Identification

Title

Basic characteristics of atmospheric particles, trace gases and meteorology in a relatively clean Southern African Savannah environment

Abstract

We have analyzed one year (July 2006-July 2007) of measurement data from a relatively clean background site located in dry savannah in South Africa. The annual-median trace gas concentrations were equal to 0.7 ppb for SO₂, 1.4 ppb for NOx, 36 ppb for O₃ and 105 ppb for CO. The corresponding PM₁, PM₂.₅ and PM₁₀ concentrations were 9.0, 10.5 and 18.8 μg m⁻³, and the annual median total particle number concentration in the size range 10–840 nm was 2340 cm⁻³. During Easterly winds, influence of industrial sources approximately 150 km away from the measurement site was clearly visible, especially in SO2 and NOx concentrations. Of gases, NOx and CO had a clear annual, and SO2, NOx and O3 clear diurnal cycle. Atmospheric new-particle formation was observed to take place in more than 90% of the analyzed days. The days with no new particle formation were cloudy or rainy days. The formation rate of 10 nm particles varied in the range of 0.1–28 cm⁻³ s⁻¹ (median 1.9 cm⁻³ s⁻¹) and nucleation mode particle growth rates were in the range 3–21 nm h⁻¹ (median 8.5 nm h⁻¹). Due to high formation and growth rates, observed new particle formation gives a significant contribute to the number of cloud condensation nuclei budget, having a potential to affect the regional climate forcing patterns.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7d50n64

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2008-08-19T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Copyright Author(s) 2008. This work is distributed under the Creative Commons Attribution 3.0 License.

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata date

2025-12-26T15:16:31.203776

Metadata language

eng; USA