Direct atmospheric 14 CO 2 measurements began in New Zealand in 1954, initially to improve 14 C a... more Direct atmospheric 14 CO 2 measurements began in New Zealand in 1954, initially to improve 14 C as a dating tool, but quickly evolving into a method for understanding the carbon cycle. These early 14 CO 2 measurements immediately demonstrated the existence of an "Atom Bomb Effect," as well as an "Industrial Effect." These two gigantic tracer experiments have been utilized via 14 CO 2 measurements over the years to produce a wealth of knowledge in multiple research fields including atmospheric carbon cycle research, oceanography, soil science, and aging of post-bomb materials.
We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Ba... more We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Baring Head, New Zealand, filtered for steady background CO 2 mole fractions during southerly wind conditions. We discuss relationships between variability in the filtered CO 2 time series and regional to global carbon cycling. Baring Head is well situated to sample air that has been isolated from terrestrial influences over the Southern Ocean, and experiences extended episodes of strong southerly winds with low CO 2 variability. The filtered Baring Head CO 2 record reveals an average seasonal cycle with amplitude of 0.95 ppm that is 13 % smaller and 3 weeks earlier in phase than that at the South Pole. Seasonal variations in a given year are sensitive to the timing and magnitude of the combined influences of Southern Ocean CO 2 fluxes and terrestrial fluxes from both hemispheres. The amplitude of the seasonal cycle varies throughout the record, but we find no significant long-term seasonal changes with respect to the South Pole. Interannual variations in CO 2 growth rate in the Baring Head record closely match the El Niño-Southern Oscillation, reflecting the global reach of CO 2 mole fraction anomalies associated with this cycle. We use atmospheric transport model results to investigate contributions to seasonal and annual-mean components of the observed CO 2 record. Long-term trends in mean gradients between Baring Head and other stations are predominately due to increases in Northern Hemisphere fossil-fuel burning and Southern Ocean CO 2 uptake, for which there remains a wide range of future estimates. We find that the postulated recent reduction in the efficiency of Southern Ocean anthropogenic CO 2 uptake, as a result of increased zonal winds, is too small to be detectable as significant differences in atmospheric CO 2 between mid to high latitude Southern Hemisphere observing stations.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2021
The causes of methane's renewed rise since 2007, accelerated growth from 2014 and record rise... more The causes of methane's renewed rise since 2007, accelerated growth from 2014 and record rise in 2020, concurrent with an isotopic shift to values more depleted in 13 C, remain poorly understood. This rise is the dominant departure from greenhouse gas scenarios that limit global heating to less than 2°C. Thus a comprehensive understanding of methane sources and sinks, their trends and inter-annual variations are becoming more urgent. Efforts to quantify both sources and sinks and understand latitudinal and seasonal variations will improve our understanding of the methane cycle and its anthropogenic component. Nationally declared emissions inventories under the UN Framework Convention on Climate Change (UNFCCC) and promised contributions to emissions reductions under the UNFCCC Paris Agreement need to be verified independently by top-down observation. Furthermore, indirect effects on natural emissions, such as changes in aquatic ecosystems, also need to be quantified. Nitrous oxi...
Distribution profiles of radiocarbon in dissolved inorganic carbonate have been measured along tw... more Distribution profiles of radiocarbon in dissolved inorganic carbonate have been measured along two transects in the southern Pacific, east of New Zealand. Use of accelerator mass spectrometry, with its small-sample-size capability, made it possible to sample near-surface waters with a depth resolution of a few tens of meters. Sampling of deeper water was guided by salinity and temperature data transmitted by a conductivity-temperature-depth probe. The measurements, taken over the Chatham Rise, show highly structured profiles that can be correlated with known circulation patterns in this region.
These Frequently Asked Questions have been taken directly from the chapters of the underlying rep... more These Frequently Asked Questions have been taken directly from the chapters of the underlying report and are collected here.
Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui... more Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l'attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall'Ipcc-Comitato intergovernativo sui cambiamenti climatici-che illustra la sintesi delle ricerche svolte su questo tema rilevante. a cura di Stefano Schiavon, Roberto Zecchin I cambiamenti climatici CDA • n. 9 ottobre 2007• www.reedbusiness.it Ambiente-Intergovernmental Panel on Climate Change
We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Ba... more We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Baring Head, New Zealand, filtered for steady background CO 2 mole fractions during southerly wind conditions. We discuss relationships between variability in the filtered CO 2 time series and regional to global carbon cycling. Baring Head is well situated to sample air that has been isolated from terrestrial influences over the Southern Ocean, and experiences extended episodes of strong southerly winds with low CO 2 variability. The filtered Baring Head CO 2 record reveals an average seasonal cycle with amplitude of 0.95 ppm that is 13 % smaller and 3 weeks earlier in phase than that at the South Pole. Seasonal variations in a given year are sensitive to the timing and magnitude of the combined influences of Southern Ocean CO 2 fluxes and terrestrial fluxes from both hemispheres. The amplitude of the seasonal cycle varies throughout the record, but we find no significant long-term seasonal changes with respect to the South Pole. Interannual variations in CO 2 growth rate in the Baring Head record closely match the El Niño-Southern Oscillation, reflecting the global reach of CO 2 mole fraction anomalies associated with this cycle. We use atmospheric transport model results to investigate contributions to seasonal and annual-mean components of the observed CO 2 record. Long-term trends in mean gradients between Baring Head and other stations are predominately due to increases in Northern Hemisphere fossil-fuel burning and Southern Ocean CO 2 uptake, for which there remains a wide range of future estimates. We find that the postulated recent reduction in the efficiency of Southern Ocean anthropogenic CO 2 uptake, as a result of increased zonal winds, is too small to be detectable as significant differences in atmospheric CO 2 between mid to high latitude Southern Hemisphere observing stations.
We present descriptions of the in situ instrumentation, calibration procedures, intercomparison e... more We present descriptions of the in situ instrumentation, calibration procedures, intercomparison efforts, and data filtering methods used in a 39-yr record of continuous atmospheric carbon dioxide (CO 2) observations made at Baring Head, New Zealand. Located on the southern coast of the North Island, Baring Head is exposed to extended periods of strong air flow from the south with minimal terrestrial influence resulting in low CO 2 variability. The site is therefore well suited for sampling air masses that are representative of the Southern Ocean region. Instrumental precision is better than 0.015 ppm (1-σ) on 1-Hz values. Comparisons to over 600 co-located flask samples, as well as laboratory based flask and cylinder comparison exercises, suggest that over recent decades compatibility with respect to the Scripps Institution of Oceanography (SIO) and World Meteorological Organisation (WMO) CO 2 scales has been 0.3 ppm or better.
Modelling 263 4.2.6.1 Laboratory data and the OH lifetime of greenhouse gases 263 4.2.6.2 Atmosph... more Modelling 263 4.2.6.1 Laboratory data and the OH lifetime of greenhouse gases 263 4.2.6.2 Atmospheric measurements and modelling of photochemistry 264 4.3 Projections of Future Emissions 266 4.3.1 The Adjusted/Augmented IPCC/SRES Emission Scenarios 266 4.3.2 Shifting Regional Emissions of NO x , CO and VOC in 2100 4.3.3 Projections of Natural Emissions in 2100 4.4 Projections of Atmospheric Composition for the 21st Century 4.4.1 Introduction 4.4.2 The OxComp Workshop 4.4.3 Testing CTM Simulation of the Current (Y2000) Atmosphere 4.4.4 Model Simulations of Perturbed and Y2100 Atmospheres 4.4.5 Atmospheric Composition for the IPCC Scenarios to 2100 4.4.6 Gaps in These Projections-the Need for Coupled Models 4.4.7 Sensitivity Analysis for Individual Sectors 4.5 Open Questions 4.5.1 Chemical Processes Important on the Global Scale 4.5.1.1 Missing chemistry, representation of small scales, and changing emission patterns 4.5.1.2 Aerosol interactions with tropospheric O 3 and OH 4.5.1.3 Stratosphere-troposphere coupling 4.5.1.4 Uncertainties in the tropospheric O 3 budget 4.5.2 Impacts of Physical Climate Change on Atmospheric Chemistry 4.5.3 Feedbacks through Natural Emissions 4.6 Overall Impact of Global Atmospheric Chemistry Change References
The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the go... more The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the goals of the 2015 United Nations Framework Convention on Climate Change Paris Agreement. Urgent action is required to bring methane back to a pathway more in line with the Paris goals. Emission reduction from “tractable” (easier to mitigate) anthropogenic sources such as the fossil fuel industries and landfills is being much facilitated by technical advances in the past decade, which have radically improved our ability to locate, identify, quantify, and reduce emissions. Measures to reduce emissions from “intractable” (harder to mitigate) anthropogenic sources such as agriculture and biomass burning have received less attention and are also becoming more feasible, including removal from elevated‐methane ambient air near to sources. The wider effort to use microbiological and dietary intervention to reduce emissions from cattle (and humans) is not addressed in detail in this essentially geo...
