Not a lot. Directly on the emissions at their origin, like capturing inside a cement plant, sure. In a city or region near the cement plant not so much. The di

Not a lot. Directly on the emissions at their origin, like capturing inside a cement plant, sure. In a city or region near the cement plant not so much. The difference is probably 1-15 ppm depending on the city. (Making up numbers for the example,) imagine 420 ppm in remote Iceland and 425-430 ppm in NYC. Now consider the cost of land in the two locations and the couple percent difference in CO2 concentration clearly isn't at all worth it. Iceland also has volcanoes and lots of accessible underground basalt which makes this form of storage work best.