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IPCC Report and International Law on Climate Change

- Chhaya Bhardwaj

The Inter-governmental Panel on Climate Change (IPCC) released the Synthesis Report of the IPCC Sixth Assessment Report, raising concerns about the increasing Greenhouse Gas (GHG) emissions globally. The IPCC was created under the UN General Assembly Resolution 43/53 in 1988. Since then, IPCC has been considered the politically and scientifically consented authority on climate change science. In addition to preparing six assessment reports so far, the Panel has responded to the requests from the United Nations Framework Convention on Climate Change (UNFCCC) and other governmental and international organizations on specific climate change issues, feeding directly into international climate policymaking. IPCC's creation and overall work have led to the progressive development of international law on climate change. Through this article, the author aims of underscore IPCC reports’ growing significance to the progressive development of international law on climate change, especially within the international judicial forums.

IPCC publishes its scientific assessments at a six- or seven-year cycle. The Fifth Assessment Report cycle was completed in 2014, and the sixth assessment cycle completes with the sixth assessment. The Fifth Assessment Report was foundational to the Paris Agreement. The IPCC report is a symbolic representation of the state-of-the-art existing, rapidly evolving science of climate change. Apart from its role in the treaty-making and negotiation processes during and after the climate change treaty-making, the IPCC report is central to compliance mechanisms in international climate change law. The IPCC guides and supports countries to prepare and continuously improve their national GHG inventories. Under Article 13 of the Paris Agreement, the states must prepare a national emissions inventory report using IPCC's good practices methodologies. The IPCC has also developed its Task Group for its future work in light of the Global Stocktake.

These are non-judicial compliance mechanisms, requiring states to observe the conditions of climate change treaties. E.g. in the Case of the Non-compliance Procedure of Bulgaria under the Kyoto Protocol in 2010, the IPCC's good practices were followed by Bulgaria when managing its GHG inventory. The decision was that "Bulgaria's institutional arrangements and arrangements for technical competence of staff within the national system involved in the inventory development process were insufficient to enable the adequate planning, preparation and management of the Party's annual submission following the guidelines for national systems". This decision concerning the compliance mechanism under the treaty referred extensively to the IPCC reports and guidance. With the emergence and development of compliance mechanisms under the Paris Agreement, and the countdown to the first global stocktake under the Paris Agreement, the role of IPCC becomes crucial. In the treaty-making procedures, the IPCC report is the political and scientific basis for consensus. The compliance mechanism guides the States on issues of science and good practices, and the compliance of States is tested to determine whether the States' actions follow the IPCC guidance.

The IPCC report has served as one of the fundamental scientific pieces of evidence against states before judicial and quasi-judicial decisions before international forums. The Human Rights Committee has used the IPCC report twice to decide on issues at the crossroads of the right to life and climate change. In the Torres Strait Islanders Case, the author and the Human Rights Committee relied on the scientific assertions of the IPCC when discussing the adverse effects of climate change. The Committee decided that Australia impaired the right to culture and right to privacy and family by failing to take adequate adaptation and mitigation measures in Australia. In Ioanne Teitiota v. New Zealand, the Committee took note of the IPCC's fifth assessment report while analyzing the impacts of climate change and sea-level rise on island nations and people living therein. The Committee also invited experts to testify before the court, give scientific evidence on issues, and corroborate the science. Based on the evidence, the Committee in Teitiota decided that New Zealand did not impair the "right to life" and, more generally, did not violate international law concerning human rights. Similarly, before the Inter-American Court of Human Rights, the Request for an Advisory Opinion on Climate Emergency and Human Rights refers to the IPCC report as a scientific and political consensus on climate change.

