scholarly journals Changing trends and emissions of hydrochlorofluorocarbons and their hydrofluorocarbon replacements

2016 ◽  
Author(s):  
Peter G. Simmonds ◽  
Matthew Rigby ◽  
Archibold McCulloch ◽  
Simon O'Doherty ◽  
Dickon Young ◽  
...  
Keyword(s):  
Growth Rates ◽  
Montreal Protocol ◽  
Hfc 134A ◽  
Production And Consumption ◽  
Ozone Depleting Substances ◽  
Phase Out ◽  
Article 5 ◽  
The Impact ◽  
Global Emissions

Abstract. High frequency, in situ global observations of HCFC-22 (CHClF2), HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2) and HCFC-124 (CHClFCF3) and their main HFC replacements HFC-134a (CH2FCF3), HFC-125 (CHF2CF3), HFC-143a (CH3CF3), and HFC-32 (CH2F2) have been used to determine their changing global growth rates and emissions in response to the Montreal Protocol and its recent amendments. The 2007 adjustment to the Montreal Protocol required the accelerated phase-out of HCFCs with global production and consumption capped in 2013, to mitigate their environmental impact as both ozone depleting substances and important greenhouse gases. We find that this change has coincided with a reduction in global emissions of the four HCFCs with aggregated global emissions in 2015 of 444 ± 75 Gg/yr, in CO2 equivalent units (CO2 e) 0.75 ± 0.1 Gt/yr, compared with 483 ± 70 Gg/yr (0.82 ± 0.1 Gt/yr CO2 e) in 2010. (All quoted uncertainties in this paper are 1 sigma). About 80 % of the total HCFC atmospheric burden in 2015 is HCFC-22, where global HCFC emissions appear to have been relatively constant in spite of the 2013 cap on global production and consumption. We attribute this to a probable increase in production and consumption of HCFC-22 in Montreal Protocol Article 5 (developing) countries and the continuing release of HCFC-22 from the large banks which dominate HCFC global emissions. Conversely, the four HFCs all show increasing annual growth rates with aggregated global HFCs emissions in 2015 of 329 ± 70 Gg/yr (0.65 ± 0.12 Gt/yr CO2 e) compared to 2010 with 240 ± 50 Gg/yr (0.47 ± 0.08 Gt/yr CO2 e). As HCFCs are replaced by HFCs we investigate the impact of the shift to refrigerant blends which have lower global warming potentials (GWPs). We also note that emissions of HFC-125 and HFC-32 appear to have increased more rapidly during the 2011–2015 5-yr period compared to 2006–2010.

scholarly journals Changing trends and emissions of hydrochlorofluorocarbons (HCFCs) and their hydrofluorocarbon (HFCs) replacements

2017 ◽  
Vol 17 (7) ◽  
pp. 4641-4655 ◽  
Author(s):  
Peter G. Simmonds ◽  
Matthew Rigby ◽  
Archie McCulloch ◽  
Simon O'Doherty ◽  
Dickon Young ◽  
...  
Keyword(s):  
Mole Fraction ◽  
Growth Rates ◽  
Montreal Protocol ◽  
Hfc 134A ◽  
Production And Consumption ◽  
Ozone Depleting Substances ◽  
Phase Out ◽  
Article 5 ◽  
Global Emissions ◽  
Global Mean

