Global warming is on track to cross the 1.5°C threshold by the end of this decade, increasing the risk of more severe climate impacts, including extreme weather events, the United Nations Environment Programme (UNEP) said in a report released on Wednesday.
The report cited by Hindustan Times, titled ‘Limiting Overshoot’, also stressed that crossing the threshold does not mean efforts to bring temperatures back down should be abandoned. It said the world can still work towards the goals set under the 2015 Paris Agreement, which seeks to keep long-term global temperature rise below 1.5°C.
Current trends point to 1.5°C crossing
According to the UNEP assessment, human-induced global warming is already approaching 1.4°C above pre-industrial levels. Global temperatures have been rising at around 0.25°C per decade, putting the 1.5°C mark within reach before the decade ends.
“Under current policies, median projected global warming reaches around 2.6°C by 2100 (range 1.9–3.6°C). Even under one of UNEP’s most optimistic scenarios, which assumes implementation of all NDCs [Nationally Determined Contributions] and long-term net zero targets, central global warming estimates peak at around 1.8°C (range 1.7–2.2°C),” the report says.
It adds: “Extrapolating current trends, global warming may reach 1.5°C around the end of this decade.”
Every fraction of a degree matters
UNEP said climate risks would become more severe with every additional fraction of a degree and each year temperatures remain elevated.
“Anticipated impacts include intensified extreme weather, ecosystem loss, and submersion of Small Island Developing States and low-lying coastal cities. Severe damage to human health, food security, water supplies, nature, cities, infrastructure, and economies is expected,” the report says.
The assessment also points to a growing risk of irreversible tipping points as temperatures rise. These include the destabilisation of major ice sheets, degradation of the Amazon rainforest and disruption of the Atlantic Meridional Overturning Circulation, a major system of ocean currents that helps regulate the climate.
UNEP calls for faster climate action
The report identifies an overshoot, peak and decline pathway as the best remaining option for limiting how far and how long global temperatures remain above 1.5°C. Under an optimistic scenario involving full implementation of current national climate plans and additional net-zero commitments, warming could peak at around 1.8°C.
“Reductions in methane and other short-lived climate pollutants are particularly important in the immediate term. Enhancing adaptive and mitigation capacity requires strong political will, urgent multilateral action, effective policies and finance — with equity, justice and differentiated responsibilities serving as guiding principles.”
UNEP executive director Inger Andersen said the consequences of warming are already becoming visible.
“Across the globe, extreme heatwaves are already proving that climate impacts will strike faster, hit harder, and last longer - costing more lives and causing deeper disruption,” she said. “Now is the time we must double down on climate action. We can – and must – get on the right path. By cutting greenhouse gas emissions, strengthening resilience and adaptation, and ensuring exceedance of 1.5°C is as small and short as possible.”
UN Secretary-General Antőnio Guterres also warned about the consequences of rising temperatures, saying, “This is a warning of what lies ahead. We must make the overshoot above 1.5 degrees as small and short as possible. That demands an overshoot of ambition.”