The MacBok Air generally have temperature issues but I have never seen such high temperatures. I searched the web and hoped to find a solution and yet again the web was to great help. The problem was old thermal grease.

It is quite easy to disassemble a MacBook Air and replace the old CPU thermal paste (http://www.ifixit.com/Teardown/MacBook-Air-Teardown/598/). Remove the old paste with a bit of help acetone, apply the new paste, …

After 15 minutes of work my Air is not running at 102 celsius but ‘only’ 51 celsius.

If you are unhappy with the noise that the MacBook Air makes to keep itself cool try playing with the fan speed (can be dangerous). Read more about it at http://horstr.blogspot.com/2008/04/dont-throw-your-macbook-air-out-just.html