Table 1. Main characteristics of the samples.
| Biological data | Meteorological data | Chemical data | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample ID | Local sampling starting date and time | Local sampling ending date and time | Cloud type* | Sample volume filtered and used for sequencing (mL) [equivalent air volume (m3)] | Total prokaryotic cells concentration (mL-1) | Total eukaryotic cells concentration (mL-1) | T (°C) | Wind speed (m s-1) | Wind direction (°/N) | LWCb (g m-3) | Dissolved ions concentrations (μM) | ||||||||||||
| Mean | SEa | Mean | SEa | Mean | SEc | Mean | SEc | Mean | SEc | Mean | SEc | pH | Na+ | SEa | Cl- | SEa | NO3- | SEa | |||||
| CLOUD 1 | 10/11/13 10:36 AM | 10/11/13 1:25 PM | Polluted | 94 [304 m3 of cloudy air] | 8.23×103 | ± 1.25×103 | 8.67×102 | ± 3.15×102 | -1.2 | ± 0.2 | ND* | - | ND* | - | 0.16 | ± 0.06 | 4.2 | ND | - | ND | - | ND | - |
| CLOUD 2 | 10/14/13 10:00 PM | 10/15/13 11:10 AM | Continental | 350 [1422 m3 of cloudy air] | 9.49×103 | ± 2.87×103 | 2.83×102 | ± 1.05×102 | 6.5 | ± 0.3 | 12.1 | ± 1.5 | 218 | ± 9 | 0.31 | ± 0.05 | 4.7 | 79.0 | ± 6.5 | 15.5 | ± 2.8 | 38.5 | ± 0.8 |
| CLOUD 3 | 11/5/13 2:45 PM | 11/6/13 1:30 PM | Marine | 420 [2457 m3 of cloudy air] | 2.05×103 | ± 1.39×103 | 4.42×101 | ± 0.21×102 | 6.8 | ± 0.8 | 18.3 | ± 3.4 | 337 | ± 4 | 0.40 | ± 0.07 | 5.6 | 188.5 | ± 12.6 | 0.2 | ± 0.1 | 1.13 | ± 0.7 |
ND: Not determined.
*According to the classification of clouds sampled at the puy de Dôme as established by [58] (see S2 Fig), based on pH, ion content and backtrajectory plots (shown in S1 Fig).
aStandard error of 3 replicate measurements.
bLiquid water content.
cStandard error of averages of meteorological variables collected every 5 minutes during sampling.