Climate Change Revisited
“Limiting global warming to 1.5℃ would require rapid, far-reaching and unprecedented changes in all aspects of society.” So wrote the Intergovernmental Panel on Climate Change (IPCC) in its press release announcing findings of a new report. The IPCC met in Incheon, Republic of Korea in October 2018. The report was produced at the request of the United Nations Framework Convention on Climate Change (UNFCCC) when UNFCCC adopted the Paris Agreement in 2015.
The agreement signed in Paris by 195 nations seeks to keep global temperatures within 2.0℃ of pre-industrial times, and ideally go beyond that to limit temperatures to within 1.5℃. The target is based on atmospheric temperature in the 1850s, when large-scale burning of coal began. Scientists estimate that human activity has caused temperatures to increase 1.0℃ since the 1850s, more than halfway to the 1.5℃ mark. Continued emission of greenhouse gases at the current rate would warm the atmosphere to the 1.5℃ level by 2040.
The IPCC report concluded that pledges to reduce greenhouse gas emissions made at the Paris climate conference in 2015 will be insufficient to avoid temperatures rising to the 2.0℃ level. At that temperature sea level rise will displace millions of people in Japan, the Philippines, China, India, Indonesia, Vietnam, Bangladesh, Egypt and the United States. Arctic summers will be ice-free one out of ten years. Extremely hot days will become more common and severe, causing more deaths and more forest fires. Pollination of crops and plants will suffer from the loss of insects. Most of the world’s coral will be lost. The cost of damages is projected to grow to $69 trillion.
Thus far, progress on achieving pledged reductions in emission of greenhouse gases has not occurred. Furthermore, the United States, the second-largest greenhouse gas emitter, has announced its intention to pull out of the Paris accord, and Brazil may follow, pending a decision by the newly-elected President Jair Bolsonaro. Commitments are being made to future coal-based energy production, even though the IPCC report is unequivocal in asserting that there is no way to mitigate climate change without eliminating coal as an energy source.
These trends must be reversed in order to limit warming to 1.5℃. According to the press release, doing so “is possible within the laws of chemistry and physics but doing so would require unprecedented changes,” in land use, energy, industry, buildings, transport and cities. Reforestation, carbon capture and electric transport systems are among the essential elements of plans to meet greenhouse gas reduction goals.
The IPCC report will be a key scientific input when signatory governments again meet in Poland in December 2018 for the Katowice Climate Change Conference.