Given the number of recent papers that have proposed quite different explanations for the post-20... more Given the number of recent papers that have proposed quite different explanations for the post-2006 rise in atmospheric CH4, it is clear that there are still some major systemic uncertainties in our understanding of the CH4 source – sink budget. While the increasing amount of isotopic (δ CH4) data should help to resolve these uncertainties, this has to deal with a limited understanding of removal by Cl with its very large kinetic isotope effect (KIE), and so a significant effect on δCH4 even though most of CH4 removal is by OH.
Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), ... more Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), 2016 (7.0 ± 0.7 ppb/year), and 2017 (7.7 ± 0.7 ppb/year), at rates not observed since the 1980s. The increase in the methane burden began in 2007, with the mean global mole fraction in remote surface background air rising from about 1,775 ppb in 2006 to 1,850 ppb in 2017. Simultaneously the 13 C/ 12 C isotopic ratio (expressed as δ 13 C CH4) has shifted, has shifted, now trending negative for more than a decade. The causes of methane's recent mole fraction increase are therefore either a change in the relative proportions (and totals) of emissions from biogenic and thermogenic and pyrogenic sources, especially in the tropics and subtropics, or a decline in the atmospheric sink of methane, or both. Unfortunately, with limited measurement data sets, it is not currently possible to be more definitive. The climate warming impact of the observed methane increase over the past decade, if continued at >5 ppb/year in the coming decades, is sufficient to challenge the Paris Agreement, which requires sharp cuts in the atmospheric methane burden. However, anthropogenic methane emissions are relatively very large and thus offer attractive targets for rapid reduction, which are essential if the Paris Agreement aims are to be attained. Plain Language Summary The rise in atmospheric methane (CH 4), which began in 2007, accelerated in the past 4 years. The growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the carbon isotope ratio of the methane. The causes of the rise are not fully understood, and may include increased emissions and perhaps a decline in the destruction of methane in the air. Methane's increase since 2007 was not expected in future greenhouse gas scenarios compliant with the targets of the Paris Agreement, and if the increase continues at the same rates it may become very difficult to meet the Paris goals. There is now urgent need to reduce methane emissions, especially from the fossil fuel industry.
Future changes in New Zealand’s climate are expected to be less than in many other countries, and... more Future changes in New Zealand’s climate are expected to be less than in many other countries, and New Zealand has well established governance structures for dealing with environmental risks. While this might imply that adaptation would be straightforward, extensive public and private investments, as well as many traditional Māori assets and cultural values, are in areas increasingly at risk of flooding and sea level rise. In order to consider the country’s adaptive capacity in more detail, we have used an empirical research approach, working with government practitioners at three levels and with Māori communities.
Very different perceptions of risk, and structural inertia in planning processes have emerged as key issues for implementing adaptation responses. In particular, the use of static frameworks biases responses towards retrospective, rather than anticipatory analysis. Ongoing socioeconomic changes in New Zealand also raise the risk of structural effects caused by climate change impacts becoming unevenly distributed across society. Our analysis indicates that a national and regional strategic approach, centred on a dynamic view of climate risk, is necessary for effective decisions at the local government and community level. In addition, effective adaptation requires better identification of barriers and opportunities for addressing changing risk, together with more effective and continuous social engagement.
