Preventing an extra single degree of heat could make a life-or-death difference in the next few decades for multitudes of people and ecosystems on this fast-warming planet, warned a report from the Intergovernmental Panel on Climate Change (IPCC), last week.
The report from the Nobel Prize-winning UN organisation details how the Earth’s weather, health and ecosystems would be in better shape if the world’s leaders could limit future human-caused warming to just 0.9 degrees Fahrenheit (a half degree Celsius) from now, instead of the globally agreed-upon goal of 1.8 degrees F (1°C). If we succeed, among other things:
• Half as many people would suffer from lack of water
• There would be fewer deaths and illnesses from heat, smog and infectious diseases
• Seas would rise nearly 4 inches (0.1 metres) less
• Half as many animals with backbones and plants would lose the majority of their habitats
• There would be substantially fewer heat waves, downpours and droughts
• The West Antarctic ice sheet might not kick into irreversible melting
• And it just may be enough to save most of the world’s coral reefs from dying
“For some people, this is a life-or-death situation without a doubt,” said Cornell University climate scientist Natalie Mahowald, a lead author on the report.
Glimmer of Hope
Limiting warming to 0.9 degrees from now means the world can keep ‘a semblance’ of the ecosystems we have. Adding another 0.9 degrees on top of that — the looser global goal — essentially means a different and more challenging Earth for people and species, said another of the report’s lead authors, Ove Hoegh-Guldberg, director of the Global Change Institute at the University of Queensland, Australia.
But meeting the ambitious goal of slightly less warming would require immediate, draconian cuts in emissions of heat-trapping gases and dramatic changes in the energy field. While the UN panel says technically that’s possible, it saw little chance of the needed adjustments happening.
In 2010, international negotiators adopted a goal of limiting warming to 2°C since pre-industrial times. In 2015, the historic Paris climate agreement set two goals: 2°C and a more demanding target of 1.5°C from pre-industrial times (at the urging of vulnerable countries that called 2°C a death sentence. The world has already warmed 1°C since pre-industrial times, so it’s really about the difference of another ½°C from now.
“Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rates,” stated the report written by over 90 scientists, based on over 6,000 peer reviews adding that “less than 2% of 529 of their calculated possible future scenarios kept warming below the 1.5 goal.
The Paris pledges are “clearly insufficient to limit warming to 1.5 in any way,” one of the study’s lead authors, Joerj Roeglj, of the Imperial College in London, stressed.
“Limiting warming to the lower goal is “not impossible but will require unprecedented changes”, pointed out the UN panel chief Hoesung Lee. “We have a monumental task in front of us, but this is our chance to decide what the world is going to look like,” added Mahowald.
To limit warming to the lower temperature goal, the world needs “rapid and far-reaching” changes in energy systems, land use, city and industrial design, transportation and building use, said the report. Annual carbon dioxide pollution levels that are still rising now would have to drop by about half by 2030 and then be near zero by 2050. Emissions of other greenhouse gases, such as methane, also will have to drop.
Switching away rapidly from fossil fuels like coal, oil and gas to do this could be expensive but it would clean the air of other pollutants, apart from the side benefit of avoiding more than 100 million premature deaths through this century, pointed out the report.
“Climate-related risks to health, livelihoods, food security, water supply, human security and economic growth are projected to increase with global warming”, the report said, adding that the world’s poor are more likely to get hit hardest.
Meeting the tougher-to-reach goal “could result in around 420 million fewer people being frequently exposed to extreme heat waves, and about 65 million fewer people being exposed to exceptional heat waves,” the report said. The deadly heat waves that hit India and Pakistan in 2015 will become yearly events if the world reaches the hotter of the two goals.
Just a day after the UN panel called for urgent action on climate change, the Nobel Prize in economics was awarded to an American researcher for his work on the economics of a warming planet and to another whose study of innovation raises hopes that people can do something about it.
The Royal Swedish Academy of Sciences awarded the $1 million prize to William Nordhaus of Yale University and to Paul Romer of New York University. Nordhaus, 77, who has been called “the father of climate-change economics,” developed models that suggest how governments can combat global warming. He has endorsed a universal tax on carbon, which would require polluters to pay for the costs that their emissions impose on society.
Romer, 62, who has studied why some economies grow faster than others, has produced research that shows how governments can advance innovation. “Many people think that protecting the environment will be so costly and so hard that they just want to ignore the problem,” said Romer.
David Warsh, a blogger who follows economic research and has written a book on Romer’s work, said he thought it was no coincidence that the Nobel committee decided to honour Nordhaus and Romer at a time of escalating alarm over climate change. “Darn right they were sending a message,” stressed Warsh.