Articulate brachiopods of the Llandovery rocks of the Severn River, Ekwan River and Attawapiskat formations of the Hudson Bay Lowlands comprise 35 genera and 50 species, including 18 new species: Severella pinnigera, Gypidula rudiplicativa, Rhytidorhachis guttuliformis, Rostricellula subtilicostata, Microsphaeridiorhynchus hercostomaticum, Hercotrema spissicostatum, Meifodia discoidalis, Atyrypoidea praelingulata, Atrypopsis severnensis, Parmula hemisphaerica, Merista rhombiformis, Whitfieldella pygmaea, Whitfieldella sulcatina, Howellella porcata, Alaskospira fabiformis, Dalejina striata, Eoplectodonta (Eoplectodonta) hudsonensis, and Protochonetes harricanensis. The species of Alaskospira, Atrypoidea and Merista represent unusually early appearances of these genera. The biohermal complexes of the Attawapiskat Formation provided a great diversity of environments. Some species with small shells seem to have occupied specialized and protected niches within the complexes, whereas large, thick shelled species occupied open water environments. Three brachiopod assemblage zones can be recognized. The Virgiana decussata Zone (dominantly pentamerids) is succeeded by the Hercotrema winiskensisþStegerhynchus borealis Zone (dominantly rhynchonellids). Above, the Pentameroides septentrionalisþLissatrypa variabilis Zone has a very varied fauna with abundant pentamerids and spire-bearers. Species diversity increases from 6, to 15, and to 36 species in the three zones. The changes in diversity and in taxonomic composition were probably related to the changes in environments during the Early Silurian transgression from dominantly intertidal and lagoonal to dominantly subtidal and reefal. Correlations with successions on Anticosti and Manitoulin islands indicate that the Severn River Formation is latest Rhuddanian to late Aeronian in age, the Ekwan River Formation is Telychian, and the Attawpiskat Formation is late Telychian. Comparison with the outcrop succession of southern Manitoba indicates correlation of the basal Severn River Formation with the Fisher Branch Formation; the remainder of the Severn River Formation with the Moose Lake or ``Inwood'' (sensu McCabe), Atikameg, and East Arm formations; and the Ekwan River and the Attawapiskat Formation with the Cedar Lake Formation, but with the uppermost Attawapiskat being slightly younger.

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Brachiopods of the Upper Ordovician (Maysvillian- Richmondian) rocks of the Portage Chute, Surprise Creek, Caution Creek, and Chasm Creek formations and the undivided Bad Cache Rapids and Churchill River groups of the Hudson Bay Lowlands comprise 15 genera and 27 species of orthids, strophomenids, rhynchonellids, and atrypids, including one new species, Tetraphalerella churchillensis, an unusually large and flat strophomenid. Strophomenids are the dominant group, rhynchonellids and orthids are relatively common, and atrypids occur in small numbers at a few localities. Pentamerid and athyrid brachiopods have not been found, and inarticulate brachiopods are known only in the Kaskattama Province No. 1 Well. Two brachiopod assemblage zones are recognized, which correspond approximately to the Bad Cache Rapids and Churchill River groups, respectively. The lower Tetraphalerella churchillensis-Kjaerina hartae Zone contains 13 species, which indicate a Maysvillian age for the uppermost Portage Chute and Surprise Creek formations. The basal Portage Chute Formation has sparse fossils and cannot be dated precisely. The boundary between the lower zone and the Dinorthis occidentalis- Hiscobeccus capax Zone is defined by the appearance of 11 species in the lower Caution Creek Formation. Twenty-one species in the upper zone indicate a Richmondian age for the Caution Creek and Chasm Creek formations. In composition, the brachiopod faunas of the Hudson Bay region are most closely related to those from the Upper Ordovician rocks of southern Manitoba. Many species in the T. churchillensis-K. hartae Zone are also present in the Selkirk Member of the Red River Formation, and those in the D. occidentalis-H. capax Zone are characteristic of the Gunn and Penitentiary members of the Stony Mountain Formation. Although represented largely by fragmentary specimens, the T. churchillensis-K. hartae Zone can be recognized between depths of 873.8 and 746.6 m in the Kaskattama Province No. 1 Well, extending into the Churchill River Group. Elements of the D. occidentalis-H. capax Zone are present at depths of 732.3 to 733.2 m, but the upper Churchill River Group and the Red Head Rapids Formation of the well have not yielded enough diagnostic brachiopods to allow the stratigraphic limits of the zone to be determined. Lithological and fossil evidence indicates that distribution of the brachiopod faunas in the Hudson Bay Basin was not as strongly controlled by sea-level fluctuations as it was in the northeastern Williston Basin (southern Manitoba). Some brachiopod and coral species show continuous ranges from the Bad Cache Rapids Group to the Churchill River Group, which does not support the concept of a major hiatus between the groups, as advocated by several previous studies. The two brachiopod assemblages are characterized by large shell sizes and high diversity of species, which indicate a normal, open, shallow- and warm-water, subtidal depositional environment for the Bad Cache Rapids and Churchill River sediments during Late Ordovician time.

 The second version of Chinese Academy of Sciences Earth System Model (CAS-ESM2) is described.  Strength and weakness of the model simulations from the CMIP6 DECK experiments are described along possible causes.  The model has an equilibrium climate sensitivity of 3.4 K with a positive cloud feedback from the shortwave radiation.

The performances of CMIP5 atmospheric general circulation models (AGCMs) in simulating the western North Pacific subtropical high (WNPSH) in El Niño decaying summers are examined in this study. Results show that most models can reproduce the spatial pattern of both climatological and anomalous circulation associated with the WNPSH in El Niño decaying summers. Most CMIP5 AGCMs can capture the westward shift of the WNPSH in El Niño decaying summers compared with the climatological location. With respect to the sub-seasonal variation of the WNPSH, the performances of these AGCMs in reproducing the northward jump of the WNPSH are better than simulating the eastward retreat of the WNPSH from July to August. Twenty-one out of twenty-two (20 out of 22) models can reasonably reproduce the northward jump of the WNPSH in El Niño decaying summers (climatology), while only 7 out of 22 (8 out of 22) AGCMs can reasonably reproduce the eastward retreat of the WNPSH in El Niño decaying summers (climatology). In addition, there is a close connection between the climatological WNPSH location bias and that in El Niño decaying summers. 摘要

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An archaeological site at Anshan in the coastal area of Fujian province, southern China, was excavated in 2007, 2009 and 2015. Abundant artefacts including adzes, cores, bronze fishhook, pottery and bone arrowheads are found in the aeolian sediments. The aim of this article is to understand the geomorphological backdrop and process of Anshan site, and the coupling relationship between human activity and environmental evolution. In this study, optically stimulated luminescence (OSL) technique was employed to establish the chronological framework of the site. Samples from the top and bottom of cultural layer yield OSL ages ranging from 1.4 to 6.1 ka, providing a systematic geochronological evidence for the development of ‘Anshan culture’ in coastal area of southern Fujian province and eastern Guangdong province. In the meantime, there is a clear link between the varying regional sea levels, the chronology of regional wind-sand deposition and the period of Anshan culture since the mid-Holocene.