scholarly journals Recent increases in the atmospheric growth rate and emissions of HFC-23 (CHF<sub>3</sub>) and the link to HCFC-22 (CHClF<sub>2</sub>) production

2017 ◽  
Author(s):  
Peter G. Simmonds ◽  
Matthew Rigby ◽  
Archie McCulloch ◽  
Martin K. Vollmer ◽  
Stephan Henne ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Radiative Forcing ◽  
Average Rate ◽  
Time Frame ◽  
Atmospheric Gases ◽  
Annual Average ◽  
History Of ◽  
Global Emissions ◽  
Cape Grim

Abstract. High frequency measurements of the potent hydrofluorocarbon greenhouse gas CHF3 (HFC-23), a by-product of production of the hydrochlorofluorocarbon HCFC-22 (CHClF2), at five core stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, combined with measurements of firn and Cape Grim Air Archive (CGAA) air samples, are used to explore the changing atmospheric abundance of HFC-23. These measurements are used in combination with the AGAGE 2-D atmospheric 12-box model and a Bayesian inversion methodology to determine model atmospheric mole fractions and the atmospheric history of global HFC-23 emissions. The global modelled annual mole fraction of HFC-23 in the background atmosphere was 28.9 ± 0.6 pmol mol−1 at the end of 2016, representing a 28 % increase from 22.6 ± 0.4 pmol mol−1 in 2009. Over the same time frame, the modelled mole fraction of HCFC-22 increased by 19 % from 199 ± 2 pmol mol−1 to 237 ± 2 pmol mol−1. However, the annual average HCFC-22 growth rate decelerated from 2009 to 2016 at an annual average rate of 0.5 pmol mol−1 yr−2. Our results demonstrate that, following a minimum in HFC-23 global emissions in 2009 of 9.6 ± 0.6 Gg yr−1, emissions increased to a maximum in 2014 of 14.5 ± 0.6 Gg yr−1, declining to 12.7 ± 0.6 Gg yr−1 (157 Mt  CO2-eq. yr−1) in 2016. The 2009 emissions minimum is consistent with estimates based on national reports and is likely a response to the implementation of the Clean Development Mechanism (CDM) to mitigate HFC-23 emissions by incineration in developing (Non-Annex 1) countries under the Kyoto Protocol. Our derived cumulative emissions of HFC-23 during 2010–2016 were 89 ± 2 Gg (1.1 ± 0.2 Gt CO2-eq), which led to an increase in radiative forcing of 1.0 ± 0.1 mW m−2. Although the CDM had reduced global HFC-23 emissions, it cannot now offset the radiative forcing of higher emissions from increasing HCFC-22 production in Non-Annex 1 countries, as the CDM was closed to new entrants in 2009. We also find that the cumulative European HFC-23 emissions from 2010 to 2016 were ~ 1.3 Gg, corresponding to just 1.5 % of cumulative global HFC-23 emissions over this same period.

scholarly journals Recent increases in the atmospheric growth rate and emissions of HFC-23 (CHF<sub>3</sub>) and the link to HCFC-22 (CHClF<sub>2</sub>) production

2018 ◽  
Vol 18 (6) ◽  
pp. 4153-4169 ◽  
Author(s):  
Peter G. Simmonds ◽  
Matthew Rigby ◽  
Archie McCulloch ◽  
Martin K. Vollmer ◽  
Stephan Henne ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Radiative Forcing ◽  
Average Rate ◽  
Time Frame ◽  
Montreal Protocol ◽  
Atmospheric Gases ◽  
Annual Average ◽  
Air Samples ◽  
History Of