The IPCC reports may also be used as evidence before different international judicial forums on issues of responsibility for climate change. The UN General Assembly is seeking ICJ's opinion- which also refers to the IPCC reports, with the hope for "bolder" climate action; the question of historical, current and future GHG emissions will be central to addressing legal questions on who should be responsible. The burden of proof to establish the existence of facts lies on the party who asserts those facts (Pulp Mills on the River Uruguay (Arg. v. Urm.), Judgment, 2010 ICJ 14, ¶ 162). It means the general discourse would be that the states seeking State responsibility for climate change will have to adduce evidence to attribute climate change, GHG emissions and adverse effects of climate change as an internationally wrongful act before the ICJ. Whether emitting GHG to cause climate change or causing the adverse effects of climate change is an internationally wrongful act or not is also likely to be discussed and has many layers to it. Overall, the States requesting the advisory opinion or seeking responsibility of a specific state will carry the responsibility to provide evidence for it. One of the potential arguments to shift the burden of proof on states denying climate change-related responsibility could arise from applying the precautionary principle. In his dissenting opinion in Nuclear Tests ((NZ v. Fr.), 1995 ICJ 288, 320 September 22), Weeramantry, J., holds to apply principles of environmental law to shift the burden on states engaged in alleged environmentally degrading activities and to prove that those activities are safe and environmentally friendly. While this is an advisory opinion before the ICJ, rules concerning applying the precautionary principle to shift the burden of proof will align with the WTO's application of the precautionary approach when looking at scientific evidence, especially in the Beef Hormones Case. The ICJ does not have a rule of evidence it is bound to follow and can apply its discretion, especially in science-intensive cases.

The IPCC report can be used for its probative or circumstantial value as scientific evidence for historical, current and future emissions to establish responsibility for emissions under international law. On the question of historical responsibility, however, scholars have always raised concerns about pinning it on specific countries because of a lack of accurate knowledge about historical emissions, even after the release of the sixth assessment report. The report states that "historical emissions between 1850 and 2019 constitute a large share of total carbon budgets for these global warming levels". It further states that "the largest contributor to historical human-induced warming is CO2, with historical cumulative CO2 emissions from 1850 to 2019 being 2400 ± 240 GtCO," Out of these, around 58 per cent occurred between 1850 to 1989 and 42 per cent occurred between 1990 and 2019. This historical and scientific data is foundational when answering who is historically responsible for carbon emissions. The period between 1882 to 1960 is also commonly known as The (British) Colonial Era, where a large part of the world was under the British Rule. Therefore, activities within the British Colonies, that cause carbon emissions, can be attributed to the British Empire. This is also the time period when the world witnessed World War I and II, and wars contributed greatly to climate change. The major participants of these World Wars were largely the developed countries or the countries from Global North and perhaps, the independent participating countries can be held responsible fro emissions due to the war. The colonies like India- A British Colony or Philippines- An American Colony, can be exempted from responsibility, even if they participated in the war, because they were neither independent, nor a major participating country in these wars. When developed deeper, the issue of historical emissions also seems like a very complex issue in the context of pointing a specific responsibility for climate change.

The World Resources Institute prepared an observation into carbon emissions for the top ten emitters from 1850 to 2016. The United States, United Kingdom, and Germany won the top positions until 2016 when China became the top emitter. Historically, the rich colonial countries win the race of top emitters. The chart displays a point where India is among the top five emitters between 1850-1947. It was the era of British colonial rule in India, so it may only be reasonable to state that the colonizer should take responsibility for these emissions. Notably, most sovereign states known today were created post-1945 and fall within the group of low-carbon emitting countries. There were various circumstances and complex socio-political situations for States during the 1850-1980s. Therefore, the courts are likely to consider varied direct and indirect evidence to establish a specific fact. It implies that the IPCC report may not lead to a firm conclusion sufficient to attribute responsibility for historical emissions, even if it establishes certain other facts about GHG emissions.

The IPCC report by itself may not establish a prima facie responsibility (The Corfu Channel Case (merits) Judgement of April 9, 1949, page 18) for historical emissions. Therefore, it's likely to be "circumstantial evidence". The ICJ may endorse circumstantial evidence in certain cases. In the Corfu Channel Case, it stated that in certain cases, "a more liberal recourse to inferences of fact and circumstantial evidence" may be allowed, especially "when it is based on a series of facts linked together and leading logically to a single conclusion." (page 18).

