A report on global warming life-or-death-warning

Preventing an extra single degree of life could make a life-or-death difference in the world for many people and ecosystems on this fast-warming planet, an international panel of scientists reported Sunday. But they provide little hope the world will rise to the challenge.

The Nobel Prize-winning Intergovernmental Panel on Climate Change issued at its meeting in Incheon, South Korea.

In the 728-page document, the UN organization detailed how Earth's weather, health and ecosystems would be in better shape if the world's leaders could somehow 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 degree C). Among other things:

• Half as many people will suffer from lack of water.
• There would be fewer deaths and illnesses from heat, smog and infectious diseases.
• Seas would be about 4 inches (0.1 meters) less.
• Half of many animals with back bones and plants would lose the majority of their habitats.
• There would be fewer heat waves, downpours and droughts.
• West Antarctic ice sheet might not kick into irreversible melting.
• And it just can be enough to save most of the world's coral reefs from dying.

"For some people this is a life-or-death situation with a doubt," said Cornell University climate scientist Natalie Mahowald, a lead author on the report.

Limiting warming to 0.9 degrees from the world can keep "a semblance" of the ecosystems we have. Ove Hoegh-Guldberg, director of the Global Change Institute at the University of the United States of America Queensland, Australia.

But warming would require immediate, draconian cuts in emissions of heat-trapping gases and dramatic changes in the energy field. While the U.N. panel says technically that's possible, it does not matter what happens.

In 2010, international negotiators adopted a goal of limiting warming to 2 degrees C (3.6 degrees F) since pre-industrial times. It's called the 2-degree goal. In 2015, when the nations of the world agreed to the climate change, they set dual goals: 2 degrees C and a more demanding target of 1.5 degrees C from pre-industrial times. The 1.5 was at the urging of vulnerable countries that called 2 degrees a death sentence.

The world has already warmed 1 degree C since pre-industrial times, so the talk is really about the difference of another half-degree C or 0.9 degrees F from now.

"There is no definitive way to limit global temperature rise to 1.5 above pre-industrial levels," the U.N.-requested report said. More than 90 scientists wrote the report, which is based on more than 6,000 peer reviews.

"Global warming is likely to reach 1.5 degrees C between 2030 and 2052 if it continues to increase," the report states.

Deep in the report, scientists say less than 2 percent of 529 of their calculated future future scenarios are keeping pace with 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.

Said I just App unlikely App unlikely said unlikely said unlikely said unlikely said unlikely said unlikely said unlikely said unlikely said unlikely said unlikely App unlikely App unlikely App unlikely the US 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 remedies to be reduced to just how feasible that goal is. They say it is up to governments to decide whether or not to change the situation.

"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. Emissions of other greenhouse gases, such as methane, also will have to drop. Switching away from fossil fuels like coal, oil and gas to do more expensive than the less ambitious goal, but it would be clean 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 the global warming" report said, adding that the world is more likely to get hit hard.

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 be more than 1,000 million people being exposed to extreme heat waves," the report said. The deadly heat waves that hit India and Pakistan in 2015, the report said.

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

The outcome would 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 be one of the leading panelists, German biologist Hans-Otto Portner, said. "If action is not taken it will take the planet into an unprecedented future climate."

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