197
1 INTRODUCTION
1.1 The background of the ILMERI research project
Climate change is significantly impacting weather
conditions in southern Finland [1], particularly during
the winter months [2]. Rising temperatures have led to
a decrease in the annual ice cover in the Baltic Sea [3].
Whereas in the past, the Gulf of Finland was
completely covered in ice during a typical winter,
nowadays, during many winters, the sea is almost ice-
free, with only archipelago areas on the Finnish coast
or locations at the end of the Gulf of Finland remaining
ice-covered [4]. The complete freezing of Lake Ladoga
is no longer guaranteed, which also contributes to the
local climate in south-eastern Finland [5]. Generally,
the ice-free sea facilitates winter navigation, but in
practice, the change in conditions is not
straightforward [6]. On the polar front, weather
conditions can vary significantly, leading to the
periodical continuation of cold winters and/or cold
periods during winters [7]. For winter navigation, this
creates conditions that can be difficult to predict. The
sea ice field, which is formed during freezing
temperatures, may not remain stable when
temperatures rise again [8]. Dynamic moving and
packing ice can pose significant challenges for ships
operating in ice fields or for maritime safety
equipment, such as buoys or other navigation marks
[9]. Conversely, during the winter months, the
The Impact of Climate Change on Maritime Transport:
A Review of the Situation in the Kymenlaakso Region
E. Altarriba
South-Eastern Finland University of Applied Sciences, Kotka, Finland
ABSTRACT: In the context of international trade logistics, Finland is an island. Due to the significant reduction
in trade with Russia following the war in Ukraine, maritime transport has become the predominant mode of
transportation for exports and imports, accounting for approximately 95%. The Port of Hamina-Kotka, located in
south-eastern Finland, is the primary freight port in the region and plays a crucial role in the maritime logistics
of the heavy industry in eastern Finland. The consequences of climate change are being felt acutely in the area,
especially during the winter months. Rising temperatures are leading to a decline in winter sea ice cover annually,
exerting a substantial influence on winter weather conditions in the region. However, the variability of weather
conditions, which is expected to continue in the future, poses an additional challenge. The ILMERI project
(Impacts of Climate Change on Maritime Transport, implemented between March 1, 2025, and February 28, 2026),
conducted by the South-Eastern Finland University of Applied Sciences and funded by the European Regional
Development Fund, studies the effects of changes in conditions caused by climate change on maritime transport
in the Kymenlaakso region. This article presents a summary of the baseline situation, including a review of the
region’s fairway system, marine transportation infrastructure, typical cargo types transported, and available
climate data. This is significant because fairway and port solutions represent long-term investments, and any
recommendations must be based on reliable data to prevent both over and under-preparedness for future
challenges.
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 19
Number 1
March 2025
DOI: 10.12716/1001.19.01.23
198
presence of non-frozen sea can heighten the risk of
heavy snowfall in coastal regions, thereby presenting
challenges to both port operations and safe navigation
[10-12]. Similarly, the rapid melting of snow increases
the likelihood of winter floods. The summer season has
also been impacted by climate change. Prolonged heat
waves in Central European countries have led to
significant health concerns, particularly among high-
risk populations. These problems may also become
more common in Finland if summer heat waves
become more frequent and last longer.
The ILMERI research project (Impacts of Climate
Change on Maritime Transport), conducted by the
South-Eastern Finland University of Applied Sciences
and funded by the European Regional Development
Fund, aims to map the potential impacts of climate
change on maritime transport in the Kymenlaakso
region. The project will be implemented between
March 1, 2025, and February 28, 2026, in close
cooperation with stakeholders. The project supports
the implementation of the Climate Resilient
Kymenlaakso Adaptation Plan [13]. Preparing for
climate change at the infrastructure level is a long-term
effort, and defining the appropriate level of
preparedness is challenging. Over-preparedness
generates unnecessary costs, while under-
preparedness can be critically damaging. The project
aims to support the definition of a proper level of
preparedness.
1.2 Fairway channels
The maritime area of the Kymenlaakso region contains
numerous fairways, some of which are suitable for
boating, as well as significant deep-water channels that
connect the lanes of the Gulf of Finland to the various
harbours of the Port of Hamina-Kotka [14]. The port
has several berths; Mussalo and Hamina harbours are
the main loading areas. However, there is also
significant activity in Hietanen and Sunila, and the port
includes parts of Kantasatama and Halla. The various
harbours of the port are responsible for distinct types
of port operations, as well as cargo handling facilities
and infrastructure. Consequently, the size and type of
vessels berthing in these harbours also vary
significantly.
