Global Temperatures Will Inevitably Exceed 1.5 Degrees... Greenhouse Gas Emissions Must Fall 45% by 2035 [Reading Science]

UNEP: Temperatures Projected to Rise 2.8 Degrees Celsius by Century’s End if Current Policies Remain
Experts: "Oceans and Ice Sheets May Not Recover Even if Temperatures Fall Again"

Exceeding the international community’s goal of limiting global average temperature rise to 1.5 degrees Celsius above preindustrial levels has become inevitable. If current climate policies remain in place, temperatures are projected to rise by as much as 2.8 degrees Celsius by the end of this century. An analysis found that even if temperatures temporarily exceed 1.5 degrees, global greenhouse gas emissions would need to fall 45% by 2035 from 2025 levels to bring warming back down by 2100.

The Greenland ice sheet and surrounding terrain, captured by a NASA Earth-ob observing satellite. A glacier flows between the massive ice sheet on the right and rocky terrain on the left, with blue lakes visible in various locations. Climate experts warned that even if global average temperatures fall again, the ice sheet loss already underway may not be easily reversed. Courtesy of NASA.

According to the 2026 Emissions Gap Report released on October 21 (local time) by the United Nations Environment Programme (UNEP), global average temperatures are projected to reach 2.8 degrees Celsius above preindustrial levels by the end of this century if countries maintain their current climate policies. Even if countries fully meet their submitted Nationally Determined Contributions (NDCs) and continue making similar levels of emissions cuts, the rise would still reach 2.6 degrees. Temperatures would fall to 2.1 degrees only if countries also achieve additional net-zero targets.

The report stressed that, as it has become difficult to avoid temperatures exceeding 1.5 degrees, the magnitude and duration of the overshoot must be minimized. To limit the rise to 1.7–1.8 degrees by mid-century and bring it back below 1.5 degrees by 2100, global greenhouse gas emissions must be cut from 2025 levels by 18% by 2030, 45% by 2035, and 69% by 2040. This scenario gives about a 50% chance of returning to below 1.5 degrees by 2100. However, the analysis found that even if all countries meet their NDCs, emissions cuts by 2035 would amount to only 11–15%.

Global greenhouse gas emissions have shown signs of plateauing, but it is too early to conclude that they have begun to decline. Total emissions last year were similar to the previous year, but carbon dioxide emissions from the fossil fuel sector actually increased. It remains difficult to say definitively that emissions have peaked.

Even as Temperatures Fall, Earth May Not Return to Its Previous State

Climate experts in South Korea said it is important to focus not only on the extent of temperature rise but also on irreversible changes caused by the warming process.

Jongseong Kwon, a professor in the Department of Earth and Environmental Sciences at Seoul National University, said on October 22 through the Science Media Center Korea (SMCK), “Even at the same 1.5 degrees, Earth during the warming process may be in a completely different state from Earth that has returned to 1.5 degrees after experiencing higher temperatures.”

The cover of the United Nations Environment Programme's (UNEP) 2026 Emissions Gap Report, "The Point of Return." UNEP officially released the report on the 21st, projecting that if current climate policies remain in place, the global average temperature will rise 2.8 degrees Celsius above pre-industrial levels by the end of this century. Provided by UNEP.

Kwon explained that changes in ocean circulation, ice sheet loss, and abrupt ecosystem changes may not be easily reversed even if temperatures fall. He said that, alongside cutting greenhouse gas emissions, South Korea needs to make precise forecasts of extreme weather, water resources, and ecosystem changes on the Korean Peninsula and in East Asia, and develop adaptation strategies.

Experts also said South Korea’s emissions reduction policies need improvement. Jung Soojong, a professor at Seoul National University’s Graduate School of Environmental Studies, pointed out that national greenhouse gas emissions are primarily calculated using statistics and emission factors, limiting the ability to determine actual emissions in detail by region and industrial facility. He said a system is needed to verify emissions by combining satellite and ground-based observations and to transparently report the results of emissions reductions.

Cho Chunho, former director of the National Institute of Meteorological Sciences, said climate policies had achieved some results, noting that temperature rise was projected at about 4 degrees based on policies in place in 2010. However, he said, “Climate action so far has helped avert the worst-case future, but it remains insufficient to reduce the risks enough.”

Oh Jaeho, CEO of Nano Weather and an emeritus professor at Pukyong National University, pointed to the limitations of uniform emissions reduction policies that do not take regional climates and energy consumption structures into account. “Carbon neutrality must be achieved through real greenhouse gas emissions reductions verified in local communities, not through declarations or plans,” he stressed.

This content was produced with the assistance of AI translation services.