Low Carbon Pulse Edition 24
18 August 2021
18 August 2021
Welcome to Edition 24 of Low Carbon Pulse. This edition reports on the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report – Climate Change 2021, The Physical Science Basis (2021 Report).
This Edition 24, intended as a high-level summary of the key findings in the 2021 Report, is divided under the following headings: 1. Context of the 2021 Report; 2. Conclusions from the 2021 Report; 3. What organisations need to know; 4 The key findings of the 2021 Report (including specifically under its five models); and 5. Description of the subject matter of Twelve Chapters in the 2021 Report.
A PDF version of this article is available for download below.
The 2021 Report is the first fully fledged report from the IPCC since its 2013 Report (the Fifth Assessment Report), and the first report since the 2018-2019 Special Reports.
The findings outlined in the 2013 Report informed the provisions included in the Paris Climate Agreement (Paris Agreement) which entered into force on November 4, 2016. The Paris Agreement now has 195 signatories; each was consulted on the 2021 Report. The 2021 Report is subject to further work from which a Synthesis Reports will emerge.
The Paris Agreement recognises the science of the 2013 Report: the imperative of keeping the increase in "global average temperature to well below 2OC above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5OC above pre-industrial levels".
For these purposes, it was agreed "to reach global peaking of greenhouse gas emissions as soon as possible", "to undertake rapid reductions thereafter … so as to achieve a balance between anthropogenic emissions by sources (NZE) and removals (GHG Removal) … in the second half of this century…", with each Party to set a nationally determined contribution (NDC) to the reduction in greenhouse gas emissions (GHG), with a stock-take to be undertaken periodically; the first undertaken in 2018, the second to be undertaken in 2023.
The purpose of the 2021 Report is to provide a basis for informed progress at COP-26, and to allow countries to adjust their NDCs in the lead-up to the 2023 stocktake, or before (ideally before COP-26).
developing a net zero strategic action plan, and to adjust that plan to respond to on-going assessment and oversight (NZE Plan);
demonstrating that the NZE Plan is modelled as achievable and is fully-costed, and includes the impact on earnings, and distributions, from the implementation of the NZE Plan;
establishing data capture and measurement systems that capture all relevant data to allow effective monitoring and reporting on compliance with the NZE Plan anticipating that climate-related disclosure obligations will tighten overtime;
appointing executives with responsibility for the implementation of the NZE Plan, with board approval and overnight of its implementation; and
engaging actively with investors and other key stakeholders on an on-going basis and expecting investors to require consultation in respect of, and, over time, approval of, the NZE Plan.
Physical climate change risks are now widely understood by the international business community as financial risks that represent a critical business challenge as well as opportunity: the long-term connection between the health of the planet and the health of the world economy is accepted. The Swiss Re Climate Institute Report from April 2021 shows this clearly.
At the recent June 2021 meeting of the Group of Seven, comprising Canada, France, Germany, Italy, Japan, UK and US (G7), there was agreement on the need to require compulsory disclosure of climate-related financial risks.
It is clear that the TCFD understands that reporting on an activity requires an assessment of that activity, and that reporting on NZE means that NZE is an objective: the progress towards, and ultimately the achievement of, NZE across each of Scope 1, 2 and 3 emissions, is being measured.
All corporations require financial services, including from debt and equity markets, financial institutions providing working capital facilities, and insurers insuring the risks arising from those activities. Disclosure on progress to NZE is a key tool: even before disclosure is made compulsory, many key participants in the financial services industry want to understand how corporations are progressing to NZE, and how they plan to achieve NZE. The TCFD has made assessment, monitoring, analysis and disclosure a positive for organisations: key to risk assessment, capital allocation and strategic planning.
Access to debt and equity from the financial services industry has ceased in respect of certain activities in some jurisdictions, and the terms on which financial services are provided are increasingly differing depending on progress to, and achievement of, NZE. As lawyers, Ashurst people see this on a daily basis.
Stated another way, the root cause of climate change is the increase in temperature caused by increased mass of GHGs in the climate system, increasing the concentration of GHGs in the climate system, principally CO2, CH4 and N2O.
|CONCENTRATIONS OF WELL MIXED GHG|
|2019||410 ppm||1866 ppb||322 ppb|
|JUNE 2020||416.60 ppm||1876 ppb||332.7 ppb|
|JUNE 2021||418.54 ppm||1891 ppb||334.1 ppb|
The CO2 concentrations are higher than at any time in the last two million years, and concentrations of CH4 and N2O are higher than at any time in at least 800,000 years.
