Hartsfield-Jackson International Airport said it  has had a more than 40 percent increase in weekly cargo flights compared with last year. However, cargo tonnage at the airport increased only about 2 percent in the first six months of the year compared with the same period of last year.

According to the airport, cargo carriers have added about 24 monthly flights this year, including additional flights from Asiana Airlines, China Cargo Airlines and Singapore Airlines.

Some of the flight additions have yet to take effect. That's one reason cargo tonnage in the first six months of the year didn't increase nearly as much as the number of cargo flights this year. Another reason is that some of the flights make multiple stops, so they aren't full upon arrival or departure in Atlanta, according to Hartsfield-Jackson.