“Net CO2 emissions at the global scale must reach zero by 2050”, said Valerie Masson-Delmotte, a climate scientist at France’s Alternative Energies and Atomic Energy Commission in Paris and a key participant in drafting the report. 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 good news is that some of the kinds of actions that would be needed to limit global warming to 1.5 °C are already underway around the world, but they would need to accelerate”, said Valerie Masson-Delmotte, Co-Chair of Working Group I.
Avoiding going even higher will require significant action in the next few years, the report said.
“By 2100, global mean sea level rise will be around 10cm lower for warming of 1.5 degrees compared with 2C”.
This report says that the world doesn’t have to come up with some magic machines to curb climate change – we’ve already got all the tech we need.
Governments invited the IPCC to prepare the report in 2015 when they adopted the Paris Agreement to combat climate change.
On a jarring note, the USA announced that it accepted the report – in effect stopped short of vetoing it – but it did not endorse the content and the findings in the report.
“The report shows that we only have the slimmest of opportunities remaining to avoid unthinkable damage to the climate system that supports life as we know it”, said Amjad Abdulla, the IPCC board member and chief negotiator for an alliance of small island states at risk of flooding as sea levels rise. The technology to do this is in the early stages of development and many researchers say it could be hard to develop it for use on a global scale.
Ninety-one authors and review editors from 40 countries prepared the IPCC report, which contains 6,000 scientific references.
“International cooperation is absolutely imperative to limit emissions and therefore global warming and its impacts, as well as coordinating effective and widespread adaptation and mitigation”, said Sarah Perkins-Kirkpatrick, a fellow at the Climate Change Research Center at the University of New South Wales. 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.
If temperatures go up by 2C, then nearly all coral reefs in the world would start dying off, according to the report.
This means no more Carbon dioxide should be put out than is being removed by current measures, such as planting trees.
According to the report published on Monday, if world temperatures do indeed rise by two degrees Celsius, India could see deadly heat waves increase in frequency and become an annual condition.
The panel says that keeping warming to 1.5 degrees C is technically feasible, but the emissions cuts pledged so far by the nations that signed the Paris agreement fall far short of what’s needed.
The report found that if greenhouse gas emissions continue to grow at their current rate, the earth’s atmosphere will warm up by as much as 1.5ºC above pre-industrial levels by 2040. To give just one example, Yale scientists predict that the difference between a 1.5 degree and 2 degree rise in global temperatures could cut corn yields in parts of Africa by half. “Consequently, limiting global warming to 1.5°C is projected to reduce risks to marine biodiversity, fisheries, and ecosystems, and their functions and services to humans, as illustrated by recent changes to Arctic sea ice and warm water coral reef ecosystems”.
Two of the most intense typhoons on record have hit the city in the last two years – Hato last year and Mangkhut last month.
Monday’s report was produced by three IPCC working groups.
“The challenges from delayed actions to reduce greenhouse gas emissions include the risk of cost escalation, lock-in in carbon-emitting infrastructure, stranded assets, and reduced flexibility in future response options in the medium to long-term”, it added.
The report makes it evidently clear that a 1.5°C world would witness greater sea level rise, increased precipitation and increased frequency of droughts and floods, more hotter days and heatwaves, more intense tropical cyclones, increased ocean acidification and salinity.