The Italian CTBTO Cooperating National Facility (CNF): status of the art

<p>The Italian National Institute for Oceanography and Experimental Geophysics (<em>Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS</em>) in Trieste (Italy) is offering, in agreement with the Italian CTBTO National Authority, its Cludinico (CLUD) seismic station as a Cooperating National Facility (CNF) to the CTBTO. As outlined in Pesaresi and Horn (2015) the additional data from the Italian CNF improve the CTBTO location capabilities in the Europe/Middle East area of about 21%, which might be of interest given the actual situation in Iran that breached the nuclear Joint Comprehensive Plan of Action (JCPOA) (Reuters, 2019).</p><p>In this presentation, we will illustrate the technical details of the solutions adopted to incorporate the Italian CNF into the CTBTO International Monitoring System (IMS): evaluation of CTBTO certification readiness, CTBTO Standard Station Interface (SSI) hardware and software procurement, test and installation, UPS upgrade, implementation and test of CTBTO communication, security measures.</p><p><strong>Reference</strong>:</p><p>Pesaresi, D., and Horn, N.: Improving CTBTO monitoring capabilities: the Italian proposal for a CNF, CTBT Science and Technology 2015, Vienna, Austria, 22-26 June 2015, T4.1-P31, doi:10.13140/RG.2.1.2862.1927, 2015.</p><p>Reuters: "Iran further breaches nuclear deal, says it can exceed 20% enrichment", https://www.reuters.com/article/us-iran-nuclear-idUSKCN1VS05B, last access: 14 January 2020, 2019.</p>

Feasibility study of using a "travelling" CO₂ and CH₄ instrument to validate continuous in-situ measurement stations

In the course of the ICOS (Integrated Carbon Observation System)Demo Experiment a feasibility study on the usefulness of a Travelling Comparison Instrument (TCI) was conducted in order to evaluate continuous atmospheric CO2 and CH4 measurements at two European stations. The aim of the TCI is to independently measure ambient air in parallel to the standard station instrumentation, thus providing a comprehensive comparison that includes the sample intake system, the instrument itself as well as its calibration and data evaluation. Observed differences between the TCI and the Heidelberg gas chromatographic system, which acted as a reference for the TCI, were −0.02 ± 0.08 μmol mol−1 for CO2 and −0.3 ± 2.3 nmol mol−1 for CH4. Over a period of two weeks each, the continuous CO2 and CH4 measurements at two ICOS field stations, Cabauw and OPE, were compared to co-located TCI measurements. At Cabauw mean differences of 0.21 ± 0.06 μmol mol−1 for CO2 and 0.41 ± 0.50 nmol mol−1 for CH4 were found. For OPE the mean differences were 0.13 ± 0.07 μmol mol−1 for CO2 and 0.44 ± 0.36 nmol mol−1 for CH4. Potential causes of these observed differences are leakages or contaminations in the intake lines and/or there flushing pumps. At Cabauw station an additional error contribution originates from insufficient flushing of standard gases. Offsets arising from differences in the working standard calibrations or leakages/contaminations in the drying systems are too small to explain the observed differences. Finally a comprehensive quality management strategy for atmospheric monitoring networks is proposed.

A source of major error in the digital analysis of World Wide Standard station seismograms

abstract A critical requirement in the digitization of analogue seismograms is that the y axis of the digitizing device be parallel to the recorded direction of swing of the galvanometer. Small misalignment of the seismogram on the digitizing table can produce major errors in the results of Fourier analysis and other digital techniques. In the examples discussed, the direction of the galvanometer swing was not parallel to the recording drum axis (the nominal direction of swing). Fourier spectra and group velocities are presented for cases in which the seismogram is aligned with the x axis of the digitizer: (1) parallel to the trace; (2) normal to the drum axis; (3) correctly aligned, normal to the direction of galvanometer swing. If the alignment is incorrect, the errors in the results are significant at both short and long periods and lead to erroneous geophysical conclusions. The magnitude of the errors increases with both the degree of misalignment and the amplitude of the recorded signal.

Massive upward displacement in the deep ocean

For a third of a century many and varied studies on sea water have been concentrated upon a single accessible shallow-water station in the English Channel, EI, supplemented by more extensive excursions usually designed to test working hypotheses. This concentration of effort has been richly rewarded. In deep-water oceanography a similar approach is appropriate; a standard station, ‘Cavall’ has therefore been selected in the north-eastern Bay of Biscay in 4700 m of water at lat. 46° 30' N., long. 8° 00' W., nominal, a position worked by the Danish Research Vessel ‘Dana’ in 1922 and 1930. It is not only the nearest deep water position to Plymouth but it has best possible coverage by the Decca Navigator system. For our experimental programme it is essential that the station positions be maintained and repeated precisely. To achieve this a working Decca chartlet (Fig. 1) on a scale of 1:20,000 has been prepared for each station from a portion of the Admiralty Decca Lattice chart no. L 1104. On this a circle of radius one mile is inscribed. Throughout operations the ship is maintained within this circle by stopping work when necessary and steaming back on Decca co-ordinates towards the centre, or beyond to pre-compensate expected drift.

The Protein Requirement of Growing Foxes

Summary Two experiments were conducted with a total of 248 fox pups to determine the protein requirements of young foxes during two periods of growth, 50 to 161 and 162 to 259 days of age. Protein was fed at 17.4, 22.9, 28.8, 34.3 and 40.7% levels for all growth periods in 1944. In 1945 protein at 16.4, 19.1, 22.0, 24.5, 27.2, 33.2 and 38.4% levels was fed for the period from 50 to 161 days of age. From 162 to 259 days, a 14.1% level was added and the 24.5% level eliminated. Controls were given a standard Station diet containing 27.4% protein. Growth, balance and carcass analyses were made for each period of growth. The requirement of protein to promote maximum nitrogen storage in a fox pup between the ages of 50 and 161 days is above 40.7% in the dry diet, but 28% of protein produced as rapid growth as higher intakes. It is suggested that growing foxes between 50 to 161 days of age should be given a nutrient allowance of 25 to 34% protein in their diets on a dry basis. This amount of protein is not enough to promote maximum storage of nitrogen, but foxes fed at these levels were as large at pelting time and had fully as good pelts as those fed larger amounts of protein. Since the animals are raised for their pelts only, it is possible to underfeed protein during the early stages of growth without detrimental results, if it is more economical. Between the ages of 162 to 259 days of age fox pups should have a nutrient allowance of from 19 to 25% protein in their diets on a dry basis. Male fox pups grew more rapidly and were larger than female fox pups at pelting time and they tended to have a slightly higher requirement for protein than females during the early stages of growth.