scholarly journals The state of greenhouse gases in the atmosphere using global observations through 2018

2020 ◽  
Author(s):  
Oksana Tarasova ◽  
Alex Vermeulen ◽  
Jocelyn Turnbull ◽  
Yousuke Sawa ◽  
Ed Dlugokencky
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Radiative Forcing ◽  
Fossil Fuel ◽  
Global Analysis ◽  
Advisory Group ◽  
Average Growth Rate ◽  
Average Growth ◽  
The World

<p>We present results from the fifteenth annual Greenhouse Gas Bulletin (https://library.wmo.int/doc_num.php?explnum_id=10100) of the World Meteorological Organization (WMO). The results are based on research and observations performed by laboratories contributing to the WMO Global Atmosphere Watch (GAW) Programme (https://community.wmo.int/activity-areas/gaw).</p><p>The Bulletin presents results of global analyses of observational data collected according to GAW recommended practices and submitted to the World Data Center for Greenhouse Gases (WDCGG). Bulletins are prepared by the WMO/GAW Scientific Advisory Group for Greenhouse Gases in collaboration with WDCGG.</p><p>Observations used for the global analysis are collected at more than 100 marine and terrestrial sites worldwide for CO<sub>2</sub> and CH<sub>4</sub> and at a smaller number of sites for other greenhouse gases. The globally averaged surface mole fractions calculated from this in situ network reached new highs in 2018, with CO<sub>2</sub> at 407.8 ± 0.1 ppm, CH<sub>4</sub> at 1869 ± 2 ppb and N<sub>2</sub>O at 331.1 ± 0.1 ppb. These values constitute, respectively, 147%, 259% and 123% of pre-industrial (before 1750) levels. The increase in CO<sub>2</sub> from 2017 to 2018 is very close to that observed from 2016 to 2017 and practically equal to the average growth rate over the last decade. The increase of CH<sub>4</sub> from 2017 to 2018 was higher than both that observed from 2016 to 2017 and the average growth rate over the last decade. The increase of N<sub>2</sub>O from 2017 to 2018 was also higher than that observed from 2016 to 2017 and the average growth rate over the past 10 years. The National Oceanic and Atmospheric Administration (NOAA) Annual Greenhouse Gas Index (AGGI) shows that from 1990 to 2018, radiative forcing by long-lived greenhouse gases (GHGs) increased by 43%, with CO<sub>2</sub> accounting for about 81% of this increase.</p><p>The Bulletin highlights the value of the long-term measurement of the GHGs isotopic composition. In particular, it presents the use of the radiocarbon and <sup>13</sup>C measurements in atmospheric CO<sub>2</sub> in discriminating between fossil fuel combustion and natural sources of CO<sub>2</sub>. The simultaneous decline in both <sup>13</sup>C and <sup>14</sup>C content alongside CO<sub>2</sub> increases can only be explained by the ongoing release of CO<sub>2</sub> from fossil fuel burning. The Bulletin also articulates how the measurements of the stable isotopes can be used to provide the insights into the renewed growth of methane that started in 2007. Though there are several hypotheses articulated in the peer-reviewed literature, the most plausible is that an increase has occurred in some or all sources of biogenic (wetlands, ruminants or waste) emissions, which contain relatively little <sup>13</sup>C. An increase in the proportion of global emissions from microbial sources may have driven both the increase in the methane burden and the shift in δ<sup>13</sup>C-CH<sub>4</sub>.</p>

scholarly journals The state of greenhouse gases in the atmosphere using global observations through 2019

2021 ◽  
Author(s):  
Oksana Tarasova ◽  
Alex Vermeulen ◽  
Yousuke Sawa ◽  
Sander Houweling ◽  
Ed Dlugokencky
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Radiative Forcing ◽  
Global Analysis ◽  
Average Annual Growth Rate ◽  
Annual Growth ◽  
Annual Growth Rate ◽  
Emission Reductions ◽  
The World

