Maybe I am misinformed but I was under the impression part of the reason concorde was retired is because at those speeds you tear up the ozone.

"From their particle measurements, the authors of the Science study calculate that a future possible fleet of 500 supersonic passenger aircraft will increase the surface area of particles in the atmosphere by an amount similar to that following small volcanic eruptions. In mid-latitude regions, such emissions have the possibility of increasing ozone loss above that expected for nitrogen oxide emissions alone. The increase in the number of particles may also affect the ozone-related processes occurring on wintertime polar stratospheric clouds (PSCs) in the polar regions."

-http://www.publicaffairs.noaa.gov/pr95/oct95/noaa95-65.html