Abstract. High-frequency, in situ global observations of HCFC-22 (CHClF2), HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2) and HCFC-124 (CHClFCF3) and their main HFC replacements, HFC-134a (CH2FCF3), HFC-125 (CHF2CF3), HFC-143a (CH3CF3) and HFC-32 (CH2F2), have been used to determine their changing global growth rates and emissions in response to the Montreal Protocol and its recent amendments. Global mean mole fractions of HCFC-22, -141b, and -142b have increased throughout the observation period, reaching 234, 24.3 and 22.4 pmol mol−1, respectively, in 2015. HCFC-124 reached a maximum global mean mole fraction of 1.48 pmol mol−1 in 2007 and has since declined by 23 % to 1.14 pmol mol−1 in 2015. The HFCs all show increasing global mean mole fractions. In 2015 the global mean mole fractions (pmol mol−1) were 83.3 (HFC-134a), 18.4 (HFC-125), 17.7 (HFC-143a) and 10.5 (HFC-32). The 2007 adjustment to the Montreal Protocol required the accelerated phase-out of emissive uses of HCFCs with global production and consumption capped in 2013 to mitigate their environmental impact as both ozone-depleting substances and important greenhouse gases. We find that this change has coincided with a stabilisation, or moderate reduction, in global emissions of the four HCFCs with aggregated global emissions in 2015 of 449 ± 75 Gg yr−1, in CO2 equivalent units (CO2 eq.) 0.76 ± 0.1 Gt yr−1, compared with 483 ± 70 Gg yr−1 (0.82 ± 0.1 Gt yr−1 CO2 eq.) in 2010 (uncertainties are 1σ throughout this paper). About 79 % of the total HCFC atmospheric burden in 2015 is HCFC-22, where global emissions appear to have been relatively similar since 2011, in spite of the 2013 cap on emissive uses. We attribute this to a probable increase in production and consumption of HCFC-22 in Montreal Protocol Article 5 (developing) countries and the continuing release of HCFC-22 from the large banks which dominate HCFC global emissions. Conversely, the four HFCs all show increasing mole fraction growth rates with aggregated global HFC emissions of 327 ± 70 Gg yr−1 (0.65 ± 0.12 Gt yr−1 CO2 eq.) in 2015 compared to 240 ± 50 Gg yr−1 (0.47 ± 0.08 Gt yr−1 CO2 eq.) in 2010. We also note that emissions of HFC-125 and HFC-32 appear to have increased more rapidly averaged over the 5-year period 2011–2015, compared to 2006–2010. As noted by Lunt et al. (2015) this may reflect a change to refrigerant blends, such as R-410A, which contain HFC-32 and -125 as a 50 : 50 blend.

scholarly journals Toward resolving the mysterious budget discrepancy of ozone-depleting CCl<sub>4</sub>: An analysis of top-down emissions from China

2018 ◽  
Author(s):  
Sunyoung Park ◽  
Shanlan Li ◽  
Jens Mühle ◽  
Simon O'Doherty ◽  
Ray F. Weiss ◽  
...  
Keyword(s):  
First Generation ◽  
Montreal Protocol ◽  
Monitoring Site ◽  
Top Down ◽  
Chemical Manufacturing ◽  
Production And Consumption ◽  
Better Regulation ◽  
Regulation Strategies ◽  
Ozone Depleting Substances ◽  
Phase Out

Abstract. Emissive production and use of carbon tetrachloride (CCl4), one of the first-generation ozone-depleting substances, have been banned by the Montreal Protocol with the 2010 phase-out for developing countries, but production and consumption for non-dispersive use as a chemical feedstock and as process agent are still allowed. Here, we present evidence that significant unreported emissions of CCl4 still persist, based on the high frequency and magnitude of CCl4 pollution events observed in the 8-year real time atmospheric measurement record at Gosan station, a regional background monitoring site in East Asia. From this we estimate top-down emissions of CCl4 amounting to 23.6 ± 7.1 Gg yr−1 from 2011 to 2015 for China, in contrast to the 4.3–5.2 Gg yr−1 reported as the most up-to-date post-2010 Chinese bottom-up emissions. The missing emissions (~ 19 Gg yr−1) for China are highly significant, contributing about 54 % of global CCl4 emissions. We show that 89 ± 6 % of the CCl4 enhancements observed at Gosan can be accounted for by fugitive emissions of CCl4 occurring at the factory level during the production of CH3Cl, CH2Cl2, CHCl3 and C2Cl4 (PCE) and feedstock and solvent use in chemical manufacturing industries. Thus, it is crucial to implement technical improvements and better regulation strategies to reduce the evaporative losses of CCl4 occurring at the factory and/or process level.