The Orrengrund-Kotka channel [15] is comprised of
several fairways that provide access to both Mussalo
Harbor and the inner harbour areas of Kotka, including
Kantasatama, Hietanen, Sunila, and Halla. Many
sections of the channel are lit, including the route from
Orrengrund to Kotka. However, the channel also
contains unlit sections mainly concentrated in the
Mussalo and inner harbour areas. The channel is
unsheltered against southerly winds as far as the
entrance of Mussalo harbour, and strong winds and
rough seas can hamper navigation. However, no
official traffic recommendations have been established
regarding wind, ice conditions, or visibility. The
fairway channel is illustrated in Figure 1.
Figure 1. Orrengrund-Kotka channel (IDs: 5605, 5535, 5690,
5570, 5615, 5590, 5532, 5533, 5385). Data source: Fairway card,
Finnish Transport Infrastructure Agency [15]
The Mussalo channel is an illuminated route that
[16], in contrast to the Orrengrund-Kotka channel [15],
provides direct navigation to the harbour of Mussalo
from the lanes of the Gulf of Finland. The channel is
fully lighted, except for certain sections within the
harbour basin. The outer part of the channel is in the
open sea and is unsheltered against east, south, and
south-west winds, and strong winds and rough seas
may hamper navigation. As in the Orrengrund-Kotka
case, no official traffic recommendations regarding
wind, ice conditions, or visibility have been established
in this channel. The Mussalo channel is illustrated in
Figure 2.
Figure 2. Mussalo channel (IDs: 5510, 5532) Data source:
Fairway card, Finnish Transport Infrastructure Agency [16]
The Hamina Channel [17] connects the open sea
lanes to the harbour of Hamina. The fairway is
equipped with leading lights and beacons, and it
includes one meeting and overtaking prohibition area.
The outer parts of the channel are open sea areas that
are unsheltered against south-west, south, and east
winds. Navigation may be hampered by the rough seas
or strong winds. The inner parts of the channel are
sheltered by islands. A visibility recommendation has
been established for the fairway. Visibility should be at
least 0.5 nautical miles. The fairway alignment is
illustrated in Figure 3.
199
Figure 3. Hamina channel (IDs: 5507) Data source: Fairway
card, Finnish Transport Infrastructure Agency [17]
1.3 Port of HaminaKotka
The Port of HaminaKotka is a versatile general port
comprised of several harbours, of which the main
harbours are the ports of Hamina and Mussalo [14].
Container traffic is concentrated in Mussalo, while
bulk cargo and RoRo traffic is distributed among all
harbours of the port except Sunila. The old
Kantasatama harbour, located in the centre of Kotka, is
being converted into a passenger-only terminal.
Detailed information regarding all harbours and their
respective cargo handling capacity is included in
Table 1.
Table 1. Port traffic statistics
Harbour
Cargo type
Halla
Dry and breakbulk, LoLo, RoRo
Hamina*
Dry and liquid bulk, gas, RoRo, StoRo, LoLo,
project shipments
Hietanen
RoRo and dry bulk
Kantasatama
RoRo, cruise passenger traffic
Mussalo*
Containers, dry and liquid bulk, RoRo, StoRo,
project shipments
Sunila
Mainly exported pulp
* Most important harbors
** Finngas
*** Sunila Ltd
Data: Port of HaminaKotka statistics [14]
Table 2. Port traffic statistics 2020-2024, import and export
Year
Export (t)
Import (t)
Vessel traffic
2024
8,607,239
4,537,454
2,181
2023
9,411,216
4,706,592
2,265
2022
11,279,507
4,985,805
2,575
2021
11,055,407
3,518,840
2,345
2020
11,426,842
3,419,894
2,420
Data: Port of HaminaKotka statistics [14]
Table 3. Port traffic statistics 2024, cargo types
Variable
Export (t)
Import (t)
Dry bulk
2,137,411
429,959
Liquid bulk
188,441
1,035,857
Sawn goods
1,577,904
-
Wood pulp
1,474,007
-
Raw wood
-
2,211,068
Paper
2,114,671
-
Other goods
811,992
407,317
General cargo
302,813
453,2
Data: Port of HaminaKotka statistics [14]
As shown in Table 2, the port’s export and import
volumes, as well as vessel traffic, are listed for the
period from 2020 to 2024. Cargo volumes have
traditionally been weighted towards exports, although
between 2022 and 2024, this difference has narrowed
considerably (see statistics in [14]). The distribution of
exports and imports for different types of cargo is
shown in Table 3 for 2024. The most significant export
product categories include dry pulp, sawmill products,
wood pulp, and paper. Among the imported products,
liquid bulk and raw wood stand out as the most
notable.
