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1.
《The Cartographic journal》2013,50(3):282-293
Cartographic projects of national importance are often only reported on in local journals which are published in the language of the author or mapping organisation. Owing to this, important maps and map series often stay unknown outside their country of origin. A case in point is the important Carte d’Afrique on a scale of 1∶2?000?000 which, during the last decades of the nineteenth century, was compiled by the French army officer Captain Richard de Régnauld de Lannoy de Bissy. The map made an enormous contribution to the history of cartography of Africa with regard to not only the discovery and exploration of the continent, but also the expansion of colonial control and the political rivalry between European powers. It was an impressive project to be executed by one man and at the time guaranteed a prominent position for the author in geographic and cartographic circles worldwide. Although afterwards superceded by many more accurate maps, Lannoy de Bissy’s map to date remains a lasting witness to the mapping of the ‘dark continent’ and of the fragile, hesitating progress made during the search for geographical knowledge before the advent of aerial photography and satellite imagery. 相似文献
2.
Christoph Förste Roland Schmidt Richard Stubenvoll Frank Flechtner Ulrich Meyer Rolf König Hans Neumayer Richard Biancale Jean-Michel Lemoine Sean Bruinsma Sylvain Loyer Franz Barthelmes Saskia Esselborn 《Journal of Geodesy》2008,82(6):331-346
The recent improvements in the Gravity Recovery And Climate Experiment (GRACE) tracking data processing at GeoForschungsZentrum
Potsdam (GFZ) and Groupe de Recherche de Géodésie Spatiale (GRGS) Toulouse, the availability of newer surface gravity data
sets in the Arctic, Antarctica and North-America, and the availability of a new mean sea surface height model from altimetry
processing at GFZ gave rise to the generation of two new global gravity field models. The first, EIGEN-GL04S1, a satellite-only
model complete to degree and order 150 in terms of spherical harmonics, was derived by combination of the latest GFZ Potsdam
GRACE-only (EIGEN-GRACE04S) and GRGS Toulouse GRACE/LAGEOS (EIGEN-GL04S) mean field solutions. The second, EIGEN-GL04S1 was
combined with surface gravity data from altimetry over the oceans and gravimetry over the continents to derive a new high-resolution
global gravity field model called EIGEN-GL04C. This model is complete to degree and order 360 and thus resolves geoid and
gravity anomalies at half- wavelengths of 55 km at the equator. A degree-dependent combination method has been applied in
order to preserve the high accuracy from the GRACE satellite data in the lower frequency band of the geopotential and to form
a smooth transition to the high-frequency information coming from the surface data. Compared to pre-CHAMP global high-resolution
models, the accuracy was improved at a spatial resolution of 200 km (half-wavelength) by one order of magnitude to 3 cm in
terms of geoid heights. The accuracy of this model (i.e. the commission error) at its full spatial resolution is estimated
to be 15 cm. The model shows a reduced artificial meridional striping and an increased correlation of EIGEN-GL04C-derived
geostrophic meridional currents with World Ocean Atlas 2001 (WOA01) data. These improvements have led to select EIGEN-GL04C
for JASON-1 satellite altimeter data reprocessing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献