India & South Asia, 1752 (Image 2 of 2) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Carte de l'Inde : dressée pour la Compagnie des Indes, par le Sr. d'Anville, Sécrétaire de S.A.S. Mgr. le Duc d'Orleans ; [engraved by] Guill.' de-la-Haye. It was published by Jean Baptiste Bourguignon d'Anville in November 1752. Scale [ca. 1:3,100,000]. This layer is image 2 of 2 total images of the two sheet source map, representing the southern portion of the map. Covers India and portions of South Asia. Map in French. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Kalianpur 1975 India Zone III projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, roads, shoreline features, and more. Relief shown pictorially. Includes insets: Negraïs -- Rivière d'Aracan -- Riv. de Sirian -- Archipel de Merghi -- Environs de Junk Selon -- Environs d'Ashem -- Entréé du Gange -- Environs de Goa. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Central America & Caribbean Region, 1803 (Image 1 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Chart of the West Indies and Spanish Dominions in North America, by A. Arrowsmith ; Jones, Smith & Co., sc. Beaufort Buildgs., Strand. It was published June 1st, 1803, by A. Arrowsmith, No. 24 Rathbone Place. Scale [ca. 1:2,775,525]. This layer is image 1 of 4 total images of the four sheet source map, representing the northeast portion of the map. Covers primarily Central America and the Caribbean region.The image inside the map neatline is georeferenced to the surface of the earth and fit to the World Miller Cylindrical projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, shoreline features, roads, mines, and more. Relief shown by hachures, depths shown by soundings. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Central America & Caribbean Region, 1803 (Image 2 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Chart of the West Indies and Spanish Dominions in North America, by A. Arrowsmith ; Jones, Smith & Co., sc. Beaufort Buildgs., Strand. It was published June 1st, 1803, by A. Arrowsmith, No. 24 Rathbone Place in 1803. Scale [ca. 1:2,775,525]. This layer is image 2 of 4 total images of the four sheet source map, representing the southeast portion fo the map. Covers primarily Central America and the Caribbean region.The image inside the map neatline is georeferenced to the surface of the earth and fit to the World Miller Cylindrical projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, shoreline features, roads, mines, and more. Relief shown by hachures, depths shown by soundings. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Central America & Caribbean Region, 1803 (Image 3 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Chart of the West Indies and Spanish Dominions in North America, by A. Arrowsmith ; Jones, Smith & Co., sc. Beaufort Buildgs., Strand. It was published June 1st, 1803, by A. Arrowsmith, No. 24 Rathbone Place. Scale [ca. 1:2,775,525]. This layer is image 3 of 4 total images of the four sheet source map, representing the southwest portion fo the map. Covers primarily Central America and the Caribbean region.The image inside the map neatline is georeferenced to the surface of the earth and fit to the World Miller Cylindrical projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, shoreline features, roads, mines, and more. Relief shown by hachures, depths shown by soundings. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Central America & Caribbean Region, 1803 (Image 4 of 4) (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Chart of the West Indies and Spanish Dominions in North America, by A. Arrowsmith ; Jones, Smith & Co., sc. Beaufort Buildgs., Strand. It was published June 1st, 1803, by A. Arrowsmith, No. 24 Rathbone Place. Scale [ca. 1:2,775,525]. This layer is image 4 of 4 total images of the four sheet source map, representing the northwest portion fo the map. Covers primarily Central America and the Caribbean region.The image inside the map neatline is georeferenced to the surface of the earth and fit to the World Miller Cylindrical projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, shoreline features, roads, mines, and more. Relief shown by hachures, depths shown by soundings. Includes notes.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Africa, 1834 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Carte détaillée (en deux feuilles), de l'Afrique et des îles qui en dependent (partie septentrionale), par A. Broué, Géographe du Roi, d'après les observations astronomiques, les découvertes et les hypothèses les plus récentes. Revue en 1834. It was published by Chez l'Auteur in 1828, i.e. 1834. Scale [ca. 1:16,250,000]. Covers Africa and a small portion of Europe and the Middle East. Map in French.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Sinusoidal projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, territorial boundaries, roads, mines, shoreline features, and more. Relief shown by hachures. Includes notes and insets: Extrémité Sud de l'Afrique, ou Colonie du Cap, Pays des Hottentots et Betjouanas; Archipel du Nord-Est de Madagascar; Abyssinie et Pays des Gallas, etc.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Uranium, Thorium and Protactinium isotopes of ODP Site 172-1063

