I am looking for the population and the surface area (in square kilometers) for several cities throughout the globe. I found several datasets available in GRUMP, but I didn't find anything with both population and surface area.
The GRUMP urban extents dataset will show population and land area for “cities”. However, please note that GRUMP Beta urban extents information is primarily derived from night-time lights that measure the extent of lit areas, among other things. This means that in well-lit areas or where cities are close together, multiple cities may in fact be part of the same light, and so are considered part of the same contiguous urban extent. The data for many urban extents, therefore, includes the sum of the population for the cities that fall within a single light. Thus, it is possible that our urban extents data for a city you would like to measure include not only the city in question, but also neighboring cities / suburbs.