Organic Carbon Cycle in the Atmosphere of Venus

Abstract

The community commonly assumes that the Venusian atmosphere lacks organic (reduced) carbon. This is reflected in the literature, which now for almost a half a century does not mention organic carbon in connection with the Venus atmosphere. This assumption persists despite the failure of models that exclude organic carbon to account for many well-established observed features of the Venusian atmosphere. Here is presented a model summarizing reactions that almost certainly are occurring in the Venusian atmosphere. The model relies on reactions of reduced carbon compounds known to occur in concentrated sulfuric acid (CSA), under high pressure and high temperature, many used in industrial processes. Inclusion of this known chemistry into a model for the Venus atmosphere accounts for several as yet unexplained observations. These include the upper haze, the lower haze, and the "mysterious" UV-blue absorber. This article also suggests, as a historical perspective, that a long-forgotten dispute is responsible for the persistent assumption of absence of interesting organic chemistry in the clouds of Venus.