Long‐duration time series of the chemical composition of fumaroles and of soil CO2 flux reveal that important variations in the activity of the Solfatara fumarolic field, the most important hydrothermal site of Campi Flegrei, occurred in the 2000–2008 period. A continuous increase of the CO2 concentrations and a general decrease of the CH4 concentrations are interpreted to be the consequence of the increment of the relative amount of magmatic fluids, rich in CO2 and poor in CH4, hosted by the hydrothermal system. Contemporaneously, the H2O‐CO2‐He‐N2 gas system shows remarkable compositional variations in the samples collected after July 2000 with respect to the previous ones, indicating the progressive arrival at the surface of a magmatic component different from that involved in the 1983–1984 episode of volcanic unrest (1983–1984 bradyseism). The change starts in 2000, concurrently with the occurrence of relatively deep, long‐period seismic events which were the indicator of the opening of an easy ascent pathway for the transfer of magmatic fluids toward the shallower, brittle domain hosting the hydrothermal system. Since 2000, this magmatic gas source is active and causes ground deformations and seismicity as well as the expansion of the area affected by soil degassing of deeply derived CO2. Even though the activity will most probably be limited to the expulsion of large amounts of gases and thermal energy, as observed in other volcanoes and in the past activity of Campi Flegrei, the behavior of the system in the future is, at the moment, unpredictable.

To determine the CO 2 consumption due to chemical weathering in the Alps, water samples from the 32 main Alpine rivers were collected and analysed in two periods, spring 2011 and winter 2011/2012. Most of the river waters are characterized by a bicarbonate earth-alkaline composition with some samples showing a clear enrichment in sulphates and other samples showing a slight enrichment in alkaline metals. The amount of total dissolved solids (TDS) ranges between 96 and 551 mg/L. Considering the major ion composition and the Sr isotopic composition of water samples, coherently with the geological setting of the study area, three major reservoirs of dissolved load have been recognized: carbonates, evaporites and silicates. Based on a chemical mass balance, the flux of dissolved solids, and the flux of carbon dioxide consumed by chemical weathering have been computed for each basin and for the entire study area. Results show that the flux of dissolved solids, ranges from 8 × 10 3 to 411 × 10 3 kg km −2 y −1 , with an average value of 127 × 10 3 kg km −2 y −1 , while the flux of carbon dioxide consumed by chemical weathering in the short-term (b 1 Ma) is 5.03 × 10 5 mol km −2 y −1 1 on average. Since part of the CO 2 is returned to the atmosphere through carbonate precipitation and reverse weathering once river water reaches the ocean, the CO 2 removed from the atmosphere/soil system in the long-term (N 1 Ma) is much smaller than the CO 2 consumed in the short-term and according to our calculations amounts to 2.01 × 10 4 mol km −2 y −1 on average. This value is almost certainly a minimum estimate of the total amount of CO 2 fixed by weathering on the long-term because in our calculations we assumed that all the alkaline metals deriving from rock weathering in the continents are rapidly involved in the process of reverse weathering in the oceans, while there are still large uncertainties on the magnitude and significance of this process. The values of CO 2 flux consumed by weathering are strongly correlated with runoff while other potential controlling factors show only weak correlations or no correlation. Our estimation of the CO 2 consumed by weathering in the Alpine basins is in the same order of magnitude, but higher than the world average and is consistent with previous estimations made in river basins with similar climatic conditions and similar latitudes.

Despite abundant information on landslides, and on landslide hazard and risk, in Italy, little is known on the direct impact of event landslides on road networks and on the related economic costs. We investigated the physical and economic damage caused by two rainfall-induced landslide events in Central and Southern Italy, to obtain road restoration cost statistics. Using a GIS-based method, we exploited road maps and landslide event inventory maps to compute different metrics that quantify the impact of the landslide events on the natural landscape and on the road networks, by road type. The maps were used with cost data obtained from multiple sources, including local authorities, and specific legislation, to evaluate statistically the unit cost per metre of damaged road and the unit cost per square metre of damaging landslide, separately for main and secondary roads. The obtained unit costs showed large variations which we attribute to the different road types in the two study areas and to the different abundance of landslides. Our work confirms the long-standing conundrum of obtaining accurate landslide damage data and outlines the need for reliable, standardized methods to evaluate landslide damage and associated restoration costs that regional and local administrations can use rapidly in the aftermath of a landslide event. We conclude recommending that common standardized procedures to collect landslide cost data following each landslide event are established, in Italy and elsewhere. This will allow for more accurate and reliable evaluations of the economic costs of landslide events.

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