2 OBSERVATION METHODS
2.1 Sea level
The Baltic Sea does not have periodic tides, but
significant variations in sea level are still observed [18].
The primary factor contributing to these variations is
the prevailing weather conditions. The weather-
affected currents through the Danish Straits influence
the total volume of water in the Baltic Sea [19, 20].
Regionally, wind-driven currents move water from
one sea area to another, a phenomenon particularly
pronounced in geographical areas such as the Gulf of
Finland. When winds cease, water masses settle,
forming seiche waves [21]. Water level fluctuations
caused by winds can be significant [18]. For instance, in
the Kymenlaakso region, the recorded maximum and
minimum water levels differ by over three meters [22].
Water levels are also influenced by regional air
pressure, and extreme water levels frequently result
from a combination of various factors.
This article utilizes data collected by the Finnish
Meteorological Institute’s mareograph station located
on Pitäjänsaari Island in Hamina City (position 60.563°
N, 27.179° E). The available data is recorded between
January 1, 1980, and December 31, 2024. The recording
interval is as follows: 1 hour from January 1, 1980, to
April 16, 2013, 15 minutes from April 17, 2017, to
December 31, 2017, and 1 minute from 2018 onward.
The water level is reported in the N2000 system.
2.2 Temperature and precipitation
Temperature measurement is significantly affected by
the micro-location of the meter. In urban areas,
measurements often provide higher-than-average
values, especially on sunny summer days [23]. On the
other hand, measurements in the archipelago are
highly impacted by the sea water temperature,
particularly for small islands [24]. Additionally,
precipitation measurements exhibit significant
regional variations, and coastal areas are affected by
distinct weather patterns [25]. For instance, while
precipitation is recorded at the coast, the sky might be
clear in the outer archipelago.
This paper utilizes data on average temperature
and precipitation collected by the Finnish
Meteorological Institute [22]. The data is presented as a
grid data set, delineating a 10 x 10 km grid within the
City of Kotka. The data are examined on an annual
basis and separated according to the following
seasonal categories: winter (December, January,
February), spring (March, April, May), summer (June,
July, August), and autumn (September, October,
November). Climate change has a particularly
200
significant impact on the region during the warmer
winter months. It is, therefore, essential to closely
observe the progression of these changes.
2.3 Sea ice
The extent of sea ice in the Baltic Sea has shown
significant year-to-year variation [4]. In addition to the
amount of ice, the challenges posed by sea ice to
maritime transport are influenced by various factors,
including the duration and thickness of the ice period,
which are strongly influenced by winter weather
conditions [8]. Even a reduction in the quantity of ice
does not necessarily guarantee a more favourable
winter for maritime transport. The presence of moving
ice fields and packed ice can pose significant challenges
for vessels with a lower ice-class [9, 26]. The formation
of ice ridges typically occurs in areas where moving ice
meets a fixed ice field that is positioned against the
coast or an archipelago [27]. These regions are
commonly encountered in the outer archipelago,
though instances of ice jams are not uncommon in the
central Gulf of Finland. In addition, the structure of the
ice significantly impacts its strength and integrity [28].
Snow serves as an insulator, meaning that the amount
of snowfall directly impacts the formation and strength
of sea ice.
This paper examines sea ice data from the entire
Baltic Sea as well as the coast of the Kymenlaakso
region [22]. The size of the winter ice field in the Baltic
Sea is a reliable indicator of the overall ice cover level.
For the Kymenlaakso coast, the sea ice cover situation
is analysed using data from the Haapasaari
observation station. This monitoring station provides
essential insights into the sea ice conditions in the outer
archipelago. In contrast, the inner archipelago typically
experiences longer periods of ice presence, though ice
conditions tend to be more stable.
