A Case for Geographic Masses

Geographic masses, the stuff we deal with that cannot be categorized as geographic objects, comprise a crucial but largely unrecognized component of the core ontology of geographic information. Although masses have been rarely acknowledged in GIScience, they appear in geographic discourse just as often as objects. A concise but consistent formal definition of a geographic mass particular, which distinguishes a mass from an object, can be applied to any endurant phenomena, enabling a richer understanding of the geographic milieu, and more informed decision making during modeling and analysis processes

Anthropogenic and forest fire pollution aerosol transported to the Arctic: observations from the POLARCAT-France spring campaign

During the POLARCAT-France airborne measurement campaign in spring 2008, several pollution plumes transported from mid-latitude regions were encountered. The study presented here focuses on air masses from two different geographic origins (Europe and Asia) and from 2 different source types (anthropogenic pollution and forest fires). One case study analyses an European air mass, which was sampled during three consecutive day. Modelling of the aerosol particle ageing by coagulation suggests that coagulation cannot solely explain the evolution of the size distributions, which is particularly true for the accumulation mode. Analyses of the aerosol refractory size distributions indicate that the Aitken mode was mostly composed of volatile compounds, while accumulation mode particles desorbed to a refractory mode yielding a modal mean diameter evolving from 48 to 59 nm for the three consecutive days of sampling the same air mass. The single refractory mode suggests an internally mixed aerosol population which is supported from electron microscopy and subsequent EDX analyses of the accumulation mode particles. Another case study focuses on European air masses polluted by fire emissions and Asian air masses with contributions from both biomass burning and anthropogenic emissions. On the one hand, the aerosol size distributions of the European biomass burning plumes are almost mono-modal with most of the particles found in the aged accumulation mode which desorbed uniformly. On the other hand, Asian air masses were more complex because of the mixing of different source contributions related to more variable and multimodal ambient and refractory aerosol size distributions. Electron microscopy illustrated soot-like inclusions in several samples. Within samples attributed to forest fire sources, the chemical signature is highly associated with the presence of potassium, which is characteristic for biomass burning plumes. The particle images suggest an internal mixing of sampled aerosol particles

Unnamed locations, underspecified regions, and other linguistic phenomena in geographic annotation of water-based locations

This short paper investigates how locations in or close to water masses in topics and documents (e.g. rivers, seas, oceans) are referred to. For this study, 13 topics from the GeoCLEF topics 2005-2008 aiming at documents on rivers, oceans, or sea names were selected and the corresponding relevant documents retrieved and manually annotated. Results of the geographic annotation indicate that i) topics aiming at locations close to water contain a wide variety of spatial relations (indicated by dierent prepositions), ii) unnamed locations can be generated on-the-fly by referring to movable objects (e.g. ships, planes) travelling along a path, iii) underspecied regions are referenced by proximity or distance or directional relations. In addition, several generic expressions (e.g. "in international waters") are frequently used, but refer to different underspecified regions

Oceanographic drivers of deep-sea coral species distribution and community assembly on seamounts, islands, atolls, and reefs within the Phoenix Islands Protected Area

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Auscavitch, S. R., Deere, M. C., Keller, A. G., Rotjan, R. D., Shank, T. M., & Cordes, E. E. Oceanographic drivers of deep-sea coral species distribution and community assembly on seamounts, islands, atolls, and reefs within the Phoenix Islands Protected Area. Frontiers in Marine Science, 7, (2020): 42, doi:10.3389/fmars.2020.00042.The Phoenix Islands Protected Area, in the central Pacific waters of the Republic of Kiribati, is a model for large marine protected area (MPA) development and maintenance, but baseline records of the protected biodiversity in its largest environment, the deep sea (>200 m), have not yet been determined. In general, the equatorial central Pacific lacks biogeographic perspective on deep-sea benthic communities compared to more well-studied regions of the North and South Pacific Ocean. In 2017, explorations by the NOAA ship Okeanos Explorer and R/V Falkor were among the first to document the diversity and distribution of deep-water benthic megafauna on numerous seamounts, islands, shallow coral reef banks, and atolls in the region. Here, we present baseline deep-sea coral species distribution and community assembly patterns within the Scleractinia, Octocorallia, Antipatharia, and Zoantharia with respect to different seafloor features and abiotic environmental variables across bathyal depths (200–2500 m). Remotely operated vehicle (ROV) transects were performed on 17 features throughout the Phoenix Islands and Tokelau Ridge Seamounts resulting in the observation of 12,828 deep-water corals and 167 identifiable morphospecies. Anthozoan assemblages were largely octocoral-dominated consisting of 78% of all observations with seamounts having a greater number of observed morphospecies compared to other feature types. Overlying water masses were observed to have significant effects on community assembly across bathyal depths. Revised species inventories further suggest that the protected area it is an area of biogeographic overlap for Pacific deep-water corals, containing species observed across bathyal provinces in the North Pacific, Southwest Pacific, and Western Pacific. These results underscore significant geographic and environmental complexity associated with deep-sea coral communities that remain in under-characterized in the equatorial central Pacific, but also highlight the additional efforts that need to be brought forth to effectively establish baseline ecological metrics in data deficient bathyal provinces.Funding for this work was provided by NOAA Office of Ocean Exploration and Research (Grant No. NA17OAR0110083) to RR, EC, TS, and David Gruber