Abstract. High frequency measurements of trifluoromethane (HFC-23, CHF3), a potent hydrofluorocarbon greenhouse gas, largely emitted to the atmosphere as a by-product of the production of the hydrochlorofluorocarbon HCFC-22 (CHClF2), at five core stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, combined with measurements on firn air, old Northern Hemisphere air samples and Cape Grim Air Archive (CGAA) air samples, are used to explore the current and historic changes in the atmospheric abundance of HFC-23. These measurements are used in combination with the AGAGE 2-D atmospheric 12-box model and a Bayesian inversion methodology to determine model atmospheric mole fractions and the history of global HFC-23 emissions. The global modelled annual mole fraction of HFC-23 in the background atmosphere was 28.9 ± 0.6 pmol mol−1 at the end of 2016, representing a 28 % increase from 22.6 ± 0.4 pmol mol−1 in 2009. Over the same time frame, the modelled mole fraction of HCFC-22 increased by 19 % from 199 ± 2 to 237 ± 2 pmol mol−1. However, unlike HFC-23, the annual average HCFC-22 growth rate slowed from 2009 to 2016 at an annual average rate of −0.5 pmol mol−1 yr−2. This slowing atmospheric growth is consistent with HCFC-22 moving from dispersive (high fractional emissions) to feedstock (low fractional emissions) uses, with HFC-23 emissions remaining as a consequence of incomplete mitigation from all HCFC-22 production.Our results demonstrate that, following a minimum in HFC-23 global emissions in 2009 of 9.6 ± 0.6, emissions increased to a maximum in 2014 of 14.5 ± 0.6 Gg yr−1 and then declined to 12.7 ± 0.6 Gg yr−1 (157 Mt CO2 eq. yr−1) in 2016. The 2009 emissions minimum is consistent with estimates based on national reports and is likely a response to the implementation of the Clean Development Mechanism (CDM) to mitigate HFC-23 emissions by incineration in developing (non-Annex 1) countries under the Kyoto Protocol. Our derived cumulative emissions of HFC-23 during 2010–2016 were 89 ± 2 Gg (1.1 ± 0.2 Gt CO2 eq.), which led to an increase in radiative forcing of 1.0 ± 0.1 mW m−2 over the same period. Although the CDM had reduced global HFC-23 emissions, it cannot now offset the higher emissions from increasing HCFC-22 production in non-Annex 1 countries, as the CDM was closed to new entrants in 2009. We also find that the cumulative European HFC-23 emissions from 2010 to 2016 were  ∼  1.3 Gg, corresponding to just 1.5 % of cumulative global HFC-23 emissions over this same period. The majority of the increase in global HFC-23 emissions since 2010 is attributed to a delay in the adoption of mitigation technologies, predominantly in China and East Asia. However, a reduction in emissions is anticipated, when the Kigali 2016 amendment to the Montreal Protocol, requiring HCFC and HFC production facilities to introduce destruction of HFC-23, is fully implemented.

scholarly journals Global and regional emissions estimates of 1,1-difluoroethane (HFC-152a, CH<sub>3</sub>CHF<sub>2</sub>) from in situ and air archive observations

2016 ◽  
Vol 16 (1) ◽  
pp. 365-382 ◽  
Author(s):  
P. G. Simmonds ◽  
M. Rigby ◽  
A. J. Manning ◽  
M. F. Lunt ◽  
S. O'Doherty ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Average Rate ◽  
Stratospheric Ozone ◽  
Annual Average ◽  
Bottom Up ◽  
Rate Of Growth ◽  
Global Growth ◽  
Hfc 152A

