Environmental Data: CCN, hygroscopicity, predicted cloud droplet numbe...

CCN data Weissfluhjoch

In-situ CCN measurements were conducted between February 24 and March 8 2019 at Weissfluhjoch. The data file contains: * Date and time (DD/MM/YYYY hh:mm:ss) in UTC * Filtered CCN number concentrations (in cmˉ³) measured at 6 discrete supersaturations (SS) ranging from 0.09% to 0.74%. The name of each CCN column is indicative of the SS developed within the instrument. * Instrument characteristics such as sample temperature (in °C) and pressure (in mbar) * A code that refers to the reason of filtering. Missing or filtered CCN values are indicated by "-999", while a declaration of each "Error_code" can be found in the following list: _Error_code_: __0000__: Measurements without error __1000__: Period of transient operation after a supersaturation change __2000__: Sharp change (decrease) in the room temperature housing the instrument, which induces a reset in column temperature __3000__: Irregular values in the room temperature housing the instrument __9999__: Missing data

Hygroscopicity parameter Weissfluhjoch

The aerosol hygroscopicity parameter is derived combining the CCN and SMPS size distribution data collected between February 24 and March 8 2019 at Weissfluhjoch. The data file contains: * Date and time (DD/MM/YYYY hh:mm:ss) in UTC * The instrument supersaturation (SS%) * The calculated hygroscopicity parameter (kappa) * The calculated critical dry diameter of the particles (Dcr) in nm. Missing values are indicated by "-999".

Predicted cloud droplet number concentrations Weissfluhjoch

In-situ measurements of aerosol size distributions along with updraft velocities collected from a wind Doppler Lidar are coupled with a state-of-the art droplet activation parameterization (Morales and Nenes, 2014) to determine the cloud droplet number and maximum in-cloud supersaturation that can potentially form over the Weissfluhjoch station between February 24 and March 8 2019. For this, a hygroscopicity parameter of 0.25 is assumed, according to the CCN-derived values. The data file contains: * Date and time (DD/MM/YYYY hh:mm:ss) in UTC * The wind-lidar derived standard deviation of updraft velocities (sigma-w) in m/s, used to apply the parameterization employing a single characteristic velocity (Morales and Nenes, 2010) * The maximum predicted cloud parcel supersaturation (Smax%) * The total in-situ aerosol number concentration (Naer) in cmˉ³, measured by the SMPS * The predicted cloud droplet numbers (Nd) in cmˉ³ * The activation fraction (%)