<p>We present results from the sixteenth annual Greenhouse Gas Bulletin (https://library.wmo.int/doc_num.php?explnum_id=10437) of the World Meteorological Organization (WMO). The results are based on research and observations performed by laboratories contributing to the WMO Global Atmosphere Watch (GAW) Programme (https://community.wmo.int/activity-areas/gaw).</p><p>The Bulletin presents results of global analyses of observational data collected according to GAW recommended practices and submitted to the World Data Center for Greenhouse Gases (WDCGG). Bulletins are prepared by the WMO/GAW Scientific Advisory Group for Greenhouse Gases in collaboration with WDCGG.</p><p>Observations used for the global analysis are collected at more than 100 marine and terrestrial sites worldwide for CO<sub>2</sub> and CH<sub>4</sub> and at a smaller number of sites for other greenhouse gases. The globally averaged surface mole fractions calculated from this in situ network reached new highs in 2019, with CO<sub>2</sub> at 410.5 ± 0.2 ppm, CH<sub>4</sub> at 1877 ± 2 ppb, and N<sub>2</sub>O at 332.0 ± 0.1 ppb. These values constitute, respectively, 148%, 260% and 123% of pre-industrial (before 1750) levels. The increase in CO<sub>2</sub> from 2018 to 2019 (2.6 ppm) was larger than that observed from 2017 to 2018 and larger than the average annual growth rate over the last decade. For CH<sub>4</sub>, the increase from 2018 to 2019 (8 ppb) was slightly smaller than that observed from 2017 to 2018 but still greater than the average annual growth rate over the last decade. For N<sub>2</sub>O, the increase from 2018 to 2019 (0.9 ppb) was lower than that observed from 2017 to 2018 and practically equal to the average annual growth rate over the past 10 years. The National Oceanic and Atmospheric Administration (NOAA) Annual Greenhouse Gas Index (AGGI) shows that from 1990 to 2019, radiative forcing by long-lived greenhouse gases increased by 45%, with CO<sub>2</sub> accounting for about 80% of this increase.</p><p>The Bulletin highlights the potential impact of anthropogenic emission reductions due to COVID-19 lockdown measures on the levels of atmospheric concentrations of GHGs. These changes have been especially pronounced in urban areas and were visible in traditional pollutants as well as in greenhouse gases. However, the reduction in anthropogenic emissions due to confinement measures will not have a discernible effect on global mean atmospheric CO<sub>2</sub> in 2020 as this reduction will be smaller than, or at most, similar in size to the natural year-to-year variability of atmospheric CO<sub>2</sub>. Direct measurements of the CO<sub>2</sub> fluxes by ICOS directly demonstrated GHG emission reductions in a number of cities. </p><p>The Bulletin also describes the emission reduction opportunities related to methane. These opportunities are provided by emerging capabilities of methane observations from space and advances in transport modeling that allow for better source attribution and quantification. Globally averaged methane mole fraction has been increasing since 2007. Long-term observations and analysis of methane isotopic composition shed some light on this increase. The observed trend in δ<sup>13</sup>C-CH<sub>4</sub> is explained by a combined increase in microbial and fossil emissions. This trend points to the likely scenario that the methane increase is largely driven by the growing demand for energy and food.</p>

scholarly journals Detecting the influence of fossil fuel and bio-fuel black carbon aerosols on near surface temperature changes

2011 ◽  
Vol 11 (2) ◽  
pp. 799-816 ◽  
Author(s):  
G. S. Jones ◽  
N. Christidis ◽  
P. A. Stott
Keyword(s):  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Black Carbon ◽  
20Th Century ◽  
Radiative Forcing ◽  
Fossil Fuel ◽  
Climate Model ◽  
Global Climate ◽  
Anthropogenic Aerosols ◽  
Near Surface