Since 1986 the Atmospheric Environment Service (AES) of Environment Canada has operated an atmosp... more Since 1986 the Atmospheric Environment Service (AES) of Environment Canada has operated an atmospheric chemistry program at Station Alert, which is located at 82°N on the northern tip of Ellesmere Island.The program provides a detailed record of atmospheric change in the high Arctic that is crucial to both regional and global issues. Plans to reduce the Canadian government's deficit now require Environment Canada to make budgetary cuts and are prompting reevaluation of this and other programs. In light of these circumstances, we would like to take the opportunity to consider the importance of Alert to international atmospheric science.
Lenny Bernstein, Peter Bosch, Osvaldo Canziani, Zhenlin Chen, Renate Christ, Ogunlade Davidson, W... more Lenny Bernstein, Peter Bosch, Osvaldo Canziani, Zhenlin Chen, Renate Christ, Ogunlade Davidson, William Hare, Saleemul Huq, David Karoly, Vladimir Kattsov, Zbigniew Kundzewicz, Jian Liu, Ulrike Lohmann, Martin Manning, Taroh Matsuno, Bettina Menne, Bert Metz, Monirul Mirza, Neville Nicholls, Leonard Nurse, Rajendra Pachauri, Jean Palutikof, Martin Parry, Dahe Qin, Nijavalli Ravindranath, Andy Reisinger, Jiawen Ren, Keywan Riahi, Cynthia Rosenzweig, Matilde Rusticucci, Stephen Schneider, Youba Sokona, Susan Solomon, Peter Stott, Ronald Stouffer, Taishi Sugiyama, Rob Swart, Dennis Tirpak, Coleen Vogel, Gary Yohe
Direct atmospheric 14 CO 2 measurements began in New Zealand in 1954, initially to improve 14 C a... more Direct atmospheric 14 CO 2 measurements began in New Zealand in 1954, initially to improve 14 C as a dating tool, but quickly evolving into a method for understanding the carbon cycle. These early 14 CO 2 measurements immediately demonstrated the existence of an "Atom Bomb Effect," as well as an "Industrial Effect." These two gigantic tracer experiments have been utilized via 14 CO 2 measurements over the years to produce a wealth of knowledge in multiple research fields including atmospheric carbon cycle research, oceanography, soil science, and aging of post-bomb materials.
We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Ba... more We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Baring Head, New Zealand, filtered for steady background CO 2 mole fractions during southerly wind conditions. We discuss relationships between variability in the filtered CO 2 time series and regional to global carbon cycling. Baring Head is well situated to sample air that has been isolated from terrestrial influences over the Southern Ocean, and experiences extended episodes of strong southerly winds with low CO 2 variability. The filtered Baring Head CO 2 record reveals an average seasonal cycle with amplitude of 0.95 ppm that is 13 % smaller and 3 weeks earlier in phase than that at the South Pole. Seasonal variations in a given year are sensitive to the timing and magnitude of the combined influences of Southern Ocean CO 2 fluxes and terrestrial fluxes from both hemispheres. The amplitude of the seasonal cycle varies throughout the record, but we find no significant long-term seasonal changes with respect to the South Pole. Interannual variations in CO 2 growth rate in the Baring Head record closely match the El Niño-Southern Oscillation, reflecting the global reach of CO 2 mole fraction anomalies associated with this cycle. We use atmospheric transport model results to investigate contributions to seasonal and annual-mean components of the observed CO 2 record. Long-term trends in mean gradients between Baring Head and other stations are predominately due to increases in Northern Hemisphere fossil-fuel burning and Southern Ocean CO 2 uptake, for which there remains a wide range of future estimates. We find that the postulated recent reduction in the efficiency of Southern Ocean anthropogenic CO 2 uptake, as a result of increased zonal winds, is too small to be detectable as significant differences in atmospheric CO 2 between mid to high latitude Southern Hemisphere observing stations.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2021
The causes of methane's renewed rise since 2007, accelerated growth from 2014 and record rise... more The causes of methane's renewed rise since 2007, accelerated growth from 2014 and record rise in 2020, concurrent with an isotopic shift to values more depleted in 13 C, remain poorly understood. This rise is the dominant departure from greenhouse gas scenarios that limit global heating to less than 2°C. Thus a comprehensive understanding of methane sources and sinks, their trends and inter-annual variations are becoming more urgent. Efforts to quantify both sources and sinks and understand latitudinal and seasonal variations will improve our understanding of the methane cycle and its anthropogenic component. Nationally declared emissions inventories under the UN Framework Convention on Climate Change (UNFCCC) and promised contributions to emissions reductions under the UNFCCC Paris Agreement need to be verified independently by top-down observation. Furthermore, indirect effects on natural emissions, such as changes in aquatic ecosystems, also need to be quantified. Nitrous oxi...
