Seasonal variation of aliphatic amines in marine sub-micrometer particles at the Cape Verde islands

Monomethylamine (MA), dimethylamine (DMA) and diethylamine (DEA) were detected at non-negligible concentrations in sub-micrometer particles at the Cap Verde Atmospheric Observatory (CVAO) located on the island of São Vicente in Cape Verde during algal blooms in 2007. The concentrations of these amines in five stage impactor samples ranged from 0–30 pg m−3 for MA, 130–360 pg m−3 for DMA and 5–110 pg m−3 for DEA during the spring bloom in May 2007 and 2–520 pg m−3 for MA, 100–1400 pg m−3 for DMA and 90–760 pg m−3 for DEA during an unexpected winter algal bloom in December 2007. Anomalously high Saharan dust deposition and intensive ocean layer deepening were found at the Atmospheric Observatory and the associated Ocean Observatory during algal bloom periods. The highest amine concentrations in fine particles (impactor stage 2, 0.14–0.42 μm) indicate that amines are likely taken up from the gas phase into the acidic sub-micrometer particles. The contribution of amines to the organic carbon (OC) content ranged from 0.2–2.5% C in the winter months, indicating the importance of this class of compounds to the carbon cycle in the marine environment. Furthermore, aliphatic amines originating from marine biological sources likely contribute significantly to the nitrogen content in the marine atmosphere. The average contribution of the amines to the detected nitrogen species in sub-micrometer particles can be non-negligible, especially in the winter months (0.1% N–1.5% N in the sum of nitrate, ammonium and amines). This indicates that these smaller aliphatic amines can be important for the carbon and the nitrogen cycles in the remote marine environment

AtlantOS Deliverable 3.8: OceanSITES Networking Report

During the course of AtlantOS, our ability to provide biogeochemical (BGC) time series and Eulerian data which is of sufficient quality and quantity to approach basin-scale capacity has improved in a major way in some areas but has declined or not progressed in others. Indeed, the increased coordination achieved through AtlantOS has both increased our capacity to collectively further a basin-scale operation, and revealed new challenges in implementation. These outcomes are synthesised in this report to improve future planning for Eulerian capacities in BGC observation. Areas of significant progress 1. Development of capacity for emerging BGC variables 2. Establishment of a system for developing “Best practice” recording. 3. Transatlantic MOU with Canada 4. Data management and dissemination The ways to address the areas in which progress has not been made are conceptually simple but practically demanding. In all cases this needs to be carried out at the global scale and therefore under the auspices of OceanSITES. A coherent system which can provide data of sufficient quality and quantity to address societal needs cannot be achieved in isolation by any one Nation state or by Europe and must not be restricted by discipline. It will become self-evident that such an integrated approach will lead to a system which performs at a much higher level than the sum of its component parts. With continuous pressure from the European Commission, further and additional support from member states, continuing political and scientific dialogue with South Atlantic countries and strong management encouragement at all levels, the establishment of an effective eulerian observatory network is anticipated within the coming decade

Rapid cooling and increased storminess triggered by freshwater in the North Atlantic

Recent winters have been unique due to the rapid and extreme cooling of the subpolar North Atlantic. Here, we present a novel view on its causes and consequences. Combining in‐situ observations with remote sensing and atmospheric reanalysis data, we show that increased freshening of the subpolar region gives rise to a faster surface cooling in fall and winter. Large freshwater events, in particular, result in pronounced cold anomalies with sharp temperature gradients that promote an enhanced storminess. The storms reinforce the cooling by driving stronger heat losses and modulating the surface flow. Consistent with this mechanism, past freshwater events have been followed by cold anomalies in winter of ~‐2°C and increases in the North Atlantic Oscillation index of up to~0.6 within 3 years. We expect that future freshwater discharges into the North Atlantic will amplify the cold anomaly and trigger an enhanced wintertime storminess with far‐reaching climatic implications

Test Results on the Silicon Pixel Detector for the TTF-FEL Beam Trajectory Monitor

