
Short Term Experiment ◽  
The Impact ◽  
Soil Indicators ◽  
Soil Temperature And Moisture

Soil invertebrates represent almost a quarter of the total diversity of living organisms and their activity affects the entire soil ecological process. The choice of adequate thinning systems may differently affect soil nematode and microarthropod biodiversity in artificial black pinewoods. In this work, the results of the impact of different thinnings on the structure of nematode and microarthropod communities was reported. In a short-term experiment, thinning from below and selective thinning were compared to unmanaged stands to provide indications at the regional scale in central Italy. Soil nematode and microarthropod biodiversity was explored by examining community structure, assessing biodiversity. The interaction between environmental variables (crown volume, Photosynthetically Active Radiation, soil texture, soil temperature, and moisture) with taxa abundance of nematodes and microarthropods were also reported. The results indicated that the effects of thinning practices were temporary and varied between years. Soil nematode community shifted during the first and third years of thinning managements only in the Pratomagno site, while soil microarthropod community shifted in both sites only in the second year. The total nematode abundance was minimally affected by thinning practices, while the nematode community composition showed a decrease of omnivores and predators in the first years. Soil indicators showed inconsistent results. In microarthropods, mites and collembola were the least affected by thinning in terms of abundance and species biodiversity, while eu-edaphic taxa of Chilopoda, Diplopoda, and Pauropoda were not influenced by thinning, hemi-edaphic and epi-edaphic taxa of Coleoptera, Diptera, Hymenoptera, Tysanoptera, and Hemiptera were negatively affected. Soil indicators such as Shannon-Weiner and Simpson indices and soil biological quality (QBS-ar) improved in thinning from below in both sites. Soil temperature and moisture were the main driving factors in affecting soil nematode and microarthropods communities. Thinning from below probably allowed a more rapid recovery than selective thinning.

scholarly journals Regional-scale modeling of near-ground ozone in the Central East China, source attributions and an assessment of outflow to East Asia – The role of regional-scale transport during MTX2006

2008 ◽  
Vol 8 (4) ◽  
pp. 13159-13195 ◽  
Author(s):  
J. Li ◽  
Z. Wang ◽  
H. Akimoto ◽  
K. Yamaji ◽  
M. Takigawa ◽  
...  
Keyword(s):  
Transport Model ◽  
Regional Scale ◽  
Temporal Distribution ◽  
Ground Level ◽  
Horizontal Distribution ◽  
Photochemical Reactions ◽  
East China ◽  
Chemical Transport Model ◽  
Ozone Level ◽  
Study Region

Abstract. A 3-D regional chemical transport model, the Nested Air Quality Prediction Model System (NAQPMS), with an on-line tracer tagging module was applied to study the source of the near-ground (<1.5 km above ground level) ozone at Mt. Tai (36.25°N, 117.10°E, 1534 m a.s.l.) in Central East China (CEC) during the Mount Tai eXperiment 2006 (MTX2006): regional ozone photochemistry and aerosol studies in Central East China in June, 2006. The model reproduced the temporal and spatial variations of near-ground ozone and other pollutants. In particular, the model captured highly polluted and clean cases well. The simulated near-ground ozone over CEC is 60–85 ppbv (parts per billion by volume), higher than those (20–50 ppbv) in Japan and over the North Pacific. The simulated tagged tracer indicates that the regional-scale transport of chemically produced ozone over other areas in CEC contributes to the most fractions (49%) of the near-ground mean ozone at Mt. Tai in June, rather than the in-situ photochemistry (12%). Due to high anthropogenic and biomass burning emissions, the contributions of the ground ozone from the southern part of CEC plays the most important role (32.4 ppbv, 37.9% of total ozone) in the monthly mean ozone concentration at Mt. Tai, which even reached 59 ppbv (62%) on 6–7 June 2006. The monthly mean horizontal distribution of chemically produced ozone from various source regions indicates that the spatial distribution of O3 over CEC is controlled by the photochemical reactions. In addition, the regional-scale transport of pollutants also plays an important role in the spatial and temporal distribution of ozone over CEC. The chemically produced ozone from the southern part of the study region can be transported northeastwardly to the northern rim of CEC. The mean contribution is 5–10 ppbv, and it can reach 25 ppbv during high ozone events. This work also studied the outflow of CEC ozone and its precursors, as well as their influences and contributions to the ozone level over adjacent regions/countries. It shows that the contribution of CEC ozone to mean ozone mixing ratios over Korea Peninsula and Japan is 5–15 ppbv, of which about half was due to the direct transport of ozone from CEC and half was contributed by the ozone produced locally by the transported ozone precursors from CEC.

scholarly journals Effect of Evolocumab on Vulnerable Coronary Plaques: A Serial Coronary Computed Tomography Angiography Study

