Climate change is arguably the biggest threat facing the world, but it is one that governments appear to find easy to put on the back burner.
Now a report released this week by the UN Intergovernmental Panel on Climate Change (IPCC) carries a warning stark enough to make most decision-makers sit up and take notice.
The message is that we have just 12 years to bring carbon dioxide emissions down low enough to limit global warming to a 1.5°C increase.
Emissions must come down by 45% by 2030 and reach zero by 2050. Essentially coal has to go, renewables must be ramped up and there must be fundamental changes in four major global areas: energy, transport, industry and cities.
Running out of time
Climate change is happening faster than anticipated, and the IPCC’s Special Report on Global Warming, compiled by the world’s leading climate scientists, stresses the need for urgency in taking action now.
Debra Roberts, the IPCC’s co-chair and head of climate protection in eThekwini Municipality in Durban, describes the report as the "largest clarion bell from the science community".
"It’s a line in the sand and what it says is that this is the moment and we must act now. I hope it mobilises people and dents the mood of complacency."
The report, seen as the main scientific guide for world governments on how to implement the Paris Agreement, says the world had already reached a 1°C rise in temperature from humanity’s greenhouse gas emissions.
This seemingly small increase has had a big effect, and has resulted in a trend of extreme weather events of increasing frequency and severity, ranging from floods and droughts to hurricanes, heat waves and devastating fires. These have come with a high cost to society and the economy on a global scale.
Ocean temperatures are rising; so are sea levels, while the Arctic ice is melting and corals dying. These too will come with increasing costs in the longer term.
Closer to home, Capetonians have felt the hard edge of the worst drought on record, with the recent prospect of city taps running dry. Residents of Knysna, who had also suffered a prolonged drought in what is normally a relatively high rainfall region, watched helplessly last year as hundreds of houses burned down in a devastating fire that burned for weeks, killing seven people.
Into this increased awareness the IPCC report arrived with its message that we have just a small window to stop climate change from moving into a higher gear.
A dismal showing
The IPCC report stems from the UN climate talks in France in 2015 that gave rise to the Paris Agreement, signed by 195 nations.
Nations pledged then that they would aim to keep increases in the average global temperature to "well below" a 2°C increase compared with the level before the Industrial Revolution, and would try to limit it to a 1.5°C increase.
Each country also pledged to cut emissions by a particular amount and set down their targets. It was a dismal showing. When all the pledges were added up, it was revealed that if that was the best world governments would do, we were set on a course of 3°C warming.
The IPCC were asked at the meeting to produce a report on a 1.5°C increase compared to a 2°C increase, what the effects would be, and what pathways the world needed to take to keep to a 1.5°C target.
The answer is that limiting global warming to 1.5°C would require "rapid, far-reaching and unprecedented changes in all aspects of society". It also showed that a mere half a degree increase came with substantially more serious effects.
The required cuts in carbon would mean radical changes in energy, land use, buildings, industry, transport and cities.
Carbon emissions would have to come down by 45% from 2010 levels, and by 2050 carbon emissions must have reached zero.
For that to happen, the generation of energy from coal would have to decline by 78% from 2010 levels, while renewable energy would have to supply between 70 to 85% of global electricity by 2050, compared to about 25% today.
It would cost a lot – a $2.4trn investment every year to 2035 – but the cost of not doing so would be far higher.
Bloomberg says the investment needed would be seven times higher that the annual estimate of $333.5bn invested in renewables last year. Total investment in energy systems in 2017 was $1.8trn.
The good news
The good news is that many of these transitions to a low carbon economy are already underway, such as South Africa’s renewable energy programme. What needs to happen is for these initiatives to speed up fast.
There is more good news: The report says limiting warming to 1.5°C is entirely possible from a scientific and technological point of view, while keeping climate change within this increase would reduce bad effects on ecosystems and on human health and well-being.
The difference between a 1.5°C and 2°C warming may sound insignificant, but as the report shows, the effects of just that half a degree difference can be profound.
For instance, at a 1.5°C increase the number of people exposed to water shortages could be 50% lower than at 2°C. Sea level rise would affect 10 million more people by 2100 at 2°C, while hundreds of millions more people would suffer from food scarcity at 2°C compared with 1.5°C.
Overall, risks to health, livelihoods, food security, water supply and economic growth will increase with global warming of 1.5°C - and increase even more at 2°C.
The 0.5°C rise in global temperatures that we have seen in the last 50 years has resulted in shifts in the distribution of plant and animals species, decreasing crop yields and more frequent wildfires. Similar changes can be expected with further increases, the report said.
Will world governments continue to leave climate action on the back burner, or will this report scare them into action?
Jim Skea, a co-chair of one of the IPCC working groups, acknowledges this is the big unknown.
"We have presented government with pretty hard choices. We have pointed out the enormous benefits of keeping to 1.5°C, and also the unprecedented shift in energy systems and transport that would be needed to achieve that.
"We show it can be done within the laws of physics and chemistry. Then the final tick box is political will. We cannot answer that. Only our audience can – and that is the governments that receive it."
The Summary for Policymakers of the Special Report onGlobal Warming of 1.50C is available at http://www.ipcc.ch/report/sr15/or www.ipcc.ch.
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