Quasi-periodic climate changes on Mars - A review

Abstract

The current understanding of the manner in which astronomical variations modulate the Martian climate and thereby lead to the occurrence of laminated polar terrain is considered. The seasonal cycles of dust, carbon dioxide and water, and their responses to astronomical variations, are studied. After an assessment of the way in which these cycles presently operate, for which pertinent spacecraft and ground-based observations are extant, attempts to predict how these cycles may differ under conditions of high and low obliquity and eccentricity are discussed. Attention is given not only to those areas in which there is broad agreement, but also to the controversial and speculative. Key questions include the proportion of dust and water ice in the laminae and its variations within individual layers, the relative importance of older laminae and lower-latitude material as sources of new laminae, and the factors responsible for the youth of the laminated terrain.