Special IPCC Report on Global Warming of 1.5 °C (SR15)

The IAI participated in the 48th Session of the Intergovernmental Panel on Climate Change (IPCC-48) from 1 to 5 October in Incheon, Korea, which approved the report Global Warming of 1.5 ºC, an IPCC special report on the impacts of global warming of 1.5 ºC 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.

Global Warming of 1.5ºC is the first in a series of Special Reports to be produced in the IPCC’s Sixth Assessment Cycle. Next year the IPCC will release the Special Report on the Ocean and Cryosphere in a Changing Climate, and Climate Change and Land, which looks at how climate change affects land use.

The report highlights a number of climate change impacts that could be avoided by limiting global warming to 1.5ºC compared to 2ºC, or more. For instance, by 2100, global sea level rise would be 10 cm lower with global warming of 1.5°C compared with 2°C. The likelihood of an Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5°C, compared with at least once per decade with 2°C. Coral reefs would decline by 70-90 percent with global warming of 1.5°C, whereas virtually all (> 99 percent) would be lost with 2°C.

Half a degree of global warming will sigficantly impact agriculture production and crop yields in the region. “Agriculture production and crop yields are sensitive to temperature and draught. Reduced impact on crop production of maize, rice and wheat (which are major global cereal products, besides soy) refers to reduced climate impact on production areas for 1.5C in relation to a 2.0C warmer world. There has been substantial advances on crops genetics to help agriculture adapt to a warmer world but we need to keep in mind that with a changing climate we will also see an increase in extreme events that can severely impact crop production” said Dr. Jean Ometto, lead author of the AR6 Working Group II Chapter 12 Central and South America and principal investigator of IAI research network Nitrogen cycling in Latin America: drivers, impacts and vulnerabilities .

The report finds that limiting global warming to 1.5°C would require “rapid and far-reaching” transitions in land, energy, industry, buildings, transport, and cities. Global net human-caused emissions of carbon dioxide (CO2) would need to fall by about 45 percent from 2010 levels by 2030, reaching ‘net zero’ around 2050. This means that any remaining emissions would need to be balanced by removing CO2 from the air.

The report had unprecedented interdisciplinarity and collaboration among scientists involved, with 91 authors from 40 countries, 133 contributing authors, over 6000 cited references and 42,001 expert and government review comments.

Download the report: /admin/site/sites/default/files/sr15_spm_final.pdf













 

The Paris Agreement sets a long-term goal of holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit it to 1.5 °C. The report will be the main scientific input at the upcoming Climate Change Conference (UNFCCC COP-24) to be held in Katowice, Poland from 2 to 14 December.