Abstract. High frequency, in situ observations from 11 globally distributed sites for the period 1994–2014 and archived air measurements dating from 1978 onward have been used to determine the global growth rate of 1,1-difluoroethane (HFC-152a, CH3CHF2). These observations have been combined with a range of atmospheric transport models to derive global emission estimates in a top-down approach. HFC-152a is a greenhouse gas with a short atmospheric lifetime of about 1.5 years. Since it does not contain chlorine or bromine, HFC-152a makes no direct contribution to the destruction of stratospheric ozone and is therefore used as a substitute for the ozone depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). The concentration of HFC-152a has grown substantially since the first direct measurements in 1994, reaching a maximum annual global growth rate of 0.84 ± 0.05 ppt yr−1 in 2006, implying a substantial increase in emissions up to 2006. However, since 2007, the annual rate of growth has slowed to 0.38 ± 0.04 ppt yr−1 in 2010 with a further decline to an annual average rate of growth in 2013–2014 of −0.06 ± 0.05 ppt yr−1. The annual average Northern Hemisphere (NH) mole fraction in 1994 was 1.2 ppt rising to an annual average mole fraction of 10.1 ppt in 2014. Average annual mole fractions in the Southern Hemisphere (SH) in 1998 and 2014 were 0.84 and 4.5 ppt, respectively. We estimate global emissions of HFC-152a have risen from 7.3 ± 5.6 Gg yr−1 in 1994 to a maximum of 54.4 ± 17.1 Gg yr−1 in 2011, declining to 52.5 ± 20.1 Gg yr−1 in 2014 or 7.2 ± 2.8 Tg-CO2 eq yr−1. Analysis of mole fraction enhancements above regional background atmospheric levels suggests substantial emissions from North America, Asia, and Europe. Global HFC emissions (so called “bottom up” emissions) reported by the United Nations Framework Convention on Climate Change (UNFCCC) are based on cumulative national emission data reported to the UNFCCC, which in turn are based on national consumption data. There appears to be a significant underestimate ( >  20 Gg) of “bottom-up” reported emissions of HFC-152a, possibly arising from largely underestimated USA emissions and undeclared Asian emissions.

scholarly journals Global emissions of HFC-143a (CH<sub>3</sub>CF<sub>3</sub>) and HFC-32 (CH<sub>2</sub>F<sub>2</sub>) from in situ and air archive atmospheric observations

2014 ◽  
Vol 14 (17) ◽  
pp. 9249-9258 ◽  
Author(s):  
S. O'Doherty ◽  
M. Rigby ◽  
J. Mühle ◽  
D. J. Ivy ◽  
B. R. Miller ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Radiative Forcing ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Lower Troposphere ◽  
Emission Rates ◽  
Global Emission ◽  
Atmospheric Observations

Abstract. High-frequency, in situ observations from the Advanced Global Atmospheric Gases Experiment (AGAGE), for the period 2003 to 2012, combined with archive flask measurements dating back to 1977, have been used to capture the rapid growth of HFC-143a (CH3CF3) and HFC-32 (CH2F2) mole fractions and emissions into the atmosphere. Here we report the first in situ global measurements of these two gases. HFC-143a and HFC-32 are the third and sixth most abundant hydrofluorocarbons (HFCs) respectively and they currently make an appreciable contribution to the HFCs in terms of atmospheric radiative forcing (1.7 ± 0.04 and 0.7 ± 0.02 mW m−2 in 2012 respectively). In 2012 the global average mole fraction of HFC-143a was 13.4 ± 0.3 ppt (1σ) in the lower troposphere and its growth rate was 1.4 ± 0.04 ppt yr−1; HFC-32 had a global mean mole fraction of 6.2 ± 0.2 ppt and a growth rate of 1.1 ± 0.04 ppt yr−1 in 2012. The extensive observations presented in this work have been combined with an atmospheric transport model to simulate global atmospheric abundances and derive global emission estimates. It is estimated that 23 ± 3 Gg yr−1 of HFC-143a and 21 ± 11 Gg yr−1 of HFC-32 were emitted globally in 2012, and the emission rates are estimated to be increasing by 7 ± 5% yr−1 for HFC-143a and 14 ± 11% yr−1 for HFC-32.

scholarly journals Global emissions of HFC-143a (CH<sub>3</sub>CF<sub>3</sub>) and HFC-32 (CH<sub>2</sub>F<sub>2</sub>) from in situ and air archive atmospheric observations