Distribution profiles of radiocarbon in dissolved inorganic carbonate have been measured along tw... more Distribution profiles of radiocarbon in dissolved inorganic carbonate have been measured along two transects in the southern Pacific, east of New Zealand. Use of accelerator mass spectrometry, with its small-sample-size capability, made it possible to sample near-surface waters with a depth resolution of a few tens of meters. Sampling of deeper water was guided by salinity and temperature data transmitted by a conductivity-temperature-depth probe. The measurements, taken over the Chatham Rise, show highly structured profiles that can be correlated with known circulation patterns in this region.
These Frequently Asked Questions have been taken directly from the chapters of the underlying rep... more These Frequently Asked Questions have been taken directly from the chapters of the underlying report and are collected here.
Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui... more Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l'attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall'Ipcc-Comitato intergovernativo sui cambiamenti climatici-che illustra la sintesi delle ricerche svolte su questo tema rilevante. a cura di Stefano Schiavon, Roberto Zecchin I cambiamenti climatici CDA • n. 9 ottobre 2007• www.reedbusiness.it Ambiente-Intergovernmental Panel on Climate Change
We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Ba... more We present an analysis of a 39-year record of continuous atmospheric CO 2 observations made at Baring Head, New Zealand, filtered for steady background CO 2 mole fractions during southerly wind conditions. We discuss relationships between variability in the filtered CO 2 time series and regional to global carbon cycling. Baring Head is well situated to sample air that has been isolated from terrestrial influences over the Southern Ocean, and experiences extended episodes of strong southerly winds with low CO 2 variability. The filtered Baring Head CO 2 record reveals an average seasonal cycle with amplitude of 0.95 ppm that is 13 % smaller and 3 weeks earlier in phase than that at the South Pole. Seasonal variations in a given year are sensitive to the timing and magnitude of the combined influences of Southern Ocean CO 2 fluxes and terrestrial fluxes from both hemispheres. The amplitude of the seasonal cycle varies throughout the record, but we find no significant long-term seasonal changes with respect to the South Pole. Interannual variations in CO 2 growth rate in the Baring Head record closely match the El Niño-Southern Oscillation, reflecting the global reach of CO 2 mole fraction anomalies associated with this cycle. We use atmospheric transport model results to investigate contributions to seasonal and annual-mean components of the observed CO 2 record. Long-term trends in mean gradients between Baring Head and other stations are predominately due to increases in Northern Hemisphere fossil-fuel burning and Southern Ocean CO 2 uptake, for which there remains a wide range of future estimates. We find that the postulated recent reduction in the efficiency of Southern Ocean anthropogenic CO 2 uptake, as a result of increased zonal winds, is too small to be detectable as significant differences in atmospheric CO 2 between mid to high latitude Southern Hemisphere observing stations.
We present descriptions of the in situ instrumentation, calibration procedures, intercomparison e... more We present descriptions of the in situ instrumentation, calibration procedures, intercomparison efforts, and data filtering methods used in a 39-yr record of continuous atmospheric carbon dioxide (CO 2) observations made at Baring Head, New Zealand. Located on the southern coast of the North Island, Baring Head is exposed to extended periods of strong air flow from the south with minimal terrestrial influence resulting in low CO 2 variability. The site is therefore well suited for sampling air masses that are representative of the Southern Ocean region. Instrumental precision is better than 0.015 ppm (1-σ) on 1-Hz values. Comparisons to over 600 co-located flask samples, as well as laboratory based flask and cylinder comparison exercises, suggest that over recent decades compatibility with respect to the Scripps Institution of Oceanography (SIO) and World Meteorological Organisation (WMO) CO 2 scales has been 0.3 ppm or better.