Abstract. Past research has shown that the dominant influence on recent global climate changes is from anthropogenic greenhouse gas increases with implications for future increases in global temperatures. One mitigation proposal is to reduce black carbon aerosol emissions. How much warming can be offset by controlling black carbon is unclear, especially as its influence on past climate has not been previously unambiguously detected. In this study observations of near-surface warming over the last century are compared with simulations using a climate model, HadGEM1. In the simulations black carbon, from fossil fuel and bio-fuel sources (fBC), produces a positive radiative forcing of about +0.25 Wm−2 over the 20th century, compared with +2.52 Wm−2 for well mixed greenhouse gases. A simulated warming of global mean near-surface temperatures over the twentieth century from fBC of 0.14 ± 0.1 K compares with 1.06 ± 0.07 K from greenhouse gases, −0.58 ± 0.10 K from anthropogenic aerosols, ozone and land use changes and 0.09 ± 0.09 K from natural influences. Using a detection and attribution methodology, the observed warming since 1900 has detectable influences from anthropogenic and natural factors. Fossil fuel and bio-fuel black carbon is found to have a detectable contribution to the warming over the last 50 yr of the 20th century, although the results are sensitive to the period being examined as fBC is not detected for the later fifty year period ending in 2006. The attributed warming of fBC was found to be consistent with the warming from fBC unscaled by the detection analysis. This study suggests that there is a possible significant influence from fBC on global temperatures, but its influence is small compared to that from greenhouse gas emissions.

scholarly journals Analysis on Variation and Potential Source Regions of Greenhouse Gases Concentrations at Akedala Station, China

2021 ◽  
Author(s):  
Zhujun Zhao ◽  
Qing He ◽  
Quanwei Zhao ◽  
Hanlin Li ◽  
Zhongqi Lu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Greenhouse Gas Emission ◽  
Extreme Weather Events ◽  
Analysis Method ◽  
Average Growth ◽  
Backward Trajectories ◽  
Source Regions ◽  
Potential Source

Abstract The research on the variation of greenhouse gases concentrations in typical regions is one of the significant tasks to cope with climate change. Especially at present, the number of extreme weather events is gradually increasing and the trend of global warming is becoming increasingly obvious, the study on variation of greenhouse gases concentrations and their potential source regions can contribute to a scientific formulation of policies regarding greenhouse gas emission reduction as well as to the coordinated development of human and environment. Based on the data of greenhouse gases of Akedala Station from 2009 to 2019, this research studies characteristics of the time series and seasonal trends of greenhouse gases at this station and testes whether abrupt change exists by applying the linear trend analysis method, the contrastive and statistical analysis method and Mann-Kendall method. In addition, Pearson Correlation Coefficient is used to determine the correlation and homology among the four greenhouse gases and backward trajectories model is also used to explore the potential source regions of greenhouse gases at Akedala Station in different seasons. The greenhouse gases concentrations at Akedala Station show a trend of year-on-year growth, with CO2 concentrations ranging from 389.80×10− 6 to 408.79×10− 6 (molar fraction of substances, same below), CH4 concentrations ranging from1890.07×10− 9 to 1976.32×10− 9, N20 concentrations ranging from 321.26×10− 9 to 332.03×10− 9, and SF6 concentrations ranging from 7.04×10− 12 to 10.07×10− 12, the growth rate of which is similar to the decadal average growth rate in the northern hemisphere. There exist obvious seasonal variations, with CO2 concentrations showing high in winter and low in summer and CH4 showing a distinct “W”- shaped trend while N20 and SF6 showing little difference between the four seasons. A relatively strong correlation and homology exist among the four greenhouse gases except in summer, and the analysis based on backward trajectories model shows that the Akedala Station is influenced by the airflow from northwest or southwest throughout the year. Besides, the concentrations of greenhouse gas are closely related to source region of the emissions, biological and non-biological sources, monsoon, and atmospheric photochemical processes.

scholarly journals Detecting the influence of fossil fuel and bio-fuel black carbon aerosols on near surface temperature changes

2010 ◽  
Vol 10 (9) ◽  
pp. 20921-20974
Author(s):  
G. S. Jones ◽  
N. Christidis ◽  
P. A. Stott
Keyword(s):  
Greenhouse Gases ◽  
Greenhouse Gas ◽  
Black Carbon ◽  
20Th Century ◽  
Radiative Forcing ◽  
Fossil Fuel ◽  
Climate Model ◽  
Global Climate ◽  
Anthropogenic Aerosols ◽  
Near Surface

