La correspondance transatlantique des Prize Papers (1744-1763) : famille, commerce et communications en temps de guerre

Au cours des années comprises entre 1744 et 1763, le monde atlantique connaît deux guerres majeures. La France et ses colonies américaines sont impliquées dans une lutte acharnée contre l’Empire britannique. Les deux puissances rivales misent alors largement sur la guerre de course. Au-delà des conséquences commerciales et militaires évidentes, la guerre de course perturba aussi les communications transatlantiques. En effet, la prise d’un navire signifiait le plus souvent la perte des lettres qu’il transportait ou, dans le meilleur des cas, leur saisie, interrompant du même coup l’acheminement maritime du courrier. Les archives des Prize Papers, conservant des lettres et autres documents saisis par des corsaires britanniques, incarnent bien cette réalité. On y trouve notamment de nombreuses lettres françaises interceptées dans ces circonstances. Considérant que l’intérêt historique de ce fonds d’archives mérite d’être davantage souligné, cette recherche analysera donc certaines de ces correspondances françaises trouvées au sein des Prize Papers. À travers celles-ci, nous tenterons de reconstituer le système de communication transatlantique français et de ses acteurs en temps de guerre. Nous nous pencherons d’abord sur l’histoire de la constitution de ce fonds d’archives bien particulier, avant de présenter les pratiques de communication employées par les correspondants transatlantiques et les façons dont la guerre a pu les affecter. Il sera ensuite question des informations elles-mêmes qui furent véhiculées dans ce contexte si difficile.

Spooked: Britain, empire and intelligence since 1945

A collection of pieces on British intelligence including sources (Christopher R. Moran), methodology (Richard Aldrich), media (Philip H.J. Davies), historiography (Calder Walton and Christopher Andrew), South Africa and the Wilson government (Philip Murphy), Pakistan and ISI (Rob Johnson), and UK security policy in the face of radical Islam (Anthony Glees).

Statistical uncertainty of changes in winter storms over the North Atlantic and Europe in an ensemble of transient climate simulations

Winter storms are among the most important natural hazards affecting Europe. We quantify changes in storm frequency and intensity over the North Atlantic and Europe under future climate scenarios in terms of return periods (RPs) considering uncertainties due to both sampling and methodology. RPs of North Atlantic storms' minimum central pressure (CP) and maximum vorticity (VOR) remain unchanged by 2100 for both the A1B and A2 scenarios compared to the present climate. Whereas shortened RPs for VOR of all intensities are detected for the area between British Isles/North-Sea/western Europe as early as 2040. However, the changes in storm VOR RP may be unrealistically large: a present day 50 (20) year event becomes approximately a 9 (5.5) year event in both A1B and A2 scenarios by 2100. The detected shortened RPs of storms implies a higher risk of occurrence of damaging wind events over Europe.

Factors contributing to the development of extreme North Atlantic cyclones and their relationship with the NAO

The occurrence of extreme cyclones is analysed in terms of their relationship to the NAO phase and the dominating environmental variables controlling their intensification. These are latent energy (equivalent potential temperature 850 hPa is used as an indicator), upper-air baroclinicity, horizontal divergence and jet stream strength. Cyclones over the North Atlantic are identified and tracked using a numerical algorithm, permitting a detailed analysis of their life cycles. Extreme cyclones are selected as the 10% most severe in terms of intensity. Investigations focus on the main strengthening phase of each cyclone. The environmental factors are related to the NAO, which affects the location and orientation of the cyclone tracks, thus explaining why extreme cyclones occur more (less) frequently during strong positive (negative) NAO phases. The enhanced number of extreme cyclones in positive NAO phases can be explained by the larger area with suitable growth conditions, which is better aligned with the cyclone tracks and is associated with increased cyclone life time and intensity. Moreover, strong intensification of cyclones is frequently linked to the occurrence of extreme values of growth factors in the immediate vicinity of the cyclone centre. Similar results are found for ECHAM5/OM1 for present day conditions, demonstrating that relationships between the environment factors and cyclones are also valid in the GCM. For future climate conditions (following the SRES A1B scenario), the results are similar, but a small increase of the frequency of extreme values is detected near the cyclone cores. On the other hand, total cyclone numbers decrease by 10% over the North Atlantic. An exception is the region near the British Isles, which features increased track density and intensity of extreme cyclones irrespective of the NAO phase. These changes are associated with an intensified jet stream close to Europe. Moreover, an enhanced frequency of explosive developments over the British Isles is found, leading to more frequent windstorms affecting Europe.

