| Summary: | New laboratory measurements and theoretical calculations of integrated line intensities for water vapour bands in the near-infrared and visible regions (860015000 cm(-1)) show a systematic 6 to 26% increase in band intensities compared to the HITRAN96 database. The recent corrections to HITRAN96 (Giver et al, 2000) do not remove these discrepancies - in fact increasing them to 6 to 38%. A line-by-line code is used to assess the effects of such changes in the water vapour spectral database on calculations of short-wave fluxes and heating rates for three standard atmospheres. It is found that, compared with HT96 results, the absorbed downward solar fluxes increase by 4.8, 5.5 and 2.2 Wm(-1) (solar zenith angle = 30degrees) and by 2.1, 2.4 and 1.1 Wm(-2) (solar zenith angle = 75degrees) for mid-latitude summer, tropical and sub-arctic winter atmospheres respectively. The maximum percentage change in heating rate is about 4%.
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