Earth is hurtling toward nearly 3°C of warming: Report
The globe is headed for nearly 3°C (5.4°F) of warming compared with preindustrial levels through 2100, new data finds, even if current policies to cut planet-warming emissions are met.
Driving the news: The United Nations' 2023 "Emissions Gap Report" details the distance between pledged greenhouse gas emissions cuts made by countries and the reductions needed to be on course to meet Paris targets.
- The information in this year's edition is designed to inform negotiators at the COP28 climate summit in Dubai that begins at the end of the month.
- The summit will feature the first "Global Stocktake," which will set up national pledges to cut emissions between 2025 and 2035.
Why it matters: The report acknowledges previous findings that have shared the same main conclusion, but with different numbers: the world is far off track in its efforts to contain global warming.
Zoom in: A warming of about 3°C would greatly exceed the 1.5°C and 2°C Paris targets.
- The report also found that fully implementing emissions pledges, known as Nationally Determined Contributions (NDCs), would reduce warming to between 2.5°C (4.5°F) to 2.9°C (5.22°F) above preindustrial levels by 2100.
- These higher temperatures would have a far greater chance of triggering tipping points in the climate system; those include the loss of parts (or all) of the Greenland and West Antarctic ice sheets and potential shutdown of a vital ocean current.
- The report finds that Paris targets could only be met by fully implementing both conditional and unconditional parts of emissions pledges to date, as well as translating global net zero goals into action.
- Currently, net zero pledges cover about 80% of emissions, but most are hollow, without implementing mechanisms to back them up.
- Using current NDCs, the emissions gap in 2030 would be 14 billion tons of CO2 for the 2°C target, and 22 billion tons for the 1.5-degree goal, the report shows. The latter figure is larger than the estimated 2022 annual emissions of the U.S. and China combined.
- To meet the 2°C target, the report finds that emissions would need to decline by 28% by 2030 compared with current policy scenarios, and by 42% to stand a chance of meeting the 1.5-degree goal. In contrast, global emissions rose by 1.2% between 2021-2022, per the report.
- The chances, however, of holding warming to 1.5 degrees without any overshoot period would be extremely low, the report shows, pegging it at just 14% in the most optimistic scenarios.
- The analysis finds that the emissions gap estimates are likely to be underestimated because the least-cost pathways to meet the Paris targets assume that stringent reductions began in 2020. Instead, they have continued to increase.
Between the lines: The amounts of warming seen in this series have become somewhat less dire over the years, while climate solutions have proliferated.
- The 2016 edition, for example, had a projected warming of up to 3.4°C (6.12°F) under a current-policies trajectory.
- While warming projections have come down somewhat, the world is running out of time and space in the carbon budget to ensure Paris targets are met.
- In addition, scientists have been seeing more significant climate impacts, from heat waves to wildfires, which are happening with lower amounts of global warming.
The intrigue: The report takes a cautious approach regarding the potential over-reliance on a risky technological fix to the emissions gap.
- It says any delays in policies to strengthen emissions reductions would boost the dependence on carbon dioxide removal, including through new means currently in their infancy.
What they're saying: "At a time of doubt, division and distrust we need the response to the Global Stocktake to restore credibility in climate action," said U.N. Secretary-General António Guterres. "Leaders can't kick the can any further. We're out of road."
- "There is no person or economy left on the planet untouched by climate change, so we need to stop setting unwanted records on greenhouse gas emissions, global temperature highs and extreme weather," said Inger Andersen, executive director of the UN Environment Program, in a statement.