The International Maritime Organization (IMO) released the
long-awaited 575-page final report for its Fourth IMO Greenhouse Gas Study.
Coming six years after the third report, the results are viewed as a critical
scorecard measuring the success of the shipping industry towards the goals of
reducing greenhouse gas emissions. The IMO is not commenting on the study at
this stage, noting that its Marine Environment Protection Committee is being
asked to consider and approve the study, but those in the industry as well as
government and environmental groups are all anxiously reviewing the results and
will begin providing their independent analysis.
The key finding of the report indicates that the shipping
industry’s greenhouse gas emission increased by nearly 10 percent between 2012
and 2018. The international consortium of research institutes and universities
that prepared the report also forecasts that shipping emissions will increase
by up to 50 percent until 2050 relative to 2018 despite further efficiency
gains, as transport demand is expected to continue to grow.
“The report will provide the IMO with a factual basis for
the negotiations on measures to address greenhouse gas emissions from
shipping,” says Jasper Faber who was project manager working at CE Delft that
lead the consortium. “It has again improved on the methods and presentation of
the previous Greenhouse Gas studies. We are proud to have assembled a truly
global consortium bringing together some of the best experts in the field.”
In total, the report finds that GHG emissions including
carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), for the total
shipping industry (international, domestic and fishing) increased 9.6 percent
from 977 million tonnes in 2012 to 1,076 million tonnes in 2018. Looking
specifically at the CO2 component of the emissions, they found a similar rate
of increase from 962 million tonnes in 2012 to 1,056 million tonnes of CO2
emissions in 2018. As a result of this, they estimated that shipping’s share of
global emissions increased slightly from 2.76 percent in 2012 to 2.89 percent
in 2018.
The fourth report also introduces several new elements, more
details and analysis. “This study represents a significant step forward in
estimating emissions inventories, and for the first time uses a fully
IPCC-aligned approach to estimate international shipping emissions,” said Elena
Hauerhof, of UMAS who was the leader of the inventory work. “The study has also
significantly advanced the accuracy of AIS based estimations for any ship, and
evidences this by undertaking a detailed validation against fuel consumption
and other key parameters reported in EU MRV for over 9000 ships”
Due to developments in data and inventory methods, this
study is able to produce greenhouse gas inventories that distinguish domestic
shipping from international emissions on a voyage basis as well as a new
voyage-based allocation of international shipping. While the data shows an
increase in CO2 emissions from international shipping on the voyage-based
allocation it also reveals a lower growth rate than total shipping emissions
and an approximately constant share of global CO2 emissions over this period.
Using the vessel-based allocation of international shipping CO2 emissions
increased more than eight percent but again slower than total shipping.
Another important area that the study looks at is the carbon
intensity of shipping. It is reported to have improved by about 11 percent, but
the growth in activity was larger than the efficiency gains according to the
study. Shuang Zhang of Dalian Maritime University, leader of the work on carbon
intensity commented, “Carbon intensity of international shipping is a new
addition to the IMO GHG Studies, in response to the Initial IMO GHG strategy.
The estimates provided by this report have clearly shown where we are on the
way towards low-carbon shipping.” The analysis, however, notes that
improvements in the carbon intensity of international shipping have not
followed a linear pathway and more than half the improvements were achieved
before 2012. The pace of carbon intensity reduction has slowed since 2015 the
report says.
For the first time, the study also includes estimates for
other elements such as back carbon which the report points to as having
consequences both for climate and human health. Known as a super pollutant the
data shows a 12 percent increase in black carbon emissions as well as more than
a 150 percent jump in methane emissions. The report points out that total LNG
use in international shipping increased by less than a third. The explanation
for the difference in growth rates for fuel consumption and methane emissions
is associated with a shift in the mix of machinery being used across the fleet
during this period.
Looking forward the report provides a range of long-term
economic and energy scenarios creating a projection that emissions will
increase from about 90 percent of 2008 emissions in 2018 to 90-130 percent of
2008 emissions by 2050. The authors expect that emissions in 2020 and 2021 will
be significantly lower based on the impact of COVID-19, but note depending on
the recovery trajectory, overall the impact of COVID-19 is likely to be smaller
than the uncertainty range of the presented scenarios.
The IMO expects to submit the report to the committee in the
fall for its consideration and approval. In the meantime, the complete document
is available for download by registering on the IMO’s website.