From Universe Today: “Although the bright haze of Venus’s atmosphere has been identified, many dark patches have also been observed. So far, there is no explanation for these patches of atmospheric chemicals absorbing solar UV“.
In the meanwhile, raypierre of RealClimate summarizes the latest info about the atmosphere of Venus, but somehow forgets to include the UV absorption mystery (it only shows up as an afterthought, comment #2).
One wonders why? Obsession with consensus and the need to demonstrate there exist such a thing as “climate science” spring to mind.