High resolution Fourier transform spectra of the atmosphere in the 2850--2950 cm-1 region have been recorded from the ground using the sun as a source. For the first time, many NO2 absorption peaks belonging to the &ngr;1+&ngr;3 band and its associated hot band &ngr;1+&ngr;2+&ngr;3-&ngr;2 have been located. Among them, 13 well isolated features have been used to determine NO2 vertical column densities. Indeed, from the analysis of 4 spectra recorded at air masses of 10.7, 5.4, 3.1, and 10.8, that is for the 3 first ones just after sunrise and in the early morning and for the last one just before sunset, vertical column densities of 1.84¿0.34, 1.80¿0.28, 1.74¿0.44, and 3.24¿0.46 1015 molecule⋅cm-2 have been obtained. The good absolute accuracy of these results is due to the use of several lines having a wide enough range of intensities and of lower state energy levels.