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[1] Two parallel experiments involving the evolution and runup of plunging solitary waves on a sloping bed were conducted: (1) a rigid-bed experiment, allowing direct (hot film) measurements of bed shear stresses and (2) a sediment-bed experiment, allowing for the measurement of pore water pressures and for observation of the morphological changes. The two experimental conditions were kept as similar as possible. The experiments showed that the complete sequence of the plunging solitary wave involves the following processes: shoaling and wave breaking; runup; rundown and hydraulic jump; and trailing wave. The bed shear stress measurements showed that the mean bed shear stress increases tremendously (with respect to that in the approaching wave boundary layer), by as much as a factor of 8, in the runup and rundown stages, and that the RMS value of the fluctuating component of the bed shear stress is also affected, by as much as a factor of 2, in the runup and hydraulic jump stages. The pore water pressure measurements showed that the sediment at (or near) the surface of the bed experiences upward directed pressure gradient forces during the down-rush phase. The magnitude of this force can reach values as much as approximately 30% of the submerged weight of the sediment. The experiments further showed that the sediment transport occurs in the sheet flow regime for a substantial portion of the beach covering the area where the entire sequence of the wave breaking takes place. The bed morphology is explained qualitatively in terms of the measured bed shear stress and the pressure gradient forces.

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Sea surface temperature (SST) is a fundamental physical variable for understanding, quantifying and predicting complex interactions between the ocean and the atmosphere. Such processes determine how heat from the sun is redistributed across the global oceans, directly impacting large-and small-scale weather and climate patterns. The provision of daily maps of global SST for operational systems, climate modeling and the broader scientific community is now a mature and sustained service coordinated by the Group for High Resolution Sea Surface Temperature (GHRSST) and the CEOS SST Virtual Constellation (CEOS SST-VC). Data streams are shared, indexed, processed, quality controlled, analyzed, and documented within a Regional/Global Task Sharing (R/GTS) framework, which is implemented internationally in a distributed manner. Products rely on a combination of low-Earth orbit infrared and microwave satellite imagery, geostationary orbit infrared satellite imagery, and in situ data from moored and drifting buoys, Argo floats, and a suite of independent, fully characterized and traceable in situ measurements for product validation (Fiducial Reference Measurements, FRM). Research and development continues to tackle problems such as instrument calibration, algorithm development, diurnal variability, derivation of high-quality skin and depth temperatures, and areas of specific interest such as the high latitudes and coastal areas. In this white paper, we review progress versus the challenges we set out 10 years ago in a previous paper, highlight remaining and new research and development challenges for the next 10 years

The QuikSCAT mission provided valuable daily information on global ocean wind speed and direction from July 1999 until November 2009 for various applications including numerical weather prediction, ocean and atmospheric modelling. One new and important application for wind vector satellite data is offshore wind energy, where accurate and frequent measurements are required for siting and operating modern wind farms. The greatest advantage of satellite observations rests in their extended spatial coverage. This paper presents analyses of the 10 year data set from QuikSCAT, for the overview of the wind characteristics observed in the North and Baltic Seas, where most of Europe's offshore wind farms operate and more will be constructed. Significant issues in data availability are identified, directly related to the flagging schemes. In situ observations from three locations in the North Sea are used for comparisons. Mean biases (in situ minus satellite) are close to zero for wind speed and −2.7 ı for wind direction with a standard deviation of 1.2 m s 1 and 15 ı , respectively. The impact of using QuikSCAT and in situ measurements extrapolated to 10 m for wind power density estimations is assessed, accounting for possible influences of rain-contaminated retrievals, the sample size, the atmospheric stability effects and either fitting the Weibull distribution or obtaining the estimates from the time series of wind speed observations.