Third IMO Greenhouse Gas Study 2014

Annex 1 159
Ship class Capacity bin Capacity units
Vehicle 0–3,999 vehicles
4,000–+
Miscellaneous – fishing All sizes
gt
Miscellaneous – other All sizes gt
Offshore All sizes gt
Service – other All sizes gt
Service – tug All sizes gt
Yacht All sizes gt
It should be noted that because the basic method in Section 1.2 performs all calculations on a “per ship”
basis and minimizes the use of average assumptions applied across populations of ships, there is a lesser need
than in the Second IMO GHG Study 2009 for the bins used to be representative of technical or operational
homogeneity.
Estimating ship activity over the course of a year using AIS data
The first stage in the bottom up model is the pre-processor and multi-AIS merger phase where the ship activity
of a ship throughout the year is generated from AIS data. The following section discusses the source data used
in this phase and the individual steps involved.
Sources and spatial and temporal coverage
The deployment of the AIS technology has only been enforced in the last 10 years (IMO, 2002) and in
the intervening years its coverage has greatly increased. Due to its creation as a collision detection system,
receivers were largely deployed around port facilities and in traffic-dense areas resulting in a lack of cover on
the open ocean. In recent years, with the emergence of its use in other applications (e.g. security of ships in
piracy zones), there has been greater demand for deployment of receivers globally. As a result, spatio-temporal
coverage of the technology is ever increasing. The consortium has a high level of confidence in this coverage
for the latter years of the study (i.e. 2011 and 2012) but decreasing confidence for previous years. Although
S-AIS, which provides open ocean coverage, is available from 2010, it has only limited coverage for that year,
but improves greatly in 2011 and 2012. The different AIS sources used in this study are outlined in Table 5.
The quality provided by this coverage is discussed in greater detail in Annex 5.
Table 5 – Number of processed messages (in millions) in 2007–2012 for each terrestrial
and satellite data sets. EMSA LRIT data were used for QA/QC
of the bottom-up emissions estimation only
Kystverket exactEarth
Marine
Traffic
Receiver
type
Area Global Global Global,
coastal
EMSA (AIS)
IHS
Civic
exchange
Starcrest
compiled
EMSA
(LRIT)
Satellite Satellite Terrestrial Terrestrial Terrestrial Terrestrial Terrestrial Satellite
EU, coastal
Global,
coastal
Hong Kong
New York
Area
2012 162.3 519.0 1 731.0 1 308.0 – 1.4 – 9.9
2011 142.0 159.0 1 769.0 1 100.0 – 1.3 – 9.9
2010 – 34.4 334.5 893.7 – – 1.5 22.3
2009 – – – – 96.0 – – 7.0
2008 – – – – 73.0 – – –
2007 – – – – 4.7 – – –
Global