Phylogenetic Analysis of Algal Symbionts Associated with Four North American Amphibian Egg Masses

Egg masses of the yellow-spotted salamander Ambystoma maculatum form an association with the green alga “Oophila amblystomatis” (Lambert ex Wille), which, in addition to growing within individual egg capsules, has recently been reported to invade embryonic tissues and cells. The binomial O. amblystomatis refers to the algae that occur in A. maculatum egg capsules, but it is unknown whether this population of symbionts constitutes one or several different algal taxa. Moreover, it is unknown whether egg masses across the geographic range of A. maculatum, or other amphibians, associate with one or multiple algal taxa. To address these questions, we conducted a phylogeographic study of algae sampled from egg capsules of A. maculatum, its allopatric congener A. gracile, and two frogs: Lithobates sylvatica and L. aurora. All of these North American amphibians form associations with algae in their egg capsules. We sampled algae from egg capsules of these four amphibians from localities across North America, established representative algal cultures, and amplified and sequenced a region of 18S rDNA for phylogenetic analysis. Our combined analysis shows that symbiotic algae found in egg masses of four North American amphibians are closely related to each other, and form a well-supported clade that also contains three strains of free-living chlamydomonads. We designate this group as the ‘Oophila’ clade, within which the symbiotic algae are further divided into four distinct subclades. Phylogenies of the host amphibians and their algal symbionts are only partially congruent, suggesting that host-switching and co-speciation both play roles in their associations. We also established conditions for isolating and rearing algal symbionts from amphibian egg capsules, which should facilitate further study of these egg mass specialist algae

Gas-Rich Companions of Isolated Galaxies

We have used the VLA to search for gaseous remnants of the galaxy formation process around six extremely isolated galaxies. We found two distinct HI clouds around each of two galaxies in our sample (UGC 9762 & UGC 11124). These clouds are rotating and appear to have optical counterparts, strongly implying that they are typical dwarf galaxies. The companions are currently weakly interacting with the primary galaxy, but have short dynamical friction timescales (~1 Gyr) suggesting that these triple galaxy systems will shortly collapse into one massive galaxy. Given that the companions are consistent with being in circular rotation about the primary galaxy, and that they have small relative masses, the resulting merger will be a minor one. The companions do, however, contain enough gas that the merger will represent a significant infusion of fuel to drive future star formation, bar formation, or central activity, while building up the mass of the disk thus making these systems important pieces of the galaxy formation and evolution process.Comment: Corrected dynamical friction calculation error. Revised discussion & conclusions. 7 pages, 4 tables, 6 figures, to appear in May 1999 Astronomical Journa

Mapping for the Masses: Accessing Web 2.0 through Crowdsourcing

The authors describe how we are harnessing the power of web 2.0 technologies to create new approaches to collecting, mapping, and sharing geocoded data. The authors begin with GMapCreator that lets users fashion new maps using Google Maps as a base. The authors then describe MapTube that enables users to archive maps and demonstrate how it can be used in a variety of contexts to share map information, to put existing maps into a form that can be shared, and to create new maps from the bottom-up using a combination of crowdcasting, crowdsourcing, and traditional broadcasting. The authors conclude by arguing that such tools are helping to define a neogeography that is essentially "mapping for the masses,'' while noting that there are many issues of quality, accuracy, copyright, and trust that will influence the impact of these tools on map-based communication

Aerosol chemical composition in Asian continental outflow during the TRACE-P campaign: Comparison with PEM-West B

Aerosol associated soluble ions and the radionuclide tracers 7Be and 210Pb were quantified in 414 filter samples collected in spring 2001 from the DC-8 during the Transport and Chemical Evolution over the Pacific (TRACE-P) campaign. Binning the data into near Asia (flights from Hong Kong and Japan) and remote Pacific (all other flights) revealed large enhancements of NO3−, SO4=, C2O4=, NH4+, K+, Mg2+, and Ca2+ near Asia. The boundary layer and lower troposphere were most strongly influenced by continental outflow, and the largest enhancements were seen in Ca2+ (a dust tracer) and NO3− (reflecting uptake of HNO3 onto the dust). Comparing the TRACE P near Asia bin with earlier results from the same region during PEM-West B (in 1994) shows at least twofold enhancements during TRACE P in most of the ions listed above. Calcium and NO3− were most enhanced in this comparison as well (more than sevenfold higher in the boundary layer and threefold higher in the lower troposphere). Independent estimation of Asian emissions of gaseous precursors of the aerosol-associated ions suggest only small changes between the two missions, and precipitation fields do not suggest any significant difference in the efficiency of the primary sink, precipitation scavenging. It thus appears that with the possible exception of dust, the enhancements of aerosol-associated species during TRACE P cannot be explained by stronger sources or weaker sinks. We argue that the enhancements largely reflect the fact that TRACE P focused on characterizing Asian outflow, and thus the DC-8 was more frequently flown into regions that were influenced by well-organized flow off the continent