Climate Science and Litigation: It’s Gettin’ Hot in Here

Published on Wednesday, 30 January 2019
Farmers with their cows in Myanmar during a very dry season.

Late last year, the LPR team presented on climate change science at the Asia-Pacific Judicial Conference on Environmental and Climate Change Adjudication in Myanmar. We’re not scientists, why not stick to what we know?

Well, climate change is coming and it’s coming to a court near you. Climate litigation in Asia and the Pacific will grow and it  will increasingly emerge as an issue during environmental and other litigation. Awareness of the science will be important for understanding the nature of cases in your docket and for resolving litigation.

It’s a Wrap: Scientists Actually Agree that Climate Change is Real

Climate change grabs global headlines. The media (and politicians) seem deeply divided on whether it’s real and why it’s happening. You would have read articles affirming that humans have caused climate change. In contrast, other articles deny climate change, often on the basis that scientists have debunked climate change theories. Meanwhile, weather patterns in your local area probably have not changed that much. Sure, we are starting to see more heat waves or more intense storms globally. But, most of us are generally not experiencing the predicted extreme weather variations. Given how divided the media is on the issue, and the somewhat far off impacts, you could easily assume that the scientific community is split on the science. 

But, that’s not the case. Ninety-seven percent of actively publishing climate scientists agree that humans are causing global warming: see Figure 11.  

Figure 1: Studies into scientific agreement on human-caused global warming


Source: J. Cook et al. 2016. See Footnote 1. Illustration: J. Cook.

Climate science isn’t precisely a rookie field. John Tyndall proved the greenhouse effect in the 1850s. He showed that gases like carbon dioxide (CO2) absorb heat and act like a blanket around the Earth, regulating temperatures.  In the 1890s, Svante Arrhenius showed that CO2 produced by factories and machines would increase global temperatures.  

Over the last 40 years in particular, scientists have researched and debated the topic extensively. Technology has improved, enabling greater data accuracy and greater certainty. The scientific community has reached general agreement. Almost 200 worldwide scientific organizations accept that human action causes climate change.  In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change (IPCC) said it is extremely likely—greater than a 95% probability—that global warming since the 1950s has resulted from human activity.  The report cited 9,200 scientific publications and was reviewed by more than 1,000 expert reviewers.  The IPCC’s 195 member governments approved the summary report line by line.  We have no data on the amount of coffee consumed during that read through. 

The world’s countries are actually also in consensus. All countries are party to the United Nations Framework Convention on Climate Change. There are 184 parties to the Paris Agreement.  Both instruments rely on science. They acknowledge that human activities have substantially increased atmospheric concentrations of greenhouse gases (GHGs), contributing to more warming.  

How Can Scientists Know That Earth’s Climate Is Changing? It’s In the Ice.

Data recorded from ice core samples shows that Earth’s climate has cycled between ice ages and warm periods for the last 800,000 years.  During that timeframe, atmospheric CO2 levels went up and down in a consistent range: see Figure 2. CO2 levels varied between roughly 170 to 300 parts per million (ppm). Scientists have researched the reasons for Earth’s temperature fluctuations. They found that GHGs have exerted the greatest control over Earth’s climate for at least 800,000 years. The climate record also robustly shows that CO2 and global temperature move together, as do sea levels: see Figures 2 and 3.  In short, when CO2 goes up, temperature goes up, and sea levels go up. 