Abstract. Past research has shown that the dominant influence on recent global climate changes is from anthropogenic greenhouse gas increases with implications for future increases in global temperatures. One mitigation proposal is to reduce black carbon aerosol emissions. How much warming can be offset by the aerosol's control is unclear, especially as its influence on past climate has not been previously unambiguously detected. In this study observations of near-surface warming over the last century are compared with simulations using a climate model, HadGEM1. In the simulations black carbon, from fossil fuel and bio-fuel sources (fBC), produces a positive radiative forcing of about + 0.25 Wm−2 over the 20th century, compared with a little under + 2.5 Wm−2 for well mixed greenhouse gases. A simulated warming of global mean near-surface temperatures over the twentieth century from fBC of 0.14 ± 0.1 K compares with 1.06 ± 0.07 K from greenhouse gases, -0.58 ± 0.10 K from anthropogenic aerosols, ozone and land use changes and 0.09 ± 0.09 K from natural influences. Using a detection and attribution methodology, the observed warming since 1900 has detectable influences from anthropogenic and natural factors. Fossil fuel and bio-fuel black carbon is found to have a detectable contribution to the warming over the last 50 years of the 20th century, although the results are sensitive to a number of analysis choices, and fBC is not detected for the later fifty year period ending in 2006. The attributed warming of fBC was found to be consistent with the warming from the unscaled simulation. This study suggests that there is a possible significant influence from fBC on global temperatures, but its influence is small compared to that from greenhouse gas emissions.

scholarly journals Characteristics And Source Analysis of Greenhouse Gas Concentration Changes at Akedala Station in Central Asia

2021 ◽  
Author(s):  
Zhujun Zhao ◽  
LU Zhongqi ◽  
HE Qing ◽  
ZHAO Quanwei ◽  
WANG Jianlin
Keyword(s):  
Growth Rate ◽  
Greenhouse Gases ◽  
Central Asia ◽  
Greenhouse Gas ◽  
Source Analysis ◽  
Local Source ◽  
Long Distance ◽  
Average Growth ◽  
Gas Concentration ◽  
Concentration Changes

Abstract Mole fractions of atmospheric carbon dioxide (CO2), methane (CH4) ,nitrous oxide (N2O) and sulphur hexafluoride (SF6) have been continuously measured since September 2009 at the Akdala station (47˚06′N, 87˚58′E, 563.3 masl) in China. The station is located in the Central Asia and northwest of China, and it is the only station in that region with background conditions for long-term greenhouse gas observations. Characteristics of the mole fractions, growth rates as well as influence of long-distance transport were studied considering data from September 2009 to December 2019. The greenhouse gases concentrations at Akedala Station show a trend of year-on-year growth, with CO2 concentrations ranging from 389.80×10-6 to 408.79×10-6 (molar fraction of substances, same below), CH4 concentrations ranging from1890.07×10-9 to 1976.32×10-9, N2O concentrations ranging from 321.26×10-9 to 332.03×10-9, and SF6 concentrations ranging from 7.04×10-12 to 10.07×10-12, the growth rate of which is similar to the decadal average growth rate in the northern hemisphere. There exist obvious seasonal variations, with CO2 concentrations showing high in winter and low in summer and CH4 showing a distinct “W”- shaped trend while N2O and SF6 showing little difference between the four seasons. A relatively strong correlation and homology exist among the four greenhouse gases except in summer, and the analysis based on backward trajectories model shows that the Akedala Station is influenced by the airflow from northwest or southwest throughout the year. The Akedala station is an important atmospheric background station in Central Asia, and its greenhouse gas concentration levels and variation characteristics are significantly different from those of the background stations in the monsoon region. It’s degree changes are closely related to local source emissions, monsoon transport, and atmospheric photochemical processes.

Fuel Optimization for Power, Heat and CHP Systems Including Emissions Regulations and Ambient Conditions

2005 ◽  
Author(s):  
Manuel-Angel Gonzalez-Chapa ◽  
Jose-Ramon Vega-Galaz
Keyword(s):  
Power Systems ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Fossil Fuel ◽  
Good Practice ◽  
Combined Heat And Power ◽  
Ambient Conditions ◽  
Gas Emissions ◽  
The World ◽  
Fuel Optimization

Combined Heat and Power systems have been used all around the world due to their effective and viable way of transforming energy from fossil fuel. Indeed, the advantage of lower greenhouse gas emissions compared to those obtained in conventional power or conventional heat generation systems have been an important factor giving CHP systems an advantage over these conventional ones. Certainly CHP has been, and continues to be, a good practice while renewable technologies become more economically. While these technologies emerge it is important to continue minimizing these greenhouse gas emissions from conventional and CHP units as much as possible. This paper deals with the fuel optimization of power, heat and CHP systems including emissions and ambient conditions constraints. Ambient conditions variations are evaluated before solving the optimization and then introduced to the problem to consider their effects.

