 Combining satellite-based passive and active microwave sensors has the potential to improve global scale estimates of surface soil moisture by adjusting them to the same range and preserving their dynamics. The methodology developed rescales volumetric soil water content from AMSRE and degree of saturation from ASCET against a reference land surface model data set using a cumulative distribution function matching approach. Merging these different satellite products increases the number of observations while minimally changing the accuracy of soil moisture retrievals in transitional regions, delineating the boundary between sparsely and moderately vegetated regions. The combination method developed can be applied to existing microwave satellites as well as new missions, enabling the development of a long-term global soil moisture data set that enhances basic understanding of the role of soil moisture in the water, energy, and carbon cycles. This article was authored by Y.Y. Lu, R. M. Paranissa, W.A. Derigo, and others. We are article.tv, links in the description below.