2014 ◽  
Vol 14 (5) ◽  
pp. 6471-6500 ◽  
Author(s):  
S. O'Doherty ◽  
M. Rigby ◽  
J. Mühle ◽  
D. J. Ivy ◽  
B. R. Miller ◽  
...  
Keyword(s):  
Growth Rate ◽  
Mole Fraction ◽  
Radiative Forcing ◽  
Transport Model ◽  
Atmospheric Transport ◽  
Lower Troposphere ◽  
Emission Rates ◽  
Global Emission ◽  
Atmospheric Observations

Abstract. High frequency, in situ observations from the Advanced Global Atmospheric Gases Experiment (AGAGE), for the period 2003 to 2012, combined with archive flask measurements dating back to 1977, have been used to capture the rapid growth of HFC-143a (CH3CF3) and HFC-32 (CH2F2) mole fractions and emissions into the atmosphere. Here we report the first in situ global measurements of these two gases. HFC-143a and HFC-32 are the third and sixth most abundant HFCs respectively and they currently make an appreciable contribution to the HFCs in terms of atmospheric radiative forcing (1.7 and 0.7 mW m2 in 2012, respectively). In 2012 the global average mole fraction of HFC-143a was 13.4 ± 0.3 ppt (1-sigma) in the lower troposphere and its growth rate was 1.4 ± 0.04 ppt yr−1; HFC-32 had a global mean mole fraction of 6.2 ± 0.2 ppt and a growth rate of 1.1 ± 0.04 ppt yr−1 in 2012. The extensive observations presented in this work have been combined with an atmospheric transport model to simulate global atmospheric abundances and derive global emission estimates. It is estimated that 23 ± 3 Gg yr−1 of HFC-143a and 21 ± 11 Gg yr−1 of HFC-32 were emitted globally in 2012, and the emission rates are estimated to be increasing 7 ± 5% yr−1 for HFC-143a and 14 ± 11% yr−1 for HFC-32.

scholarly journals History of atmospheric SF<sub>6</sub> from 1973 to 2008

2010 ◽  
Vol 10 (5) ◽  
pp. 13519-13555
Author(s):  
M. Rigby ◽  
J. Mühle ◽  
B. R. Miller ◽  
R. G. Prinn ◽  
P. B. Krummel ◽  
...  
Keyword(s):  
Growth Rate ◽  
Sulfur Hexafluoride ◽  
Transport Model ◽  
In Situ Monitoring ◽  
Electron Capture Detection ◽  
Monitoring Site ◽  
Emission Rates ◽  
Chemical Transport Model ◽  
History Of ◽  
Global Emissions

Abstract. We present atmospheric sulfur hexafluoride (SF6) mole fractions and emissions estimates from the 1970s to 2008. Measurements were made of archived air samples starting from 1973 in the Northern Hemisphere and from 1978 in the Southern Hemisphere, using the Advanced Global Atmospheric Gases Experiment (AGAGE) gas chromatographic–mass spectrometric (GC-MS) systems. These measurements were combined with modern high-frequency GC-MS and GC-electron capture detection (ECD) data from AGAGE monitoring sites, to produce a unique air history of this potent greenhouse gas. Atmospheric mole fractions were found to have increased by more than an order of magnitude between 1973 and 2008. The 2008 growth rate was found to be the highest recorded, at 0.29 ± 0.02 pmol mol−1 yr−1. A three-dimensional chemical transport model and a minimum variance Bayesian inverse method was used to estimate annual emission rates using the measurements. Consistent with the mole fraction growth rate maximum, global emissions during 2008 were also found to be highest in the 1973–2008 period, reaching 7.5 ± 0.4 Ggyr−1 and surpassing the previous maximum in 1995. The 2008 values follow an increase in emissions of 50 ± 25% since 2000. A second global inversion which also incorporated National Oceanic and Atmospheric Administration (NOAA) flask measurements and in situ monitoring site data was found to agree well with the emissions derived using AGAGE measurements alone. By estimating continent-scale emissions using all available AGAGE and NOAA surface measurements covering the period 2004–2008, we find that it is likely that much of the global emissions rise during this five-year period originated primarily from Asian countries that do not report emissions to the United Nations Framework Convention on Climate Change (UNFCCC). We also find it likely that SF6 emissions reported to the UNFCCC were underestimated between at least 2004 and 2007.

