Emission generated by the international merchant fleet has been suggested to represent a significant contribution to the global anthropogenic emissions. To analyze the impacts of these emissions, we present detailed model studies of the changes in atmospheric composition of pollutants and greenhouse compounds due to emissions from cargo and passenger ships in international trade. Global emission inventories of NOx, SO2, CO, CO2, and volatile organic compounds (VOC) are developed by a bottom‐up approach combining ship‐type specific engine emission modeling, oil cargo VOC vapor modeling, alternative global distribution methods, and ship operation data. Calculated bunker fuel consumption is found in agreement with international sales statistics. The Automated Mutual‐assistance Vessel Rescue system (AMVER) data set is found to best reflect the distributions of cargo ships in international trade. A method based on the relative reporting frequency weighted by the ship size for each vessel type is recommended. We have exploited this modeled ship emissions inventory to estimate perturbations of the global distribution of ozone, methane, sulfate, and nitrogen compounds using a global 3‐D chemical transport model with interactive ozone and sulfate chemistry. Ozone perturbations are highly nonlinear, being most efficient in regions of low background pollution. Different data sets (e.g., AMVER, The Comprehensive Ocean‐Atmosphere Data Set (COADS)) lead to highly different regional perturbations. A maximum ozone perturbation of approximately 12 ppbv is obtained in the North Atlantic and in the North Pacific during summer months. Global average sulfate loading increases with 2.9%, while the increase is significantly larger over parts of western Europe (up to 8%). In contrast to the AMVER data, the COADS data give particularly large enhancements over the North Atlantic. Ship emissions reduce methane lifetime by approximately 5%. CO2 and O3 give positive radiative forcing (RF), and CH4 and sulfate give negative forcing. The total RF is small (0.01–0.02 W/m2) and connected with large uncertainties. Increase in acidification is 3–10% in certain coastal areas. The approach presented here is clearly useful for characterizing the present impact of ship emission and will be valuable for assessing the potential effect of various emission‐control options.

[1] Shipping activity has increased considerably over the last century and currently represents a significant contribution to the global emissions of pollutants and greenhouse gases. Despite this, information about the historical development of fuel consumption and emissions is generally limited, with little data published pre-1950 and large deviations reported for estimates covering the last 3 decades. To better understand the historical development in ship emissions and the uncertainties associated with the estimates, we present fuel-based CO 2 and SO 2 emission inventories from 1925 up to 2002 and activity-based estimates from 1970 up to 2000. The global CO 2 emissions from ships in 1925 have been estimated to 229 Tg (CO 2 ), growing to about 634 Tg (CO 2 ) in 2002. The corresponding SO 2 emissions are about 2.5 Tg (SO 2 ) and 8.5 Tg (SO 2 ), respectively. Our activity-based estimates of fuel consumption from 1970 to 2000, covering all oceangoing civil ships above or equal to 100 gross tonnage (GT), are lower compared to previous activity-based studies. We have applied a more detailed model approach, which includes variation in the demand for sea transport, as well as operational and technological changes of the past. This study concludes that the main reason for the large deviations found in reported inventories is the applied number of days at sea. Moreover, our modeling indicates that the ship size and the degree of utilization of the fleet, combined with the shift to diesel engines, have been the major factors determining yearly fuel consumption. Interestingly, the model results from around 1973 suggest that the fleet growth is not necessarily followed by increased fuel consumption, as technical and operational characteristics have changed. Results from this study indicate that reported sales over the last 3 decades seems not to be significantly underreported as previous simplified activity-based studies have suggested. The results confirm our previously reported modeling estimates for year 2000. Previous activity-based studies have not considered ships less than 100 GT (e.g., today some 1.3 million fishing vessels), and we suggest that this fleet could account for an important part of the total fuel consumption ($10%).Citation: Endresen, Ø., E. Sørgård, H. L. Behrens, P. O. Brett, and I. S. A. Isaksen (2007), A historical reconstruction of ships' fuel consumption and emissions,

We have complemented existing global sea transportation emission inventories with new regional emission data sets and scenarios for ship traffic and coastal activity in 2015. Emission inventories for 2000 and 2015 are used in a global Chemical Transport Model (CTM) to quantify environmental atmospheric impacts with particular focus on the Arctic region. Although we assume that ship emissions continue to increase from 2000 to 2015, reductions are assumed for some chemical components and regions because of implementation of new regulations. Current ship traffic (2000) is estimated to contribute significantly to coastal pollution. Norwegian coastal ship traffic is responsible for more than 1/3 and 1/6 of the Norwegian NOx and SO2 emissions, respectively. For these short‐lived components the impact of Norwegian coastal emissions is regionally important. For most components the international ship transportation outside coastal waters dominates the effects. Ship emissions increase wet deposition in Scandinavia with 30–50% for nitrate and 10–25% for sulfate. In general, coastal regions with prevailing onshore winds show substantial increases in deposition of acid components. Maximum surface increase in ozone is in excess of 10 ppbv. Column ozone increases are also significant. Assuming no changes in nonshipping emissions, scenarios for shipping activities in 2015 lead to more than 20% increase in NO2 from 2000 to 2015 in some coastal areas. Ozone increases are in general small. Wet deposition of acidic species increases up to 10% in areas where current critical loads are exceeded. Regulations limiting the sulfur content in the fuel in the North Sea and English Channel will be an efficient measure to reduce sulfate deposition in nearby coastal regions. The expected oil and gas transport by ships from Norway and northwest Russia, sea transport along the Northern Sea Route and new Norwegian coastal gas power plants will have a significant regional effect by increases of acid deposition in north Scandinavia and the Kola Peninsula. Augmented levels of particles in the Arctic are calculated, and thus the contribution from ship traffic to phenomena like Arctic haze could be increasing.

No abstract

This article presents results from the Commission of the European Communities (CEC) project "Safety of Shipping in Coastal Waters" (SAFECO). The project was performed by ten European partners during the period 1995-1998. The principal aim of the SAFECO project was to determine the influences that could increase the safety of shipping in coastal waters by analyzing the underlying factors contributing to the marine accident risk level. The work reported here focuses on the Marine Accident Risk Calculation System (MARCS) that was further developed during the SAFECO project. This paper presents the methods used by MARCS, as well as data and results from a "demonstration of concept" case study covering the North Sea area. The estimated accident frequencies (number of accidents per year) were compared with historical accident data, to demonstrate the validity of the modeling approach. Reasonable (within a factor of 5) to good (within a factor of 2) agreement between calculated accident frequencies and observed accident statistics was generally obtained. However, significant discrepancies were identified for some ship types and accident categories. The risk model has particular problems with estimating the accident frequency for drift grounding in general and powered grounding for ferries. It was concluded that these discrepancies are related to uncertainties in several areas, specifically in the risk model algorithms, the traffic data, the error and failure probability data, and the historical accident statistics.