Abstract
Surface seawater was collected using a high-volume water pump in Malaysian waters during the first Prime Scientific Sailing Expedition in 2009 to obtain activity levels of lead-210 (<sup>210</sup>Pb) and polonium-210 (<sup>210</sup>Po). The <sup>210</sup>Pb activity in surface water obtained from this sampling ranged from 0.22 ± 0.06 to 0.96 ± 0.31 mBq/L, averaging 0.58 ± 0.28 mBq/L, whereas the <sup>210</sup>Po activity was between 1.52 ± 0.11 and 8.98 ± 0.96 mBq/L, averaging 4.19 ± 0.58 mBq/L. The <sup>210</sup>Po/<sup>210</sup>Pb activity ratios in the surface water at the studied sites were between 3.48 ± 1.06 and 13.08 ± 3.78, with an average of 7.27 ± 3.73, which is distinctly higher than the range of 0.1 to 2.8 in the whole southern South China Sea and western Pacific regions. The relatively high activities of dissolved <sup>210</sup>Po in Malaysian waters can be attributed to high depositional fluxes of the radionuclides from enhanced dry precipitations caused by haze events. The higher <sup>210</sup>Po fractions found in this study compared with those found in the major oceans were due to terrestrial fires with estimated <sup>210</sup>Po residence times between 0.15 and 0.51 years, slightly less than the 0.2- to 0.8-year residence times found in oceans with higher productivities. Higher residence times have also been observed more often offshore than near the shoreline. This phenomenon results in a slower rate of removal of <sup>210</sup>Po from offshore surface water.
| Original language | English |
|---|---|
| Pages (from-to) | 482-493 |
| Number of pages | 12 |
| Journal | Estuaries and Coasts |
| Volume | 38 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 2014 |
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Keywords
- <sup>210</sup>Pb
- <sup>210</sup>Po
- Haze
- Radionuclides
- Removal rate
- Residence time
- Seawater
ASJC Scopus subject areas
- Aquatic Science
- Ecology, Evolution, Behavior and Systematics
- Ecology
Cite this
High <sup>210</sup>Po Activity Concentration in the Surface Water of Malaysian Seas Driven by the Dry Season of the Southwest Monsoon (June–August 2009). / Sabuti, Asnor Azrin; Mohamed, Che Abd. Rahim.
In: Estuaries and Coasts, Vol. 38, No. 2, 2014, p. 482-493.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - High 210Po Activity Concentration in the Surface Water of Malaysian Seas Driven by the Dry Season of the Southwest Monsoon (June–August 2009)
AU - Sabuti, Asnor Azrin
AU - Mohamed, Che Abd. Rahim
PY - 2014
Y1 - 2014
N2 - Surface seawater was collected using a high-volume water pump in Malaysian waters during the first Prime Scientific Sailing Expedition in 2009 to obtain activity levels of lead-210 (210Pb) and polonium-210 (210Po). The 210Pb activity in surface water obtained from this sampling ranged from 0.22 ± 0.06 to 0.96 ± 0.31 mBq/L, averaging 0.58 ± 0.28 mBq/L, whereas the 210Po activity was between 1.52 ± 0.11 and 8.98 ± 0.96 mBq/L, averaging 4.19 ± 0.58 mBq/L. The 210Po/210Pb activity ratios in the surface water at the studied sites were between 3.48 ± 1.06 and 13.08 ± 3.78, with an average of 7.27 ± 3.73, which is distinctly higher than the range of 0.1 to 2.8 in the whole southern South China Sea and western Pacific regions. The relatively high activities of dissolved 210Po in Malaysian waters can be attributed to high depositional fluxes of the radionuclides from enhanced dry precipitations caused by haze events. The higher 210Po fractions found in this study compared with those found in the major oceans were due to terrestrial fires with estimated 210Po residence times between 0.15 and 0.51 years, slightly less than the 0.2- to 0.8-year residence times found in oceans with higher productivities. Higher residence times have also been observed more often offshore than near the shoreline. This phenomenon results in a slower rate of removal of 210Po from offshore surface water.
AB - Surface seawater was collected using a high-volume water pump in Malaysian waters during the first Prime Scientific Sailing Expedition in 2009 to obtain activity levels of lead-210 (210Pb) and polonium-210 (210Po). The 210Pb activity in surface water obtained from this sampling ranged from 0.22 ± 0.06 to 0.96 ± 0.31 mBq/L, averaging 0.58 ± 0.28 mBq/L, whereas the 210Po activity was between 1.52 ± 0.11 and 8.98 ± 0.96 mBq/L, averaging 4.19 ± 0.58 mBq/L. The 210Po/210Pb activity ratios in the surface water at the studied sites were between 3.48 ± 1.06 and 13.08 ± 3.78, with an average of 7.27 ± 3.73, which is distinctly higher than the range of 0.1 to 2.8 in the whole southern South China Sea and western Pacific regions. The relatively high activities of dissolved 210Po in Malaysian waters can be attributed to high depositional fluxes of the radionuclides from enhanced dry precipitations caused by haze events. The higher 210Po fractions found in this study compared with those found in the major oceans were due to terrestrial fires with estimated 210Po residence times between 0.15 and 0.51 years, slightly less than the 0.2- to 0.8-year residence times found in oceans with higher productivities. Higher residence times have also been observed more often offshore than near the shoreline. This phenomenon results in a slower rate of removal of 210Po from offshore surface water.
KW - <sup>210</sup>Pb
KW - <sup>210</sup>Po
KW - Haze
KW - Radionuclides
KW - Removal rate
KW - Residence time
KW - Seawater
UR - http://www.scopus.com/inward/record.url?scp=84939880747&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84939880747&partnerID=8YFLogxK
U2 - 10.1007/s12237-014-9832-3
DO - 10.1007/s12237-014-9832-3
M3 - Article
VL - 38
SP - 482
EP - 493
JO - Estuaries and Coasts
JF - Estuaries and Coasts
SN - 1559-2723
IS - 2
ER -