Ocean circulation may have undergone reductions and reinvigorations in the past closely tied to regional climate changes. Measurements of 231Pa/230Th ratios in a sediment core from the Bermuda Rise have been interpreted as evidence that the Atlantic Meridional Overturning Circulation (AMOC) was weakened or completely eliminated during a period of catastrophic iceberg discharges (Heinrich-Event 1, H1). Here we present new data from the Bermuda Rise that show further 231Pa/230Th peaks during Heinrich-2 (H2) and Heinrich-3 (H3). Additionally, a tight correlation between diatom abundances (biogenic silica) and 231Pa/230Th is discovered in this core. Our results redirect the interpretation of 231Pa/230Th from the Bermuda Rise as a proxy for ocean circulation towards a proxy that reacts highly sensitive to changes of particle composition and water mass properties.

(Table 1) Age determination of western North Atlantic sediment cores

Foraminiferal abundance, 14C ventilation ages, and stable isotope ratios in cores from high deposition rate locations in the western subtropical North Atlantic are used to infer changes in ocean and climate during the Younger Dryas (YD) and Last Glacial Maximum (LGM). The d18O of the surface dwelling planktonic foram Globigerinoides ruber records the present-day decrease in surface temperature (SST) of ~4°C from Gulf Stream waters to the northeastern Bermuda Rise. If during the LGM the modern d18O/salinity relationship was maintained, this SST contrast was reduced to 2°C. With LGM to interglacial d18O changes of at least 2.2 per mil, SSTs in the western subtropical gyre may have been as much as 5°C colder. Above ~2.3 km, glacial d13C was higher than today, consistent with nutrient-depleted (younger) bottom waters, as identified previously. Below that, d13C decreased continually to -0.5 per mil, about equal to the lowest LGM d13C in the North Pacific Ocean. Seven pairs of benthic and planktonic foraminiferal 14C dates from cores >2.5 km deep differ by 1100 ± 340 years, with a maximum apparent ventilation age of ~1500 years at 4250 m and at ~4700 m. Apparent ventilation ages are presently unavailable for the LGM < 2.5 km because of problems with reworking on the continental slope when sea level was low. Because LGM d13C is about the same in the deep North Atlantic and the deep North Pacific, and because the oldest apparent ventilation ages in the LGM North Atlantic are the same as the North Pacific today, it is possible that the same water mass, probably of southern origin, flowed deep within each basin during the LGM. Very early in the YD, dated here at 11.25 ± 0.25 (n = 10) conventional 14C kyr BP (equal to 12.9 calendar kyr BP), apparent ventilation ages <2.3 km water depth were about the same as North Atlantic Deep Water today. Below ~2.3 km, four YD pairs average 1030 ± 400 years. The oldest apparent ventilation age for the YD is 1600 years at 4250 m. This strong contrast in ventilation, which indicates a front between water masses of very different origin, is similar to glacial profiles of nutrient-like proxies. This suggests that the LGM and YD modes of ocean circulation were the same.

Atlantic 231Pa/230Th and biogenic opal compilation of the Holocene and the LGM

The strength and geometry of the Atlantic meridional overturning circulation is tightly coupled to climate on glacial-interglacial and millennial timescales, but has proved difficult to reconstruct, particularly for the Last Glacial Maximum. Today, the return flow from the northern North Atlantic to lower latitudes associated with the Atlantic meridional overturning circulation reaches down to approximately 4,000 m. In contrast, during the Last Glacial Maximum this return flow is thought to have occurred primarily at shallower depths. Measurements of sedimentary 231Pa/230Th have been used to reconstruct the strength of circulation in the North Atlantic Ocean, but the effects of biogenic silica on 231Pa/230Th-based estimates remain controversial. Here we use measurements of 231Pa/230Th ratios and biogenic silica in Holocene-aged Atlantic sediments and simulations with a two-dimensional scavenging model to demonstrate that the geometry and strength of the Atlantic meridional overturning circulation are the primary controls of 231Pa/230Th ratios in modern Atlantic sediments. For the glacial maximum, a simulation of Atlantic overturning with a shallow, but vigorous circulation and bulk water transport at around 2,000 m depth best matched observed glacial Atlantic 231Pa/230Th values. We estimate that the transport of intermediate water during the Last Glacial Maximum was at least as strong as deep water transport today.

Botryocladia exquisita; Rhodymeniaceae

Botryocladia exquisita C.W.Schneid. & C.E.Lane

Reise in Ostafrika in den Jahren 1903-1905, mit Mitteln der Hermann und Elise geb. Heckmann Wentzel-Stiftung ausgeführt. Wissenschaftliche Ergebnisse.

Contributions in German, English, French or Italian.