Rapid invasion of anthropogenic CO2 into the deep circulation of the Weddell Gyre

Data are presented for total carbon dioxide (TCO2), oxygen and nutrients from 14 cruises covering two repeat sections across the Weddell Gyre, from 1973 to 2010. Assessments of the rate of increase in anthropogenic CO2 (Cant) are made at three locations. Along the Prime Meridian, TCO2 is observed to steadily increase in the bottom water. Accompanying changes in silicate, nitrate and oxygen confirm the non-steady state of the Weddell circulation. The rate of increase in TCO2 of +0.12±0.05?µmol?kg-1?yr-1 therefore poses an upper limit to the rate of increase in Cant. By contrast, the bottom water located in the central Weddell Sea exhibits no significant increase in TCO2, suggesting that this water is less well ventilated at the southern margins of the Weddell Sea. At the tip of the Antarctic Peninsula (i.e. the formation region of the bottom water found at the Prime Meridian), the high rate of increase in TCO2 over time observed at the lowest temperatures suggests that nearly full equilibration occurs with the anthropogenic CO2 of the atmosphere. This observation constitutes rare evidence for the possibility that ice cover is not a major impediment for uptake of Cant in this prominent deep water formation region

Quantification of chemical and mechanical bioerosion rates of six Caribbean excavating sponge species found on the coral reefs of Curaçao

Excavating sponges are among the most important macro-eroders of carbonate substrates in marine systems. Their capacity to remove substantial amounts of limestone makes these animals significant players that can unbalance the reef carbonate budget of tropical coral reefs. Nevertheless, excavating sponges are currently rarely incorporated in standardized surveys and experimental work is often restricted to a few species. Here were provide chemical and mechanical bioerosion rates for the six excavating sponge species most commonly found on the shallow reef of Curaçao (southern Caribbean): Cliona caribbaea, C. aprica, C. delitrix, C. amplicavata, Siphonodictyon brevitubulatum and Suberea flavolivescens. Chemical, mechanical and total bioerosion rates were estimated based on various experimental approaches applied to sponge infested limestone cores. Conventional standing incubation techniques were shown to strongly influence the chemical dissolution signal. Final rates, based on the change in alkalinity of the incubation water, declined significantly as a function of incubation time. This effect was mitigated by the use of a flow-through incubation system. Additionally, we found that mechanically removed carbonate fragments collected in the flow-through chamber (1 h) as well as a long-term collection method (1 wk) generally yielded comparable estimates for the capacity of these sponges to mechanically remove substratum. Observed interspecific variation could evidently be linked to the adopted boring strategy (i.e. gallery-forming, cavity-forming or network-working) and presence or absence of symbiotic zooxanthellae. Notably, a clear diurnal pattern was found only in species that harbour a dense photosymbiotic community. In these species chemical erosion was substantially higher during the day. Overall, the sum of individually acquired chemical and mechanical erosion using flow-through incubations was comparable to rates obtained gravimetrically. Such consistency is a first in this field of research. These findings support the much needed confirmation that, depending on the scientific demand, the different approaches presented here can be implemented concurrently as standardized methods

South Atlantic Interbasin Exchanges of Mass, Heat, Salt and Anthropogenic Carbon

The exchange of mass, heat, salt and anthropogenic carbon (Cant) between the South Atlantic, south of 24°S, and adjacent ocean basins is estimated from hydrographic data obtained during 2008-2009 using an inverse method. Transports of anthropogenic carbon are calculated across the western (Drake Passage), eastern (30°E) and northern (24°S) boundaries. The freshwater overturning transport of 0.09 Sv is southward, consistent with an overturning circulation that exports freshwater from the North Atlantic, and consistent with a bistable Meridional Overturning Circulation (MOC), under conditions of excess freshwater perturbation. At 30°E, net eastward Antarctic Circumpolar Current (ACC) transport, south of the Subtropical Front, is compensated by a 15.9±2.3 Sv westward flow along the Antarctic boundary. The region as a whole is a substantial sink for atmospheric anthropogenic carbon of 0.51±0.37 PgC yr-1, of which 0.18±0.12 PgC yr-1 accumulates and is stored within the water column. At 24°S, a 20.2 Sv meridional overturning is associated with a 0.11 PgC yr-1 Cant overturning. The remainder is transported into the Atlantic Ocean north of 24°S (0.28±0.16 PgC yr-1) and Indian sector of Southern Ocean (1.12±0.43 PgC yr-1), having been enhanced by inflow through Drake Passage (1.07±0.44 PgC yr-1). This underlines the importance of the South Atlantic as a crucial element of the anthropogenic carbon sink in the global oceans