2020 ◽  
Vol 9 (10) ◽  
pp. 3338
Author(s):  
Keiji Hirai ◽  
Shigeki Imamura ◽  
Aizan Hirai ◽  
Susumu Ookawara ◽  
Yoshiyuki Morishita
Keyword(s):  
Computed Tomography ◽  
Linear Regression Analysis ◽  
Region Of Interest ◽  
Multiple Linear Regression Analysis ◽  
Coronary Computed Tomography ◽  
Standard Coefficient ◽  
Remodeling Index ◽  
Artery Disease ◽  
Ct Density ◽  
Coronary Artery Disease Progression

This study investigated the effects of evolocumab on vulnerable coronary plaques and factors associated with the change in stability and size of plaques in patients taking statins. Vulnerable coronary plaques were defined using coronary computed tomography (CT) angiography as having a density of <50 HU within the region of interest and a remodeling index ≥1.1. The changes in minimum CT density, remodeling index, and percent stenosis of vulnerable coronary plaques after six months of evolocumab administration were retrospectively analyzed in 136 vulnerable coronary plaques from 98 patients (68 men and 30 women; mean age: 72.9 ± 8.7 years) treated with a statin. The administration of evolocumab significantly increased the minimum CT density (39.1 ± 8.1 HU to 84.9 ± 31.4 HU, p < 0.001), reduced the remodeling index (1.29 ± 0.11 to 1.19 ± 0.10, p < 0.001), and decreased the percent stenosis (27.0 ± 10.4% to 21.2 ± 9.8%, p < 0.001). Multiple linear regression analysis revealed that baseline percent stenosis (standard coefficient (β) = −0.391, p = 0.002) independently correlated with the change in minimum CT density, whereas the baseline remodeling index (β = −0.368, p < 0.001) independently correlated with a change in the remodeling index. Evolocumab stabilized vulnerable coronary plaques and reduced their size. These results suggest that evolocumab protects against coronary artery disease progression in patients taking statins.

Pengaruh Motivasi Kerja Dan Lingkungan Kerja Terhadap Kinerja Karyawan Bappeda Kabupaten Wonosobo Tahun 2013

2017 ◽  
Vol 1 (2) ◽  
pp. 135-147
Author(s):  
Ary Sutrischastini ◽  
Ratna Setyani
Keyword(s):  
Work Environment ◽  
Work Motivation ◽  
Employee Performance ◽  
Linear Regression Analysis ◽  
Test Validity ◽  
Multiple Linear Regression Analysis ◽  
Reliability Testing ◽  
Evaluation Influence ◽  
Environment Variables ◽  
Research Goal

This research goal is to identification and evaluation influence of work motivation and work environment to employee’s performance in BAPPEDA Kabupaten Wonosobo. The object of this research is 37 employees of Badan Perencanaan Pembangunan Kabupaten Wonosobo. And the location of this research is at Badan Perencanaan Pembangunan Kabupaten Wonosobo. The analysis used is test validity, reliability testing, and test the hypothesis, with the help of the computer program SPSS version 17, using multiple linear regression analysis. Based on calculations of data and analysis used, the regression equation is obtained: Y = 11.733 + 0.320 X1 +0.334 X2 + ε, by using the equation regression analytical method can conclude that (X1) take effect positively against employees performance. With t value in amount of 2,219 (bigger than t in table in amount of 1,690) and significance value in amount of 0,33. By applying significance limited value in amount of 0,05, it means, hypothesis that claim if work motivation take effect against employees performance can be accepted. There is a positive and significant correlation between work environment variables (X2) against employees. With t value in amount of 2,219 (bigger than t in table in amount of 1,690) and significance value in amount of 0,33 (smaller than 0,5). Simultaneously, work motivation take effect positively and significantly against employees performance with the F value in amount of 11,562 (bigger than 0.05), then obtained significance value 0.000. It can be concluded that the work motivation and work environment has a positive and significant influence on employee performance in BAPPEDA Kabupaten Wonosobo.

PENGARUH FAKTOR-FAKTOR INTERNAL PERBANKAN TERHADAP NON PERFORMING FINANCING PADA BANK UMUM SYARIAH

2019 ◽  
Vol 6 (2) ◽  
pp. 115-130
Author(s):  
Eka Ambara Harci Putranta ◽  
Lilik Ambarwati
Keyword(s):  
Linear Regression ◽  
Multiple Linear Regression ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Capital Adequacy ◽  
Annual Reports ◽  
Regression Methods ◽  
Capital Adequacy Ratio ◽  
Negative Effect ◽  
Independent Variable

The study aims to analyze the influence of internal banking factors in the form of: Capital Adequency Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing at Sharia Banks. This research method used multiple linear regression analysis with the help of SPSS 16.00 software which is used to see the influence between the independent variables in the form of Capital Adequacy Ratio (CAR), Financing to Deposit Ratio (FDR) and Total Assets (TA) to Non Performing Financing. The sample of this study was 3 Islamic Commercial Banks, so there were 36 annual reports obtained through purposive sampling, then analyzed using multiple linear regression methods. The results showed that based on the F Test, the independent variable had an effect on the NPF, indicated by the F value of 17,016 and significance of 0,000, overall the independent variable was able to explain the effect of 69.60%. While based on the partial t test, showed that CAR has a significant negative effect, Total assets have a significant positive effect with a significance value below 0.05 (5%). Meanwhile FDR does not affect NPF.

