I. INTRODUCTION
Net Zero Targets are at the heart of the fight against global warming and climate change. During the past few years, they have been widely mentioned in an increasing number of documents, from countries' Nationally Determined Contributions (NDCs) to companies climate strategies and investors sustainable investments. Indeed, the number of Net Zero commitments from governments and businesses has doubled during the year 2020 [1]. Morevoer, "Net Zero forms a major theme of this year’s pivotal UN climate summit in Glasgow" [2]. The Net-Zero evolution figure exposed in the gallery below explicitly illustrate the year-on-year increase of Net Zero pledges around the world, with the main method being embedding Net Zero targets through policy documents such as the NDCs. As defined by the UNFCCC, "Nationally determined contributions (NDCs) are at the heart of the Paris Agreements and the achievement of these long-term goals. NDCs embody efforts by each country to reduce national emissions and adapt to the impacts of climate change. The Paris Agreements (Article 4, paragraph 2) require each Party to prepare, communicate and maintain successive nationally determined contributions (NDCs) that it intends to achieve. Parties shall pursue domestic mitigation measures, with the aim of achieving the objectives of such contributions" [3].
II. NET ZERO: A DEFINITION
However, what are Net Zero pledges and what do they imply ? As stated by Net Zero Climate, one of the main Net Zero tracking platform which, "informed by leading climate researchers, brings together principles and policies, practical tools, and progress tracking to help businesses and policymakers achieve that goal" [5], "Net Zero refers to a state in which the greenhouse gases going into the atmosphere are balanced by removal out of the atmosphere" [5]. Simply put, for each ton of anthropogenic CO2-equivalent emitted by a party, the latter must ensure the removal/sequestration of an equivalent amount of GHG Emissions. Net Zero Pledges are based on the upstream scientific consensus that global anthropogenic GHG Emissions "need to fall by about 45 percent from 2010 levels by 2030, reaching net zero around 2050" [5]. Net Zero Commitments all abide by the same 4 general official criteria, defined under the UNFCCC-backed initiative "Road to Net Zero Campaign" [6]. Firstly, writing down the pledge per se. It involves 3 actions: Defining the final target year, defining the interim target year, and abiding by the condition of an exhaustive coverage, i.e. all 3 scopes of emissions as defined by the GHG Protocol. The scope categories are as follow: "Scope 1: All direct GHG emissions. Scope 2: Indirect GHG emissions from consumption of purchased electricity, heat or steam. Scope 3: Other indirect emissions, such as the extraction and production of purchased materials and fuels, transport-related activities in vehicles not owned or controlled by the reporting entity, electricity-related activities (e.g. T&D losses) not covered in Scope 2, outsourced activities, waste disposal, etc." [7]. Secondly, the planning phase. This criterion covers the time scale definition as well as the sinks, carbon crediting scheme or any neutralization methodology used for a transition towards permanent removals of GHG Emissions. This criterion is directly concerned by the current negotiations around Article 6 of the Paris Agreement on international carbon markets. For a clear synthesis on article 6 and why it matters, see "What You Need to Know About Article 6 of the Paris Agreement" from the World Ressources Institute [8]. Thirdly, proceed through actual policy design and direct, tangible actions, towards mitigation and adaptation measures. Mitigation measures refer to the GHG Emissions abatement measures per se, while adaptation measures refer to the various policies which aim at increasing infrastructure resilience against natural hazards induced by climate change. For further development on mitigation and adaptation measures, see "What is the difference between adaptation and mitigation?" from the European Environment Agency [9]. Fourthly, providing "immediate contributions to the preservation and restoration of natural sinks [6]. Lastly, the last criterion involve publishing and promoting the various achieved milestones all the way until Net Zero.
