Enlarge / Aerial view of the exclusive island of luxury hotels and residences of The Palm Jumeirah in Dubai, United Arab Emirates. (credit: Vicki Jauron, Babylon and Beyond Photography)

Each year, humans add a little more land to their coastlines, slowly but surely encroaching on the sea and filling up smaller coastal bodies of water with new developments. This encroachment typically comes as we add luxury waterfronts and extend ports farther out to sea. In all, since 2000, coastlines around the world—specifically in urban areas—grew a whopping 2,530 square kilometers, according to a new paper.

A press release about the research notes that this is around 40 Manhattans, while the paper itself points out that this is roughly the size of Luxemburg. Neither source said this, but it’s also more than 4,000 Dollywoods.

The paper—which claims to be the “first global assessment of coastal land reclamation"—looked at how human development built land in, or filled parts of, coastal zones. This includes wetlands, which play various important roles like slowing erosion (but humans can just keep building out anyway, right?), protecting areas further inland from flooding and sea level rise, and acting as habitats for myriad species.