2.4 Wind
In terms of average wind speeds, the effects of climate
change in the Kymenlaakso region are not entirely
clear. While it is anticipated that global wind speeds
will increase, with a corresponding intensification of
extreme weather events, future changes in average
wind speeds in the Kymenlaakso region are not fully
elucidated at this time [29, 30]. This paper utilized data
from the Haapasaari measuring station (operated by
the Finnish Meteorological Institute) from January 1,
2004, to December 31, 2024, with an interval of one
hour. Additionally, average wind speeds from October
1 to March 31 are considered separately. This is done
because annual warming is influenced by the colder
half of the year.
3 RESULTS
3.1 Sea level observations
Sea level observations are listed in Table 4. The results
are obtained from the mareograph of Hamina
Pitäjänsaari, operated by the Finnish Meteorological
Institute [22]. For the periods 1980-1989, 1990-1999, and
2000-2010, minimum and maximum values, mean,
median, and standard deviation have been considered
on a decade-by-decade basis. For the period 2011-2024,
the same variables are expressed annually as well. The
range between the lowest and highest recorded values
is approximately 3 meters. However, the mean and
median values indicate that sea level conditions are, on
average, more tranquil. The deviations also suggest
that the outlier values are atypical, as anticipated. The
reference level is N2000.
Table 4. Sea level (mm, N2000), Pitäjänsaari mareograph
Variable
Min.
Max.
Mean
Med.
Dev.
1980-1989
-748
1834
259
232
282
1990-1999
-826
1747
232
219
273
2000-2010
-946
2131
229
205
265
2011
-490
1699
277
230
269
2012
-703
1519
278
260
243
2013
-956
1472
220
161
265
2014
-633
913
110
84
223
2015
-355
1739
335
311
286
2016
-545
1040
188
163
251
2017
-712
1120
312
302
236
2018
-568
1440
142
123
251
2019
-523
1260
241
242
222
2020
-296
1520
376
337
267
2021
-504
1656
208
192
215
2022
-754
1343
263
248
245
2023
-477
1653
266
265
240
2024
-573
1460
249
244
243
Data: Finnish Meteorological Institute [22]
3.2 Temperature and precipitation observations
As shown in Table 5, the mean values of temperature
and precipitation data from 1991 to 2020 are presented
in a grid-based format for Kotka City [22]. The average
annual temperature is 5.9°C. However, due to the
proximity of the sea, the average winter temperature
remains at -3.7°C. A tendency towards increased
precipitation during the autumn months is observed.
However, the discrepancy between winter and
summer rainfall is not significant. Spring experiences
the lowest precipitation, but the seasonal differences
are relatively negligible.
Table 5. Temperature and precipitation 1991-2020 averages
Variable
Temp. (°C)
Precip. (mm)
Year
5.9
606
Winter
-3.7
142
Spring
3.7
99
Summer
16.5
171
Autumn
7.0
194
Data: Finnish Meteorological Institute [22]
Figures 4-8 illustrate temperature and precipitation
anomalies in the years 1962-2024 compared to the 1991-
2020 mean values [22]. As illustrated in Figure 4, there
has been a notable increase in the average temperature
trend of nearly 3°C over the past 60 years. The changes
have been particularly evident in the average
temperatures during winter (Figure 5) and spring
(Figure 6). For precipitation, the trend has been
increasing for winter precipitation, though there is
greater variability for spring rainfall levels. The
summer season is expected to see an increase in
temperature levels (Figure 7), although not as
significant as the trends observed, e.g., in the winter
months. In addition, the past few years have
experienced warmer-than-average conditions. No
substantial changes have been observed in summer
precipitation. For the autumn season (Figure 8),
201
precipitation variability is greater, but there has also
been an observed trend of increasing temperatures.
Figure 4. Annual temperature and precipitation levels in
Kotka (1962-2024). Data: Finnish Meteorological Institute [22]
Figure 5. Winter temperature and precipitation levels in
Kotka (1962-2024). Data: Finnish Meteorological Institute [22]
Figure 6. Spring temperature and precipitation levels in
Kotka (1962-2024). Data: Finnish Meteorological Institute [22]
Figure 7. Summer temperature and precipitation levels in
Kotka (1962-2024). Data: Finnish Meteorological Institute [22]
Figure 8. Autumn temperature and precipitation levels in
Kotka (1962-2024). Data: Finnish Meteorological Institute [22]
3.3 Sea ice observations
Quantifying sea ice in absolute terms is challenging
due to the dynamic nature of the ice field, which is
subject to variation in the number of warm and cold
periods and windiness during winters. Table 6 shows
the sea ice cover of the Haapasaari area for the period
1961-1990 [22]. The table lists dates of first freezing,
formation of permanent ice cover, end of permanent ice
cover, and final disappearance of sea ice, including
earliest, median, and latest dates. A similar data set is
shown in Table 7 for the period 1991-2020 [22]. A
comparison of median dates reveals the impact of
global warming on prevailing ice conditions, as
evidenced by a shortening of the average ice season.
