206
L. Johansson et al.
according to current legislation. The approach described in this paper can be applied
in larger scale, for example to cover European coastlines in the future.
32.1 Introduction
In contrast to commercial marine vessel traffic, small boat activities in the Baltic Sea
cannot be estimated based on the Automatic Identification System (AIS), because
AIS-equipment is not mandatory for boats. Since little or no information exists on
the activities of boats, their contribution has all but been ignored in environmental
impact studies of shipping. In many Baltic Sea countries, like in Finland for example,
data of fuel sold to recreational boats are not collected and incomplete statistics
exists for the number of boats and their locations in the Baltic Sea coastline. This
makes assessments of small boat fuel consumption and emissions very challenging.
This is in contrast with large marine vessels, for which our earlier work with Ship
Traffic Emission Assessment Model (STEAM) [1, 2, 3, 4] can be applied. In this
paper we present an approach which is applicable for small boats, which are not well
presented in STEAM emission inventories. This approach is called the Boat Emission
and Activity siMulator (BEAM) and it extends the capabilities of the waterborne
emission modeling to the part of traffic which is not visible in AIS. In short: STEAM
is for ships, BEAM is for boats.
32.2 Materials and Methods
The data available for small boat emission modeling varies by country. Countries
like Finland do not keep track of boat marina locations or boat counts in the Baltic
Sea coastline. A national boat registry is available, but it does not distinguish boats
used on the coast of the Baltic Sea and inland waters. Further, no statistics exist for
fuel sold to small boats or emissions and their spatio-temporal distribution.
Temporal distribution of boating activity
While AIS-data cannot be used to produce reliable pleasure boat activity data, AISdata does contain enough small pleasure crafts for the estimation of temporal variation
of activities. The resulting temporal variation of activities can be used across the
Baltic Sea for all pleasure craft. It should be noted the ships that are not IMOregistered but still sending AIS-messages can also be pilot vessels, Search and Rescue
(SAR) craft, small tugs and service vessels. Thus, leisure boats need to be filtered
out from the AIS data.
AIS data from Helcom from period 2014-2016 and the STEAM model was used
in this analysis. First, a collection of boats was isolated from the AIS-data. These
were filtered out from the overall AIS data using criteria like (a) Active only during
1st May–30th September, (b) travel distances not exceeding a selected threshold
L. Johansson et al.
according to current legislation. The approach described in this paper can be applied
in larger scale, for example to cover European coastlines in the future.
32.1 Introduction
In contrast to commercial marine vessel traffic, small boat activities in the Baltic Sea
cannot be estimated based on the Automatic Identification System (AIS), because
AIS-equipment is not mandatory for boats. Since little or no information exists on
the activities of boats, their contribution has all but been ignored in environmental
impact studies of shipping. In many Baltic Sea countries, like in Finland for example,
data of fuel sold to recreational boats are not collected and incomplete statistics
exists for the number of boats and their locations in the Baltic Sea coastline. This
makes assessments of small boat fuel consumption and emissions very challenging.
This is in contrast with large marine vessels, for which our earlier work with Ship
Traffic Emission Assessment Model (STEAM) [1, 2, 3, 4] can be applied. In this
paper we present an approach which is applicable for small boats, which are not well
presented in STEAM emission inventories. This approach is called the Boat Emission
and Activity siMulator (BEAM) and it extends the capabilities of the waterborne
emission modeling to the part of traffic which is not visible in AIS. In short: STEAM
is for ships, BEAM is for boats.
32.2 Materials and Methods
The data available for small boat emission modeling varies by country. Countries
like Finland do not keep track of boat marina locations or boat counts in the Baltic
Sea coastline. A national boat registry is available, but it does not distinguish boats
used on the coast of the Baltic Sea and inland waters. Further, no statistics exist for
fuel sold to small boats or emissions and their spatio-temporal distribution.
Temporal distribution of boating activity
While AIS-data cannot be used to produce reliable pleasure boat activity data, AISdata does contain enough small pleasure crafts for the estimation of temporal variation
of activities. The resulting temporal variation of activities can be used across the
Baltic Sea for all pleasure craft. It should be noted the ships that are not IMOregistered but still sending AIS-messages can also be pilot vessels, Search and Rescue
(SAR) craft, small tugs and service vessels. Thus, leisure boats need to be filtered
out from the AIS data.
AIS data from Helcom from period 2014-2016 and the STEAM model was used
in this analysis. First, a collection of boats was isolated from the AIS-data. These
were filtered out from the overall AIS data using criteria like (a) Active only during
1st May–30th September, (b) travel distances not exceeding a selected threshold