Water Vapor Density Variations (IMAGE) Moscow Institute of Physics and Technology Caption Water vapor density variations depending on season (horizontal axis) and latitude (vertical axis) throughout the year: (a) represents experimental data, (b) is a numerical simulation, and (c) is the difference between the two. Credit Credit: Dmitry Shaposhnikov et al./<em>Journal of Geophysical Research: Planets</em> Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.