SIGNAL is an innovative earth exploration mission proposal with the main objective to estimate accurately and repeatedly topography and topographic changes associated with mass change or other dynamic effects on glaciers, ice caps and polar ice sheets. Elevation measurements are complemented with glacier velocity measurements, providing valuable additional information for a better understanding of the hydrology of glacierized basins and of the Arctic and Antarctic water cycle. SIGNAL is capable of monitoring all critical regions with a high spatial resolution and an adequate revisit time. This paper gives an overview about the actual mission design status and provides a brief description of the topography (DEM - digital elevation map) self-calibration strategy and the estimated global interferometric performance.

Causal connections between mesoscale wind patterns and moisture distribution in the lower boundary layer can be studied using satellite synthetic aperture radar (SAR) observations. Wind information is retrieved from radar backscatter intensity over water areas, whereas the moisture distribution is reflected in the radar signal delay. The latter can only be observed over land areas, using the interferometric combination of two radar images. This paper reports on the relation between wind and moisture associated with boundary layer rolls and with a cold-frontal rain band. The combination of both signals, originating from one sensor, is used to infer a quantitative description of the underlying dynamical processes.