scholarly journals PERFORMANCE EVOLUTION OF JAMMU AND KASHMIR STATE FINANCIAL CORPORATION

2021 ◽  
Vol 9 (08) ◽  
pp. 647-650
Author(s):  
Maryama Gul ◽  
◽  
P.K. Sanse ◽  
Keyword(s):  
Growth Rate ◽  
Trend Analysis ◽  
Ratio Analysis ◽  
Average Growth Rate ◽  
Jammu And Kashmir ◽  
Average Growth ◽  
Research Period ◽  
Study Performance

The objective of this study was to assess the performance of JK SFC. The establishment of State financial Corporations was, one of the steps taken, at the official level to promote the growth of small and mediumscale industries. The Jammu and Kashmir State Financial Corporation is a statutory Corporation established under SFCs Act 1951(Central Act 63 of 1951) which is facing heavy losses due to no source of funds and no recovery of loans. In the present study performance of JKSFC was analyzed with different tools like trend analysis and ratio analysis and average growth rate. The results of the study show that performance of JKSFC is declining during the research period due tofacing problems of liquidity & solvency.

scholarly journals Cambodia: Subprime Degrees?

2013 ◽  
pp. 15-16 ◽  
Author(s):  
David Ford
Keyword(s):  
Higher Education ◽  
Growth Rate ◽  
Private Institutions ◽  
Average Growth Rate ◽  
Average Growth ◽  
Branch Campuses ◽  
The Past ◽  
New Institutions

The Cambodian economy has achieved a healthy average growth rate of about 7 percent, over the past decade. Higher education has expanded more than tenfold, in the same period, and now includes 91 institutions (68 universities and 23 institutes or schools) of which 59 percent are private institutions, and almost 200,000 students. Access has improved greatly, as many new institutions and branch campuses of existing institutions have opened in provincial centers.

Growth and carcass characteristics of crossbred lambs in various production systems

2012 ◽  
Vol 52 (5) ◽  
pp. 373 ◽  
Author(s):  
N. M. Fogarty ◽  
J. G. Mulholland
Keyword(s):  
Growth Rate ◽  
Production Systems ◽  
Growth Traits ◽  
Carcass Weight ◽  
Wagga Wagga ◽  
Hybrid Vigour ◽  
Average Growth Rate ◽  
Lower Growth ◽  
Average Growth ◽  
Lamb Growth

Lamb growth, carcass and pelt measurements are reported from 5775 lambs born to Border Leicester × Merino (BLM) and Hyfer (Dorset × Merino composite) ewes joined to Dorset, Suffolk and Hyfer rams in three lamb-production systems at Cowra and Wagga Wagga over 5 years. The production systems involved lambings at different seasons of the year and increasing levels of intensification from autumn annual joining, spring joining with a backup mating for non-pregnant ewes, to an accelerated 8-monthly lambing system. Lambs from BLM ewes were 0.7 kg heavier at birth and grew 3% faster and reached slaughter, at 18 kg carcass weight, 1–2 weeks earlier than did lambs from Hyfer ewes (P < 0.01). The advantage in growth rate of lambs from BLM compared with Hyfer ewes was greater for lambs born in November. These lambs had poorer growing conditions over the summer months, with 22% lower growth rate and taking 5 weeks longer to reach slaughter than did lambs born in March or August. There was no difference between Dorset and Suffolk sire breeds for any lamb growth traits, with lambs from Hyfer sires growing 7% slower. Ram and cryptorchid lambs reached slaughter 1 week earlier than did wethers, with ewes a further 9 days later (P < 0.01). Sex differences were maximised when lamb growth was greatest. There were no differences in carcass fat measurements between ram and cryptorchid lambs, although both were considerably leaner than wethers (2.2–3.0 mm fat at the GR site), which were 1.3–2.1 mm leaner than ewes at 18-kg carcass weight. The range in average growth rate of progeny of the BLM ewes from the 12 different source flocks at Cowra and Wagga Wagga was 10–14% of the mean which was twice the difference in average growth rate of progeny from the BLM and Hyfer dams. There was also significant variation among the BLM source flocks for carcass fat measurements. Lamb progeny from the different sire- and dam-breed combinations had varying levels of heterozygosity. There appears to be little loss of heterosis or hybrid vigour for lamb growth, although the sire breed × dam breed interaction was significant (P < 0.01) for age at slaughter at Wagga Wagga, in which the ranking of the lamb types was consistent with the levels of heterozygosity. The estimates of between-lambing repeatability for the ewes were highest for birthweight (0.35 Cowra and 0.27 Wagga Wagga) and declined at later ages (0.26–0.17), with lower estimates for carcass traits.