Modelling 263 4.2.6.1 Laboratory data and the OH lifetime of greenhouse gases 263 4.2.6.2 Atmosph... more Modelling 263 4.2.6.1 Laboratory data and the OH lifetime of greenhouse gases 263 4.2.6.2 Atmospheric measurements and modelling of photochemistry 264 4.3 Projections of Future Emissions 266 4.3.1 The Adjusted/Augmented IPCC/SRES Emission Scenarios 266 4.3.2 Shifting Regional Emissions of NO x , CO and VOC in 2100 4.3.3 Projections of Natural Emissions in 2100 4.4 Projections of Atmospheric Composition for the 21st Century 4.4.1 Introduction 4.4.2 The OxComp Workshop 4.4.3 Testing CTM Simulation of the Current (Y2000) Atmosphere 4.4.4 Model Simulations of Perturbed and Y2100 Atmospheres 4.4.5 Atmospheric Composition for the IPCC Scenarios to 2100 4.4.6 Gaps in These Projections-the Need for Coupled Models 4.4.7 Sensitivity Analysis for Individual Sectors 4.5 Open Questions 4.5.1 Chemical Processes Important on the Global Scale 4.5.1.1 Missing chemistry, representation of small scales, and changing emission patterns 4.5.1.2 Aerosol interactions with tropospheric O 3 and OH 4.5.1.3 Stratosphere-troposphere coupling 4.5.1.4 Uncertainties in the tropospheric O 3 budget 4.5.2 Impacts of Physical Climate Change on Atmospheric Chemistry 4.5.3 Feedbacks through Natural Emissions 4.6 Overall Impact of Global Atmospheric Chemistry Change References
The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the go... more The atmospheric methane burden is increasing rapidly, contrary to pathways compatible with the goals of the 2015 United Nations Framework Convention on Climate Change Paris Agreement. Urgent action is required to bring methane back to a pathway more in line with the Paris goals. Emission reduction from “tractable” (easier to mitigate) anthropogenic sources such as the fossil fuel industries and landfills is being much facilitated by technical advances in the past decade, which have radically improved our ability to locate, identify, quantify, and reduce emissions. Measures to reduce emissions from “intractable” (harder to mitigate) anthropogenic sources such as agriculture and biomass burning have received less attention and are also becoming more feasible, including removal from elevated‐methane ambient air near to sources. The wider effort to use microbiological and dietary intervention to reduce emissions from cattle (and humans) is not addressed in detail in this essentially geo...
Given the number of recent papers that have proposed quite different explanations for the post-20... more Given the number of recent papers that have proposed quite different explanations for the post-2006 rise in atmospheric CH4, it is clear that there are still some major systemic uncertainties in our understanding of the CH4 source – sink budget. While the increasing amount of isotopic (δ CH4) data should help to resolve these uncertainties, this has to deal with a limited understanding of removal by Cl with its very large kinetic isotope effect (KIE), and so a significant effect on δCH4 even though most of CH4 removal is by OH.
Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), ... more Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), 2016 (7.0 ± 0.7 ppb/year), and 2017 (7.7 ± 0.7 ppb/year), at rates not observed since the 1980s. The increase in the methane burden began in 2007, with the mean global mole fraction in remote surface background air rising from about 1,775 ppb in 2006 to 1,850 ppb in 2017. Simultaneously the 13 C/ 12 C isotopic ratio (expressed as δ 13 C CH4) has shifted, has shifted, now trending negative for more than a decade. The causes of methane's recent mole fraction increase are therefore either a change in the relative proportions (and totals) of emissions from biogenic and thermogenic and pyrogenic sources, especially in the tropics and subtropics, or a decline in the atmospheric sink of methane, or both. Unfortunately, with limited measurement data sets, it is not currently possible to be more definitive. The climate warming impact of the observed methane increase over the past decade, if continued at >5 ppb/year in the coming decades, is sufficient to challenge the Paris Agreement, which requires sharp cuts in the atmospheric methane burden. However, anthropogenic methane emissions are relatively very large and thus offer attractive targets for rapid reduction, which are essential if the Paris Agreement aims are to be attained. Plain Language Summary The rise in atmospheric methane (CH 4), which began in 2007, accelerated in the past 4 years. The growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the carbon isotope ratio of the methane. The causes of the rise are not fully understood, and may include increased emissions and perhaps a decline in the destruction of methane in the air. Methane's increase since 2007 was not expected in future greenhouse gas scenarios compliant with the targets of the Paris Agreement, and if the increase continues at the same rates it may become very difficult to meet the Paris goals. There is now urgent need to reduce methane emissions, especially from the fossil fuel industry.
