Memorandum for the Petitioners | 38 action would lead to increasingly negative impacts on land and reduce the prospect of sustainable development.125 5.23. The evidence of the IPCC is clear and unequivocal: climate change is already having major impacts on natural systems, human health, livelihoods, food security, the achievement of SDGs, and human rights. c r 5.24. As stated by the recent IPCC SRI .5 and SRCCL , and reported in the United Nations Special Rapporteur’s on the Right to a Healthy Environment’s 2019 Safe Climate Report, at current temperature levels, humanity is already experiencing the frequency, intensity, and duration of extreme weather events, melting of glaciers and ice sheets, rising sea levels, storm surges, saltwater intrusion, ocean acidification, changes in precipitation , flooding, heatwaves, droughts, wildfires, increased air pollution, desertification, water shortages, the destruction of ecosystems, biodiversity loss, and the spread of waterborne and vector-borne disease.»126 5.25. Some experts in the National Inquiry have submitted that the best climate science indicates that, to protect the earth’s systems, the long-term increase in the average global surface temperature of the Earth above pre industrial temperatures must stay below 1°C.127 5.26. Peer-reviewed research shows that populations around the world are already experiencing significant and varied impacts from the 1°C warming that has occurred. These impacts constitute harbingers of far more dangerous, irreversible, and uncontrollable changes to come, as climate and biological systems pass critical tipping points.128 As the science indicates, there are no safe levels of warming . c. Impacts felt and projected can be attributable to specific human activities 5 .27. According to IPCC AR5 , “the causes of observed changes in the climate system , as well as in any natural or human system impacted by climate, are established following a consistent set of methods. Detection addresses the question of whether climate or a natural or human system affected by climate has actually changed in a statistical sense, while Id. Sec. D3, p. 40. UN Human Rights ( 15 July 2019), Report of the Special Rapporteur on the Issue of Human Rights Obligations Relating to the Enjoyment of a Safe, Clean, Healthy and Sustainable Environment ( hereinafter, UNSR Safe Climate Report”), p. 25, available at https://undocs.Org/en/A/74/161 (last accessed on 12 September 2019). 127 Joint Summary of the Amicus Curiae, supra note 50, pp. 34-35 (citations omitted ). 128 125 126 Id.