Figure 2: 800,000 thousand years of CO2 and temperature against current levels


Source: NOAA (based on data from Jouzel et al. 2007; Lüthi et al. 2008), updated with NOAA CO2 data:

That’s problematic for us all. Human-caused emissions since the industrial revolution have driven large increases in the atmospheric concentration of CO2, methane, and nitrous oxide—all GHGs.  In September 2018, the National Oceanic and Atmospheric Administration (NOAA) measured the average global CO2 levels as 405 ppm, far above the normal range for almost 1 million years.  Emission rates are accelerating too. From 1970 to 2011, CO2 emissions increased by about 90%, with 78% of those emissions coming from fossil fuel combustion and industrial processes.  It’s also important to understand that there is a lag between atmospheric CO2 levels and temperature changes. There are more rises in the pipeline for temperature and sea level unless we reduce CO2 in the air.16

Figure 3: Temperature, CO2, and Sea Level for 420,000 years


Source: J. Hansen. 2018. Climate Change in a Nutshell: The Gathering Storm. New York. p. 25.

What Does Science Say About Global Temperatures? 

We’ve all seen graphs showing increasing global temperatures. But, did you know that current rates of warming are about 10 times faster than previous ice-age-recovery warming?17  Previously—during the past 800,000 years—it took around 5,000 years for the Earth’s temperature to warm by 4ºC–7ºC.18 In contrast, the Earth just warmed 0.8ºC since 1880.19  

Current national climate pledges could limit warming to 3.2ºC by 2100.20  But, the IPCC projects that if we continue with business as usual approaches, atmospheric concentrations of CO2 will likely exceed 1,000 ppm by 2100—more than 3 times the atmospheric CO2 levels for the last 800,000 years—resulting in a 4.8ºC temperature increase since pre-industrial times.21  In October 2018, the IPCC released its special report showing the dire impacts of a 1.5ºC–2ºC temperature increase.22  At a 1.5ºC warming, 75% of the world’s coral reefs will die. Fast action is imperative. The IPCC considers it likely (> 66% probability) that global temperatures will reach 1.5ºC as early as 2030. That’s 11 years away.

What Are Some Litigants Doing with the Science? 

Most cases won’t dispute the scientific consensus on 21st Century climate change.23  Indeed, few cases have focused on climate science in Asia and the Pacific. In South Asia, litigants have focused on their constitutional rights to life and a clean environment to support their claims against government for greater climate action.24  

The Philippines is home to a vanguard human rights inquiry into alleged violations by the world’s carbon majors.25  The Philippine Commission on Human Rights is investigating whether climate change impacts human rights and, if so, whether the carbon majors have responsibility for climate change. Science is central to the inquiry.26 This is a challenging case. There is no legally binding international instrument establishing a human right to an environment that sustains continued life for existing species.27 If the Commission finds for the petitioners, implementing any orders will be challenging. The Commission can recommend appropriate measures to the Philippine Congress.28  But, whether Congress actions those recommendations depends on political will. The true value of the Commission’s findings lies in the potential for it to be a landmark decision. The Commission will release its findings and recommendations in June 2019. 

Climate litigation in the Pacific remains relatively quiet save a few unsuccessful climate migration cases filed by Kiribati and Tuvalu citizens in Australian and New Zealand courts.29 “Migration with dignity” is increasingly seen as an important adaptation tool. But, what does it mean? Dignity means we need to treat people with worth, honor, and esteem. We must involve communities and give them choices and opportunity in resettlement. Consensus-building processes must also enable women, children and youth, people with disabilities, the aged, and indigenous peoples to participate meaningfully. 

Key Takeaways

The science might be settled, but global action and impacts are not. Without radical changes, Asia and the Pacific will emit 48% of the world’s share of CO2 by 2030.30  Asia and the Pacific are extremely vulnerable to climate change impacts.  The window of opportunity is small and our collective future hangs on urgent action. As climate impacts grow, citizens will look to the courts for climate justice.

Climate litigation will not necessarily be that big test case with someone suing the government for action. Challenges to environmental impact assessments or pollution cases can benefit climate action because they indirectly target GHG emissions. Litigation to protect forests and mangroves can boost carbon sequestration or improve resilience to sea level rise. Awareness of local climate change challenges will help judges see when a matter has a climate change dimension. Given how important this topic is, we plan to keep writing about climate change litigation over the course of 2019.

