A new analysis, seen by the BBC, suggests the goals of the UN Paris climate agreement are getting "within reach."
The Climate Action Tracker group looked at new climate promises from China and other nations, along with the carbon plans of US President-elect Joe Biden.
These commitments would mean the rise in world temperatures could be held to 2.1C by the end of this century.
Previous estimates indicated up to 3C of heating, with disastrous impacts.
But the experts are worried the long-term optimism is not matched by short-term plans to cut CO2.
For more than a decade, researchers from the Climate Action Tracker have kept a close eye on what countries' collective carbon-cutting pledges mean for our warming world.
After the failed Copenhagen summit in 2009, the group estimated that global temperatures would rise by 3.5C by the end of this century.
But the creation in 2015 of the Paris climate agreement, which was designed to avoid dangerous warming of the Earth, made a considerable impact. As a result of the international deal, countries slowly started to switch away from fossil fuels.
In September this year, the group concluded that the world was heading for warming of around 2.7C by 2100.
This figure was still far above the 2C goal contained in the wording of the Paris pact, and nowhere near the more challenging 1.5C target that scientists endorsed as the threshold to destructive warming in 2018.
Their new "optimistic analysis" now suggests a rise of 2.1C by 2100.