The High-Resolution Coronal Imager (Hi-C)

The High-Resolution Coronal Imager (Hi-C) was flown on a NASA sounding rocket on 11 July 2012. The goal of the Hi-C mission was to obtain high-resolution (≈?0.3?–?0.4′′), high-cadence (≈?5 seconds) images of a solar active region to investigate the dynamics of solar coronal structures at small spatial scales. The instrument consists of a normal-incidence telescope with the optics coated with multilayers to reflect a narrow wavelength range around 19.3 nm (including the Fe xii 19.5-nm spectral line) and a 4096×4096 camera with a plate scale of 0.1′′?pixel^?1. The target of the Hi-C rocket flight was Active Region 11520. Hi-C obtained 37 full-frame images and 86 partial-frame images during the rocket flight. Analysis of the Hi-C data indicates the corona is structured on scales smaller than currently resolved by existing satellite missions.     

The effect of sideband ratio on line intensity for Herschel/HIFI

The Heterodyne Instrument for the Far Infrared (HIFI) on board the Herschel Space Observatory is composed of a set of fourteen double sideband mixers. We discuss the general problem of the sideband ratio (SBR) determination and the impact of an imbalanced sideband ratio on the line calibration in double sideband heterodyne receivers. The HIFI SBR is determined from a combination of data taken during pre-launch gas cell tests and in-flight. The results and some of the calibration artefacts discovered in the gas cell test data are presented here along with some examples of how these effects appear in science data taken in orbit.     

Observations of shocked [FeII] and H2 line profiles in orion bullet wakes

Recent near-IR imaging of the Orion molecular cloud has revealed a complex of dense bullets, visible as [FeII] emitting HH-objects at the tips of H₂ wakes, ejected explosively from the cloud core. Having resolved individual bow-shock structures for the first time in this bright source, we have observed [FeII] 1.644µm velocity profiles of selected bullets and H₂ 1-0 S(1), 2.122µm velocity profiles for a series of positions along and across the corresponding bow-shock wakes. We present observed profiles for the bullet M42 HH1 and its associated wake and compare with theoretical bow-shock models.     

Understanding high-magnitude outburst floods

High-magnitude outburst floods are 'catastrophic' geological agents, transforming landscapes through erosion and deposition within a matter of hours. Landform records of high-magnitude outburst floods can be preserved which can help us reconstruct their hydraulic properties. It is important to understand these properties, as high-magnitude floods not only drastically alter landscapes over very short time-scales, but also provide sudden and abrupt inputs of water and sediment to oceans. They pose a world-wide hazard to people, livestock, property and infrastructure. In this article we examine methods by which it is possible to reconstruct, and gain a better understanding of, high-magnitude flood processes and mechanisms.     

Testing solar forcing of pervasive Holocene climate cycles

The temporal and spatial extent of Holocene climate change is an area of considerable uncertainty, with solar forcing recently proposed to be the origin of cycles identified in the North Atlantic region. To address these issues we have developed an annually resolved record of changes in Irish bog tree populations over the last 7468 years which, together with radiocarbon‐dated bog and lake‐edge populations, extend the dataset back to ～9000 yr ago. The Irish trees underpin the internationally accepted radiocarbon calibration curve, used to derive a proxy of solar activity, and allow us to test solar forcing of Holocene climate change. Tree populations and age structures provide unambiguous evidence of major shifts in Holocene surface moisture, with a dominant cyclicity of 800 yr, similar to marine cycles in the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. The cycles, however, are not coherent with changes in solar activity (both being on the same absolute timescale), indicating that Holocene North Atlantic climate variability at the millennial and centennial scale is not driven by a linear response to changes in solar activity. Copyright © 2005 John Wiley & Sons, Ltd.     

The inception of novae transition zone oscillations

The nature of semi-regular oscillations in the transition zones of certain novae is discussed. It is found that hydrostatic collapse following a reduction of radiative support for the photospheric layers is a likely explanation of transition zone inception.     

CLINICALLY APPLIED MEDICAL GEOGRAPHY: ITS ROLE IN TRAVEL MEDICINE

Medical geography frequently contributes to public health, but rarely are medical geographic concepts applied in clinical settings. This article describes the application of medical geographic concepts to an academic travel and tropical medicine clinical service at University Hospital in Seattle, and reviews the role of a medical geographer in this particular clinical setting. Applied concepts of medical geography improve the quality of patient care for overseas travellers and recent immigrants to the United States.     

The structure of Neptune's upper atmosphere: The stellar occultation of 24 May 1981

Observations of the 24 May 1981 occultation of an uncatalogued star by Neptune made at the Cerro Tololo Inter-American Observatory have been analyzed to yield temperature profiles of Neptune's upper atmosphere for number densities near 5 × 10¹³ cm^?3. The mean temperatures at immersion (latitude ?56°) and emersion (latitude ?16°) obtained by numerical inversion were 140 ± 10°K and 154 ± 10°K, respectively. The immersion and emersion profiles are remarkably similar in overall shape, suggestive of global atmospheric layering. From the astrometry of the event, precise relative positions of Neptune and the occulted were obtained.     

Us public and private regulation of LNG transport

The authors examine the propositions that the private banking sector is capable of assuring that liquefied natural gas (LNG) projects are economically viable and that the insurance sector is capable of rating the relative risks of LNG projects to assure their operations are as safe as possible. If the markets could assure these outcomes, government regulation of LNG projects could be reduced. Reviews of public and private regulation of safety and economic viability suggest that the private sector cannot serve these functions adequately. Unless private financial and insurance enterprises are induced by government regulations to smooth their own operating cycles, private self-regulation of major new developments is unlikely to be effective. In the case of LNG, the red tape of governmental bureaucracy may have prevented the large-scale development of costly, potentially hazardous, white elephants, but for all the wrong reasons.