New national pledges to tackle climate change this decade would lead to around 2.4 degrees Celsius of global warming this century, far above safe levels, analysts predict.
Climate Action Tracker (CAT) said on Tuesday that the promises by countries attending the UN summit in Glasgow to cut greenhouse gas emissions by 2030 would still allow the Earth to heat up far beyond the United Nations target by 2100, reports Reuters.
"Even with all new Glasgow pledges for 2030, we will emit roughly twice as much in 2030 as required for 1.5°C," it said, referring to the aspirational goal for warming since pre-industrial levels set down in the 2015 Paris Agreement.
"Therefore, all governments need to reconsider their targets."
In an "optimistic scenario" where some countries' longer-term goals to stop increasing the level of greenhouse gases in the atmosphere - "net zero" - by 2050 or later were implemented, warming could be limited to 1.8C this century, CAT added. That echoed an analysis last week by the International Energy Agency.
CAT warned against assuming the longer-term pledges would be met, however, since most countries have not yet implemented the short-term policies or legislation needed to get on track for those goals.
"It’s all very well for leaders to claim they have a net-zero target, but if they have no plans as to how to get there, and their 2030 targets are as low as so many of them are, then frankly, these 'net zero' targets are just lip service to real climate action," said Bill Hare, CEO of Climate Analytics, one of the organisations behind the CAT.
Under "business as usual", without any of the new pledges, the world would warm up by 2.7C this century, CAT said.
All scenarios will blow past the 1.5C limit that scientists say the world must meet to avert the most devastating impacts of climate change. To keep to that, scientists have said global greenhouse gas emissions - mostly the carbon dioxide emitted by burning coal, oil and gas - must fall 45% by 2030 from 2010 levels, and reach net zero by 2050.
Roughly 90 per cent of global emissions are now covered by a net-zero target, but the "vast majority" of countries' climate plans for the next decade are inconsistent with long-term net-zero targets, CAT said.