Solar Spicules: A Review of Recent Models and Targets for Future Observations – (Invited Review)     

Alphonse C. Sterling 《Solar physics》2000,196(1):79-111

Since their discovery over 100 years ago, there have been many suggestions for the origin and development of solar spicules. Because the velocities of spicules are comparable to the sound and Alfvén speeds of the low chromosphere, linear theory cannot fully describe them. Consequently, detailed tests of theoretical ideas had to await the development of computing power that only became available during the 1970s. This work reviews theories for spicules and spicule-like features over approximately the past 25 years, with an emphasis on the models based on nonlinear numerical simulations. These models have given us physical insight into wave propagation in the solar atmosphere, and have helped elucidate how such waves, and associated shock waves, may be capable of creating motions and structures on magnetic flux tubes in the lower solar atmosphere. So far, however, it has been difficult to reproduce the most-commonly-quoted parameters for spicules with these models, using what appears to be the most suitable input parameters. A key impediment to developing satisfactory models has been the lack of reliable observational information, which is a consequence of the small angular size and transient lifetime of spicules. I close with a list of key observational questions to be addressed with space-based satellites, such as the currently operating TRACE satellite, and especially the upcoming Solar-B mission. Answers to these questions will help determine which, if any, of the current models correctly explains spicules.  相似文献   

Radiation balance over a salt marsh     

Sterling J. Crabtree Jr.  Björn Kjerfve 《Boundary-Layer Meteorology》1978,14(1):59-66

Linear relationships have been found between daytime incoming radiation and both net radiation and reflected radiation over a Spartina alterniflora salt marsh at North Inlet, S.C., during the summer. On the average, using total daytime values, net radiation was 70 ± 9% and reflected radiation was 9 ± 1% of incoming radiation.  相似文献   

A geovisual analytics exploration of the OpenStreetMap crowd     

Sterling D. Quinn  Alan M. MacEachren 《制图学和地理信息科学》2018,45(2):140-155

It is sometimes easy to forget that massive crowdsourced data products such as Wikipedia and OpenStreetMap (OSM) are the sum of individual human efforts stemming from a variety of personal and institutional interests. We present a geovisual analytics tool called Crowd Lens for OpenStreetMap designed to help professional users of OSM make sense of the characteristics of the “crowd” that constructed OSM in specific places. The tool uses small multiple maps to visualize each contributor’s piece of the crowdsourced whole, and links OSM features with the free-form commit messages supplied by their contributors. Crowd Lens allows sorting and filtering contributors by characteristics such as number of contributions, most common language used, and OSM attribute tags applied. We describe the development and evaluation of Crowd Lens, showing how a multiple-stage user-centered design process (including testing by geospatial technology professionals) helped shape the tool’s interface and capabilities. We also present a case study using Crowd Lens to examine cities in six continents. Our findings should assist institutions deliberating OSM’s fitness for use for different applications. Crowd Lens is also potentially informative for researchers studying Internet participation divides and ways that crowdsourced products can be better comprehended with visual analytics methods.  相似文献   

Potential for offsetting diamond mine carbon emissions through mineral carbonation of processed kimberlite: an assessment of De Beers mine sites in South Africa and Canada     

Mervine  Evelyn M.  Wilson  Sasha  Power  Ian M.  Dipple  Gregory M.  Turvey  Connor C.  Hamilton  Jessica L.  Vanderzee  Sterling  Raudsepp  Mati  Southam  Colette  Matter  Juerg M.  Kelemen  Peter B.  Stiefenhofer  Johann  Miya  Zandile  Southam  Gordon 《Mineralogy and Petrology》2018,112(2):755-765

De Beers kimberlite mine operations in South Africa (Venetia and Voorspoed) and Canada (Gahcho Kué, Victor, and Snap Lake) have the potential to sequester carbon dioxide (CO₂) through weathering of kimberlite mine tailings, which can store carbon in secondary carbonate minerals (mineral carbonation). Carbonation of ca. 4.7 to 24.0 wt% (average = 13.8 wt%) of annual processed kimberlite production could offset 100% of each mine site’s carbon dioxide equivalent (CO₂e) emissions. Minerals of particular interest for reactivity with atmospheric or waste CO₂ from energy production include serpentine minerals, olivine (forsterite), brucite, and smectite. The most abundant minerals, such as serpentine polymorphs, provide the bulk of the carbonation potential. However, the detection of minor amounts of highly reactive brucite in tailings from Victor, as well as the likely presence of brucite at Venetia, Gahcho Kué, and Snap Lake, is also important for the mineral carbonation potential of the mine sites.

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