GLOBAL warming could slow the rise in some Commonwealth countries’ gross domestic product (GDP) by up to 75 per cent by 2100, unless temperature increases can be checked, the latest research suggests.

A report, The Climate Cost to the Commonwealth, for the international development charity Christian Aid, says that, even if the rise is reduced from the current 2.7ºC to the target of 1.5ºC set in the Paris Agreement of 2015, the loss for some nations would be about 40 per cent.

The study, by Marina Andrijevic, an economist at the International Institute for Applied Systems Analysis, in Vienna, shows that the GDP of all nations will grow over time, but climate change will cut the rate of increase. The worst affected country would be Nigeria. Under current climate policies, it would face a reduction of 75.3 per cent by the end of the century. Even in a 1.5ºC scenario, the drop would be 42.6 per cent.

Close behind are Pakistan (73.1 per cent at current levels; 40.1% at 1.5C), and India (71.5 per cent and 39.3 per cent).

Paradoxically, one of the Commonwealth’s worst polluters, Canada, would see an expansion of more than 120 per cent, as the increased temperature would enable more land to be brought into production. The UK would see a rise of more than 20 per cent. The study used data from 40 of the 56 Commonwealth countries.

Ms Andrijevic said that the figures were only a conservative estimate, as they were based solely on the impact of rising temperatures, not the effect of extreme weather events blamed on climate change. “This analysis shows the huge strain that climate change will be on the economic development of the Commonwealth,” she said.

“The countries assessed here make up more than a quarter of the world’s population, and span every populated continent. Many of these countries face a number of challenges, and the climate crisis poses a major threat to their ability to sustainably develop.”

Per person, the UK emits 64 times more carbon than the fellow Commonwealth nation Malawi. Canada emits more than 179 times more and Australia, 188 times. In fact, the per capita emissions of carbon dioxide by the Commonwealth’s richest four countries — UK, Australia, Canada and New Zealand — is 41.1 tons, which is 23 times larger than the ten least emitting per capita Commonwealth countries combined (1.78 tons).

The CEO of Christian Aid, Patrick Watt, said: “These findings underline the deep injustice at the heart of the climate crisis. The Commonwealth countries that contribute least to the problem stand to be worst affected by rising average temperatures. By the same token, the historic carbon emissions of a handful of the richest Commonwealth members are causing escalating damage to millions of the world’s poorest people.”

He said that the report showed the urgent need to get the “loss-and-damage” fund agreed at COP27 up and running (News, 25 November 2022). Money from richer nations would be used to fund measures by poorer countries to counteract the effects of climate change. “The Commonwealth, as a body that brings together some of the heaviest climate polluters and the most climate-vulnerable countries, has a genuine opportunity to model a just and sustainable response to the climate crisis, with rich nations contributing their fair share,” Mr Watt said.

“And we need to see the major polluters taking immediate action to cut their emissions, to put us on a collective path to a sustainable future.”

In a foreword to the report, Vanessa Nakate, a Ugandan climate activist, said: “The Commonwealth captures the severe inequality of climate change. Within its ranks are some of the world’s biggest polluters per capita: Australia with its coal industry, Canada with its tar sands. The average citizen of those countries is responsible for as much carbon as 100 people from my country, Uganda.

“Nowhere should the case for action to drastically cut emissions and increase financial support be more clear than among this group of nations. The leaders of Australia, Canada, New Zealand, and the UK like to speak warm words about their Commonwealth ‘family’, but, so far, their action to address the climate crisis has fallen tragically short.

“It need not be this way. The Commonwealth is a group of countries that can demonstrate what true climate co-operation can look like.”