Carbon dioxide, hydrographic, and chemical data obtained during the R/V Meteor Cruise 22/5 in the South Atlantic Ocean (WOCE Section A10, December 1992--January 1993)

This documentation discusses the procedures and methods used to measure total carbon dioxide (TCO{sub 2}), total alkalinity at Hydrographic stations as well as the underway partial pressure of CO{sub 2} (pCO{sub 2}) during the R/V Meteor Cruise M22/5 in the South Atlantic Ocean (Section A10). Conducted as part of the World Ocean Circulation Experiment (WOCE), the cruise began in Rio de Janeiro on 27 December 1992, and ended after 36 days at sea in Capetown, South Africa on 31 January 1993. Instructions for accessing the data are provided. TCO{sub 2} was measured using tow automated sample processors for extracting CO{sub 2} from seawater samples which were coupled to a Coulometer for detection of the extracted CO{sub 2}. The overall precision and accuracy of the analyses was {+-} 1.9 {micro}mol/kg. Samples collected for total alkalinity were measured by potentiometric titration; precision was {+-} 2.0 {micro}mol/kg. Underway pCO{sub 2} was measured by Infra Red (IR) Photometry; precision was {+-} 2.0 {micro}atm. From these cruises the large-scale three-dimensional distribution of temperature, salinity, and chemical constituents, including the carbonate system parameters will be mapped. Knowledge of these parameters and their initial conditions will allow determination of heat and water transports as well as carbon transport. An understanding of these transports will contribute to the understanding of processes which are relevant for climate change. This section in the South Atlantic subtropical Gyre is especially relevant for CO{sub 2} transport because it crosses both the Brazil and the Benguela Boundary Currents

Sensors and instruments for oceanic dissolved carbon measurements

Highly accurate and precise measurements of marine carbon components are required in the study of the marine carbon cycle, particularly when investigating the causes for its variability from seasonal to interannual timescales. This is especially true in the investigation of the consequences of anthropogenic influences. <br><br> The analysis of any marine carbon component requires elaborate instrumentation, most of which is currently used onboard ships, either in manual or automated mode. Technological developments result in more and more instruments that have sufficient long-term reliability so that they can be deployed on commercial ships, surface moorings, and buoys, whilst the great technological and operational challenges mean that only few sensors have been developed that can be used for sub-surface in situ measurements on floats, robots, or gliders. There is a special need for autonomous instruments and sensors that are able to measure a combination of different components, in order to increase the spatial and temporal coverage of marine carbon data. <br><br> This paper describes analytical techniques used for the measurement of the marine dissolved carbon components, both inorganic and organic: the fugacity of CO<sub>2</sub>, total dissolved inorganic carbon, pH, alkalinity, and dissolved organic carbon. By pointing out advantages, disadvantages, and/or challenges of the techniques employed in the analysis of each component, we aim to aid non-carbon marine scientists, sensor developers and technologists, in the decision of which challenges to address in further development

Carbon dioxide, hydrographic, and chemical data obtained during the R/V Meteor Cruise 18/1 in the North Atlantic Ocean (WOCE Section A1E, September 1991)

The North Atlantic Ocean is characterized by an intense meridional circulation cell carrying near-surface waters of tropical and subtropical origin northward and deep waters of arctic and subarctic origin southward. The related {open_quotes}overturning{close_quotes} is driven by the sinking of water masses at high latitudes. The overturning rate and thus the intensity of the meridional transports of mass, heat, and salt, is an important control parameter for the modeling of the ocean`s role in climate. The Research Vessel (R/V) Meteor Cruise 18/1 was one in a series of cruises in the North Atlantic that started in March 1991 and continued until 1995. This data documentation discusses the procedures and methods used to measure total carbon dioxide (TCO{sub 2}) and total alkalinity (TALK) at hydrographic stations, as well as underway partial pressure of CO{sub 2} (pCO{sub 2}) measured during the RIV Meteor Cruise 18/1 in the North Atlantic Ocean (Section A1E). Conducted as part of the World Ocean Circulation Experiment (WOCE) and the German North Atlantic Overturning Rate Determination expedition, the cruise began in Reykjavik, Iceland, on September 2, 1991, and ended after 24 days at sea in Hamburg, Germany, on September 25, 1991. WOCE Zonal Section AlE began at 60{degrees}N and 42{degrees}30{prime} W (southeast of Greenland) and continued southeast with a closely spaced series of hydrocasts to 52{degrees}20{prime} N and 14{degrees}15{prime} W (Porcupine Shelves). Measurements made along WOCE Section AlE included pressure, temperature, salinity, and oxygen measured by a conductivity, temperature and depth (CTD) sensor; bottle salinity; oxygen; phosphate; nitrate; nitrite; silicate; TCO{sub 2}; TALK; and underway pCO{sub 2}. A total of 61 CTD casts were made, including 59 bottle casts and 2 calibration stations

The CO2 system in the Mediterranean Sea: a basin wide perspective.

