Details for Coastal iodine emissions: Part 1. Release of I2 by Laminaria digitata in chamber experiments

PropertyValue
Name:Coastal iodine emissions: Part 1. Release of I2 by Laminaria digitata in chamber experiments
Description:

Ashu-Ayem, E.R., U, Nitschke, C. Monahan, J. Chen, S.B. Darby, P.D. Smith, C.D. O’Dowd, D. B. Stengel, D.S. Venables. Coastal iodine emissions: Part 1. Release of I2 by Laminaria digitata in chamber experiments, dx.doi.org/10.1021/es204534v | Environ. Sci. Technol. 2012, 46, 10413−10421.


Abstract. Tidally exposed macroalgae emit large amounts of I2 and iodocarbons that produce hotspots of iodine chemistry and intense particle nucleation events in the coastal marine boundary layer. Current emission rates are poorly characterized, however, with reported emission rates varying by 3 orders of magnitude. In this study, I2 emissions from 25 Laminaria digitata samples were investigated in a simulation chamber using incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS). The chamber design allowed gradual extraction of seawater to simulate tidal emersion of algae. Samples were exposed to air with or without O3 and to varying irradiances. Emission of I2 occurred in four distinct stages: (1) moderate emissions from partially submerged samples; (2) a strong release by fully emerged samples; (3) slowing or stopping of I2 release; and (4) later pulses of I2 evident in some samples. Emission rates were highly variable and ranged from 7 to 616 pmol min1 gFW1 in ozone-free air, with a median value of 55 pmol min1 gFW1 for 20 samples.

 

Filename:EST_Coastal Iodine Emissions_Part 1_Ashu-Ayem et al.pdf
Filesize: 3.16 MB
Filetype:pdf (Mime Type: application/pdf)
Creator:SGJ
Created On: 03/19/2013 15:59
Viewers:Everybody
Maintained by:Editor
Hits:834 Hits
Last updated on: 03/19/2013 16:02
Homepage: