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Boebel O.,Alfred Wegener Institute for Polar and Marine Research | Zitterbart D.P.,AWI
75th EAGE Conference and Exhibition Incorporating SPE EUROPEC 2013 | Year: 2013

Detecting whales at sea by visual observation for mitigation purposes is inherently difficult and personal intensive while restricted to daylight hours. These caveats are overcome by the system described herein, which employs a state-of-the-art thermographic infrared scanner in conjunction with a learning computer algorithm to automatically and reliably detect whale blows. The stand-alone system provides detection, verification and documentation of each ship-whale encounter, allowing a retrospective review of every mitigation decision taken aboard. The system has been developed over the course of 5 years and was thoroughly tested in polar waters during 7 expeditions to the Arctic and Antarctic, accumulating 5871 hours of operation. Of these, 3472 hours, were analyzed with various learning automatic detection algorithms, which discovered about 4500 whale blows in this data. Direct comparisons of auto-detections with concurrent whale sightings by visual observers (double blind setup) confirm a very high degree of detection reliability within 2-3 nautical miles from the ship in subpolar and polar environments. The system, when used as a an "assistant", allows a single marine mammal observer to efficiently monitor the ships entire surroundings and to take instantly and retrospectively verifiable decisions regarding the use of airguns, as all relevant data is automatically stored. Source

Golynsky A.V.,VNIIOkeangeologia | Ivanov S.V.,PMGE | Kazankov A.J.,PMGE | Jokat W.,AWI | And 2 more authors.
Tectonophysics | Year: 2013

Over the past decade, Australian, Norwegian and Russian marine surveys have collected integrated seismic, gravity and magnetic data in the southern Indian Ocean. The more than 350,000 line-km of new airborne and marine magnetic observations for the East Antarctic continental margin have been compiled into an improved definition of crustal magnetic anomaly patterns. This compilation provides important new constraints on the breakup processes and igneous activity related to the formation of the passive margin of East Antarctica. The eastern sector of the map from Bruce Rise in the west to the D'Urville Sea in the east is largely dominated by seafloor spreading magnetic anomalies. The 'Adélie Rift Block' of highly stretched and extensively faulted continental crust is associated with a smooth anomaly fabric. Abrupt magnetic anomaly changes along the oceanic-continent transition in the Cooperation Sea including the Enderby Basin Anomaly extend for more than 1680. km from the Kerguelen Plateau towards the Cosmonaut Sea. Three sectors of the East Antarctic continental margin exhibit pronounced disparities in the anomaly patterns that strongly suggest different modes of seafloor formation. Strong positive seafloor magnetic anomalies mark the southern margin of the Kerguelen Plateau, the Maud Rise and adjacent areas in the Riiser-Larsen Sea. The new compilation suggests that at least 300. km of the Enderby Basin and Shackleton Basin may be part of the Cretaceous Kerguelen Volcanic Province and possibly maps an abandoned 'fossil' spreading center in the central Enderby Basin. The majority of the published age models for the Enderby Basin and "Australian sector" of the East Antarctic margin are not in agreement with the structural grain of magnetic anomalies in the newly compiled map. © 2012 Elsevier B.V. Source

Greatbatch R.J.,Leibniz Institute of Marine Science | Gollan G.,Leibniz Institute of Marine Science | Jung T.,AWI | Kunz T.,Leibniz Institute of Marine Science
Quarterly Journal of the Royal Meteorological Society | Year: 2012

Influences from the Tropics, the stratosphere and the specification of observed sea surface temperature and sea-ice (SSTSI) on Northern Hemisphere winter mean circulation anomalies during the period 1960/61 to 2001/02 are studied using a relaxation technique applied to the ECMWF model. On interannual time-scales, the Tropics strongly influence the Pacific sector but also the North Atlantic sector, although weakly. The stratosphere is found to be influential on the North Atlantic Oscillation (NAO) on interannual time-scales but is less important over the Pacific sector. Adding the observed SSTSI to the tropical relaxation runs generally improves the model performance on interannual time-scales but degrades/enhances the model's ability to capture the 42-year trend over the Pacific/Atlantic sector. While relaxing the stratosphere to the reanalysis fails to capture the trend over the whole 42-year period, the stratosphere is shown to be influential on the upward trend of the NAO index from 1965 to 1995, but with reduced amplitude compared to previous studies. Influence from the Tropics is found to be important for the trend over both time periods and over both sectors although, across all experiments, we can account for only 30% of the amplitude of the hemispheric trend. © 2012 Royal Meteorological Society. Source

