Is accumulation and runoff the same thing?

No, accumulation and runoff are not the same thing. Accumulation refers to the process where water, snow, or ice gathers in a specific area, typically in the form of precipitation or melting ice. Runoff, on the other hand, is the movement of water, often from rain or melted snow, over the land surface and into rivers, lakes, or oceans. While both processes are related to the water cycle, they represent different phases of water movement and storage.