Why specify height? 22:21 May 27, 2011
For precision's sake.
Whether the temperature is measured at 1395 metres or 1405 metres above sea level probably makes little difference, assuming it is measured at the same height above ground level at those altitudes, but as with low-flying aircraft I suspect there is a "ground effect" when it comes to temperature, so the temperature close to the ground might be considerably higher, or lower, than the temperature a given height above the ground.
When you refer to normal body temperatures, you specify the place where the temperature is taken: 37° (anal), 36.6° (oral), etc. (assuming you use the same thermometer) [yuck!]. | 
approbation des pairs (net) : +5