Consumers and Intermediate Producers in the Phase-out of Agricultural and Industrial Ozone-Depleting Substances

2017 ◽  
Author(s):  
Alexander Ovodenko
Keyword(s):  
Methyl Bromide ◽  
Consumer Preferences ◽  
Market Competition ◽  
Montreal Protocol ◽  
Environmental Regime ◽  
Consumer Markets ◽  
Confounding Variables ◽  
Ozone Depleting Substances ◽  
Phase Out ◽  
The Impact

The chapter analyzes the impact of downstream consumer markets on environmental regime design by explaining why wealthy countries have successfully phased out industrial ozone-depleting substances (ODS) but not an agricultural pesticide known as methyl bromide under the Montreal Protocol, despite the 2005 phase-out deadline for that pesticide. Since the analysis focuses on the regulation of different sectors under the same treaty, it isolates the impact of markets without the threat of major confounding variables interfering with the conclusions. It emphasizes competitive pressures and the structure of intermediate producers in the industrial and agricultural markets employing ODS to explain why methyl bromide has been handled differently from industrial refrigerants. The findings illustrate the impacts of consumer preferences and market competition on the investments of fluoro-product companies and, in turn, on the policies of wealthy countries and rules in the ozone regime.

scholarly journals Emissions of CFCs, HCFCs and HFCs from India

2019 ◽  
Author(s):  
Daniel Say ◽  
Anita L. Ganesan ◽  
Mark F. Lunt ◽  
Matthew Rigby ◽  
Simon O'Doherty ◽  
...  
Keyword(s):  
Montreal Protocol ◽  
Emission Rates ◽  
Fugitive Emissions ◽  
Modelling Framework ◽  
Source Regions ◽  
Hfc 134A ◽  
Growing Economy ◽  
Ozone Depleting Substances ◽  
Global Emissions ◽  
Populous Country

Abstract. As the second most populous country and third fastest growing economy, India has emerged as a global economic power. As such, its emissions of greenhouse and ozone-depleting gases are of global significance. However, unlike neighbouring China, the Indian sub-continent is very poorly monitored by existing measurement networks. Of the greenhouse/ozone-depleting gases, India's emissions of synthetic halocarbons (here defined as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs)) are not well-known. Previous measurements from the region have been obtained at observatories many hundreds of miles from source regions, or at high altitudes, limiting their value for the estimation of regional emission rates. Given the projected rapid growth in demand for refrigerants in India, emission estimates of these halocarbons are urgently needed, to provide a benchmark against which future changes can be evaluated. In this study, we report the first atmospheric-measurement derived emissions of the ozone-depleting CFCs and HCFCs, and potent greenhouse gas HFCs from India. Air samples were collected at low-altitude during a 2-month aircraft campaign between June and July 2016. Emissions were derived from measurements of these samples using an inverse modelling framework and evaluated to assess India's progress in phasing out ozone-depleting substances (ODS) under the Montreal Protocol. Our CFC estimates show that India contributed 52 (26–83) Tg CO2eq yr−1, which were 7 (4–12) % of global emissions in 2016. HCFC-22 emissions at 7.8 (6.0–9.9) Gg yr−1 were of similar magnitude to emissions of HFC-134a (8.2 (6.1–10.7) Gg yr−1), suggesting that India used a range of HCFC and HFC refrigerants in 2016. We estimated India's HFC-23 emissions to be 1.2 (0.9–1.5) Gg yr−1 and our results are consistent with resumed venting of HFC-23 by HCFC-22 manufacturers following the discontinuation of funding for abatement under the Clean Development Mechanism. We report small emissions of HFC-32 and HFC-143a and provide evidence that HFC-32 emissions were primarily due to fugitive emissions during manufacturing processes. Lack of significant correlation among HFC species and the small emissions derived for HFC-32 and HFC-143a indicate that in 2016, India's use of refrigerant blends R-410A, R-404A and R-507A was limited, despite extensive consumption elsewhere in the world.

