There are several events whose attribution has not been addressed but that received an enormous amount of media attention, one example being Super Typhoon Haiyan/Yolanda. The ocean heat content (OHC) and sea level in the region had increased a great deal since 1993 and especially since 1998. Consequently, as the typhoon approached the Philippines, it was riding on very high sea surface temperatures (SSTs) with very deep support through the high OHC, and the strong winds and ocean mixing did not cause as much cooling as would normally be experienced, probably helping the storm to maintain its tremendous strength. Moreover, the storm surge was without a doubt exacerbated considerably by the sea levels, which were some 30 cm above 1993 values. Although natural variability played a major role, there was also a global component through increased OHC from the Earth’s energy imbalance. Observations of the 2010 Russian heat wave and the recent California drought, among others, are also consistent with the view that it is the combination of natural variability (weather, El Niño, etc.) and climate change when they go in the same direction that causes record-breaking extreme weather. 177 The changes in extremes have huge environmental, economic, and social costs. However, there is no clean separation as to how much should be ascribed to human influences. In one sense, the extreme event would not have happened without global warming, because otherwise the impacts of the event would have been well within previous experience. If this is accepted, then the whole cost of an extreme event might be so assigned. 178 IV. Attribution of Climate Change Impacts to the Carbon Majors (ClientEarth, Plan B) The Commission has before it detailed evidence of the previous activities of the Carbon Majors, in the form of the thorough expert evidence of Richard Heede of the Carbon Accountability Institute. This work is the only example of research linking anthropogenic greenhouse gas emissions since 1850 to the operations and products of private actors. The key finding of the research is that GHG emissions totaling 914.3 Gt of CO 2 equivalent (CO2e) produced between 1854 and 2010 (equivalent to 63% of estimated global industrial CO2 and methane emissions between 1751 and 2010) can be traced to the operations and products of the 90 Carbon Major groups of companies included in the analysis. 179 Of the 90 Carbon Majors included in the original study, 51 of those privately-owned groups of companies have been included in the scope of the Petition. Based on Heede’s research, these 51 companies contributed around one fifth of all global greenhouse gas emissions since 1854. The operations and products of the Carbon Majors named in the Petition continue to be significant contributors to global greenhouse gas emissions. 180 For example, Chevron disclosed 177 Id. at p. 4. Id. 179 Richard Heede, Tracing anthropogenic carbon dioxide and methane emissions to fossil fuel and cement producers, 1854-2010, 122 CLIMATIC CHANGE 229 (2013) (in Annex D3 to the Petition); see also Annex D to the Greenpeace Petition, Updated Details of Carbon Majors Publications. A 2017 update to this research demonstrated that over half of global industrial emissions since 1988 can be traced to just 25 corporate or state producers. See CDO, THE CARBON MAJORS DATABASE (2017), https://www.cdp.net/en/reports/downloads/2327. 180 Based on information disclosed both voluntarily to organizations such as CDP and under mandatory reporting laws in various jurisdictions, for example, see Chevron‘s CDP 2015 Response, https://www.chevron.com//media/chevron/corporate-responsibility/documents/CDP-2015.pdf. 178 38