At 1km resolution, this is largely just a map of US urbanized areas. The spatial variation isn't that interesting. The temporal variation and the absolute values per spatial unit are the greater value of this project.
That is unfair. The largest co2 producers are also large in size. I think 1km resolution is more than sufficient to identify the source of the majority of emissions - e.g. factories, power plants, buildings, etc. Even if the resolution is not fine-grained enough for definitive identification it reduces the scope to manageable size for more detailed investigations.