CHEMICAL CHARACTERISTICS OF RAINWATER
IN BANDUNG AND GAW BUKIT KOTOTABANG
1Fandy
Balbo, S.Si. 2Dr. Rusmawan Suwarman, S.Si., MT.
3Arika Indri Dyah Utami, M.Si.
1Undergraduate
of Departement of Meteorology, Bandung Institute of Technology
2Research Group of Atmosphere Science, Bandung Insitute of Technology
3Center for Applied Climate Information Services, The Indonesia Agency for Meteorological, Climatological, and Geophysics
Background
Departement of Meteorology
Faculty of Earth Science and Technology
Bandung Institute of Technology
Results
Analysis of Variation
 Precipitation is an efficient pathway for removing gases and particles from
atmosphere. Gases incorporated into them are the oxides of Sulphur and
nitrogen, which are chemically converted into sulfuric acid and nitric acid
which are responsible for occurrence of acid rain (Tiwari et al, 2006).
 Two events were recorded acid rain from 28 rain events in urban site
(Kulshresta et al, 2003). Ca2+ acts as a neutralizer and pollutants from local
anthropogenic activities (Khashman, 2008).
 High concentration of SO42- associated with Ca2+ in rural site (Ali, 2005).
 Samples of rainwater can record the chemical processes in atmosphere
and respons to air quality environment problems (Budiwati, 2016).
 Further research is needed in Bandung (urban site) and GAW Bukit
Kototabang (rural site) to determine the pollution and air quality through
the chemical composition of rain water.
• Low precipitation accumulated
in SON (Bandung) induces high
concentration of SO42- and NO3-.
• Anthropogenic activities are not
dependent
on
seasonal
conditions, so that a high
concentration
pollutants
dissolved in low precipitation
(SON).
• Low precipitation accumulated
on DJF ( Bukit Kototabang)
induces
SO42high
concentration.
• The chemical concentration of
rainwater will be lower if the
precipitation increased. Law of
the Dilution Effect applied.
Analysis of Acidity
Bandung
GAW Bukit
Kototabang
2- (%)
SO
nss
4
54.37
61.69
NO3- (%)
45.63
38.04
Relative Contribution
Methods
• Normal rainwater has a pH of 5.6 (slightly acidic). This is
because it is exposed to the carbon dioxide in the
atmosphere. In Bandung, the pH of rainwater below 4.50 while
in Kototabang, pH of rainwater below 4.80.
• The rate of neutralization by Ca2+ (0.32), with FA=0.012 and rate
of neutralization by K+ (1.13), and FA=0.018. Both showed
ineffective neutralization
Mg2+
K+
NH4+
Bandung
Ca2+
0.35
0.04
0.05
0.04
Bukit Kototabang
0.24
0.03
1.13
0.27
NF
• High pollutant concentrations of SO42- and NO3- caused the
rainwater become acidic in Bandung.
Source Identification
• EF Mg2+ and K+ -> Crust.
EFs
Ca2+/Na+ Mg2+/Na+ K+/Na+ Cl-/Na+ SO42-/Na+
Bandung
62.69
1.50
15.58
0.85
46.62
Kototabang
21.70
0.64
132.20 2.57
47.72
EFc
Mg2+/Ca2+ K+/Ca2+
Bandung
0.22
0.25
Kototabang
0.27
6.04
Cl-/Ca2+
114.93
1007.70
SO42-/Ca2+
107.87
318.95
NO3-/Na+
281412.91
183812.47
NO3-/Ca2+
971.66
1833.24
• EF Cl- and Mg2+ -> Sea spray.
• EF SO42- and NO3- indicated high around the sample point.
• Bandung
Factor 1 (Natural Source).
Factor 2 (Local Anthropogenic Source).
Wedge Factor (Long Range Transport Pollutants).
• GAW Bukit Kototabang
Factor 1 (Natural Source) (Long Range Transport Pollutants).
Factor 2 (Local Anthropogenic Source).
Conclusion
• Cations and Anions variations are not affected by seasonal condition. However,
cation and anion concentration strongly influenced by the current precipitation.
Discussion
a)
b)
c)
d)
• Cations are not effective to neutralize the pH value of the rainwater, the value is
still acidic.
• Pollutants in GAW Bukit Kototabang is coming from long-range transport
pollutants. While Bandung’s pollutants are coming from local anthropogenic
activities and long-range transport pollutants.
References
a)
b)
d)
c)
Al-Khashman, O. A. (2008). Chemical characteristics of rainwater collected at a western site of Jordan. Atmospheric
Research .
Budiwati, T., Setyawati, W., dan Tanti, D. A. (2015). Chemical Characteristics of Rainwater in Sumatera, Indonesia,
during 2001-2010. Research
Article.
Hobbs, P. V. (1995). Basic Physical Chemistry for the Atmospheric Science. Cambridge: Cambridge University Press.
Liu, X., dan Kosch-Xhema. (2006). Nitrogen deposition in agroecosystem in the Beijing Area. Agriculture Ecosystems
and Environment.
Kulshrestha, U., Kulshresta, M. J., Sekar, R., Sastry, G., dan Vairamani, M. (2003). Chemical characteristic of rainwater at
an urban site of south- central India. Atmospheric Environment .
Momin, G., Ali, K., Rao, P., Safai, P., Chate, D., dan Praveen, P. (2004). Study of chemical composition of rain water at an
urban (Pune) and a
rural (Sinhagad) location in India. Journal of Geophysical Research.
Samara, C., Tsitourdou, R., dan Balafoutis, C. (1991). Chemical Composition of Rain In Thessaloniki, Greece, In Relation
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Tiwari, S., Ranade, A., dan Singh, D. (2006). Study of chemical species in rainwater at Ballia, a rural environment in
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Xiao, J. (2016). Chemical composition and sources identification of rainwater constituents at an urban site in Xi'an.
Environment Earth Science.
Recomendation
Air quality
management
SO2
purification
from industry
Efective in
dry season
Reduce the
potential acid
rain events