scholarly journals Accelerating growth of HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane) in the atmosphere

2010 ◽  
Vol 10 (13) ◽  
pp. 5903-5910 ◽  
Author(s):  
J. C. Laube ◽  
P. Martinerie ◽  
E. Witrant ◽  
T. Blunier ◽  
J. Schwander ◽  
...  
Keyword(s):  
Growth Rate ◽  
High Altitude ◽  
Bottom Up ◽  
Present Evidence ◽  
Air Samples ◽  
Upper Troposphere ◽  
Mixing Ratios ◽  
History Of ◽  
Global Emissions

Abstract. We report the first measurements of 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), a substitute for ozone depleting compounds, in air samples originating from remote regions of the atmosphere and present evidence for its accelerating growth. Observed mixing ratios ranged from below 0.01 ppt in deep firn air to 0.59 ppt in the current northern mid-latitudinal upper troposphere. Firn air samples collected in Greenland were used to reconstruct a history of atmospheric abundance. Year-on-year increases were deduced, with acceleration in the growth rate from 0.029 ppt per year in 2000 to 0.056 ppt per year in 2007. Upper tropospheric air samples provide evidence for a continuing growth until late 2009. Furthermore we calculated a stratospheric lifetime of 370 years from measurements of air samples collected on board high altitude aircraft and balloons. Emission estimates were determined from the reconstructed atmospheric trend and suggest that current "bottom-up" estimates of global emissions for 2005 are too high by a factor of three.

scholarly journals Rapid growth of HFC-227ea (1,1,1,2,3,3,3-Heptafluoropropane) in the atmosphere

2010 ◽  
Vol 10 (3) ◽  
pp. 7675-7697
Author(s):  
J. C. Laube ◽  
P. Martinerie ◽  
E. Witrant ◽  
T. Blunier ◽  
J. Schwander ◽  
...  
Keyword(s):  
Growth Rate ◽  
High Altitude ◽  
Rapid Growth ◽  
Bottom Up ◽  
Present Evidence ◽  
Air Samples ◽  
Upper Troposphere ◽  
Mixing Ratios ◽  
History Of ◽  
Global Emissions

Abstract. We report the first measurements of 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), a substitute for ozone depleting compounds, in remote regions of the atmosphere and present evidence for its rapid growth. Observed mixing ratios ranged from below 0.01 ppt in deep firn air to 0.59 ppt in the northern mid-latitudinal upper troposphere. Firn air samples collected in Greenland were used to reconstruct a history of atmospheric abundance. Year-on-year increases were deduced, with acceleration in the growth rate from 0.026 ppt per year in 2000 to 0.057 ppt per year in 2007. Upper tropospheric air samples provide evidence for a continuing growth until late 2009. Furthermore we calculated a stratospheric lifetime of 370 years from measurements of air samples collected on board high altitude aircraft and balloons. Emission estimates were determined from the reconstructed atmospheric trend and suggest that current "bottom-up" estimates of global emissions for 2005 are too high by more than a factor of three.

