Measures would have to include reducing man-made carbon emissions by 45 per cent by 2030 from 2010 levels, and reaching "net zero" emissions by 2050, the report said.
Limiting warming to 0.9 degrees from now means the world can keep "a semblance" of the ecosystems we have. We can't find any historical analogies for it.
A landmark United Nations report paints a dire picture of the catastrophic consequences the world will face if immediate action is not taken to limit the global warming to 1.5°C, warning that at 2°C, the world could see 10 cm more global sea level rise, loss of all coral-reefs and worsening food shortages.
If emissions can't be cut to a sufficient degree, researchers will need to devise effective methods of removing Carbon dioxide from the air, such as devoting land to growing trees and biofuel crops, Erik Solheim, executive director of the UN Environment Program, tells The Washington Post. The US$2.4 trillion that the climate change panel has calculated as necessary investments is nearly seven times more than that.
If 1.5 degrees of warming does occur, Southeast Asian countries like Indonesia, the Philippines, and Vietnam, including countries like Japan, China, Egypt, and the USA will experience increased flooding by 2040.
Individuals and civic groups have a big role to play in pushing governments to tackle climate threats, and are stepping up pressure as recognition of the danger grows, she said.
At 1.5 degrees, the authors predict the Arctic Ocean will be free of sea ice once per century.
Countries are already seeing an increase in extreme weather and rising sea levels as a result of the increase in average global temperatures of 1 degree above pre-industrial levels that has already occurred, the IPCC study said.
The IPCC report makes clear for the first time that limiting warming to 1.5 degrees requires cutting short-lived super climate pollutions-black carbon, methane, and hydrofluorocarbons-along with carbon dioxide, as well as learning how to pull carbon dioxide out of the atmosphere at scale.
Temperatures are now about 1° C higher than preindustrial levels. "It is also expected to drive the loss of coastal resources, and reduce the productivity of aquaculture", the report says.
Henn was actually responding to Penn State University climate scientist Michael Mann who was pushing back against those criticizing the IPCC report as too "alarmist" in its declarations and warnings.
NH Ravindranath, of the Indian Institute of Science (IISc), who has been an IPCC author and specialises in forestry, says, "Climate change is already impacting natural ecosystems and socio-economic systems even at current level of warming of 1°C".
But success "depends on political leadership", he added. No wonder that the panel is calling for following the 1.5-degree scenario instead of the 2-degree one, which was widely seen as more realistic.
Greenpeace East Asia climate and energy campaigner Walton Li said Hong Kong possessed one of the largest carbon footprints in the world and had a responsibility to "radically" revise its emissions strategy. "In totality, how the rest of the world handles the climate rogue behaviour of the Trump administration will decide whether the world meets the 1.5°C goal or not". Denying the reality of climate change is not going to help anyone. One recent report calculated the benefits at $26 trillion.
Currently, the world has seen 1C of warming over the past 115 years, according to a U.S. report last year. "The report would not have been released without consensus of all".