Estimation of reactive inorganic iodine fluxes in the Indian and Southern Ocean marine boundary layer

Iodine chemistry has noteworthy impacts on the oxidising capacity of the marine boundary layer (MBL) through the depletion of ozone (O3) and changes to HOx (OH=HO2) and NOx (NO=NO2) ratios. Hitherto, studies have shown that the reaction of atmospheric O3 with surface seawater iodide (I-) contributes to the flux of iodine species into the MBL mainly as hypoiodous acid (HOI) and molecular iodine (I2). Here, we present the first concomitant observations of iodine oxide (IO), O3 in the gas phase, and sea surface iodide concentrations. The results from three field campaigns in the Indian Ocean and the Southern Ocean during 2015 2017 are used to compute reactive iodine fluxes in the MBL. Observations of atmospheric IO by multi-axis differential optical absorption spectroscopy (MAX-DOAS) show active iodine chemistry in this environment, with IO values up to 1 pptv (parts per trillion by volume) below latitudes of 40° S. In order to compute the sea-to-air iodine flux supporting this chemistry, we compare previously established global sea surface iodide parameterisations with new regionspecific parameterisations based on the new iodide observations. This study shows that regional changes in salinity and sea surface temperature play a role in surface seawater iodide estimation. Sea air fluxes of HOI and I2, calculated from the atmospheric ozone and seawater iodide concentrations (observed and predicted), failed to adequately explain the detected IO in this region. This discrepancy highlights the need to measure direct fluxes of inorganic and organic iodine species in the marine environment. Amongst other potential drivers of reactive iodine chemistry investigated, chlorophyll a showed a significant correlation with atmospheric IO (R D 0:7 above the 99 % significance level) to the north of the polar front. This correlation might be indicative of a biogenic control on iodine sources in this region

Humic acids from an Arctic fjord, Krossfjorden, Spitsbergen

Humic substances are ubiquitous materials found in terrestrial and aquatic ecosystems. Humic acids, a diagenetic product can interact with various components present in aquatic sediments. The present research is on the evaluation of sedimentary humic acids from the Krossfjorden glacial fjord situated within the Svalbard archipelago. The results of this study are needed to understand the structural characteristics of humic acids isolated from the fjord. Surface sediment samples were collected from four stations throughout the fjord during a summer period in 2018. Various spectroscopic techniques such as UV-visible, Fourier-transform infrared spectroscopy (FTIR), and Nuclear magnetic resonance spectroscopy (NMR) were applied for studying the humic acids. The elemental composition as well as the presence of tannin and lignin were also analyzed. The results of this study revealed the variation in the structure of humic acids from aliphatic to aromatic from the outer to the inner region of the fjord. This change in humic acids was well supported by the FTIR and NMR results with differences in the spectrums

Abstracts of Scientifica 2022

This book contains the abstracts of the papers presented at Scientifica 2022, Organized by the Sancheti Institute College of Physiotherapy, Pune, Maharashtra, India, held on 12–13 March 2022. This conference helps bring researchers together across the globe on one platform to help benefit the young researchers. There were six invited talks from different fields of Physiotherapy and seven panel discussions including over thirty speakers across the globe which made the conference interesting due to the diversity of topics covered during the conference. Conference Title:  Scientifica 2022Conference Date: 12–13 March 2022Conference Location: Sancheti Institute College of PhysiotherapyConference Organizer: Sancheti Institute College of Physiotherapy, Pune, Maharashtra, Indi