963 resultados para summer residence


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During summer seasons (from 2012 to 2015) high resolution observation were performed in the Civitavecchia coastal area (Northern Tyrrhenian sea, west coast). All sampling was carried out from a small boat (5m rigid inflatable) starting in the early morning typically around 06:00 a.m. , and lasting from 2 to 8 h, depending on the weather conditions. The purposes of the experiment was to observe the variations of both the coastal circulation and the water column in response to rotation of 180 ° in the wind direction. During surveys both current measurements and yo-yo time series were performed. Current data were acquired using an ADCP SonTeck (500 Khz, sampling interval from 20sec to 60 sec, average interval 50% sampling, cell thickness 1 meter) and the yo-yo time series employing a small instrument package (CTD). The CTD contained an Idronaut 316 Plus and a SeaPoint fluorometer. The sampling rate for the CTD was 10Hz, profiling with the CTD was done by allowing the instrument package to free-fall, at an average descent rate of 1 m/s. During the summer 2012, the sampling plan consisted in four stations spaced a quarter of a mile (St. 1 - 10 m; St. 2 - 20 m; St. 3 - 30 m; and St. 4 - 40 m), in which yo-yo time series were performed with an interval of 20 min. In order to study fluorescence of Chlorophyll a pathes distribution in coastal zone. Breeze induced circulation was the goal of the following summers surveys, in these current measurements and yo-yo time series were performed moored at a depth of 40 m. Offshore station (St. 1 -40m) has been chosen to perform measurement, basis of previously observations (2012 sampling surveys). It was decided as wind driven circulation and mixing phenomena are less influenced by seabed than the other stations. Acquired data have been processed by NEMO SeaDataNet software.

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Remote sensing instruments are key players to map land surface temperature (LST) at large temporal and spatial scales. In this paper, we present how we combine passive microwave and thermal infrared data to estimate LST during summer snow-free periods over northern high latitudes. The methodology is based on the SSM/I-SSMIS 37 GHz measurements at both vertical and horizontal polarizations on a 25 km × 25 km grid size. LST is retrieved from brightness temperatures introducing an empirical linear relationship between emissivities at both polarizations as described in Royer and Poirier (2010). This relationship is calibrated at pixel scale, using cloud-free independent LST data from MODIS instruments. The SSM/I-SSMIS and MODIS data are synchronized by fitting a diurnal cycle model built on skin temperature reanalysis provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). The resulting temperature dataset is provided at 25 km scale and at an hourly time step during the ten-year analysis period (2000-2011). This new product was locally evaluated at five experimental sites of the EU-PAGE21 project against air temperature measurements and meteorological model reanalysis, and compared to the MODIS LST product at both local and circumpolar scale. The results giving a mean RMSE of the order of 2.2 K demonstrate the usefulness of the microwave product, which is unaffected by clouds as opposed to thermal infrared products and offers a better resolution compared to model reanalysis.