"The Russian adventurer Fedor Konyukhov has broken the record for the fastest circumnavigation of the earth in a hot air balloon in 2016. The 64-year-old has beaten the late Steve Fossett’s record of circumnavigating the world by two days, making the 34,000km journey in just 11 days flying at heights of up to 10km." - The Guardian.
Which extra distance would the adventurer travel if it is 12 km above the ground?