However, significant variations in ice formation are
observed between years, as evidenced by the wide
range of earliest and latest dates (Tables 6 and 7).
Table 6. Sea ice cover in Haapasaari region, 1961-1990.
Variable
Earliest
Median
Latest
First freezing
7 Dec
5 Jan
15 Feb
Formation of permanent ice cover
18 Dec
13 Jan
15 Feb
End of permanent ice cover
10 Jan
22 Apr
12 May
Final disappearance of ice
12 Jan
29 Apr
16 May
Data source: Finnish Meteorological Institute [22]
Table 7. Sea ice cover in Haapasaari region, 1991-2020.
Variable
Earliest
Median
Latest
First freezing
6 Dec
18 Jan
9 Feb
Formation of permanent ice cover
7 Dec
27 Jan
21 Feb
End of permanent ice cover
4 Feb
14 Apr
12 May
Final disappearance of ice
17 Feb
20 Apr
15 May
Data source: Finnish Meteorological Institute [22]
As shown in Table 8, which presents statistics on the
coverage of sea ice in the Baltic Sea for the winters of
2003-2024, there has been significant variation in ice
coverage [22]. During the observed period, the ice
coverage was more than 8 times higher at its maximum
(winter 2010-2011) compared to the mildest winter
(winter 2019-2020). This provides insight into the
variation, but as Tables 6 and 7 illustrate, regional
differences can also be substantial.
202
Table 8. Sea ice cover in the Baltic Sea
Variable
Max (km
2
)
2023-2024
135,000
2022-2023
81,000
2021-2022
93,000
2020-2021
127,000
2019-2020
37,000
2018-2019
88,000
2017-2018
170,000
2016-2017
88,000
2015-2016
110,000
2014-2015
51,000
2013-2014
100,000
2012-2013
177,000
2011-2012
179,000
2010-2011
309,000
2009-2010
244,000
2008-2009
110,000
2007-2008
49,000
2006-2007
140,000
2005-2006
211,000
2004-2005
178,000
2003-2004
153,000
Data source: Finnish Meteorological Institute [22]
3.4 Wind observations
Table 9 presents the average wind data from the
Haapasaari weather station [22]. The table includes the
mean, median, and standard deviation values of the
average wind speed for the period 2004-2024, along
with annual categorized values. The analysis reveals
no significant deviations in wind speeds during the
considered timeframe. For the period 2019-2024, the
mean values are slightly above the 20-year average,
though there have been several years in the 2010s when
the mean was slightly below the average. In terms of
median values, the results are stable, with no major
changes in standard deviation.
Table 9. Average annual wind observations in the
Haapasaari region
Variable
Mean
Med.
Dev.
2004-2024
6.6
6.2
3.2
2004
6.2
6.0
2.9
2005
6.6
6.2
3.3
2006
6.3
6.0
3.2
2007
6.6
6.2
3.3
2008
6.9
6.6
3.4
2009
6.2
5.9
3.2
2010
5.9
5.6
3.1
2011
6.4
6.1
3.4
2012
6.5
6.3
3.2
2013
6.2
5.8
3.0
2014
5.9
5.5
3.0
2015
6.5
6.2
3.1
2016
6.2
5.8
3.1
2017
6.6
6.3
3.1
2018
6.5
6.0
3.3
2019
7.0
6.8
3.2
2020
7.5
7.3
3.4
2021
7.1
6.7
3.3
2022
6.9
6.7
3.1
2023
7.0
6.6
3.3
2024
6.9
6.4
3.4
Data source: Finnish Meteorological Institute [22]
As shown in Table 10, the corresponding variables
are listed for the annual periods of 1 October to 31
March [22]. Periods under consideration extend longer
than the standard winter season (December, January,
February) to assess potential variations in windiness
during the cold season. In comparison to the results
presented in Table 9, the average wind speeds are
slightly elevated. The trends observed in windy years
remain consistent with those presented in Table 9.
