Management of vessel-borne biological invasions: policy, economic, and technology assessment
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
Global shipping activities account for 90% of global trade and play an important role in the world economy and welfare, but vessels generate different negative environmental impacts meanwhile, by air emissions, greenhouse gas emissions (GHG), and species invasion. The four studies in this work aim to inform related policymaking at international and regional levels to reduce the negative impacts from international shipping. ☐ The first study examines the container vessel diversion pattern to trans-Arctic shipping routes and GHG emission abatement potential under climate change and ice retreat in the Arctic area. Literature shows inconsistent conclusions on the economic feasibility of the trans-Arctic routes, which motivates this work to examine the potential general diversion patterns of the global shipping traffic. While we find some trans-Arctic routes are economically feasible, the diversion potential of trans-Arctic routes may be overestimated. The sample in this work contains 522,691 shipping moves, and only 83 moves would reduce distance, and 45 would save sailing time through the Arctic; however, 20 moves would reduce shipping cost. Though few diversions may happen, we find that 20 economically feasible trans-Arctic diversions reduce GHG emissions. Their average fuel consumption reduction through the Arctic is 264 metric tons (MT) (reduced by 26%); the range is 125-328 MT. The average CO2e emission is 767 MT (reduced by 24%); the range is 359-954 MT. Most of these voyages are between North America and East Asia. These results inform ship operators a possible operating way to achieve the GHG abatement goal by making a diversion to the trans-Arctic routes for voyages between certain geographical areas. ☐ The second work starts to examine the policies to manage ballast water discharge to decease aquatic species invasion from the perspective of the technology. Ballast water treatment systems (BWTS) are the technology to comply with the ballast water regulations but generate great compliance costs, which may increase the shipping cost. Therefore, to balance the effectiveness and cost of ballast water treatment, this work evaluates technological strategies that include conventional vessel-based and alternative barge-based technologies. We also propose a potential policy scenario under which California makes efforts to provide additional protection from ballast discharge invasion risk. We construct a vessel-versus-barge compliance cost framework to examine the available technological strategies. The results show that the stringency of the regulations matters the technology selection a lot. If a single global standard is a weak standard, then adopting vessel-based compliant technology is less costly than centralized barge-based compliance. This work considers these findings to apply generally beyond the California context. Specifically, if some region or all regions adopt standards different from current global standards (i.e., stricter), barge-based systems can be less costly than retrofitting world fleets. ☐ The third work continues to global ballast water management and further balance the compliance cost and potential negative impacts on the economy and global trade. We employ an integrated shipping cost and global economic modeling method to examine the impacts of ballast management regulations on bilateral trade, national economies, and shipping patterns. Given the potential need for more stringent regulation at regional hotspots of species invasions, this work considers two ballast water treatment policy scenarios: implementation of current international regulations, and a possible stricter regional regulation that targets ships traveling to and from the United States while other vessels continue to face current standards. We find that ballast water management compliance costs under both scenarios lead to modest negative impacts on international trade and national economies overall. However, stricter regulations applied to U.S. ports are expected to have large negative impacts on the bilateral trade of several specific commodities for a few countries. Trade diversion causes decreased U.S. imports of some products, leading to minor economic welfare losses. ☐ The fourth work further moves the ballast water regulations forward with integrated analysis with a risk-policy-economic-technology nexus. The work uses a ballast water-borne biological invasion risk assessment model based on a higher-order-network. (1) By quantifying the ballast water treatment efficacy of BWTS under the IMO and stricter global standards, the work reveals that stricter regulation is needed to further reduce invasion risks. Given the revealed uneven distribution risks at different ports, the work finds that regional regulations are needed to target high-risk ports. (2) By cluster analysis, the work reveals both intra- and inter-cluster species introduction pathways and identifies “hub ports” connecting several clusters. Targeting such hub ports is the key to break down the inter-cluster connection not only can protect high-risk ports, but also reduce worldwide risks with lower costs by changing the inter-cluster species introduction pattern. (3) Then the work combines a technology cost model to find the least costly way to compliance different “regional stricter regulatory scenarios” since the new policy may choose different numbers of ports to strictly regulate. By varying the number of higher-risk ports selected to do stricter regulations, the model simulates 4257 policy cases. The work finds the vessel-based method is least costly under the IMO regulations under every policy case, while the port-based method becomes important to lower the compliance cost for stricter regulations. The identifies the threshold of the number of ports regulated more strictly for compliance technology selection: when the number of high-risk ports is smaller than 2882, the port-based method at high-risk ports combining the vessel-based method is the least costly strategy; when the number is larger than 2882, the port-based method at all world ports is least costly. This implies the geopolitical shifts in global ballast water management since the IMO is the agency to regulate ships while it cannot make requirements for ports.
Description
Keywords
Ballast water, Biological invasion, Cost-effectiveness analysis, GTAP, International shipping, Marine policy