Test measurements on the silicon pixel detector for the beam trajectory monitor at the free electron laser of the TESLA test facility are presented. To determine the electronic noise of detector and read-out and to calibrate the signal amplitude of different pixels the 6 keV photons of the manganese K line are used. Two different methods determine the spatial accuracy of the detector: In one setup a laser beam is focused to a straight line and moved across the pixel structure. In the other the detector is scanned using a low-intensity electron beam of an electron microscope. Both methods show that the symmetry axis of the detector defines a straight line within 0.4 microns. The sensitivity of the detector to low energy X-rays is measured using a vacuum ultraviolet beam at the synchrotron light source HASYLAB. Additionally, the electron microscope is used to study the radiation hardness of the detector.Comment: 14 pages (Latex), 13 figures (Postscript), submitted to Nuclear Instruments and Methods

Potential for an underwater glider component as part of the Global Ocean Observing System

The contributions of autonomous underwater gliders as an observing platform in the in-situ global ocean observing system (GOOS) are investigated. The assessment is done in two ways: First, the existing in-situ observing platforms contributing to GOOS (floats, surface drifters, moorings, research/commercial ships) are characterized in terms of their current capabilities in sampling key physical and bio-geochemical oceanic processes. Next the gliders’ capabilities are evaluated in the context of key applications. This includes an evaluation of 140 references presented in the peer-reviewed literature. It is found that GOOS has adequate coverage of sampling in the open ocean for several physical processes. There is a lack of data in the present GOOS in the transition regions between the open ocean and shelf seas. However, most of the documented scientific glider applications operate in this region, suggesting that a sustained glider component in the GOOS could fill that gap. Glider data are included for routine product generation (e.g. alerts, maps). Other noteworthy process-oriented applications where gliders are important survey tools include local sampling of the (sub)mesoscale, sampling in shallow coastal areas, measurements in hazardous environments, and operational monitoring. In most cases, the glider studies address investigations and monitoring of processes across multiple disciplines, making use of the ease to implement a wide range of sensors to gliders. The maturity of glider operations, the wide range of applications that map onto growing GOOS regional needs, and the maturity of glider data flow all justify the formal implementation of gliders into the GOOS. Remaining challenges include the execution of coordinated multinational missions in a sustained mode as well as considering capacity-building aspects in glider operations as well as glider data use

Mean circulation and EKE distribution in the Labrador Sea Water level of the subpolar North Atlantic

A long-term mean flow field for the subpolar North Atlantic region with a horizontal resolution of approximately 25&thinsp;km is created by gridding Argo-derived velocity vectors using two different topography-following interpolation schemes. The 10-day float displacements in the typical drift depths of 1000 to 1500&thinsp;m represent the flow in the Labrador Sea Water density range. Both mapping algorithms separate the flow field into potential vorticity (PV) conserving, i.e., topography-following contribution and a deviating part, which we define as the eddy contribution. To verify the significance of the separation, we compare the mean flow and the eddy kinetic energy (EKE), derived from both mapping algorithms, with those obtained from multiyear mooring observations.The PV-conserving mean flow is characterized by stable boundary currents along all major topographic features including shelf breaks and basin-interior topographic ridges such as the Reykjanes Ridge or the Rockall Plateau. Mid-basin northward advection pathways from the northeastern Labrador Sea into the Irminger Sea and from the Mid-Atlantic Ridge region into the Iceland Basin are well-resolved. An eastward flow is present across the southern boundary of the subpolar gyre near 52°&thinsp;N, the latitude of the Charlie Gibbs Fracture Zone (CGFZ).The mid-depth EKE field resembles most of the satellite-derived surface EKE field. However, noticeable differences exist along the northward advection pathways in the Irminger Sea and the Iceland Basin, where the deep EKE exceeds the surface EKE field. Further, the ratio between mean flow and the square root of the EKE, the Peclet number, reveals distinct advection-dominated regions as well as basin-interior regimes in which mixing is prevailing.</p

Fast and reasonable Installation, Experience and Acceptance of a Remote Control Room

Remote control systems are becoming more and more important to give us the flexibility to control facilities, provide assistance and intervene in case of problems at any time and from every place. As a global operating group CALICE [2] with approx. 220 members worldwide is dependent on using a remote control system for shifts and monitoring of the data taking. CALICE has at present installed its detector at Fermilab, Chicago, where will run test beam experiments for the next year. The components of the remote control system and kind of use are presented here.Comment: 4 page

OceanSITES Networking Report

Report and linked workshop on the European and Transatlantic plan for sustaining ocean observation by biogeochemical Eulerian Observatorie