Otherwise, the results are in line with expectations.
Table 10. Average winter wind observations in the
Haapasaari region
Variable
Mean
Med.
Dev.
1.10.2004-31.3.2005
7.2
7.0
3.4
1.10.2005-31.3.2006
6.9
6.8
3.3
1.10.2006-31.3.2007
7.5
7.3
3.5
1.10.2007-31.3.2008
7.8
7.8
3.6
1.10.2008-31.3.2009
7.4
7.0
3.5
1.10.2009-31.3.2010
6.1
5.9
3.4
1.10.2010-31.3.2011
6.9
6.6
3.3
1.10.2011-31.3.2012
7.6
7.3
3.6
1.10.2012-31.3.2013
6.7
6.3
3.2
1.10.2013-31.3.2014
7.2
7.0
3.2
1.10.2014-31.3.2015
7.3
7.3
3.1
1.10.2015-31.3.2016
7.0
6.6
3.3
1.10.2016-31.3.2017
7.1
7.0
3.3
1.10.2017-31.3.2018
7.5
7.1
3.4
1.10.2018-31.3.2019
8.1
8.1
3.3
1.10.2019-31.3.2020
8.5
8.5
3.5
1.10.2020-31.3.2021
7.9
7.8
3.3
1.10.2021-31.3.2022
8.3
8.2
3.4
1.10.2022-31.3.2023
7.7
7.7
3.3
1.10.2023-31.3.2024
7.4
6.9
3.5
Data source: Finnish Meteorological Institute [22]
4 DISCUSSION
Sea water level fluctuations pose challenges for
shipping [18,20,21]. While commercial ports and
fairways are designed to withstand significant
fluctuations in sea level when determining berth
heights, fairway depths, and the installation of
navigational safety equipment [15-17], the potential for
increased extreme situations can present challenges
[18]. In the Baltic Sea, where prevailing wind
conditions are the primary driver of water level
fluctuations, extreme weather events may lead to
increased occurrences of floods or exceptionally low
water levels, even in the absence of a significant change
in average annual wind speed. In terms of safety
equipment, floating buoys have proven to be more
resilient to sea water level fluctuations. However, there
may be challenges associated with sea marks installed
in archipelago fairways. The most significant
challenges often arise from combinations of
exceptional water levels coinciding with heavy rain,
storms, waves, or moving ice fields [1,3,8]. Regarding
prevailing sea water levels, it is important to note that
fluctuations can be categorized as either momentary or
gradual. Due to global warming, sea levels are rising
worldwide, increasing the likelihood that new
extremes will be reached. However, in the Baltic Sea,
post-glacial land uplift is constraining this basement
rise in sea level. It is important to note that small boat
ports may be more susceptible to fluctuations in sea
water levels compared to larger commercial ports. In
smaller ports, the available amount of reserve water is
often limited, and high water levels can easily lead to
flooding in fixed piers or submerged boat mooring
buoys. Conversely, the economic repercussions of
restricting operations at larger commercial ports would
be substantial.
The milder winters in Finnish latitudes will
generally facilitate winter navigation in terms of ice
203
conditions (except for dynamically moving ice) [8] but
will also result in darker winters in terms of daylight,
as the amount of light-reflecting snow and ice will
decrease, but the amount of sunlight in the winter
season will not increase [29,30]. Visibility is also
impacted by prevailing weather conditions. Cloudy
skies, foggy weather, and drizzly conditions can all
contribute to reduced luminosity, even if the total
amount of rainfall remains consistent. During the
winter solstice, the day is short in the Kymenlaakso
region, with a duration of only 5 hours and 43 minutes.
The presence of darkness and twilight can impede the
efficiency of all activities and often necessitate the wide
use of artificial light, which can be viewed as an
escalation in light pollution as well. Smart beacon or
buoy technology offers the technical capability to
monitor local weather conditions (e.g., visibility,
rainfall, fog, currents) on a micro level. However, it will
take time for this technology to become widespread
[31]. This provides a certain degree of assistance in
anticipating conditions, particularly in narrow
fairways. Heavy rain, snow, or wave conditions can
impair marine radar performance, necessitating the use
of rain and wave clutters. Filtering out heavy rainfall
on the radar display can also result in the erasure of
smaller echoes, such as sea marks, rocks, or smaller
vessels moving in the area.
