## 2 Current Status of Ocean-Going Ship Weather Routing Services  
This section reviews the current status, focusing primarily on the national service provider (NMC) due to data availability and its central role, while also acknowledging other key players in the Chinese market. The world's major shipping routes are highly interconnected, linking key ports across continents. As shown in Figure 1, these routes form the arteries of international trade. The fundamental objective of ship weather routing services is to provide vessels with accurate weather forecasts during navigation. This ensures maritime safety while minimizing operational costs and carbon emissions, contributing to the development of green shipping. Globally, the primary users of ship weather routing services typically include shipowners and charterers (i.e., lessees of vessels). The specific services provided vary depending on contractual agreements and operational needs. Under the framework of a charter party, particular emphasis is placed on analyzing ship sailing data and assessing ship performance throughout the voyage. At the end of the voyage, a comprehensive audit report is compiled, incorporating the vessel's trajectory and prevailing weather conditions. This report serves as essential documentation for resolving potential speed claims, shipping disputes, or contractual disagreements related to the charter party. Most of the world's leading ocean-going weather routing companies are privately owned enterprises based abroad, such as Weather News Inc. (WNI) from Chiba, Japan, StormGeo (Bergen, Norway), Weather Routing Inc. (Glens Falls, NY, USA), and True North Marine (Montreal, QC, Canada) [25]. These companies have a long-established history and have developed comprehensive business systems and technological infrastructures through business expansion and mergers and acquisitions. As a result, they dominate more than 90% of the global weather routing service market. As a leading enterprise in international weather routing services, WNI, headquartered in Japan, serves as a representative example for comparison due to its market leadership and publicly available service information, though a direct comparison of proprietary algorithms is not possible. It has a history spanning over 50 years since its establishment. WNI offers a wide range of services, including  
* Ship Route Optimization: Providing safe and economical route optimization based on vessel characteristics and weather forecasts, including the fastest arrival route, lowest fuel consumption route, fixed-time arrival route, and the safest route. * Pre-arrival Services: Advising vessels on optimal route planning 3-5 days before arrival to efficiently manage fuel consumption and scheduling. * Vessel Performance Monitoring: Conducting real-time analysis of vessel performance and generating interim audit reports. Upon voyage completion, a comprehensive performance assessment is provided, including time loss and fuel consumption analysis. In case of disputes, these reports serve as supporting evidence for claims and legal proceedings. * Carbon Emission Monitoring: Utilizing ship and fleet data to calculate CO2 emissions and assess the Energy Efficiency Operational Index (EEOI) for the entire fleet. WNI acquires extensive meteorological and oceanographic observation data through collaborations with public institutions, private enterprises, and its clients/members. To further enhance its data capabilities, WNI has developed and launched multiple small observation satellites to support its weather routing services [35]. In 2006, the company established the Global Sea Ice Center to monitor sea ice dynamics and support Arctic weather routing. Additionally, WNI has advanced numerical weather forecasting through refined interpolation and interpretation techniques, AI-driven forecasting systems, and a suite of weather routing tools and software, thereby strengthening its weather routing services.