NISCAIR Online Periodicals Repository

NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR)  >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Geo-Marine Sciences (IJMS) >
IJMS Vol.33 [2004] >
IJMS Vol.33(1) [March 2004] >


Title: Atmospheric deposition fluxes of ⁷Be, ²¹⁰Pb and chemical species to the Arabian Sea and Bay of Bengal
Authors: Rengarajan, R
Sarin, M M
Keywords: Arabian Sea
Bay of Bengal
Aerosol composition
Atmospheric deposition fluxes chemical species
Be
Pb
Nuclides
Issue Date: Mar-2004
Publisher: CSIR
IPC CodeInt. Cl. ⁷ C09K3/30
Abstract: Aerosol samples collected close to the air-sea interface, between February 1997 to February 1999, over the Arabian Sea and Bay of Bengal were analyzed to determine the atmospheric dry-deposition of Fe (dust inputs), anthropogenic constituents (NO₃⁻, SO₄²⁻) and environmental nuclides (⁷Be, ²¹⁰Pb). In general, aerosol ²¹⁰Pb concentrations showed a good correlation with ⁷Be, suggesting the long-range transport of ²¹⁰Pb from the continents (via upper troposphere) and similarities in the processes governing their deposition through the marine boundary layer (MBL). The relatively low ⁷Be/²¹⁰Pb ratios observed over the Bay of Bengal, during February 1999, are dominated by aerosol transport from the continental surface sources. The dry deposition fluxes of ²¹⁰Pb and ⁷Be, to these two oceanic regions, average around 245 and 1860 Bq m⁻² y⁻¹, respectively. The non-sea-salt (nss) SO₄²⁻ (range: 1.7 to 9.4 µg m⁻³) and NO₃⁻ (range: 0.6 to 4.1 μg m⁻³) are uncorrelated in the MBL, presumably because continental pollution sources for SO₄²⁻ overwhelm the transport of NO₃⁻ from crustal dust and biomass burning. The oceanic biogenic emission (DMS) constitutes a very minor source for nss-SO₄²⁻. The enhanced concentrations of aerosol NO₃⁻ and Fe observed over the Arabian Sea are attributed to dust storm activities from the adjacent desert areas (Saudi Arabia and Thar). Significant scatter in the linear regression analyses indicate that the aerosol composition along the coastal tracks is different from those transported to the open ocean. On average, dry deposition fluxes of N-NO₃ and non-marine SO₄²⁻ are 150 and 1225 mg m⁻² y⁻¹, respectively. In contrast, dry deposition of Fe over the Arabian Sea (255 mg m⁻² y⁻¹) far exceeds that over the Bay of Bengal (93 mg m⁻² y⁻¹). Thus, dust from desert regions appears to be a potential source of micronutrients (Fe) to the surface Arabian Sea.
Page(s): 56-64
ISSN: 0379-5136
Source: IJMS Vol.33(1) [March 2004]

Files in This Item:

File Description SizeFormat
IJMS 33(1) 56-64.pdf324.21 kBAdobe PDFView/Open
 Current Page Visits: 652 
Recommend this item

 

National Knowledge Resources Consortium |  NISCAIR Website |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2012 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 621839 since 06-Feb-2009  Last updated on 13-Nov-2014Webmaster: nopr@niscair.res.in