56 research outputs found
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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
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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
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 bridge between worlds: understanding network structure to understand change strategy
A number of scholars are exploring district and site relations in organizational change efforts in the larger policy context of No Child Left Behind. These studies suggest the importance of the central office as a support to the work of reform and offer strategies for building relations between district offices and sites in order to implement and sustain change efforts. What is frequently overlooked in these studies is that organizational change efforts are often socially constructed. Therefore, examining the underlying social networks may provide insight into structures that support or constrain efforts at change. This exploratory case study uses social network analysis and interviews to examine the communication and knowledge network structures of central office and site leaders in an ‘in need of improvement’ district facing sanctions under No Child Left Behind. Findings indicate sparse ties among and between school site and central office administrators, as well as a centralized network structure that may constrain the exchange of complex information and ultimately inhibit efforts at change
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Carbon dioxide, hydrographic, and chemical data from the F/S Meteor Cruise No. 18 in the North Atlantic Ocean (WOCE Section A1/E) during September 1991
This report presents the procedures and methods used to obtain total carbon dioxide (C{sub T}), total alkalinity, and underway pCO{sub 2} data during the F/S Meteor Cruise 18 in the North Atlantic Ocean (WOCE Section A1/E). The F/S Meteor departed Reykjavik on September 2, 1991 and docked in Hamburg early on the morning of September 25, 1991 after 24 days at sea. A two day steam from Reykjavik brought the ship to the starting position for WOCE zonal section A1/east (A1/E) on September 5. Section work began and ended with a closely spaced series hydrocasts on the SE-Greenland (60{degree}N 42{degree}30 minutes W) and Porcupine Shelves (52{degree}20 minutes N 14{degree}15 minutes W), respectively. The cast schedule was interrupted for equipment problems (6 and 7 September), current meter deployments (9, 10, 11, 14, and 19 September), and by high seas (13, 14, and 17 September). Of 64 CTD casts made, 58 were bottle casts including two calibration stations. Measurements made included CTD pressure, temperature, salinity, bottle salinity, oxygen, phosphate, nitrate, nitrite, silicate, total alkalinity, CFC`S, total carbon dioxide, and continuous underway pCO{sub 2} of surface waters. Carbonate samples were collected from 31 section stations (55.4% of the section stations), one test station, and two calibration stations. Repeated XBT, and ADCP profiles were taken throughout the cruise. Instructions for accessing the data are provided
Die Steuerfunktion des Karbonatsystems fuer die CO_2-Aufnahme durch den Ozean Abschlussbericht
The project 'Control function of the carbonate system over oceanic CO_2 absorption' included six expeditions into the Atlantic Ocean between June 1990 and February 1993 where the parameters of the carbonate system, namely CO_2 partial pressure, total carbonate concentation, and alkalinity, and further parameters such as salinity, temperature, nutrient salts, and chlorophyll concentration were measured. It proved possible to elaborate from these data a picture of the partial pressure distribution in the surface water of the Atlantic, which is the driving force of the CO_2 exchange with the atmosphere, and of its spatial and temperol variability. Furthermore, the relative weight of the various influence factors was estabished. Depth profiles served to determine the different influences of the formation and remineralisation of organic carbon and biogenic carbonate on the parameters total carbonate and alkalinity and to study the propagation of the anthropogenic CO_2 signal in the depths of Atlantic as calculated from these relationships. It was shown that organic acids in seawater do not interfere with analytic procedures for the potentiometric determination of total carbonate and alkalinity and that the consistent differences found between this and other methods do not occur if the electrode calibration factors are accurately taken into account. (orig.)Im Rahmen des Projektes 'Die Steuerfunktion des Karbonatsystems fuer die CO_2-Aufnahme durch den Ozean' wurden von Juni 1990 bis Februar 1993 sechs Expeditionen in den Atlantischen Ozean durchgefuehrt, auf denen die Parameter des Karbonatsystems, CO_2-Partialdruck, Gesamtkarbonatkonzentration und Alkalinitaet sowie Begleitparameter, wie Salzgehalt, Temperatur, Naehrsalze, Chlorophyll-Konzentrationen, gemessen wurden. Hiermit gelang es, ein Bild von der Partialdruckverteilung im Oberflaechenwasser des Atlantiks, der treibenden Kraft fuer den CO_2-Austausch mit der Atmosphaere, sowie deren raeumlicher und zeitlicher Variabilitaet zu erstellen und die relative Bedeutung der verschiedenen Einflussfaktoren aufzuzeigen. Anhand von Tiefenprofilen konnte der unterschiedliche Einfluss der Bildung und Remineralisierung von organischem Kohlenstoff und biogenem Karbonat auf die Parameter Gesamtkarbonat und Alkalinitaet dargestellt und die Ausbreitung des aus diesen Zusammenhaengen berechneten anthropogenen CO_2-Signals im Tiefenwasser des Atlantiks verfolgt werden. Es konnte gezeigt werden, dass das analytische Verfahren zur potentiometrischen Bestimmung von Gesamtkarbonat und Alkalinitaet nicht durch organische Saeuren im Meerwasser gestoert wird, sondern dass die beobachteten systematischen Differenzen zu anderen Methoden bei exakter Beruecksichtigung der Elektrodeneichfaktoren nicht auftreten. (orig.)SIGLEAvailable from TIB Hannover: F94B0206 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman
A uniform, quality controlled Surface Ocean CO2 Atlas (SOCAT)
A well documented, publicly available, global data set of surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC), were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968–2007). Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities
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