In the next decade we will mine the meteorological predictability associated with measured storage of atmospherically-accessible water on land-surfaces

In the late 1980s and 1990s meteorologists learned to extract the predictability associated with fluctuations in sea surface exchanges and to document these fluctuations by combining remotely sensed data with ocean surface sampling. There is ample evidence that the atmosphere is sensitive to land-surface exchanges but hitherto mining the associated predictability has been hampered by the absence of measurements of the atmospherically-accessible water stored on land-surfaces. This will change in the coming decade because of the availability of relevant remote sensing data and, crucially, cosmic-ray based surface measurements of field-scale average land surface water storage. This lecture will review progress made under the COsmic-ray Soil Moisture Observing System (COSMOS) towards implementing and applying the required network of stationary and mobile cosmic-ray sensors needed to extract predictability. Topics covered will include (a) improved understanding of the sensitivity of measured near-surface cosmic-ray intensity to surface water present as transient soil moisture (pore water), chemically combined with soil (lattice water), as frozen precipitation, and in vegetation and near-surface water vapor; (b) theoretical and methodological development of techniques to allow assimilation of cosmic-ray surface water data into land surface parameterizations in meteorological models; and (c) ongoing development of the COSMIC Rover, a mobile cosmic-ray sensor system appropriate for the pixel scale calibration and validation of remote sensing data.