CO2-e (carbon dioxide equivalent) recognises that different GHGs have different global warming effects, with the use of CO2-e allowing a like-for-like comparison taking account of potency and time retained in the climate system. What is clear however is that CO2 is the GHG on which GHG reduction and GHG Removal initiatives need to concentrate because globally, by mass, it is, by far, the most emitted GHG. At the same time, there needs to be a near to medium term concentration on the reduction of CH4.
reduce GHG emissions through decarbonisation of activities that give rise to GHG emissions; and
increase the negative GHG emission initiatives (NGHGEIs) for the purpose of removing CO2 from the atmosphere on an absolute basis, and, long term, to limit continued emission of GHGs using carbon credits / permits to off-set those continued GHG emissions.
The 2021 Report considers the impact of increased concentrations of GHG emissions on all aspects of the climate system, focusing on the atmosphere (air and surface temperatures), biosphere (parts of earth where life exists), cryosphere (parts of the world that are frozen) and oceans. Each of the Twelve Chapters considers these impacts.
It is necessary to emphasise that the impact of increased concentrations on GHG emissions is not the same globally, or by GHG.
The 2021 Report makes it clear that climate change can result in increased GHG emissions, which in turn results in climate change: "climate-change-on-climate-change", as a result of additional biogeochemical feedbacks in the climate system, which may amplify or attenuate the impact of increasing temperature on the climate system.
The length of this Edition 24 does not permit consideration of each climate impact, but the following climate impact findings are key:
Figure SPM.3: Synthesis of assessed observed and attributable regional changes from page SPM-12 of the SPM show the findings as to climate system change on a regional basis.
In addition to the findings, the balance with which the findings are expressed in the 2021 Report is telling, and provides the reader with considerable confidence of the analysis of the underlying data, and the calibration of the assessment of it. This may be regarded as contrasting with some of the reporting of the findings in the 2021 Report: it is best to go to the findings itself, rather than the reporting of any findings.
The 2021 Report has five SSP models (each allowing for solar activity and background forcing from volcanic activity), with each SSP model making the following assumptions:
SSP refers to Shared Socio-Economic Pathway, i.e. how society, demographics and economics might change this century.
The projected outcome for each SSP model is represented graphically in the SPM as follows:
Going to the root cause of climate change, reducing GHG emissions slows the rate of increase and stabilises the GHG emissions in the climate system, there is then the need to peak and reduce and remove GHG.
Peaking and reducing: If the world passes peak GHG emissions (and it is noted that it may not), with continued reductions after the peak to a point at which the mass of GHG emissions arising is less than the mass of GHG emissions removed, there will be a decline in GHG emissions, but there will be a lag. The length of the lag will depend on the profile of GHG emissions leading up to peaking and the rate of GHG emission reductions and GHG Removal. In the language of the 2021 Report: the accumulation of GHGs in the climate system is determined by the balance between anthropogenic emissions, anthropogenic removals and physical-biogeochemical source and sink dynamics on land and in the ocean.
CDR: afforestation, soil carbon sequestration, bioenergy with carbon capture and storage (BECCS), wet land restoration, ocean fertilisation, ocean alkalinisation, enhanced terrestrial weathering and direct air capture and storage (DACS) are all means of CO2 removal. For these purposes, author has chosen not to include SRM.
Every organisation undertakes activities that give rise to GHG emissions, Scopes 1, 2 and 3. Every organisation can decarbonise those activities or remove GHG emissions, or both. As noted above, the starting point for any organisation seeking to reduce GHG emissions arising from those activities is to identify its GHG emissions profile: which activities give rise to GHG emissions, and what is their mass?