III. MAGNITUDE AND STRUCTURE OF NZ COVERAGE
However, Net Zero Pledges, as of Q1 2021, are not homogeneous in their constituting features. The "Net Zero global coverage" figure and depict the current state of the Worldwide Net Zero Scene, as well as its geographical distribution. There were, as of Q1 2021, between 44 and 59 countries which have already set Net Zero targets, covering between 54prct (Figure 2.3.c.) and 61prct (Figure 2.3.b.) of worldwide GHG Emissions. The disparity between numbers is due to the fact that IEA defined the EU as a Net Zero Region as a whole, whereas ClimateWatch include the Net Zero targets of each EU countries.. There is however no overlapping between geographical, sectorial and GHG coverage. Some GHG and sectors might be excluded from Net Zero targets on a case-by-case logic. For example, the IEA "Net Zero by 2050" [4] report state that "New Zealand’s net zero pledge covers all GHGs except biogenic methane, which has a separate reduction target" [4], or that "the Netherlands aims to achieve net‐zero GHG emissions only in its electricity sector" [4]. Regarding the interaction between the status: "In law = a net zero pledge has been approved by parliament and is legally binding. Proposed = a net zero pledge has been proposed to parliament to be voted into law. In policy document = a net zero pledge has been proposed but does not have legally binding status" [4] and GHG coverage of Net Zero targets, legally binding targets represent 1,9prct of global GHG Emissions, targets in policy document represent 18,8prct of global GHG Emissions, and targets in political pledge represent 33,3prct of global GHG Emissions [10]. Additionally and to further understand the magnitude of the existing Net Zero targets, covered areas and sectors represent 68prct of worldwide GDP, and 56prct of world population.
IV. NET ZERO AND DECARBONISATION POLICIES
Lastly, to fully understand the Net Zero environment and how it interact with decarbonisation policies such as carbon price or the CBAM, we must break it down by industry, and understand how carbon pricing is essential to bring key decarbonization pillars together. The "global net zero pathway" figure below describes the key milestones to go through in order to reach Net Zero by 2050, while simultaneously giving the magnitude and abatement trends for key industries. As illustrated by the 2021 "no new coal plants" milestone, Coal-phase-out and Oil-phase-out are the starting point of the "Road to Net Zero". This is corroborated by the UNFCCC conclusion after COP23 in 2017, stating that "Phasing-out the production and use of fossil fuels is essential to meeting the Paris Agreement’s 1.5-2°C temperature limits" [11]. This phase out process is undertaken by stopping field exploration and decreasing investments in hydrocarbons: no new unabated coal plants and now new oil and fields gas approved for development starting 2021; no new sales of fossil fuels boilers starting 2025, etc. Furthermore, a study of sectoral pathways to net-zero emissions by 2050 break down the key trends and milestone for reaching net-zero in fuel supply, electricity, industry, transport, and buildings. The same figure offers some examples of said milestones in the concerned sectors. In that perspective, economic features such as a robust carbon price are needed in order to rally those trends in optimal conditions towards net-zero by 2050: As argued in the IEA Report, "adopting a carbon price and then sufficiently increasing the price over time – through carbon taxes}or emissions trading systems for larger manufacturers – may be the simplest way to achieve that objective" [4], i.e. to facilitate the deployment of low-emissions technologies in concerned sectors.
BIBLIOGRAPHY
[1] UNFCCC.(2020). Commitments to Net Zero Double in Less Than a Year.
[2] Black, R., Cullen, C., Fay, B., Hale, T., Lang, J., Mahmood, S., Smith, S. (2021). Taking Stock:
A global assessment of net zero targets. Energy and Climate Intelligence Unit.
[3] UNFCCC.(n.d.). Nationally Determined Contributions (NDCs)
[4] IEA.(2021). Net Zero by 2050. IEA: Paris
[5] Net Zero Climate.(n.d.). What is Net Zero.
https://netzeroclimate.org/.
[6] Net Zero Climate.(n.d.). Principles for making a Net Zero commitment.
https://netzeroclimate.org/policies-for-net-zero/net-zero-principles/
[7] Greenhouse Gas Protocol.(n.d.). Calculation tools.
https://ghgprotocol.org/calculationg-tools-faq
[8] World Resources Institute.(2019). What You Need to Know About Article 6 of the Paris Agreement.
https://www.wri.org/insights/what-you-need-know-about-article-6-paris-agreement
[9] European Environment Agency.(n.d.). What is the difference between adaptation and mitigation?
https://www.eea.europa.eu/help/faq/what-is-the-difference-between
[10] Climate Watch.(n.d.). Net Zero tracker.
https://www.climatewatchdata.org/net-zero-tracker
[11] Gerasimchuk, I., Merrill, L., Bridle, R., Gass, P., Sanchez, L., Kitson, L., Wooders, P.} (2018). Fossil Fuel Phase-Out and a just transition: Learning from stories of coal phase-outs. International Institute for Sustainable Development.