Future changes in New Zealand’s climate are expected to be less than in many other countries, and... more Future changes in New Zealand’s climate are expected to be less than in many other countries, and New Zealand has well established governance structures for dealing with environmental risks. While this might imply that adaptation would be straightforward, extensive public and private investments, as well as many traditional Māori assets and cultural values, are in areas increasingly at risk of flooding and sea level rise. In order to consider the country’s adaptive capacity in more detail, we have used an empirical research approach, working with government practitioners at three levels and with Māori communities.
Very different perceptions of risk, and structural inertia in planning processes have emerged as key issues for implementing adaptation responses. In particular, the use of static frameworks biases responses towards retrospective, rather than anticipatory analysis. Ongoing socioeconomic changes in New Zealand also raise the risk of structural effects caused by climate change impacts becoming unevenly distributed across society. Our analysis indicates that a national and regional strategic approach, centred on a dynamic view of climate risk, is necessary for effective decisions at the local government and community level. In addition, effective adaptation requires better identification of barriers and opportunities for addressing changing risk, together with more effective and continuous social engagement.
Since 1986 the Atmospheric Environment Service (AES) of Environment Canada has operated an atmosp... more Since 1986 the Atmospheric Environment Service (AES) of Environment Canada has operated an atmospheric chemistry program at Station Alert, which is located at 82°N on the northern tip of Ellesmere Island.The program provides a detailed record of atmospheric change in the high Arctic that is crucial to both regional and global issues. Plans to reduce the Canadian government's deficit now require Environment Canada to make budgetary cuts and are prompting reevaluation of this and other programs. In light of these circumstances, we would like to take the opportunity to consider the importance of Alert to international atmospheric science.
Lenny Bernstein, Peter Bosch, Osvaldo Canziani, Zhenlin Chen, Renate Christ, Ogunlade Davidson, W... more Lenny Bernstein, Peter Bosch, Osvaldo Canziani, Zhenlin Chen, Renate Christ, Ogunlade Davidson, William Hare, Saleemul Huq, David Karoly, Vladimir Kattsov, Zbigniew Kundzewicz, Jian Liu, Ulrike Lohmann, Martin Manning, Taroh Matsuno, Bettina Menne, Bert Metz, Monirul Mirza, Neville Nicholls, Leonard Nurse, Rajendra Pachauri, Jean Palutikof, Martin Parry, Dahe Qin, Nijavalli Ravindranath, Andy Reisinger, Jiawen Ren, Keywan Riahi, Cynthia Rosenzweig, Matilde Rusticucci, Stephen Schneider, Youba Sokona, Susan Solomon, Peter Stott, Ronald Stouffer, Taishi Sugiyama, Rob Swart, Dennis Tirpak, Coleen Vogel, Gary Yohe
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Papers by Martin Manning
Very different perceptions of risk, and structural inertia in planning processes have emerged as key issues for implementing adaptation responses. In particular, the use of static frameworks biases responses towards retrospective, rather than anticipatory analysis. Ongoing socioeconomic changes in New Zealand also raise the risk of structural effects caused by climate change impacts becoming unevenly distributed across society. Our analysis indicates that a national and regional strategic approach, centred on a dynamic view of climate risk, is necessary for effective decisions at the local government and community level. In addition, effective adaptation requires better identification of barriers and opportunities for addressing changing risk, together with more effective and continuous social engagement.
Very different perceptions of risk, and structural inertia in planning processes have emerged as key issues for implementing adaptation responses. In particular, the use of static frameworks biases responses towards retrospective, rather than anticipatory analysis. Ongoing socioeconomic changes in New Zealand also raise the risk of structural effects caused by climate change impacts becoming unevenly distributed across society. Our analysis indicates that a national and regional strategic approach, centred on a dynamic view of climate risk, is necessary for effective decisions at the local government and community level. In addition, effective adaptation requires better identification of barriers and opportunities for addressing changing risk, together with more effective and continuous social engagement.