The IPCC report may be considered circumstantial evidence to establish state responsibility for current and future GHG emissions. Naomi Oreskes asserts that states emitting GHGs today should rationally be responsible for causing climate change in the present. She also says these countries are likely to cause climate change in future too. The present-day GHG emissions are easy to attribute to a particular state, with the IPCC scientific reports as an evidentiary basis. For countries like the United States, the United Kingdom and several countries from the European Union, GHG emissions are a matter of lifestyle debate due to their carbon-intensive lifestyle. For countries like China and India, GHG emissions are a developmental issue. It implies, at least in the case of India, that there will be first-generation owners of the most worldly things like cars, vehicles or refrigerators. However, for countries like Tuvalu and Kiribati, one of the lowest GHG emitters in the world but the most vulnerable to climate change, GHG emissions are a matter of survival. Small island nations like Tuvalu and Kiribati are likely to never compete with the first two groups of countries and are highly likely to go through the fight to protect their nation from inundation by the sea. If these small island nations are the real victims of climate change and economic development worldwide, then seeing the world from a victim-centred approach might lead to "bolder" climate action.

The IPCC report also discusses how states should be differentiated based on their geographic location, which means how and why states in different geographies are experiencing climate change differently. This issue of geographies became more relevant as the UN resolution submitted a request for an advisory opinion before the ICJ published the final list of questions. The question concerns the legal consequences under the obligations for States where acts or omissions of states have caused significant harm to the climate system of states which are injured or particularly vulnerable to climate change due to their geographical circumstances.

In addition to issues concerning state responsibility, the IPCC report discusses other forms of individual responsibility for non-state actors. The report states that "Individuals with high socio-economic status contribute disproportionately to emissions and have the highest potential for emissions reductions, e.g., as citizens, investors, consumers, role models, and professionals." These examples may very well include the high-income BIG-OIL corporations because the report states that "by 2019, the largest growth in absolute emissions occurred in CO2 from fossil fuels and industry followed by CH4", very specifically pointing towards fossil fuel industry and corporations. These scientific assertions could also establish responsibility for current or ongoing emissions.

While the advisory opinions and first stocktake under the Paris Agreement are pending, the solutions provided within the report will be instrumental. The report also talks about solutions which do not need an advisory opinion for implementation. These include building mitigation infrastructure in nations; switching to 'Electric vehicles powered by low-emissions electricity offers the largest decarbonization potential for land-based transport, on a life cycle basis (high confidence)'; 'the conservation, improved management, and restoration of forests and other ecosystems (coastal wetlands, peatlands, savannas and grasslands), with reduced deforestation in tropical regions' and increased financial flows to the most vulnerable countries.

The challenge to IPCC in this age of information, disinformation, misinformation and alternative information has already surfaced. Recently, "The World Climate Declaration" has surfaced, stating that "there is no climate emergency". Around 1200 scientists claim that there is no climate emergency through this Declaration. However, this Declaration is believed to be funded by the Fossil fuel industry, presenting an alternative science to the well-established climate change science. This phenomenon may be compared to the 2006 Big Tabacco Lawsuit, where the tobacco industry presented extensive evidence denying the deadly effects of cigarettes and smoking. As a scholar of climate change, I will remain optimistic that the world will see through the well-established science and not science developed by climate change deniers or entities that make money by driving climate change. However, I will conclude with a question- "how easy or difficult would it have been for the small islands developing countries to claim that climate change is adversely affecting them if IPCC was not created?

Conclusively, the emerging role of the IPCC reports to assert politically and scientifically accepted evidences of climate change is important. The reports are inevitable to a progressive development of international law and national law on climate change. With the pendency of various advisory opinions before the international courts and tribunals, the role of IPCC is also likely to expand. This will become clearer, as we progress with the pending advisory opinions. However, as an optimistic climate law scholar, I would like to see climate science integrating more at international and national legal and policy levels.


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