Black carbon (BC) is either a climate change menace or an overblown and unproven problem of little consequence according to some in the maritime sector.
Mitigating the effects of BC on the Arctic is seen by the IMO and the UN as critical with its amplified potential for global warming of the Polar ice caps and the expected catastrophic consequences to global weather systems as a result.
It is for this reason that the IMO is now considering the use of Polar fuels to protect what is seen by most scientists as a critical region for climate change mitigation.
That is not the view of all in the maritime sector, an industry key to the regional prosperity and a major emitter of BC, with some owners and their representatives and some of the UN’s IMO member states dissenting.
Nevertheless, IMO secretary general Arsenio Dominguez is keen to articulate the UN’s support for cleaner oceans and its support towards reducing aerosols including BC over the past 15 years.
“We operate in the oceans, we regulate the ships, but we’re also very much aware of the impact shipping has on the oceans,” said Dominguez, adding, IMO is keen, “to demonstrate the steps we’re taking in decarbonisation, which of course is also part of the work that we’re carrying out on black carbon, IMO is very conscious of the need for environmental protection, including plastic pollution, underwater radiated noise and invasive species.”
Maritime’s debate on the Polar Code, the IMO’s regional regulation, applies to The IMO Arctic, a subset of the larger geographic Arctic, which is generally accepted as the area north of 59degs north. The ‘IMO Arctic’ is a smaller region and refers to ships operating in waters north of 60°N latitude.
A study by the influential International Council of Clean Transportation (ICCT), published in May this year, reported BC emissions within the IMO Arctic increased from 193 tonnes in 2015 to 413 tonnes in in 2021. In the geographic Arctic BC emissions had nearly doubled by 2021 to 1.5 kilo-tonnes.
The 12th session of the IMO’s Pollution Prevention Response (PPR) subcommittee, an offshoot of the Marine Environmental Protection Committee, met in January this year with Friends of the Earth International leading a group of environmental NGO’s, including WWF, calling for the IMO to make the use of distillate fuel to be mandatory in the Arctic.
MGO is the preferred fuel of most observers, at least for the immediate future, because it reduces the levels of particulates the most, at least until a clean alternative is developed, according to Elena Tracy senior advisor for sustainable development at the World Wildlife Fund (WWF)’s Global Arctic Programme, which has observer status at the IMO.
“Switching to distillate fuels in the Arctic region will reduce black carbon emissions by 50-80%,” said Tracy who agrees that the MGO is a fossil fuel but argues that this could be a “quick fix.”
Quoting the ICCT Tracy added: “While also installing diesel particulate filters will further reduce BC emissions by 90% and more, depending on the type of engine.”
The original proposal was to reduce BC by mandating the use of the less polluting MGO in the Arctic region. However, a second environmental issue was raised by IMO member states, including Norway, who were concerned with the impact of an oil spill in cold Arctic waters.
Following the 1989 Exxon Valdez tanker spill in cold Alaskan waters the effects of that accident -the 28th worst at that time- can still be seen today, because HFO solidifies in cold waters, preventing effective clean-up operations.
As a result, PPR12 agreed to look at various sub-types of MGO, two in particular DMA and DMZ, with pour points of at least 0degs and will report back to PPR13 next year. Allowing for more efficient remediation in terms of the effects on delicate ecosystems and feeding grounds for endangered species.
it is also relevant that shipping is not the only source, or even the major source of BC in the Polar region, but as the ice melts new navigable pathways for large ships are opening shorter routes between Asia, Europe and North America, with the expectation that shipping’s emissions will increase.
Europe has a critical role to play in the Arctic region with 2,315 of the 3,171 vessels operating in the geographic Arctic heading to or from EU ports, and therefore reported emissions to the European monitor, report and verify emissions tracking system.
EU vessels of more than 5,000gt contributed 44% of BC in the Arctic. With residual fuels due to be phased out by 2029 from the Arctic region, and no guarantee that key states such as Russia and the US will comply with IMO regulations, the EU could have a decisive role to play in the reduction of regional BC.
Moreover, with the introduction of emission control areas stretching from Canada to Norway is aimed at controlling poisonous sulphur dioxide emissions through scrubber technology is seen by some as a fix for both BC and sulphur emissions.
Scrubbers filter sulphur dioxide from exhaust gases and are used with heavy fuel oil (HFO), with owners recouping investment on the technology, by saving on using the more expensive distillate MGO.
Mike Kaczmarek, a former Carnival Cruise VP, now chairman of the Clean Shipping Alliance (CSA), which promotes the use of scrubber technology, argues that studies on the BC issue are essentially theoretical in nature without scientific testing of the theories.
“It is a theory, I don’t think there’s been any observation of this [BC accelerating ice melts] taking place in the Arctic. So, it remains hypothetical,” said Kaczmarek.
CSA said the only credible studies [of BC] are ones that use data, “The studies that we’re aware of, which we think are the most credible, are the ones where they actually have data and not just literature reviews,” said Kaczmarek, “Our understanding is that a scrubber also reduces between 60 and 90% of the particulates, including black carbon.”
CSA’s views on BC are not shared by classification society DNV’s VP and director for environment, maritime Eirik Nyhus who said the UN’s International Panel on Climate Change (IPCC) recognises that BC does have an impact and that the effects are increased by the fact that BC absorbs heat and then radiates that warmth, which is making the Polar ice melt faster.
Nyhus concedes that there are, “uncertainties inherent with respect to aerosols,” however, he adds there is no reason to doubt the science produced by the IPCC and IMO, which has been working on the issue of BC for 15 years, “I think my reading of the science is that it [the effects of BC] are pretty clear.”
Again, Nyhus concedes that quantifying the effects in precise detail may be challenging and that causes some uncertainty, but that does not mean that there is no impact.
