Martian Surface / Atmosphere Web Interface

Aeolian processes are a dominant agent of surface modification on Mars, and the distribution, orientation, and morphology of wind-formed bedforms provide key constraints on both present-day atmospheric circulation and past climatic conditions. However, direct measurements of near-surface winds are limited to a small number of landing sites, restricting our ability to characterize wind regimes at regional and global scales. Atmospheric General Circulation Models (GCMs) therefore play a central role in reconstructing Martian wind patterns, but their outputs require substantial post-processing to be meaningfully compared with geomorphological observations. Systematic and accessible tools that link atmospheric simulations to aeolian surface processes are essential for model validation and for interpreting the climatic significance of observed landforms.
We present the Martian Surface/Atmosphere Web Interface, a freely accessible, web-based platform designed to facilitate the investigation of wind-driven sediment transport and bedform formation on Mars. The interface is built upon atmospheric simulations produced by the NASA Ames Global Circulation Model and provides an integrated workflow that converts modeled near-surface winds into quantitative predictions of sand flux and bedform orientations. By enabling remote execution of computationally intensive analyses through a user-friendly interface, the platform removes the need for local installations and specialized expertise in handling large GCM datasets.
Sand fluxes are derived using two complementary parameterizations that reflect different physical assumptions about aeolian transport. The first follows the formulation of Kok (2010), which accounts for saltation hysteresis by distinguishing between fluid and impact thresholds, allowing sediment transport to persist under lower wind stresses. The second approach is based on Rubanenko et al. (2023) and adopts the Martin and Kok (2017) saltation flux law, which assumes a linear scaling of sediment flux with shear stress, supported by field observations and theoretical considerations of splash-dominated entrainment. The parallel implementation of these formulations allows users to evaluate the sensitivity and robustness of transport predictions.
The resulting sand fluxes are further used to estimate bedform orientations through implementations of two end-member formation mechanisms: the bed instability mode and the elongation mode. The interface provides directional statistics and circular plots of transport vectors, enabling rapid comparison between modeled wind regimes and observed aeolian patterns. The underlying simulation dataset spans approximately the last 400 kyr of Martian climate history and explores a broad range of climatic scenarios, including variations in atmospheric pressure, axial obliquity, orbital eccentricity, and longitude of perihelion. These parameters capture the influence of orbital forcing and atmospheric density on near-surface winds and sediment transport.
The Martian Surface/Atmosphere Web Interface provides a unified and accessible framework to explore surface–atmosphere interactions across Mars. It supports the validation of atmospheric models, aids in distinguishing active from relict aeolian landforms, and offers new opportunities to investigate the role of climatic variability in shaping the Martian surface through time.