Global and regional emission estimates for three ozone-depleting hydrochlorofluoro-carbons (HCFCs) with no known end-uses

2020 ◽  
Author(s):  
Martin Vollmer ◽  
Keyword(s):  
Eastern China ◽  
Montreal Protocol ◽  
Lagrangian Model ◽  
Vienna Convention ◽  
Fully Integrated ◽  
First Results ◽  
Atmospheric Observations ◽  
Ozone Depleting Substances ◽  
Phase Out ◽  
Global Emissions

&lt;p&gt;We present first results on atmospheric abundances and inferred emissions of the previously undetected ozone depleting hydrochlorofluorocarbon HCFC-132b (1,2-dichloro-1,1-difluoroethane). In addition we report significant updates on observations and inferred emissions for HCFC-133a (2-chloro-1,1,1-trifluoroethane) and HCFC-31 (chlorofluoromethane). All three compounds are Ozone Depleting Substances (ODSs) and their productions are regulated under the Montreal Protocol on Substances that Deplete the Ozone Layer. However, they are not known as end-user products from which potential emissions to the atmosphere could occur. Rather, we hypothesize that the compounds are emitted as byproducts during the production of hydrofluorocarbons (HFCs). If this holds true, then the phase-out regulations of the Protocol do not apply to them, nevertheless the Protocol's overarching Vienna Convention encourages the parties to minimize such ODS byproduct emissions.&lt;/p&gt;&lt;p&gt;In-situ fully intercalibrated high-precision measurements of the recently discovered HCFC-132b have been made for several years at the stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) and are complemented with measurements from archived air samples (1978 &amp;#8211; present) of the Cape Grim Air Archive. Based on these measurements we reconstruct global HCFC-132b trends showing its first appearance in the atmosphere in the late 1990s, followed by a general growth in the atmosphere to current globally-averaged mole fractions of approx. 0.13 ppt (picomol mol&lt;sup&gt;-1&lt;/sup&gt;). Global emissions, which are derived from these observations using the AGAGE 12-box model, show a general increase to approx. 1 Gg yr&lt;sup&gt;-1&lt;/sup&gt; in 2019. Observation-based top-down regional emission estimates for the East-Asian region, as derived from a Bayesian inversion with the FLEXPART Lagrangian model, can explain all of the global emissions within the uncertainties of the method. Half of these emissions are allocated to Eastern China, a region where enhanced emissions for other ODSs were previously found. Emissions from Europe are comparably insignificant, but an analysis of the source locations supports the hypothesis that HCFC-132b emissions are a byproduct from HFC production. In addition to HCFC-132b, we present significant updates on observations of HCFC-133a and HCFC-31. HCFC-133a measurements are now fully integrated into the AGAGE network and provide a wealth of atmospheric observations. Similar to HCFC-132b, we show, for example, that abundances and global emissions of these two compounds have generally increased over the last few years.&lt;/p&gt;

Atmospheric impacts of short-lived chlorinated species over the recent past: a chemistry-climate perspective

2021 ◽  
Author(s):  
Ewa Bednarz ◽  
Ryan Hossaini ◽  
Luke Abraham ◽  
Peter Braesicke ◽  
Martyn Chipperfield
Keyword(s):  
Atmospheric Chemistry ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Lower Boundary ◽  
Montreal Protocol ◽  
Recent Past ◽  
Substantial Impact ◽  
Ozone Depleting Substances ◽  
The Impact

