# Satellite and Ground Based Thermal Observation of the 2014 Effusive Eruption at Stromboli Volcano
## 4 Results
### TET-1 Observations  
Figure 5 shows 18 processed datasets (MIR band temperature corrected for emissivity and atmospheric effects). Another 9 datasets were acquired but these situations were mostly too cloudy to be used. The presented data were atmospherically corrected and shows temperatures.  
The lowest temperature was detected on clouds during the night (see Figure 5 for the date 2 September 2014). Clouds seem to be warmer during the daytime, which is a consequence of the reflected solar irradiance. The Tyrrhenian Sea around the island had a relatively constant temperature of approximately 27 \({}^{\circ}\)C in August and September, indicating merely small diurnal variations, thus it appears as a constant background. The island itself shows significantly higher diurnal deviations (\(\sim\)15 \({}^{\circ}\)C) with maximum temperatures of over 30 \({}^{\circ}\)C. Most prominent in Figure 5 are the lava flows, which stand out with their red-orange-yellow colors on most scenes. It is obvious that the number of  
Figure 5: TET-1 MIR temperature corrected for emissivity and atmospheric effects over Stromboli. Lava flows appear in red-orange-yellow colors while the background appears in black-blue-green colors.  
pixels associated with the high temperature anomaly varies significantly, e.g., the number of pixels covering the active lava flow reduces to a single pixel on 5 September 2014.  
Two main reasons influenced this high variability. Firstly, the cloud coverage varied significantly from scene to scene, for instance a hotspot was detected on 2 September 2014, but its quantification is likely to contain a huge error due to cloud coverage. Therefore, images from 2, 5, 12, 20, 26 and 30 September were not further considered. In addition, the morning overpass on 16 September also had problems in the TIR channel, thus, it was not processed either. The second reason is the highly variable lava production rate of the volcano. Most scenes clearly reveal two separate lava flows. Sometimes they converge into one on their way to the sea. The spatial resolution of TET-1 data are still too coarse to identify the exact position of the vent or exact length of each flow. The longest flow identified (25 August 2014) is estimated to 6 TET-1 pixels, which is, considering that the first and the last pixel are not fully covered by the flow, \(\sim\)800 m (map and not slope distance). Considering the average slope of the Sciara del Fuoco is 37\({}^{\circ}\), the elevation difference between the effusive vent and the lava front was 600 m. As the vent was located 650 m a.s.l., the lava front almost reached the sea.  
Figure 6 shows the estimated _TADR_ based on TET-1 data. Instead of producing a single value per scene, we show the minimum and maximum estimates. The reason behind this lies in the poor knowledge of precise values for some parameters in Equation (7). As previously proposed [5, 6, 23, 55], we thus provide two datasets ranging from the lowest (min _TADR_) to the highest possible estimate (max _TADR_). The used parameters are listed in Table 6.  
In order to ignore the effect of heat conduction into the adjacent rock we used the minimum value of 0 W/m\({}^{2}\)/K in the min model for lava thermal conductivity \(k\). The convective heat transfer coefficient \(h_{c}\) has the greatest impact on the results. [PERSON] _et al._[23] suggested a value of \(\sim\)10 W/m\({}^{2}\)/K for Stromboli, thus we used 10 W/m\({}^{2}\)/K for the min model and 15 W/m\({}^{2}\)/K for the max model.