Baird G.M.,AWI
Journal / American Water Works Association | Year: 2011

Issues associated with aging water infrastructure continue to emerge in many areas of the water industry. One such area is the issuance of precautionary boil-water notices resulting from the increased number of water main breaks in urban locations. This area of concern deals with the growing challenge of quickly isolating and controlling the break. The safety information card for utilities is their emergency response manual, which contains standard operating procedures (SOPs) to address such water quality incidents. The manual needs to have sections on critical control points, responding to a main break and adverse water quality incidents, along with subsections on disasters and terrorism. A critical control point (CCP) is also an essential point in the system at which control can be applied by the water utility to prevent or eliminate drinking water health hazards or reduce them to an acceptable level. Source

« Kenworth receives $8.6M in grants for low-emission T680 Day Cab drayage truck projects in California; hybrids, CNG hybrid and fuel cell | Main | TU Graz team uses monocrystalline Si as Li-ion anode; integrated micro batteries for on-board sensors » A team from the University of Vaasa (Finland) and UPM-Kymmene Corporation has examined how the blends of fossil and renewable diesel produced from crude tall oil (CTO) affect the performance and exhaust emissions of the modern common-rail off-road diesel engine. The study, published in the journal Fuel, used four different fuel blends of low-sulfur fossil diesel fuel oil and CTO renewable fuel, UPM BioVerno (HB): HB10, HB20, HB50, and HB100. UPM BioVerno renewable diesel is produced from wood-based tall oil. (Earlier post.) The suitability of this Finnish CTO renewable fuel has earlier been studied particularly in light-duty and passenger car vehicles. In the present study, CTO renewable diesel was investigated in a turbo-charged, intercooled common-rail non-road diesel engine. Considering the total demand of engine fuels and current supply of renewable fuels, it is realistic to concentrate on the blends of fossil and renewable fuels. In the present study, the renewable fuel was, however, also studied in neat form. As the baseline fossil fuel, regular low-sulfur Finnish DF was used. Crude tall is a natural extract of wood, mainly from conifers. The renewable raw material comes from sustainably managed forests. Crude tall oil is gained as a result of the separation process of fibrous material from wood; it is a residue of pulp manufacturing. CTO is a mixture of 36–58% fatty acids, 10–42% of rosin acids and 10–38% sterols and neutral substances. However, its composition depends on tree species, time of the year, growing cycle and age of the tree, conditions of pulping, and the geographic location. CTO renewable diesel was produced via hydrotreatment in the UPM biorefinery in Lappeenranta. Engine experiments were conducted by the University of Vaasa (UV) at the Internal Combustion Engine (ICE) laboratory of the Technobothnia Research Centre in Vaasa, Finland. The study used an AGCO POWER 44 AWI turbocharged, intercooled, four-cylinder, common-rail diesel engine. The engine had been tuned for high NO and the use of an SCR catalyst. No exhaust gas after-treatment system was, however, adopted for the current study—engine-out raw emissions were recorded during all measurements. The team conducted performance and emission measurements according to the NRSC cycle of the ISO8178 standard. No engine or parameter modifications were made. Among the findings: CTO renewable diesel showed performance and emissions results similar to those observed with GTL or BTL and oil- or fat-derived HVO fuels. NO emissions were approximately constant—a slight discrepancy between the FT and HVO fuels that seemed to also show slight reductions in NO . The authors noted that the fuel injection system of their present experimental engine was not at all optimized for the CTO fuel and its blends. The cycle-averaged CO and HC emissions decreased when CTO renewable fuel content of the fuel blend increased. The main reasons were assumed to be the considerably lower content of aromatic compounds and the higher cetane number of the CTO renewable fuel. The cycle-weighed NO emissions remained almost constant independent of fuel. Due to the high-NO tuning, the exhaust smoke was very low, almost negligible for all fuels. No coherent trend was observed in exhaust particle size distributions except at idle, where the increase in the HB content resulted in a clear reduction of ultra-fine particle number emissions. The peak number of particulates, however, tended to occur at slightly lower particle size category when the share of renewable fuel increased.

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