Answer: The IPCC Working Groups were asked by countries that are most vulnerable to climate change impacts to analyze what will happen with a 1.5 degree Celsius rise in global temperatures - before we ever reach a 2 degree rise.
Written and edited by 91 scientists from 40 countries who analyzed more than 6,000 scientific studies, this report was done at the request of small island nations who worry about warming changes that are short of those predicted as part of the Paris agreements.
More research is needed in the area, but the relationship between climate change-induced environmental stressors and mental health seems like yet another important reason to help fight climate change.
It warns that the world is rapidly running out of time before catastrophic effects on the planet take place. We've moved from an era of "you first" to "follow me" - it's time for the rich world to do just that. 12 years. The world only has 12 years left to try and fix the irreparable damage we have created.
"It provides hope. While clearly indicating the gravity of the situation, it also tells us that it's still possible to cap the warming at 1.5 and, beyond previous reports, we now have specific information to make that case", Spence noted.
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Nordhaus concluded that the most efficient approach was to deploy carbon taxes , applied uniformly to different countries. A number of climate change impacts could be avoided by limiting global warming to 1.5ºC compared to 2ºC, or more.
Even worse, if we remain at our current levels of emissions, we are on a path to warming 4 C above pre-industrial levels by 2100, which if reached would trigger a chain of cataclysmic changes that include extreme heatwaves, declining global food stocks, substantial species extinctions and sea-level rising that would affect hundreds of millions of people, according to the report.
The IPCC recommended several steps needed to reverse carbon dioxide emissions, including replacing the use of fossil fuels with renewable energy such as wind and solar, as well as growing more forests, which naturally recycles CO2.
Now that we're through the breathlessness of the Supreme Court confirmation hearings, perhaps one of those adults in the room could put a pictorial summary of what this report says is happening on the president's desk.
Farmers for Climate Action chief executive Verity Morgan-Schmidt said the government needs to have a fully-funded national strategy on agriculture and climate change.
That's right - the one country that pulled out of the phony Paris Climate Accord reduced its carbon emissions by 0.5 percent, the most of all major countries.
Friends of Science says the WSJ paragraph in which Lomborg describes the economic impact on Europe of cutting emissions 80% by 2050 should be front page news in every newspaper in Europe and North America.
"Today we have underlined again that the European Union will continue to lead the way in global action on climate action".
Trump's unusual, dismissive comments about the IPCC report came as Hurricane Michael bore down on Florida.