The shipping industry has quietly gone without a climate plan — until now

The global shipping industry has agreed to its first greenhouse gas reduction plan at the London headquarters of the International Maritime Organisation (IMO) Friday, having reached a compromise that would see the sector halve its 2008 emissions by the middle of the century.

Fraught climate talks at the IMO this week have seen national governments attempting to thrash out a deal over how ambitious the sector should be in reducing its climate impact.

Shipping is the last major global industry without a comprehensive climate plan, after the aviation sector agreed to a carbon offsetting scheme in 2016. Its emissions are not covered under the Paris Agreement.

The IMO formally adopted an interim climate strategy with the backing of more than 170 national governments, after many opponents to an emissions cap relented during the course of the week-long negotiations.

Although not nearly as ambitious as many delegates and green campaigners had hoped, the compromise reached on the climate plan has been widely welcomed by industry figures and policymakers.

Hilda Heine, president of the Marshall Islands — one of a key group of climate-vulnerable nations campaigning for an ambitious shipping emissions goal — said the IMO had today "made history."

"While it may not be enough to give my country the certainty it wanted, it makes it clear that international shipping will now urgently reduce emissions and play its part in giving my country a pathway to survival," she said in a statement. "This deal helps make every country a little safer, but even with a landmark sectoral cap and clear targets to reduce emissions consistent with the Paris Agreement, we will need to improve it over time in line with the latest science."

As well as an outright emissions cap, the strategy sets a carbon intensity reduction target — the amount of emissions relative to each tonne of shipping cargo — of at least 40 percent by 2030, rising to 70 percent by 2050. It also includes plans for a review of energy efficiency design requirements for ships, and to develop incentives to boost research on low carbon shipping technologies and fuels.

However, the final target to cut emissions by 50 percent by 2050, against 2008 levels, is much weaker than that sought by IMO delegations such as the European Union, which had called for a 70 to 100 percent cut in emissions. The initial strategy also only sets out a general ambition for the sector, with no formal obligation for parties to meet the emissions goal. The final strategy will be released in 2023, the IMO promised.

Experts warn that a 50 percent target is not nearly enough to keep the sector in line with the 1.5 degrees Celsius or even 2 degrees Celsius temperature ambitions set out in the Paris Agreement, which would require a goal close to net zero emissions from shipping by 2050.

IMO studies have estimated that greenhouse gases from international shipping accounted for around 2.2 percent of the world's entire man-made emissions in 2012, and that these emissions are likely to grow between 50 percent and 250 percent by the middle of the century as trade increases.

The EU therefore had threatened to enforce its own emissions targets on ships entering the region's waters by 2023 unless the IMO takes strong enough action on its own, but a number of nations — such as Saudi Arabia, Brazil and India — were resistant, fearing that an emissions cap adversely could affect trade.

Having agreed on the overall ambition for the shipping industry, the IMO will set about on implementing the targets, which like U.N.-wide climate talks is likely to see a division of responsibility between richer and poorer nations.