Recent Developments in the Law of the Sea: Synopsis

As part of its annual symposium on the law of the sea, the San Diego Law Review compiles a summary of significant recent developments in the field. This seventh annual synopsis reports major events which occurred between January 1, 1975, and December 31, 1975. Scope, format, and approach are substantially as employed in the past; a minor change is the extended use of footnotes, including citations to newspapers

The impact of the 1783-1784 AD Laki eruption on global aerosol formation processes and cloud condensation nuclei

The 1783–1784 AD Laki flood lava eruption commenced on 8 June 1783 and released 122 Tg of sulphur dioxide gas over the course of 8 months into the upper troposphere and lower stratosphere above Iceland. Previous studies have examined the impact of the Laki eruption on sulphate aerosol and climate using general circulation models. Here, we study the impact on aerosol microphysical processes, including the nucleation of new particles and their growth to cloud condensation nuclei (CCN) using a comprehensive Global Model of Aerosol Processes (GLOMAP). Total particle concentrations in the free troposphere increase by a factor ~16 over large parts of the Northern Hemisphere in the 3 months following the onset of the eruption. Particle concentrations in the boundary layer increase by a factor 2 to 5 in regions as far away as North America, the Middle East and Asia due to long-range transport of nucleated particles. CCN concentrations (at 0.22% supersaturation) increase by a factor 65 in the upper troposphere with maximum changes in 3-month zonal mean concentrations of ~1400 cm<sup>−3</sup> at high northern latitudes. 3-month zonal mean CCN concentrations in the boundary layer at the latitude of the eruption increase by up to a factor 26, and averaged over the Northern Hemisphere, the eruption caused a factor 4 increase in CCN concentrations at low-level cloud altitude. The simulations show that the Laki eruption would have completely dominated as a source of CCN in the pre-industrial atmosphere. The model also suggests an impact of the eruption in the Southern Hemisphere, where CCN concentrations are increased by up to a factor 1.4 at 20° S. Our model simulations suggest that the impact of an equivalent wintertime eruption on upper tropospheric CCN concentrations is only about one-third of that of a summertime eruption. The simulations show that the microphysical processes leading to the growth of particles to CCN sizes are fundamentally different after an eruption when compared to the unperturbed atmosphere, underlining the importance of using a fully coupled microphysics model when studying long-lasting, high-latitude eruptions

Divergence in Dialogue

Copyright: 2014 Healey et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This work was supported by the Economic and Social Research Council (ESRC; http://www.esrc.ac.uk/) through the DynDial project (Dynamics of Conversational Dialogue, RES-062-23-0962) and the Engineering and Physical Sciences Research Council (EPSRC; http://www.epsrc.ac.uk/) through the RISER project (Robust Incremental Semantic Resources for Dialogue, EP/J010383/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Sustainable biomass production in agroforestry systems

Non-Peer ReviewedResearch conducted in 2007 through 2009 on the occasional biomass harvest from willow rings could provide balanced co-existence between agriculture and wetlands. This would provide biomass feedstock while preserving the wetland for future generations. The focus of the research will be on the sustainable production of biomass in agroforestry systems. The goals of this research project are to determine the impact of biomass harvest on re-growth of willow rings; evaluate the feasibility of mechanical harvest using a bio-baler; determine the biomass yield and production costs; and quantify fuel characteristics of harvested willow. Results have shown that the bio-baler tested can efficiently harvest biomass from willow rings at a rate of 6.5 tonnes/hour. The re-growth of the willows was rapid and was not impacted by the harvest. There are thousands of hectares of wetlands and surrounding willow rings available on the Canadian landscape for harvesting at a reasonable cost of production. The willow ring biomass harvested is suitable for small scale heating systems. Additional research will be conducted on the utilization of the biomass harvested from willow rings as a bioenergy source to supply a biomass boiler for heating purposes at the Agriculture and Agri-Food Canada (AAFC) Agroforestry Development Centre (ADC) in Indian Head, Saskatchewan. This research will include the economics and environmental aspects and will consider the life cycle analysis

Radial HI Profiles at the Periphery of Galactic Disks: The Role of Ionizing Background Radiation

Observations of neutral hydrogen in spiral galaxies reveal a sharp cutoff in the radial density profile at some distance from the center. Using 22 galaxies with known HI distributions as an example, we discuss the question of whether this effect can be associated exclusively with external ionizing radiation, as is commonly assumed. We show that before the surface density reaches $\sigma_{\textrm{HI}}\le 0.5 {\cal M}_\odot/{\textrm {pc}}^2$(the same for galaxies of different types), it is hard to expect the gas to be fully ionized by background radiation. For two of 13 galaxies with a sharp drop in the HI profile, the "steepening" can actually be caused by ionization. At the same time, for the remaining galaxies, the observed cutoff in the radial HI profile is closer to the center than if it was a consequence of ionization by background radiation and, therefore, it should be caused by other factors.Comment: 15 pages, 6 figure

Franz Volhard lecture: should doctors still measure blood pressure? The missing patients with masked hypertension

The traditional reliance on blood pressure (BP) measurement in the medical setting misses a significant number of individuals with masked hypertension, who have normal clinic BP but persistently high daytime BP when measured out of the office. We suggest that masked hypertension may be a precursor of clinically recognized sustained hypertension and is associated with increased cardiovascular risk compared with consistent normotension. We discuss factors that may contribute to clinic–daytime BP differences as well as the changing relationship between these two measures over time. Anxiety at the time of BP measurement and having been diagnosed as hypertensive appear to be two possible mechanisms. The identification of individuals with masked hypertension is of great clinical importance and requires out-of-office BP screening. Ambulatory BP monitoring is the best established technique for doing this, but home monitoring may be applicable in the future

Spitzer Observations of Low Luminosity Isolated and Low Surface Brightness Galaxies

We examine the infrared properties of five low surface brightness galaxies (LSBGs) and compare them with related but higher surface brightness galaxies, using Spitzer Space Telescope images and spectra. All the LSBGs are detected in the 3.6 and 4.5um bands, representing the stellar population. All but one are detected at 5.8 and 8.0um, revealing emission from hot dust and aromatic molecules, though many are faint or point-like at these wavelengths. Detections of LSBGs at the far-infrared wavelengths, 24, 70, and 160um, are varied in morphology and brightness, with only two detections at 160um, resulting in highly varied spectral energy distributions. Consistent with previous expectations for these galaxies, we find that detectable dust components exist for only some LSBGs, with the strength of dust emission dependent on the existence of bright star forming regions. However, the far-infrared emission may be relatively weak compared with normal star-forming galaxies.Comment: 20 pages, 8 figures, accepted to Ap

Automatic Methods of Gas Analysis Depending upon Thermal Conductivity

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