Ocean Salinity, Major Elements, and Thermohaline Circulation

Ocean geochemistry is the discipline focusing mostly on the inorganic constituents of seawater in the world oceans. Interactions with biology and organic chemistry, and external sources and sinks, such as rivers, atmosphere, hydrothermal vents, and sediments, do play a role. Marine geochemistry comprises a far wider range including other aspects of inorganic geochemistry and organic geochemistry, and secondly not only the seawater but also investigations focusing on the underlying marine sediments and their inorganic and organic contents

Surface underway measurements of pCO2, temperature, salinity and other variables collected during the R/V Polarstern cruises in 2017 (NCEI Accession 0170287)

This NCEI Accession includes surface underway, chemical and meteorological data collected from R/V Polarstern in the North Atlantic Ocean, South Atlantic Ocean, South Pacific Ocean and Southern Oceans from 2017-02-05 to 2017-10-13. These data include partial pressure (or fugacity) of carbon dioxide - atmosphere, partial pressure (or fugacity) of carbon dioxide - water, sea surface temperature, sea surface salinity, barometric pressure, wind speed and direction. The instruments used to collect these data include Carbon dioxide (CO2) gas analyzer and shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement. These data were collected by Mario Hoppema of Alfred Wegener Institute for Polar and Marine Research and Steven van Heuven of Groningen University

Rapid acidification of mode and intermediate waters in the southwestern Atlantic Ocean

Observations along the southwestern Atlantic WOCE A17 line made during the Dutch GEOTRACESNL programme (2010-2011) were compared with historical data from 1994 to quantify the changes in the anthropogenic component of the total pool of dissolved inorganic carbon (Delta C-ant). Application of the extended multilinear regression (eMLR) method shows that the Delta C-ant from 1994 to 2011 has largely remained confined to the upper 1000 dbar. The greatest changes occur in the upper 200 dbar in the Subantarctic Zone (SAZ), where a maximum increase of 37 mu mol kg(-1) is found. South Atlantic Central Water (SACW) experienced the highest rate of increase in C-ant, at 0.99 +/- 0.14 mu mol kg(-1) yr(-1), resulting in a maximum rate of decrease in pH of 0.0016 yr(-1). The highest rates of acidification relative to Delta C-ant, however, were found in Subantarctic Mode Water (SAMW) and Antarctic Intermediate Water (AAIW). The low buffering capacity of SAMW and AAIW combined with their relatively high rates of C-ant increase of 0.53 +/- 0.11 and 0.36 +/- 0.06 mu mol kg(-1) yr(-1), respectively, has lead to rapid acidification in the SAZ, and will continue to do so whilst simultaneously reducing the chemical buffering capacity of this significant CO2 sink

A Comparative US and EU Perspective on the Japanese Antimonopoly Law\u27s Leniency Program