Size at maturity of Atlantoraja platana (Gunther, 1880) (Chondrichthyes : Rajidae : Arhynchobatinae) in the south-west Atlantic Ocean

The sexual development of Atlantoraja platana from the south-west Atlantic Ocean was analysed. According to the reproductive variables considered for both sexes, males were found to mature at 620 mm and females at 715 mm total length. (c) 2008 The Authors Journal compilation (c) 2008 The Fisheries Society of the British Isles.

The goatfish Pseudupeneus maculatus and its follower fishes at an oceanic island in the tropical west Atlantic

The influence of a substratum-disturbing forager, the spotted goatfish Pseudupeneus maculatus on the assemblage of its escorting, opportunistic-feeding fishes was examined at Fernando de Noronha Archipelago (tropical west Atlantic). Followers attracted to spotted goatfish foraging singly differed from followers of spotted goatfish foraging in groups in several characteristics. The larger the nuclear fish group, the greater the species richness and number of individuals of followers. Moreover, groups of foraging spotted goatfish attracted herbivores, not recorded for spotted goatfish foraging singly. The size of follower individuals increased with the size and the number of foraging spotted goatfish. The zoobenthivorous habits of the spotted goatfish and its ability to disturb a variety of soft substrata render it an important nuclear fish for several follower species of the reef fish assemblage at Fernando de Noronha. (c) 2006 the Authors Journal compilation (c) 2006 the Fisheries Society of the British Isles.

Reproductive biology of an endemic Physalaemus of the Brazilian Atlantic forest, and the trade-off between clutch and egg size in terrestrial breeders of the P. signifer group

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reproductive biology of the guitarfish Rhinobatos percellens (Chondrichthyes, Rhinobatidae) from the São Paulo Coast, Brazil, western South Atlantic Ocean

The reproductive biology of the guitarfish Rhinobatos percellens was studied from 751 specimens caught by bottom pair trawlers off the coast of São Paulo, Brazil, between c. 24° 00′ S; 45° 15′ W and c. 25° 10′ S; 47° 52′ W, from September 2007 to August 2009. The total length (LT) and total mass (MT) relationship for males and females combined was MT = 1·29E-06 LT 3·15 (r = 0·99, n = 751). The mean LT of sexually mature specimens was 548 mm for males and 583 mm for females. Clasper growth was allometric and showed three distinct phases. Most claspers were calcified in specimens of c. 550 mm LT. The mean diameter of the largest oocyte was 29·8 mm, the mean ovarian fecundity was seven oocytes and ovulation occurred between August and November. Uterine fecundity ranged from two to 13 embryos (mean of five embryos). Larger females had higher litter sizes and larger embryos; the size-at-birth was c. 200 mm LT. The hepato-somatic index oscillated seasonally for males and females; the gonado-somatic index had little variation in males, but varied seasonally in females. The presence of many non-pregnant adult females and of encapsulated eggs during two consecutive seasons suggests a resting period between gestations and the possibility of diapause. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Is rainfall seasonality important for reproductive strategies in viviparous Neotropical pit vipers? A case study with Bothrops leucurus from the Brazilian Atlantic Forest

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Five new records of Luvarus imperialis (Acanthuroidei: Luvaridae) in the south-west Atlantic Ocean

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Phylogeny and phylogeography of the family Hyalidae (Crustacea: Amphipoda) along the northeast Atlantic coasts

