They said it is up to governments to decide whether those unprecedented changes are acted upon

increase at the current rate,” the report states.

Deep in the report, 익산출장마사지 scientists say less than 2 percent of 529 of their calculated possible future scenarios kept warming below the 1.5 goal without the temperature going above that and somehow coming back down in the future.

The pledges nations made in the Paris agreement in 2015 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, said.

“I just don’t see the possibility of doing the one and a half” and even 2 degrees looks unlikely, said Appalachian State University environmental scientist Gregg Marland, who isn’t part of the U.N. panel but has tracked global emissions for decades for the U.S. Energy Department. He likened the report to an academic exercise wondering what would happen if a frog had wings.

Yet report authors said they remain optimistic.

Limiting warming to the lower goal is “not impossible but will require unprecedented changes,” U.N. panel chief Hoesung Lee said in a news conference in which scientists repeatedly declined to spell out just how feasible that goal is. They said it is up to governments to decide whether those unprecedented changes are acted upon.

“We have a monumental task in front of us, but it is not impossible,” Mahowald said earlier. “This is our chance to decide what the world is going to look like.”

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, the report said. 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 three to four times more expensive than the less ambitious goal, but it would clean the air of other pollutants. And that would have the side benefit of avoiding more than 100 million premature deaths through this century, the report said.

“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.

Princeton University climate scientist Michael Oppenheimer said extreme weather, especially heat waves, will be deadlier if the lower goal is passed.

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 practically yearly events if the world reaches the hotter of the two goals, the report said.

Coral and other ecosystems are also at risk. The report said warmer water coral reefs “will largely disappear.”

The outcome will determine whether “my grandchildren would get to see beautiful coral reefs,” Princeton’s Oppenheimer said.

For scientists there is a bit of “wishful thinking” that the report will spur governments and people to act quickly and strongly, one of the panel’s leaders, German biologist Hans-Otto Portner said. “If action is not taken it will take the planet into an unprecedented climate future.”