Measured ion concentrations and calculated ionisation rates and condensation sink at the SMEAR II station in Hyytiälä, Finland.

********Dataset abstract*******

The authors would appreciate being contacted if the data is used for any purpose.

Ambient cluster and intermediate ion concentrations were measured with the Balanced Scanning Mobility Analyzer (BSMA) at a 10-minute time resolution at the SMEAR II station in Hyytiälä, Finland. Condensation sink values calculated from Differential Mobility Particle Sizer (DMPS) and Aerodynamic Particle Sizer (APS) measurements and ionization rates calculated from gamma and radon measurements as well as modeled cosmic ray radiation. Here we report the 1-hour averaged values for negative and positive ion concentrations at size bins 0.8 - 2 nm, 2 - 4 nm and 4 - 7 nm, condensation sink, gamma ionisation rate and radon ionisation rate as well as monthly cosmic ray ionisation rate values. The data were measured between September 2004 and December 2021.


***********Original data collection***********

The ion concentration data were collected in a container at ground level surround by a Scots pine forest at the SMEAR II station in Hyytiälä, Finland. The DMPS and APS data used in calculating the condensation sink were measured at a ground level cottage about 85 meters from the ion concentration measurement and the gamma and radon measurements were conducted at a separate container about 105 and 50 meters from the ion concentration and aerosol concentraiton measurements, respectively. 


***********Data processing********************

The condensation sink was calculated by using the method from Kulmala et al. (2001, http://dx.doi.org/10.3402/tellusb.v53i4.16622). The gamma and radon ionisation rates were calculatd with the method described in Chen et al. (2016, https://doi.org/10.5194/acp-16-14297-2016) and the cosmic ray ionisation rate with the method described in Usoskin and Kovaltsov (2006, http://dx.doi.org/10.1029/2006JD007150).

************Dataset contents******

Dataset files:
BSMA_negpol.dat (Negative ion concentrations)
BSMA_pospol.dat (Positive ion concentrations)
CosmicRay_Ionisation_Rate.dat (Cosmic Ray ionisation rate)
CS.dat (Condensation sink)
Metadata: METADATA.txt
Gamma_Ionisation_Rate.dat (Gamma ionisation rate)
Radon_Ionisation_Rate.dat (Radon ionisation rate)
Readme: README.txt

**********Dataset contact************

Juha Sulo (juha.sulo@helsinki.fi)


