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[1] We use a parameterized convection model to investigate the effects of deep water cycling on the thermal evolution of an Earth-like planet. The model incorporates two water reservoirs, a surface and an interior mantle reservoir. Exchange between the two is calculated using a mantle convection parameterization that allows for temperature-and water-dependent mantle viscosity together with internally self-consistent degassing and regassing parameterizations. The balance between degassing and regassing depends on the average spreading rate of tectonic plates, the amount of water partitioned into melt, the thickness of a mantle melt zone, and of a hydrated layer at the top of subducting plates. Degassing scales with melt zone thickness such that an early period of extensive melting would create a drier and more viscous mantle, shifting the solidus line in a direction that would reduce the melt zone thickness and the rate of mantle heat loss. Coupling a hydrated zone thickness-dependent regassing factor to the model, to mimic water delivery to the mantle via a serpentinized layer, allows for the potential of a reversing point where the overall water flow direction switches from degassing to regassing as the mantle cools. The water effect on viscosity creates a negative feedback that tends to regulate the final amount of water in the mantle so it is not strongly dependent on the initial amount of planetary water. The final amount of water in the surface reservoir is then determined by this feedback effect together with the initial water budget of the entire planet. This implies that if the initial water budget of a planet can be estimated, from planetary formation models, then the volume of surface water can be used to estimate the volume of water in the mantle of an Earth-like planet. Applying this methodology to the Earth leads to predictions for water concentration in the Earth's mantle that are in line with geochemical and petrological constraints.

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The volcanic and magnetic activity on the surface of Mars is directly related to its thermal evolution and to the melting potential of its mantle. Mars does not have an internal magnetic field today but geologic evidence suggests a dynamo was active during the first 500 to 800 million years of Martian history. The existence of the magnetic field on the planet sets a lower bound on the vigor of convection within its liquid core. The vigor of core convection can be maintained by efficient cooling of the overlying mantle. An initially wet mantle will promote strong convection, rapid core cooling, and dynamo activity. Magmatic degassing and planetary cooling increases the mantle's viscosity, thus decreasing the rate of core cooling and possibly terminating dynamo activity. The timescale for ending core dynamo activity is controlled by the initial amount of water in the mantle and by the efficiency of the degassing process. This process is an alternative to recent models that postulate dynamo termination on Mars is controlled by impact heating of the mantle.

Damage assessment from very high resolution (VHR) remote sensing imagery plays a fundamental role in the delineation of the impact caused by catastrophic events. To date internationally accepted standard guidelines on how to assess damages to building using vertical imagery have not yet been developed. This study therefore proposes a building damage scale and related interpretation guidelines to be operationally adopted as a standard by the main stakeholderstailored to analyses based on VHR remote sensed vertical imagery. Preliminarily, some of the damage scales used for building damage assessment by the main satellite-based emergency mapping services have been analysed and discussed. A quantitative thematic accuracy analysis based on the open accessible crisis datasets related to the earthquake occurred in Central Italy in August 2016 has been carried out. The results highlight that by using VHR remotely sensed images it is not possible to directly apply damage classification scales addressing slight structural damages (e.g. the lowest grades proposed by EMS-'98). The paper demonstrates that using different damage classes and detailing the interpretation guidelines with operational examples is essential to increase the thematic accuracy of the analysis.