PENGARUH TRANSPARANSI PENGELOLAAN KEUANGAN DANA DESA DAN PEMBERDAYAAN MASYARAKAT TERHADAP KESEJAHTERAAN MASYARAKAT DESA SIDOHARJO

2020 ◽  
Vol 28 (1) ◽  
pp. 35-50
Author(s):  
Dewi Kusuma Wardani ◽  
Ratih Ranika Putri Utami
Keyword(s):  
Financial Management ◽  
Linear Regression Analysis ◽  
Sampling Technique ◽  
Multiple Linear Regression Analysis ◽  
Community Empowerment ◽  
Primary Data ◽  
Community Members ◽  
The People ◽  
Quantitative Descriptive ◽  
Positive Effect

This study aims to determine the effect of transparency in financial management of village funds and community empowerment on community welfare in Sidoharjo Village, Tepus District, Gunungkidul Regency. This research method uses quantitative descriptive methods and primary data using questionnaires. This study took a sample of residents who were divided into 11 hamlets in Sidoharjo Village, Tepus District, Gunung kidul Regency. The sampling technique is stratified random sampling. Data collection is done by distributing questionnaires directly to people’s homes, attending social gatherings and routine meetings held by community members. It aims to obtain more data from respondents directly. The number of questionnaires processed was 120 questionnaires. Data were analyzed using multiple linear regression analysis. The results of this study indicate that community empowerment has a positive effect on the welfare of the people of Sidoharjo Village, Tepus District, Gunungkidul Regency, while transparency in financial management of village funds does not affect the welfare of the community in Sidoharjo Village, Tepus District, Gunungkidul Regency.

Pengaruh Tekanan Waktu, Locus Of Control , Tindakan Supervisi, Dan Materialitas Terhadap Penghentian Prematur Atas Prosedur Audit Studi Kasus Pada Kantor Akuntan Publik Daerah Istimewa Yogyakarta Tahun 2015

2017 ◽  
Vol 24 (1) ◽  
pp. 35-53
Author(s):  
Sulastiningsih Sulastiningsih ◽  
Intan Ayu Candra
Keyword(s):  
Locus Of Control ◽  
Premature Termination ◽  
Sampling Methods ◽  
Time Pressure ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Test Reliability ◽  
Friedman Test ◽  
Independent Variables ◽  
Public Accountant

The purpose of this study is to prove: (1) Time pressure, locus of control, the action of supervision and materiality partially affect the premature termination of the audit procedures (2) Time pressure, locus of control, supervision and materiality simultaneously affect the premature termination on the audit procedures. This research was conducted in Public Accountant firm in Yogyakarta region of which total 12 samples of KAP, by distributing 105 questionnaires, and 57 questionnaires were returned (54%). 34 of the returned questionnaires can be processed (34%). The samples in this study were determined by using non-probability sampling, one of purposive sampling methods. Data analysis consisted of: (1) validity test, reliability test and classical assumption. The result showed that the instruments used are quite reliable and valid (2) multiple linear regression analysis. The results are (a) Some of independent variables partially affect premature termination of the audit procedure, while the action of supervision does not influence premature termination of audit procedures (b) All independent variables influence simultaneously to the premature termination of the audit procedures (c) All independent variables showed that as much as 55% it affects on premature termination of the audit procedures, the rest of it are influenced by other variables. (3) Friedman Test. The result shows that there are order of priority of audit procedures being terminated.

Pengaruh Tingkat Literasi Keuangan Syariah dan Kepercayaan Masyarakat terhadap Minat Menabung di Bank Syariah

2020 ◽  
Vol 3 (2) ◽  
pp. 140-153
Author(s):  
Resti Fadhilah Nurrohmah ◽  
Radia Purbayati
Keyword(s):  
Financial Literacy ◽  
Linear Regression Analysis ◽  
Public Trust ◽  
Multiple Linear Regression Analysis ◽  
Primary Data ◽  
Public Confidence ◽  
Islamic Banks ◽  
Variable Level ◽  
Analysis Technique ◽  
The City

The purpose of this study was to study the level of Islamic financial literacy and public confidence in the interest in saving in Islamic banks. The variables in this study are the level of Islamic financial literacy (X1), public trust (X2), and interest in saving (Y).The method of this study is descriptive quantitative approach. The data source of this study are primary data obtained by distributing questionnaires. Respondents taken are residents in the city of Bandung, with samples domiciled in the city of Bandung and at least 17 years old. The data analysis technique uses multiple linear regression analysis. The results showed that the variable level of islamic financial literacy and public trust has positive effect in the interest in saving in Islamic banks. The findings in this study provide a reference to Islamic banks, the level of literacy and public trust regarding interest in saving, therefore Islamic banks must socialize to the public.

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