operations management, a multifaceted discipline that serves as the backbone of organizations by ensuring efficiency and effectiveness in the production of goods and services, a multitude of complex and interconnected factors come into play. With that in mind, could you provide an extensive exploration of the various facets of operations management, encompassing topics such as the strategic significance of operations within businesses, the core principles of managing processes, resources, and quality, and how operations management contributes to achieving a competitive advantage and meeting customer demands in an ever-changing global marketplace? Furthermore, how do contemporary operations management practices adapt to the evolving landscape of business, including the impact of technological innovations, supply chain disruptions, and sustainability concerns, and what challenges and opportunities do these changes present for operations managers in terms of optimizing processes, reducing costs, and mitigating environmental impact? Additionally, what are the essential methodologies and tools employed in operations management, such as lean production, Six Sigma, Total Quality Management, and Just-in-Time inventory, and how do these frameworks improve operational efficiency and customer satisfaction?

Moreover, considering the crucial role of supply chain management in operations, how do organizations manage the flow of materials, information, and finances across a global network of suppliers and distributors, and what strategies and technologies are being harnessed to enhance supply chain visibility, responsiveness, and resilience in the face of unexpected disruptions like the COVID-19 pandemic? Additionally, how do ethical considerations and sustainable practices align with modern operations management principles, and what measures are being taken to ensure responsible sourcing, waste reduction, and eco-friendly production methods in an effort to meet environmental and social responsibility goals?