The family Hyalidae comprises more than one hundred species, distributed worldwide. They are common and abundant in the littoral and shallow sublittoral habitats and they play an important role in the coastal food chain. Most studies about this family were dealing with taxonomy and ecology, while very little is known about phylogenetic relationship among genera and species. In the present study we aim to achieve the first approach of the phylogenetic patterns of this family in NE Atlantic Ocean and Mediterranean Sea, and to perform the first insight into the phylogeography Apohyale prevostii along both the North Atlantic coasts. In order to do that, eight species belonging to the genera Apohyale, Hyale, Serejohyale and Protohyale were investigated using the mitochondrial COI-5P barcode region. Specimens were collected along European and Moroccan Atlantic rocky shores, including Iceland, the British Isles, Macaronesia and in the Mediterranean Sea. Sequences of A. prevostii, from the NW Atlantic Ocean, available in BOLD and GenBank, were retrieved. As expected, phylogenetic analyses showed highly-divergent clades, clearly discriminating among different species clusters, confirming their morphology-based identifications. Although, within A. perieri, A. media, A. stebbingi, P. (Protohyale) schmidtii and S. spinidactylus, high genetic diversity was found, revealing putative cryptic species. The clade of A. prevostii and A. stebbingi appears well supported and divided from the other two congeneric species, and P. (Protohyale) schmidtii shows a basal divergence. The north-western Atlantic coasts were recently colonized by A. prevostii after the last glacial maximum from the European populations showing also a common haplotype in every population analysed. The use of the COI-5P as DNA barcode provided a good tool to underline the necessity of a revision of this emblematic family, as well as to discern taxonomically the possible new species flagged with this molecular device.

Strontium and Neodymium isotope composition of sediments from the North Atlantic

Sr and Nd isotopic compositions have been measured on the lithic fraction of last climatic cycle sediments from the North Atlantic (~40°N/~60°N), in order to identify the origins of the particles. From the reconstruction of their transport pathways, we deduce the mechanisms that explain their distributions. The main source regions are the Canadian shield (mostly the area of Baffin Bay and western Greenland), the Scandinavian shield, the European region (British Isles and Bay of Biscay), and Iceland. We observe a significant glacial/interglacial contrast, characterized by a dominant Icelandic input via near-bottom transport by North Atlantic Deep Water (NADW) during the interglacials and a largely continent-derived contribution of surface-transported, ice-rafted detritus (IRD) during the glacial period. During the last glacial period, the Heinrich events (abrupt, massive discharges of IRD) originated not only from the Laurentide ice sheet as heretofore envisioned but also from other sources. Three other major North Atlantic ice sheets (Fennoscandian, British Isles, and Icelandic) probably surged simultaneously, discharging ice and IRD into the North Atlantic. As opposed to theories implying a unique, Laurentide origin [Gwiazda et al., 1996 doi:10.1029/95PA03135] driven by an internal mechanism [MacAyeal, 1993 doi:10.1029/93PA02200], we confirm that the Icelandic and the Fennoscandian ice sheets also surged as recently proposed by other authors, and we here also distinguish a possible detrital contribution from the British Isles ice sheet. This pan-North Atlantic phenomenon thus requires a common regional, external forcing.

Diversity of planktonic foraminifer fauna found in 18 deep-sea cores from the North Atlantic

Greenland stadial/interstadial cycles are known to affect the North Atlantic's hydrography and overturning circulation and to cause ecological changes on land (e.g., vegetation). Hardly any information, directly expressed as diversity indices, however, exists on the impacts of these millennial-scale variations on the marine flora and fauna. We calculated three diversity indices (species richness, Shannon diversity index, Hurlbert's probability of interspecific encounter) for the planktonic foraminifer fauna found in 18 deep-sea cores covering a time span back to 60 ka. Clear differences in diversity response to the abrupt climate change can be observed and some records can be grouped accordingly. Core SO82-05 from the southern section of the subpolar gyre, the cores along the British margin and core MD04-2845 in the Bay of Biscay show two modes of diversity distribution, with reduced diversity (uneven fauna) during cold phases and the reverse (even fauna) during warm phases. Along the Iberian margin high species diversity prevailed throughout most of the glacial period. The exceptions were the Heinrich stadials when the fauna abruptly shifted from an even to an uneven or less even fauna. Diversity changes were often abrupt, but revealed a high resilience of the planktonic foraminifer faunas. The subtropical gyre waters seem to buffer the climatic effects of the Heinrich events and Greenland Stadials allowing for a quick recovery of the fauna after such an event. The current work clearly shows that planktonic foraminifer faunas quickly adapt to climate change, albeit with a reduced diversity.