Last updated November 7, 2018 at 3:55 pm
IPCC points out the big difference half a degree could make.
We’re facing a dire future unless we act on climate change, according to a Special Report on Global Warming of 1.5°C from the Intergovernmental Panel on Climate Change (IPCC) released this week.
The report, featuring contributions from thousands of experts worldwide and containing over 6000 scientific references, highlights several impacts of climate change that could be avoided if we take steps to limit global warming to 1.5°C, compared to 2°C or more.
There is a summary of the report here. Following are some responses from experts in Australasia.
Dr Sarah Perkins-Kirkpatrick from the University of NSW points out that it is important to remember we have already warmed by 1°C above pre-industrial conditions and that “the difference between worlds that are 1.5°C and 2°C warmer than pre-industrial levels by 2100 is measurable and significant”.
She’s not wrong. Even a 1.5°C warmer world could see 3°C hotter heatwaves, a coral reef loss of 70-90% and a 26-77 cm rise in sea levels by 2100. With warming of 2°C, heatwaves could be 4°C hotter, coral reefs could disappear entirely, and sea levels could rise an extra 10 cm, putting another 10 million more people at risk of displacement from flooding.
“Adverse impacts on human health at 1.5°C compared to 2°C would also be reduced, particularly in terms of impacts from vector-borne diseases, heatwaves and ozone pollution,” she says.
Time for action is now
Dr Jatin Kala from Murdoch University in WA makes one simple but powerful point: while 1.5°C-2°C doesn’t sound like much, it’s an average figure that represents significant changes globally. “1.5°C refers to an increase in the global … average,” he says. “Many regions will be experiencing substantially higher levels of warming, especially over land. The time for action is right now.”
Associate Professor Bronwyn Hayward from the University of Canterbury in New Zealand notes that this is the first time a climate change report has been framed in a social context. It’s not just about the huge effort of holding the climate at 1.5°C, it’s about trying to do that while thinking about sustainable development and eliminating poverty.
“If we don’t make these really difficult, real, unprecedented cuts now, we will have fewer options for sustainable development, for our economies, and we’ll be forced to rely more on unproven, risky and potentially socially undesirable forms of carbon removal,” she says.
Power and transport
Dr Peter Newman of Curtin University in WA says the most significant thing people can do is reduce their use of power and transport, which are oil-based. “There are things you can do with electric cars but you can also change to using more public transport or biking or walking more or reducing the need for heating and cooling,” he says.
“The power of this report is that it’s not a simple thing any more to say: ‘Governments, get going and fix it for us’. We’ve all got to play our part.”
Professor Will Steffen from the Climate Council of Australia says small- and large-scale changes are tough but necessary and will cost less than the excess climate change damage. “We are indeed suffering a very heavy cost for past decades of inaction on climate change,” he says. “Business-as-usual, or minor modifications of it, will be totally inadequate to meet this challenge.”
What next? UQ Global Change Institute Director Professor Ove Hoegh-Guldberg has high hopes.
“I hope that governments and the public read this important document and begin the deep and concerted action required to avoid the serious impacts of reaching and exceeding global warming of 2°C,” he says. “We are at one-minute-to-midnight on the clock showing the time left to act on climate change.”