&lt;p&gt;The emissions of most long-lived halogenated ozone-depleting substances (ODSs) are now decreasing, owing to controls on their production introduced by Montreal Protocol and its amendments. However, short-lived halogenated compounds can also have substantial impact on atmospheric chemistry, including stratospheric ozone, particularly if emitted near climatological uplift regions. It has recently become evident that emissions of some chlorinated very short-lived species (VSLSs), such as chloroform (CHCl&lt;sub&gt;3&lt;/sub&gt;) and dichloromethane (CH&lt;sub&gt;2&lt;/sub&gt;Cl&lt;sub&gt;2&lt;/sub&gt;), could be larger than previously believed and increasing, particularly in Asia. While these may exert a significant influence on atmospheric chemistry and climate, their impacts remain poorly characterised.&amp;#160;&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;We address this issue using the UM-UKCA chemistry-climate model (CCM). While not only the first, to our knowledge, model study addressing this problem using a CCM, it is also the first such study employing a whole atmosphere model, thereby simulating the tropospheric Cl-VSLSs emissions and the resulting stratospheric impacts in a fully consistent manner. We use a newly developed Double-Extended Stratospheric-Tropospheric (DEST) chemistry scheme, which includes emissions of all major chlorinated and brominated VSLSs alongside an extended treatment of long-lived ODSs.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;We examine the impacts of rising Cl-VSLSs emissions on atmospheric chlorine tracers and ozone, including their long-term trends. We pay particular attention to the role of &amp;#8216;nudging&amp;#8217;, as opposed to the free-running model set up, for the simulated Cl-VSLSs impacts, thereby demostrating the role of atmospheric dynamics in modulating the atmospheric responses to Cl-VSLSs. In addition, we employ novel estimates of Cl-VSLS emissions over the recent past and compare the results with the simulations that prescribe Cl-VSLSs using simple lower boundary conditions. This allows us to demonstrate the impact such choice has on the dominant location and seasonality of the Cl-VSLSs transport into the stratosphere.&lt;/p&gt;

scholarly journals Options to accelerate ozone recovery: ozone and climate benefits

2010 ◽  
Vol 10 (16) ◽  
pp. 7697-7707 ◽  
Author(s):  
J. S. Daniel ◽  
E. L. Fleming ◽  
R. W. Portmann ◽  
G. J. M. Velders ◽  
C. H. Jackman ◽  
...  
Keyword(s):  
Ozone Depletion ◽  
Radiative Forcing ◽  
Montreal Protocol ◽  
N2o Emissions ◽  
Total Column Ozone ◽  
Potential Impact ◽  
Ozone Depleting Substances ◽  
Column Ozone ◽  
The Impact ◽  
Total Column

Abstract. Hypothetical reductions in future emissions of ozone-depleting substances (ODSs) and N2O are evaluated in terms of effects on equivalent effective stratospheric chlorine (EESC), globally-averaged total column ozone, and radiative forcing through 2100. Due to the established success of the Montreal Protocol, these actions can have only a fraction of the impact on ozone depletion that regulations already in force have had. If all anthropogenic ODS and N2O emissions were halted beginning in 2011, ozone is calculated to be higher by about 1–2% during the period 2030–2100 compared to a case of no additional restrictions. Direct radiative forcing by 2100 would be about 0.23 W/m2 lower from the elimination of anthropogenic N2O emissions and about 0.005 W/m2 lower from the destruction of the chlorofluorocarbon (CFC) bank. Due to the potential impact of N2O on future ozone levels, we provide an approach to incorporate it into the EESC formulation, which is used extensively in ozone depletion analyses. The ability of EESC to describe total ozone changes arising from additional ODS and N2O controls is also quantified.