Over the past decade, the Safety Investigation
Authority of Finland has investigated two incidents in
eastern Uusimaa, located near the Kymenlaakso
region, both of which involved direct weather-related
impacts. The collision between the pilot boat and the
missile boat was narrowly avoided [32]. The Safety
Investigation Authority determined that several
factors contributed to the dangerous situation,
including the darkness, the diffuse light from the oil
refinery’s spotlights in the background, and the Navy’s
desire to operate inconspicuously at times. In the same
area, a pilot boat capsized a year earlier, resulting in the
deaths of two individuals. This incident also occurred
at night, when a south-western wind generated a wave
approximately 2 meters high but of particularly sharp
character. This wave, in combination with the ship's
manoeuvres and its effect on the prevailing wave
system, resulted in the pilot boat capsizing [33].
Although the wave’s height did not exceed typical
parameters for the region and the time of year, limited
visibility may have been a contributing factor to the
situation, making rescue operations more difficult.
There have been several reported incidents in low
visibility conditions in Finland. The report M2019-03
[34] analyses the incident involving the ROPAX vessel
and a road ferry in the Archipelago Sea, where a
collision was narrowly avoided. The incident occurred
during daylight, but the November day was grey,
cloudy, and rainy, with visibility limited to 3-4 miles.
Report C4/1997 [35] analyses a collision between the
road ferry and the RORO ship in foggy conditions,
report C3/2004M [36] a collision between the Navy all-
weather craft and the archipelago ferry in icy
conditions and fog, and report C7/2005M [37]
investigates a collision between the road ferry and the
minesweeping equipment at night. The accident was
caused by the ferry master’s reduced alertness and
fatigue. A thematic study on fatigue [38] in bridge
work reveals that this type of work is primarily passive
surveillance, where critical actions must be taken in a
time-sensitive manner. Long periods of darkness and
grey weather do not alleviate fatiguing conditions.
Climate change can have direct or indirect impacts
on economic activities. Generally, economic risks are
associated with the functioning and characteristics of
oil and fuel markets, as well as environmental policies
[39-41]. In the past, the risk factor was primarily
associated with an increase in fuel prices in the context
of a shift to non-fossil fuels. However, in the present
day, the situation is much more complex. New
regulations, such as FuelEU Maritime [42] and the EU
ETS [43], mandate a gradual transition by merchant
fleets exceeding 5000 GT to lower greenhouse gas
(GHG) intensity fuel and propulsion solutions. The
IMO has also set ambitious targets to make maritime
transport carbon neutral in the future. This will have a
significant impact on the fuel market, which may
complicate price forecasting and affect investment
profitability. This could result in political pressure that
may lead to a reconsideration of previously adopted
solutions, creating further uncertainty in the market.
This kind of development has been observed in the
context of US environmental politics. Conversely, the
obligation to distribute biofuels (in road transport) in
Finland has been politically adjusted lower, as the price
of fuels went up in 2022 due to the impact of Russia's
invasion of Ukraine.
Weather conditions can impact different ship types
in considerably different ways [44-46]. As such, the
operational capabilities of different vessels are
contingent upon the prevailing wave conditions. In
situations where wind speeds are particularly high,
port manoeuvring under these conditions becomes
considerably challenging, particularly for ships with
large wind surface areas or those otherwise sensitive to
wind. Consequently, the vessel's type and operational
speed determine the necessity for reserve water under
the keel. Ships with a strong ice classification (e.g., 1A
or 1A Super) possess the capability to function
autonomously, even in relatively challenging ice
conditions [47]. Regulations pertaining to the ice
classification of vessels permitted to navigate to
regional ports during winter have been enacted to
ensure the safety of maritime operations in ice-covered
waters. In principle, these policies can be continued in
the future as well. However, if the number of vessels
classified as higher ice-class vessels decreases due to
energy efficiency requirements, such a policy could
theoretically result in substantial losses in foreign trade
if the winter ice proves to be exceptionally severe [48].
This principle similarly applies to investment decisions
regarding icebreaking fleet modernization. What is the
optimal investment strategy when winters are
predominantly mild? However, if a severe and cold
winter occurs, are we prepared to face the resulting
challenges?
ACKNOWLEDGEMENTS
The research discussed in this paper was carried out as part
of the research project “Impacts of climate change on
maritime transport” (ILMERI, A81073), funded by the
European Regional Development Fund (ERDF). The
Regional Council of Kymenlaakso is thanked for organizing
the funding.
204
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