Detailed below is a description of what each of the Twelve Chapters covers (bold and italics indicating Sections of interest to the author):
1. Chapter 1 (Introduction to 2021 Report): Section 1.1: Report and Chapter Overview; Section 1.2: Where are we now? How We Got here; Section 1.4: Foundations and Concepts; Section 1.5: Major Developments since ARS 5; Section 1.6: Dimensions of Integration; and Section 1.7: Final Remarks;
2. Chapter 2 (Changing State of the Climate System): Section 2.1: Introduction; Section 2.2: Changes in Climate Drivers; Section 2.3: Changes in Large Scale Climate: 2.3.1: Atmosphere and Surface, 2.3.2: Cryosphere; 2.3.3: Oceans, and 2.3.4: Biosphere and 2.3.5: Synthesis of evidence for past changes; Section 2.4: Changes in Modes of Variability; and Section 2.5: Final Remarks;
3. Chapter 3 (Human Influence on the Climate System): Section 3.1: Scope and Overview; Section: 3.2: Methods; Section: 3.3 Atmosphere and Surfaces; Section 3.4: Cryosphere; Section 3.5: Ocean; Section 3.6: Biosphere; Section 3.7: Modes of Variability; and Section 3.8: Synthesis across Earth System Components (of Human Influences on Atmosphere and Surfaces, Cryosphere, Ocean and Biosphere);
4. Chapter 4 (Future Global Climate: scenario-based projections and near term information): Section 4.1 and 4.2: Overview and Methodology; Section 4.3: Selected key indicators over the 21st Century; Section 4.4: Near Term; Section 4.5: Mid-to-long term; Section 4.6: Policy Implications; Section 4.7: Beyond 2100; and Section 4.8; High Warming Storylines;
5. Chapter 5 (Global Carbon and other Biogeochemical Cycles and Feedbacks): Section 5.1: Introduction and Palaeo Context; Section 5.2: Historical Trends, Variability and Budgets of CO2 (Section 5.2.1), CH4 (Section 5.2.2) and N2O (Section 5.2.3), Relative Importance of CO2, CH4 and N2O (Section 5.2.4); Section 5.3: Ocean Acidification and Deoxygenation; Section 5.4: Biogeochemical Feedbacks on Climate Change; Section 5.5: Remaining Carbon Budgets; Section 5.6: Biogeochemical Implications of CO2 Removal and Solar Radiation Modification, and Section 5.7: Perspectives on the Limits of the Assessment;
6. Chapter 6 (Short-lived climate forcers): Section 6.1: Importance of SLCFs for Climate and Air Quality; Section 6.2: SLCF emissions; Section 6.3: SLCF atmospheric abundance; Section 6.4: SLCF radiative forcing, climate effects and feedbacks; Section 6.5: Implications of changing climate on Air Quality; Section: 6.6: Air Quality and Climate Response to SLCF mitigation; Section 6.7: Future projections of atmospheric composition and climate response in SSP scenarios; and Section 6.8: Perspectives;
7. Chapter 7 (The Earth's energy budge, climate feedbacks, and climate sensitivity): Section 7.1: Introduction, conceptual framework, and advances since AR5 [i.e., 2013 Report]; Section 7.2: Earth's energy budget and its changes through time; Section 7.3: Effective radiative forcing; Section 7.4: Climate feedbacks; Section 7.5: Estimates of ECS and TCR; and Section 7.6: Metrics to evaluate emissions;
8. Chapter 8 (Water Cycle Changes): Section 8.1: Introduction; Section 8.2: Why should we anticipate water cycle changes?; Section 8.3: How is the water cycle changing and why?; Section 8.4: What are the projected water cycle changes?; Section 8.5: What are the limits for projecting water cycle changes? Section 8.6: What is the potential for abrupt change? and Section 8.7: Final remarks;
9. Chapter 9 (Ocean, cryosphere and sea level change): Section 9.1: Introduction; Section 9.2: Oceans; Sections 9.3, 9.4 and 9.5: Cryosphere; and Section 9.6: Sea Level, and Section 9.7: Final Remarks;
10. Chapter 10 (Linking global to regional climate change): Section 10.1: Foundations; Section 10.2: Observations; Section 10.3: Models; Section 10.4: Attribution and emergence; Section 10.5: Context and distillation; Section 10.6: Comprehensive examples; and Section 10.7: Final Remarks;
11. Chapter 11 (Weather and climate extreme events in a changing climate): Section 11.1: Framing; Section 11.2: Data and Methods; Section 11.3: Temperature Extremes; Section 11.4: Heavy precipitation / pluvial floods; Section 11.5: River Floods; Section 11.6: Droughts; Section 11.7: Extreme Storms, including tropical cyclones; Section 11.8: Compound Events; and Section 11.9: Regional information; and
12. Chapter 12 (Climate change information for regional impact and for risk assessment): Section 12.1: Framing; Section 12.2: Methodological Approach; Section 12.3: Climatic impact drivers and affected sectors; Section 12.4: Regional Changes to climatic impact drivers; Section 12.5: Global perspective of changes in climatic impact drivers; Section 12.6: Climatic change information in climate services; and Section 12.7: Final Remarks.
Below is a list of the reports referenced in this edition of Low Carbon Pulse:
|AR6 Climate Change 2021: The Physical Science Basis (2021 Report)|
|Climate Change 2013: The Physical Science Basis (2013 Report)|
|Special Report: Climate Change and Land|
|Special Report: Global Warming of 1.5 oC|
|2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories|
|Special Report on the Ocean and Cryosphere in a Changing Climate|
The author of Low Carbon Pulse is Michael Harrison.