Even if the high-income G20 countries, including the US, the UK, Australia and Germany, were to reduce their domestic emissions to zero by 2030, they would still fall significantly short of their fair-share benchmarks for emissions reduction, according to a new paper published by Oxfam International.

The paper by the global non-governmental organisation evaluates the fairness and ambition of national greenhouse gas reduction targets, known as Nationally Determined Contributions (NDCs), of the G20 countries, using three distinct approaches. These approaches were employed to gauge the strength of the conclusions drawn. If all approaches arrived at similar results, it would suggest that the conclusions were robust.

The findings reveal that the G20, collectively as well as the most high-income countries of the bloc individually, are failing to meet the necessary levels of ambition required to limit the global temperature rise to 1.5 degrees Celsius.

The gap between the collective NDCs of G20 and the fairness or ambition benchmarks outlined by the three approaches ranges from 2.8 to 3.9 tons of carbon dioxide equivalent per capita by 2030.

This translates to an alarming excess of emissions in 2030, with the G20 countries alone accounting for a surplus of 14.1 to 20.2 billion tons of CO2 equivalent. It underscores the urgent need for the G20 countries to significantly intensify their climate mitigation efforts, the paper read.

Delving further into the disparities among the G20 countries, the paper notes that the high-income nations of the grouping bear the primary responsibility for historic emissions and possess the technological and financial resources to address the climate crisis. But they are falling far short of their fair-share benchmarks, with emissions levels still exceeding what would be equitable by a large margin.

For example, the United States and Australia, both high-income countries, would need to enhance their 2030 NDC emission reduction targets by 240 per cent and 170 per cent respectively to align with the fair-share benchmarks. Similarly, Germany and the United Kingdom would need to increase their targets by 160 per cent and 124 per cent respectively.

The paper underscores that even if the high-income countries reduce their domestic emissions to zero by 2030, they will still not meet their fair-share benchmarks. These nations would need to provide substantial climate finance, technology transfers and support to other countries to bridge the emissions gap.

The middle-income G20 countries, while having lower historic responsibilities and fewer financial resources, are also found to fall short in achieving their fair share of global emissions targets, the paper says. This highlights the need for these countries to adopt more ambitious emissions reduction targets, consistent with the fairness benchmarks.

These findings are crucial as the Global Stocktake, set to be finalised by the end of 2023 at COP28, aims to guide countries in enhancing the ambition of their climate action.

The persistent failure of the G20 countries to meet their ambitious and fair emissions reduction targets exacerbates the climate crisis, disproportionately affecting low-income communities and marginalised groups, Oxfam said, adding that the consequences of climate inaction are not only devastating but deeply unjust.

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