Performance of young breeding cattle in commercial herds in the south-west of Western Australia. 3. Calf growth, dystocia, and their relationship with production and fertility measurements in first-calf heifers

1991 ◽  
Vol 31 (4) ◽  
pp. 455 ◽  
Author(s):  
GJ Sawyer ◽  
DJ Barker ◽  
RJ Morris
Keyword(s):  
Growth Rate ◽  
Birth Weight ◽  
Western Australia ◽  
The South ◽  
Average Growth Rate ◽  
Average Growth ◽  
Calf Growth ◽  
South West ◽  
Condition Score ◽  
Recorded Data

The preweaning growth of the progeny from 2531 first-calf heifers calving on commercial properties in the south-west of Western Australia was studied over 5 years. Animals included the progeny of Angus sires mated to Angus, Angus x Friesian, Simford, Hereford and Beef Shorthorn crossbred heifers; the progeny of Hereford sires mated to Hereford, Hereford x Friesian, and Beef Shorthorn crossbred; and those of Devon crossbred, Simford or Wokalup multibreed heifers mated inter se. Calves were born between mid January and July of each year and date of birth, calving information and calf growth through to weaning at an average age of 230 days were recorded. Data recorded on the calves' dams included regular liveweight and condition score assessment and the date of second calving. Angus-sired calves were lighter at birth than Hereford-sired calves; breed means ranged from 25.1 kg for purebred Angus to 33.2 kg for Wokalup multibreeds, with male calves weighing 1.4 kg more than females at birth. Calf birth weight was positively and linearly related to weight of dam at the beginning of joining. Breed of calf, sex of calf, year of birth, day of the year born, liveweight and liveweight change of the dam at the beginning of rejoining all significantly influenced calf growth, with up to 64% of variation accounted for. At 50 days of age, Devon crossbreds, Simfords and Wokalup multibreeds were significantly heavier than crossbred Hereford or Angus calves, and this trend persisted until weaning. The average growth rate to 200 days of Angus calves was 0.113 kg/day slower, and Hereford calves 0.77 kg/day slower, than the average growth rate of their respective crossbred calves. Heaviest 200-day weights were found in Devon crossbred (235 kg), Simford (221 kg) and Wokalup multibreed (219 kg) calves. A strong seasonal influence on calf growth was detected. Each 1 day increase in calf age in calves born between mid January and June resulted in 0.29 kg extra liveweight at 100 days and 0.68 kg extra liveweight at 200 days of age. Overall, the liveweight of the dam at the beginning of re-joining was positively associated with calf growth, with 0.119 kg of calf liveweight/kg dam liveweight at 100 days and 0.123 kg at 200 days. There was less effect of dam liveweight in Herefords and Hereford x Friesians on calf growth to 200 days, but this relationship was closer in faster growing and later maturing breeds, including Angus x Friesian, Simford, and Wokalup multibreed. The dairy crossbreeds generally lost weight at the beginning of re-joining, resulting in a negative association between this weight change and calf growth to 100 days. No assistance was required in 93% of calvings and the highest incidence of dystocia corresponded with the highest birth weight calves in Wokalup multibreeds. The most common calving difficulty was an apparently slow birth where no assistance was given, resulting in a stillborn calf. Male calves experienced 3 times the level of dystocia recorded for female calves. There was no association detected between dystocia and dam liveweight subsequent to calving. The study highlighted the importance of dam breed, liveweight and condition of the dam and timing of calving as important influences on the growth of progeny reared by first-calf heifers.

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