The perils and dangers of these knights (and undead peasants): Interpreting English and Scottish Extent Rolls of 1297–1305

2016 ◽  
Vol 36 (1) ◽  
pp. 13-39 ◽  
Author(s):  
J. Donnelly
Keyword(s):  
Social History ◽  
Economic History ◽  
Time Frame ◽  
Compte Rendu ◽  
History Of ◽  
Different Sources

Medieval Scottish economic and social history has held little interest for a unionist establishment but, just when a recovery of historic independence begins to seem possible, this paper tackles a (perhaps the) key pre-1424 source. It is compared with a Rutland text, in a context of foreign history, both English and continental. The Berwickshire text is not, as was suggested in 2014, a ‘compte rendu’ but rather an ‘extent’, intended to cross-check such accounts. Read alongside the Rutland roll, it is not even a single ‘compte’ but rather a palimpsest of different sources and times: a possibility beyond earlier editorial imaginings. With content falling (largely) within the time-frame of the PoMS project (although not actually included), when the economic history of Scotland in Europe is properly explored, the sources discussed here will be key and will offer an interesting challenge to interpretation. And some surprises about their nature and date.

The Aristocracy in England and Tuscany, 1000 - 1250

2019 ◽  
Author(s):  
Peter Coss
Keyword(s):  
Time Frame ◽  
Grand Narrative ◽  
English History ◽  
Internal Dynamics ◽  
Italian Experience ◽  
English Society ◽  
History Of ◽  
External Stimuli ◽  
The Relationship ◽  
Interpretative Framework

Part I of this book is an in-depth examination of the characteristics of the Tuscan aristocracy across the first two and a half centuries of the second millennium, as studied by Italian historians and others working within the Italian tradition: their origins, interests, strategies for survival and exercise of power; the structure and the several levels of aristocracy and how these interrelated; the internal dynamics and perceptions that governed aristocratic life; and the relationship to non-aristocratic sectors of society. It will look at how aristocratic society changed across this period and how far changes were internally generated as opposed to responses from external stimuli. The relationship between the aristocracy and public authority will also be examined. Part II of the book deals with England. The aim here is not a comparative study but to bring insights drawn from Tuscan history and Tuscan historiography into play in understanding the evolution of English society from around the year 1000 to around 1250. This part of the book draws on the breadth of English historiography but is also guided by the Italian experience. The book challenges the interpretative framework within which much English history of this period tends to be written—that is to say the grand narrative which revolves around Magna Carta and English exceptionalism—and seeks to avoid dangers of teleology, of idealism, and of essentialism. By offering a study of the aristocracy across a wide time-frame and with themes drawn from Italian historiography, I hope to obviate these tendencies and to appreciate the aristocracy firmly within its own contexts.

scholarly journals Overview of the NOAA/ESRL Federated Aerosol Network

2019 ◽  
Vol 100 (1) ◽  
pp. 123-135 ◽  
Author(s):  
Elisabeth Andrews ◽  
Patrick J. Sheridan ◽  
John A. Ogren ◽  
Derek Hageman ◽  
Anne Jefferson ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Data Access ◽  
Department Of Energy ◽  
Atmospheric Measurements ◽  
Aerosol Radiative Forcing ◽  
Cooperative Program ◽  
Observation Strategy ◽  
The World ◽  
History Of ◽  
Foreign Science

AbstractTo estimate global aerosol radiative forcing, measurements of aerosol optical properties are made by the National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory (ESRL)’s Global Monitoring Division (GMD) and their collaborators at 30 monitoring locations around the world. Many of the sites are located in regions influenced by specific aerosol types (Asian and Saharan desert dust, Asian pollution, biomass burning, etc.). This network of monitoring stations is a shared endeavor of NOAA and many collaborating organizations, including the World Meteorological Organization (WMO)’s Global Atmosphere Watch (GAW) program, the U.S. Department of Energy (DOE), several U.S. and foreign universities, and foreign science organizations. The result is a long-term cooperative program making atmospheric measurements that are directly comparable with those from all the other network stations and with shared data access. The protocols and software developed to support the program facilitate participation in GAW’s atmospheric observation strategy, and the sites in the NOAA/ESRL network make up a substantial subset of the GAW aerosol observations. This paper describes the history of the NOAA/ESRL Federated Aerosol Network, details about measurements and operations, and some recent findings from the network measurements.

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