ADB’s Climate Change Litigation Resources

You may have read our earlier updates on our climate change litigation project. In 2018, we researched our book on climate change litigation for Asian and Pacific judges. We also re-thought the book format. We have decided instead to publish a series of working papers, blogs, and articles (like this) on climate change litigation. The information will still be there. But, we wanted to release the information sooner than a book would allow. We will continue to communicate our plans and release updates in 2019.

J. Cook et al. 2016. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environ. Res. Lett. 11 (2016) 048002. The study reviewed papers published between 1991 and 2011. Source: J. Cook et al. 2016. See Footnote 1. Illustration: J. Cook.

2 R.M. Baum SR. 2016. Future Calculations: The first climate change believer. Distillations. Science History Institute. Summer 2016.; J. Hansen. 2012. Why I must speak out about climate change. TED.

3 Footnote 2.

4 Office of Planning and Research. List of Worldwide Scientific Organizations.

5 IPCC. 2014. Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change: Summary for Policymakers. Geneva. p. 4.

6 G. Readfearn. 2013. IPCC climate change report by numbers. The Guardian. 27 September.

7 IPCC. 2014. Climate Change. 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Geneva. p. viii.

8 13 countries have not yet ratified the Agreement.

9 CO2 is the most abundant GHG.

10 US Environmental Protection Agency. Global Greenhouse Gas Emissions Data.

11 R. Alley. 2015. 4.6 Billion Years of Earth’s Climate History: The Role of CO2. Presented at Symposium—Earths, Moons, Mars & Stars at the National Academy of Sciences’ 152nd Annual Meeting. National Academy of Sciences.

12 Footnote 11. See also A. Gardener. 2017. In Hot Water: Glacier Change and Sea Level Rise. von Kármán Lecure Series: NASA Jet Propulsion Laboratory. A. Gardener also explains how scientists measure CO2 levels and temperatures.

13 Footnote 5.

14 NOAA. 2018. Trends in Atmospheric Carbon Dioxide.

15 Footnote 10.

16 J. Hansen. 2018. Climate Change in a Nutshell: The Gathering Storm. New York. p. 39.

17 NASA Earth Observatory. How is Today’s Warming Different from the Past?

18 Footnote 17.

19 NASA Earth Observatory. World of Change: Global Temperatures.

20 Footnote 5. p. 9. See Figure SPM.5.

21 Footnote 5. pp. 9–10. See Figure SPM.5, representative concentration pathway 8.5.

22 IPCC. 2018. Summary for Policymakers. In: Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty. Geneva.

23 See City of Oakland and the People of the State of California v. BP PLC et al (2018), Case 3:17-cv-06011-WHA and (ii) Juliana v. United States, Case 6:15-cv-01517-AA, in which climate science has been a major issue.

24 See Leghari v. Republic of Pakistan (2015) W.P. No. 25501/2015.

25 Carbon major companies are producers of oil, natural gas, coal, and cement.

26 Republic of the Philippines Commission on Human Rights. 2018. PHL at the forefront of seeking climate justice with CHR’s landmark inquiry on the effects of climate change to human rights. Press Release. 28 March.

27 The United Nations is currently investigating the potential for such an instrument:

28 Executive Order No. 163 of 5 May 1987.

29 See Ioane Teitiota v. The Chief Executive of the Ministry of Business, Innovation and Employment, [2015] NZSC 107; In re: AD (Tuvalu), [2014] Cases 501370-371 (New Zealand); RRT Case Number 0907346, [2009] RRTA 1168, (Refugee Review Tribunal, 10 Dec. 2009) (Australia); Refugee Appeal No. 72189/2000 (Refugee Status Appeals Authority, S. Joe, Aug. 17, 2000) (New Zealand).

30 ADB. 2017. Climate Change in Asia and the Pacific: Infographic.

31 6 of the 10 nations most affected by extreme weather are in Asia and the Pacific. Footnote 30.