We investigate the effects of varying temperature and chemical potential on the optical absorption spectrum of (001) surface states of topological crystalline insulator SnTe using a four-band effective $k{\cdot}p$ Hamiltonian. Absorptions have maximal intensity at 0~K or when chemical potential is located at the charge neutrality point. If a given sample's chemical potential is well-controlled, conventional infrared spectroscopy may be used to identify the spectral signatures of SnTe (001) surface states at room temperatures and without use of large magnetic fields. We also investigate the generation of high harmonic radiation resulting from an ultrafast intense linear optical pulse on the (001) surface of thin film topological crystalline insulator SnTe. Model parameters such as amplitude of the electric field, band gap, chemical potential and pulse polarization would were found to strongly affect the cutoff frequency and yield of the far field radiation. The cutoff frequency of the high harmonic far field spectrum was found to be solely determined by the anomalous current. The yield of far field radiation was found to be either predominantly by semiclassical current or by the anomalous current or equally by the combination of these two currents. Large amplitudes of the electric field of the pulse, small band gaps and initial charge carrier population limited to regions near the gapped Dirac point tended to favor anomalous current. Conversely, small amplitudes of the electric field of the pulse, large band gaps and initial charge carrier population that extended further away from regions near the gapped Dirac point tended to favor semiclassical current.