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Natürliche Senken und Quellen des atmosphärischen Kohlendioxids: Stand des Wissens und Optionen des Handelns

Die Dynamik des globalen Kohlenstoffkreislaufs bestimmt den Zusammenhang zwischen Emissionen von Kohlendioxid und der daraus resultierenden Zunahme der atmosphärischen Konzentration des CO2. Die Studie erläutert den zur Zeit vorliegenden Kenntnisstand der für diese Dynamik entscheidenden Austauschprozesse zwischen und innerhalb der auf Zeitskalen von bis zu einigen 100 Jahren relevanten Kohlenstoffspeichem Atmosphäre, Ozean und terre- strische Biosphäre. Aufbauend auf diesem Systemverständnis werden dann Möglichkeiten dis- kutiert, auf die natürlichen Quellen- und Senkenprozesse einzuwirken, um damit CO2- Emissionen zu vermeiden, respektive CO2-Senken zu verstärken. Die Bewertung der im ein- zelnen dargestellten Optionen erfolgt dabei auf der Basis der globalen Kohlenstoffbilanz, d.h. ob damit ein signifikanter Beitrag zur globalen CO2-Problematik geleistet werden könnte. Die Studie zeigt, daß in den meisten Fällen der vorhandene Kenntnisstand leider nicht aus- reicht, um die Auswirkungen einzelner Optionen in ihrer globalen Wirksamkeit abschließend zu bewerten. Dennoch läßt sich der Effekt einzelner Einwirkungsmöglichkeiten abschätzen: Demnach könnte im marinen Bereich einzig die direkte Verklappung von COS in die Tiefsee einen signifikanten Beitrag liefern. Selbst unter optimistischen Annahmen besitzen andere Möglichkeiten, wie Eisendüngung, Anbau von Makroalgen, nur ein marginales Potential für eine zusätzliche, langfristige Speicherung von Überschuß-CO2. Auf der terrestrischen Seite bieten nur die großflächige Aufforstung sowie die Einführung nachhaltiger Wirtschaftsweisen in der Landnutzung, insbesondere in der dritten Welt, ein re- lativ bescheidenes Potential für die Entfernung von COS aus der Atmosphäre. In der Studie wird im weiteren der Forschungsbedarf skizziert, welcher notwendig ist, um die Unsicherheiten einzuschränken, welche bezüglich Prozeßverständnis, regionaler und globaler Quantifizierung sowie Darstellung des globalen Kohlenstoffkreislaufs mit Hilfe von Simulati- onsmodellen bestehen

When assessment defines the content—understanding goals in between teachers and policy

© 2020 The Authors. The Curriculum Journal published by John Wiley & Sons Ltd on behalf of British Educational Research Association.Education policy development internationally reflect a widespread expansion of learning outcome orientation in policy, curricula and assessment. In this paper, teachers’ perceptions about their work are explored, as goals and assessment play a more prominent role driven by the introduction of a learning outcomes‐oriented system. This is investigated through interviews of Norwegian teachers and extensive policy analysis of Norwegian policy documents. The findings indicate that the teachers are finding ways to negotiate and adjust to the language in the policies investigated in this study. Furthermore, the findings show that the teachers have developed their professional language according to the policies. The teachers referred to their self‐made criteria and goal sheets as central tools in explicating what is to be learned. In many ways, the tools for assessment, thus determine the content of education as well as what is valued in the educational system.publishedVersio

A revised nitrogen budget for the Arabian Sea

Despite its importance for the global oceanic nitrogen (N) cycle, considerable uncertainties exist about the N fluxes of the Arabian Sea. On the basis of our recent measurements during the German Arabian Sea Process Study as part of the Joint Global Ocean Flux Study (JGOFS) in 1995 and 1997, we present estimates of various N sources and sinks such as atmospheric dry and wet depositions of N aerosols, pelagic denitrification, nitrous oxide (N2O) emissions, and advective N input from the south. Additionally, we estimated the N burial in the deep sea and the sedimentary shelf denitrification. On the basis of our measurements and literature data, the N budget for the Arabian Sea was reassessed. It is dominated by the N loss due to denitrification, which is balanced by the advective input of N from the south. The role of N fixation in the Arabian Sea is still difficult to assess owing to the small database available; however, there are hints that it might be more important than previously thought. Atmospheric N depositions are important on a regional scale during the intermonsoon in the central Arabian Sea; however, they play only a minor role for the overall N cycling. Emissions of N2O and ammonia, deep-sea N burial, and N inputs by rivers and marginal seas (i.e., Persian Gulf and Red Sea) are of minor importance. We found that the magnitude of the sedimentary denitrification at the shelf might be ∼17% of the total denitrification in the Arabian Sea, indicating that the shelf sediments might be of considerably greater importance for the N cycling in the Arabian Sea than previously thought. Sedimentary and pelagic denitrification together demand ∼6% of the estimated particulate organic nitrogen export flux from the photic zone. The main northward transport of N into the Arabian Sea occurs in the intermediate layers, indicating that the N cycle of the Arabian Sea might be sensitive to variations of the intermediate water circulation of the Indian Ocean

Mintrop, Heinwich, and Gail L. Sunderman, Predictable Failure of Federal Sanctions-Driven Accountability for School Improvement -- And Why We May Retain It Anyway, Educational Researcher, 38(june/July,2009), 353-364.

Summarizes results of studies on three questions: 1) Do sanctions-driven accountability systems produce the intended results in NCLB and other attempts? 2) Is it practical and can it be implemented? 3) Is it valued and legitimate