It was written by 91 authors from 40 countries and approved by the Intergovernmental Panel on Climate Change on Saturday.
Half a degree doesn't sound like much, but the difference between an average temperature rise of 1.5 degrees celsius and 2 degrees celsius is a dead Great Barrier Reef.
But the agreement's more ambitious goal was to prevent temperatures from rising more than 1.5 degrees C. That's because even 1.5 degrees of warming will cause catastrophic effects, including more intense storms, searing heat waves, mass extinctions, and droughts.
He admitted the report showed that "limiting warming to 1.5°C is barely feasible and every year we delay the window of feasibility halves".
That could reduce flooding and give the people that inhabit the world's coasts, islands and river deltas time to adapt to climate change.
Given that current national commitments on greenhouse-gas emissionsfall well short of the goals laid out in the Paris climate agreement, many scientists have argued that meeting even the 2 °C goal is virtually impossible. 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.
Another recent report from the consulting firm PwC makes it clear that even limiting warming to 2 degrees C will be a stretch: "There seems to be nearly zero chance of limiting warming to well below two degrees (the main goal of the Paris Agreement), though widespread use of carbon capture and storage technologies, including Natural Climate Solutions, may make this possible", it says. Global net emissions of carbon dioxide would need to fall by 45 per cent from 2010 levels by 2030 and reach "net zero" around 2050.More news: Maurizio Sarri thinks this goal has been Chelsea’s best
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"Limiting warming to 1.5°C, compared with 2°C, is projected to result in smaller net reductions in yields of maize, rice, wheat, and potentially other cereal crops, particularly in sub-Saharan Africa, Southeast Asia, and Central and South America", it added.
So far, Prime Minister Scott Morrison has said that he's "not going to spend money on global climate conferences and all that nonsense", while Deputy PM Michael McCormack described the landmark United Nations warning as "some sort of report" and said Australia will "absolutely" keep relying on coal-fired power.
The basic gist is hardly surprising-the impacts of 1.5°C warming are slightly less than 2.0°C, and it's harder to cut greenhouse gas emissions fast enough to meet the lower target.
Harald Winkler‚ director of the Research Energy Centre at UCT‚ said limiting warming to 1.5ºC would require "changes on an unprecedented scale and pace".
India could face an annual threat of deadly heatwaves, similar to the one in 2015 that had left around 2,500 people dead, if the world gets warmer by 2 degree Celsius over pre-industrial levels, a United Nations report stated. The sea level will still rise, and there always be more extreme weather events and natural disasters, but these won't be as extreme as the worst case scenario we're now headed for.
"The science in the IPCC report on 1.5°C speaks for itself".
The IPCC's most recent (2014) Fifth Assessment of the scientific evidence found that at around 1.5℃ warming there was a transition from moderate to high risk for threatened ecosystems and cultures and for extreme weather events.
Last March, Scientific American invited its readers to "chill out" over global warming, insisting that doomsday scenarios attributed to climate change are simply false and the human race will be able to accommodate gradual changes in global temperatures.
Hong Kong's climate action plan, published past year, only pledges a 26 to 36 per cent cut by 2030 from 2005 levels. "The next few years will be critical in the evolution of these efforts". Denying the reality of climate change is not going to help anyone.