Sustainable Tourism Policy Frameworks

2019 ◽  
Author(s):  
Alexandra Coghlan
Keyword(s):  
European Union ◽  
Sustainable Tourism ◽  
Ozone Layer ◽  
Montreal Protocol ◽  
Scientific Advice ◽  
Holy See ◽  
Policy Frameworks ◽  
Significant Achievement ◽  
Ozone Depleting Substances ◽  
Phase Out

Having looked at the external and internal challenges facing the move towards more sustainable tourism, and the impacts of tourism, you should now be wondering how sustainability in tourism can be turned into more than an ideal. Perhaps one of the most obvious way to achieve this is simply to regulate the sector. After all regulation worked for the ozone layer: scientists raised the alarm in the 1970s that a hole was appearing in the atmosphere’s ozone layer, caused by Ozone Depleting Substances or ODS (most notably CFCs) and resulting in adverse effects on human health and the environment. By 1987 the Montreal Protocol was established to phase out the use of ODS, and by June 2015, all countries in the United Nations, the Cook Islands, Holy See, Niue and the supranational European Union had ratified the original Protocol. The result was a 98% drop in ODS since ratification, and the hole is expected to have fully repaired itself by 2050. A significant achievement in terms of international cooperation, based on scientific advice.

scholarly journals Phase-out of high GWP refrigerants in refrigeration systems: Status of process in Colombia

Respuestas ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 65-74
Author(s):  
Juan José García Pabón
Keyword(s):  
Global Warming ◽  
Greenhouse Gases ◽  
Air Conditioning ◽  
Scientific Literature ◽  
High Potential ◽  
Paper Briefly ◽  
Production And Consumption ◽  
Ozone Depleting Substances ◽  
Phase Out ◽  
Very High

This article is intended to draw attention of the community in general to the changes that have taken place in refrigeration and air conditioning industry of the HFC refrigerants currently used. The HFCs are not Ozone-depleting substances, but the some HFCs are greenhouse gases with very high potential for global warming (GWPs). Thus, more than 150 countries sign up the Kigali Amendment in 2016, establishing the decreasing of the production and consumption of the HFCs. This paper briefly describes the problems surrounding the HFCs and summarizes the fluids considered as alternatives for the main HFCs used in refrigeration systems presented in the scientific literature. In addition, the outlook and the current situation of the HFC withdrawal process in Colombia are analyzed.

Improved characterisation of the impact of chlorinated VSLSs on atmospheric chemistry and climate: past, present and future

2020 ◽  
Author(s):  
Ewa Bednarz ◽  
Ryan Hossaini ◽  
Luke Abraham ◽  
Martyn Chipperfield
Keyword(s):  
Atmospheric Chemistry ◽  
Climate Model ◽  
Stratospheric Ozone ◽  
Montreal Protocol ◽  
Recent Past ◽  
Substantial Impact ◽  
Emissions Scenarios ◽  
Ozone Depleting Substances ◽  
The Impact ◽  
Future Emissions

&lt;p&gt;The emissions of most long-lived halogenated ozone-depleting substances (ODSs) are now decreasing, owing to controls on their production introduced by Montreal Protocol and its amendments. However, short-lived halogenated compounds can also have substantial impact on atmospheric chemistry, including stratospheric ozone, particularly if emitted near climatological uplift regions. It has recently become evident that emissions of some chlorinated very short-lived species (VSLSs), such as chloroform (CHCl&lt;sub&gt;3&lt;/sub&gt;) and dichloromethane (CH&lt;sub&gt;2&lt;/sub&gt;Cl&lt;sub&gt;2&lt;/sub&gt;), could be larger than previously believed and increasing, particularly in Asia. While these may exert a significant influence on atmospheric chemistry and climate, their impacts remain poorly characterised.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;We address this issue using the UM-UKCA chemistry-climate model. We use a newly developed Double-Extended Stratospheric-Tropospheric (DEST) chemistry scheme, which includes emissions of all major chlorinated and brominated VSLSs alongside an extended treatment of long-lived ODSs. Employing novel estimates of Cl-VSLS emissions we show model results regarding the atmospheric impacts of chlorinated VSLSs over the recent past (2000-present), with a focus on stratospheric ozone and HCl trends. Finally, we introduce our plans regarding examining the impacts of chlorinated VSLSs under a range of potential future emissions scenarios; the results of which will be directly relevant for the next WMO/UNEP assessment.&lt;/p&gt;

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