1. INTRODUCTION 2. THE FEATURES OF THE JAPANESE LEMENCY PROGRAM 3. EVALUATING LENIENCY PROGRAMS 3.1. A Game of Strategic Rational Behavior 3.2. Information in Function of a Leniency Program 4. LENIENCY FOR THE PRE-AND POST-INVESTIGATION STAGE 4.1. Few Lessons from Practice 4.2. Leniency beyond the Pre-Investigation Stage in Japan 5. IMMUNITY As AN INCENTIVE 5.1. Immunity, only for the Pre-investigation Stage? 5.2. Japan Thrifty with Immunity 6. A RACE TO THE COURTHOUSE DOOR 6.1. Limiting Leniency to the First Applicant? 6.2. A Race to Kasumigaseki? 7. THE ABSENCE OF DISCRETIONARY POWERS 7.1. Immunity or Not, That is the Question 7.2. Immunity or Reduction, That is the Question 7.3. Discretion or Not, That is the Question in Japan 8. CLEAR CONDITIONS FOR QUALIFICATION 8.1. A Forgotten Aspect of Leniency Programs 8.2. 0verview of Conditions 8.3. Problematic Conditions 8.4. Short and Clear Conditions in Japan 9. CONCLUSIO

The relationship between cadmium and phosphate in the Atlantic Ocean unravelled

Cadmium (Cd) is not generally considered a nutrient element, but behaves like a nutrient in the oceans and might play an important role in ocean biology after all. The relationship between Cd and the nutrient phosphate (PO₄) has been studied for over 40 yrs, but the debate on the driving mechanism and reason behind the ‘kink’, a change in the steepness of the slope is ongoing. Using new data of high accuracy and spatial resolution covering the West-Atlantic Ocean from north to south, in combination with a robust extended optimum multiparameter (eOMP) water mass model, we show that mixing between different water masses is the dominant factor explaining the observed correlation and its kink. Regeneration of Cd via remineralisation explains the smaller scale variability, notably in the surface ocean. Observations imply the availability of Cd in surface waters determines the Cd-uptake and thus the Cd:PO₄ remineralisation ratio. This ratio is variable between different ocean regions, notably between the northern and southern high latitude oceans. Due to their role in deep water formation, both the northern and southern high latitude oceans are a driving factor in the Atlantic and global Cd and PO₄ relation. Outside the Atlantic Ocean, the classical kink is not expected, but the relationship is by no means linear. Most likely, this is due to the interaction between low latitude surface waters and subsurface waters from high latitude origin, but more data are required to assess this in detail

Quantification of chemical and mechanical bioerosion rates of six Caribbean excavating sponge species found on the coral reefs of Curaçao

Excavating sponges are among the most important macro-eroders of carbonate substrates in marine systems. Their capacity to remove substantial amounts of limestone makes these animals significant players that can unbalance the reef carbonate budget of tropical coral reefs. Nevertheless, excavating sponges are currently rarely incorporated in standardized surveys and experimental work is often restricted to a few species. Here were provide chemical and mechanical bioerosion rates for the six excavating sponge species most commonly found on the shallow reef of Curaçao (southern Caribbean): Cliona caribbaea, C. aprica, C. delitrix, C. amplicavata, Siphonodictyon brevitubulatum and Suberea flavolivescens. Chemical, mechanical and total bioerosion rates were estimated based on various experimental approaches applied to sponge infested limestone cores. Conventional standing incubation techniques were shown to strongly influence the chemical dissolution signal. Final rates, based on the change in alkalinity of the incubation water, declined significantly as a function of incubation time. This effect was mitigated by the use of a flow-through incubation system. Additionally, we found that mechanically removed carbonate fragments collected in the flow-through chamber (1 h) as well as a long-term collection method (1 wk) generally yielded comparable estimates for the capacity of these sponges to mechanically remove substratum. Observed interspecific variation could evidently be linked to the adopted boring strategy (i.e. gallery-forming, cavity-forming or network-working) and presence or absence of symbiotic zooxanthellae. Notably, a clear diurnal pattern was found only in species that harbour a dense photosymbiotic community. In these species chemical erosion was substantially higher during the day. Overall, the sum of individually acquired chemical and mechanical erosion using flow-through incubations was comparable to rates obtained gravimetrically. Such consistency is a first in this field of research. These findings support the much needed confirmation that, depending on the scientific demand, the different approaches presented here can be implemented concurrently as standardized methods