Seasonal Dynamics of Dissolved Iron on the Antarctic Continental Shelf: Late‐Fall Observations From the Terra Nova Bay and Ross Ice Shelf Polynyas

Abstract

The biological consumption of nutrients from waters of the "lower cell" of the meridional overturning circulation that upwell south of the Antarctic Polar Front exerts an important control on the ocean-atmosphere balance of carbon dioxide (

Dissolved, Labile, and Total Particulate Trace Metal Dynamics on the Northeast Greenland Shelf

“…Similarly in austral autumn, Sedwick et al. (2022) found no clear evidence of dFe enrichments associated with ice melting. They did however discover similar distributions of dFe, pFe, pMn, and pAl, again supporting a major role for suspended sediment particles in regulating TM dynamics.…”

Biological Uptake, Water Mass Mixing and Scavenging Limit the Transport of Manganese‐Rich Waters From the East Antarctic Shelf

“…(2013) in the Weddell Sea and Sedwick et al. (2022) in the Ross Sea. In the Weddell Sea, we used 0.78 nmol kg −1 as Mn source (shelf bottom value) and 0.19 nmol kg −1 as Mn offshore (average dMn in Weddell Sea Bottom Water, Table 1 from Middag et al., 2013), and calculated a 76.3% removal term.…”

“…In the Ross Sea, we calculated a removal of 73.3%, using a Mn source of 1.06 ± 0.1 nmol kg −1 ( n = 4), averaged from datapoints within shelf waters at station 9 of Sedwick et al. (2022) and a Mn offshore of 0.28 ± 0.1 nmol kg −1 ( n = 10), averaged across our AABW points along transect 150. Both these removal terms are close to the calculated value (76.3%) of this study.…”

“…In the Weddell Sea, we used 0.78 nmol kg −1 as Mn source (shelf bottom value) and 0.19 nmol kg −1 as Mn offshore (average dMn in Weddell Sea Bottom Water, Table 1 from Middag et al, 2013), and calculated a 76.3% removal term. In the Ross Sea, we calculated a removal of 73.3%, using a Mn source of 1.06 ± 0.1 nmol kg −1 (n = 4), averaged from datapoints within shelf waters at station 9 of Sedwick et al (2022) and a Mn offshore of 0.28 ± 0.1 nmol kg −1 (n = 10), averaged across our AABW points along transect 150. Both these removal terms are close to the calculated value (76.3%) of this study.…”

“…Hence, pMn may influence dMn scavenging before settling to the seafloor and we expect the rates of passive adsorption onto particles will equilibrate as bottom waters age. For comparison with other regions producing AABW, we calculated the dMn removal term (Equation 2) applied to the data set of Middag et al (2013) in the Weddell Sea and Sedwick et al (2022) in the Ross Sea. In the Weddell Sea, we used 0.78 nmol kg −1 as Mn source (shelf bottom value) and 0.19 nmol kg −1 as Mn offshore (average dMn in Weddell Sea Bottom Water, Table 1 from Middag et al, 2013), and calculated a 76.3% removal term.…”