scholarly journals Late Sandbian (Sa2) radiolarians of the Pingliang Formation from the Guanzhuang section, Gansu Province, China

2021 ◽  
pp. 1-27
Author(s):  
Siyumini Perera ◽  
Jonathan C. Aitchison
Keyword(s):  
New Genus ◽  
Gansu Province ◽  
Sea Surface ◽  
Micro Computed Tomography ◽  
Ecological Stress ◽  
Radiolarian Assemblage ◽  
Global Cooling ◽  
Family Level ◽  
Tropical Sea ◽  
Porous Spheres

Abstract A diverse, well-preserved radiolarian assemblage is reported from the Sandbian age Climacograptus bicornis Graptolite Biozone. This new assemblage, recovered from the Pingliang Formation in the Guanzhuang section, China, includes six new species along with 13 other previously described taxa. Geminusphaera new genus incorporates G. grandis n. sp. and G. kongtongensis n. sp. and is proposed for inaniguttids constructed from two distinct porous spheres bearing seven or more primary spines. Protopylentonema new genus is introduced to incorporate pylomate entactinarians with five-rayed initial spicules. It includes P. ordosensis n. sp. as well as P. aperta, P. rimata, and P. insueta that were formerly assigned to Kalimnasphaera. Micro-computed tomography investigation of skeletal microstructure supports establishment of the new genera together with other new spumellarian species: Haplotaeniatum implexa n. sp., Inanigutta quadrispinosa n. sp., and Kalimnasphaera pingliangensis n. sp. It also indicates that family-level reassignment of Etymalbaillella from the Proventocitidae to the Ceratoikiscidae is appropriate. Global distribution of Late Ordovician radiolarian occurrences highlights a strong preference for areas with equatorial to tropical sea surface temperatures. This must have led to ecological stress among radiolarian communities in adapting to global cooling in the Hirnantian. UUID: http://zoobank.org/3d3f55b8-0e70-4f9f-9738-265750d8ec3a.

scholarly journals The HadGEM2 family of Met Office Unified Model climate configurations

2011 ◽  
Vol 4 (3) ◽  
pp. 723-757 ◽  
Author(s):  
◽  
N. Bellouin ◽  
W. J. Collins ◽  
I. D. Culverwell ◽  
P. R. Halloran ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Specific Model ◽  
Unified Model ◽  
Sea Surface ◽  
Climate Feedbacks ◽  
Vertical Extension ◽  
Overall Performance ◽  
Tropical Sea ◽  
Different Levels ◽  
Model Family

Abstract. We describe the HadGEM2 family of climate configurations of the Met Office Unified Model, MetUM. The concept of a model "family" comprises a range of specific model configurations incorporating different levels of complexity but with a common physical framework. The HadGEM2 family of configurations includes atmosphere and ocean components, with and without a vertical extension to include a well-resolved stratosphere, and an Earth-System (ES) component which includes dynamic vegetation, ocean biology and atmospheric chemistry. The HadGEM2 physical model includes improvements designed to address specific systematic errors encountered in the previous climate configuration, HadGEM1, namely Northern Hemisphere continental temperature biases and tropical sea surface temperature biases and poor variability. Targeting these biases was crucial in order that the ES configuration could represent important biogeochemical climate feedbacks. Detailed descriptions and evaluations of particular HadGEM2 family members are included in a number of other publications, and the discussion here is limited to a summary of the overall performance using a set of model metrics which compare the way in which the various configurations simulate present-day climate and its variability.

scholarly journals Relationships between tropical sea surface temperature and top-of-atmosphere radiation

2010 ◽  
Vol 37 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Kevin E. Trenberth ◽  
John T. Fasullo ◽  
Chris O'Dell ◽  
Takmeng Wong
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Sea Surface ◽  
Tropical Sea

scholarly journals Five new species and one new genus of recent miliolid foraminifera from Raja Ampat (West Papua, Indonesia)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2157
Author(s):  
Meena Förderer ◽  
Martin R. Langer
Keyword(s):  
New Species ◽  
Benthic Foraminifera ◽  
Large Scale ◽  
New Genus ◽  
Marine Biodiversity ◽  
Sample Material ◽  
Micro Computed Tomography ◽  
Computed Tomography Images ◽  
Nearshore Environments ◽  
West Papua

Raja Ampat is an archipelago of about 1,500 small islands located northwest off the Bird’s Head Peninsula of Indonesia’s West Papua province. It is part of the Coral Triangle, a region recognized as the “epicenter” of tropical marine biodiversity. In the course of a large-scale survey on shallow benthic foraminifera we have discovered one new genus and five new species of recent miliolid benthic foraminifera from the highly diverse reefal and nearshore environments. The new fischerinid genusDentoplanispirinellais characterized by its planispiral coiling and by the presence of a simple tooth, that differentiate it fromPlanispirinellaWiesner. It is represented in our sample material by the new speciesDentoplanispirinella occulta. The other four species described herein areMiliolinella moia, Miliolinella undina, Triloculina kaweaandSiphonaperta hallocki.All new species are comparatively rare and occur sporadically in the sample material. Detailed morphological descriptions, scanning electron microscopy pictures of complete and dissected specimens as well as micro-computed tomography images are provided.

scholarly journals An updated classification of the jumping plant-lice (Hemiptera: Psylloidea) integrating molecular and morphological evidence

2021 ◽  
Vol 736 ◽  
pp. 137-182
Author(s):  
Daniel Burckhardt ◽  
David Ouvrard ◽  
Diana M. Percy
Keyword(s):  
New Species ◽  
New Genus ◽  
Molecular Data ◽  
Data Sources ◽  
Morphological Evidence ◽  
Sampling Strategies ◽  
Molecular Studies ◽  
Family Level ◽  
A New Species

The classification of the superfamily Psylloidea is revised to incorporate findings from recent molecular studies, and to integrate a reassessment of monophyla primarily based on molecular data with morphological evidence and previous classifications. We incorporate a reinterpretation of relevant morphology in the light of the molecular findings and discuss conflicts with respect to different data sources and sampling strategies. Seven families are recognised of which four (Calophyidae, Carsidaridae, Mastigimatidae and Triozidae) are strongly supported, and three (Aphalaridae, Liviidae and Psyllidae) weakly or moderately supported. Although the revised classification is mostly similar to those recognised by recent authors, there are some notable differences, such as Diaphorina and Katacephala which are transferred from Liviidae to Psyllidae. Five new subfamilies and one new genus are described, and one secondary homonym is replaced by a new species name. A new or revised status is proposed for one family, four subfamilies, four tribes, seven subtribes and five genera. One tribe and eight genera / subgenera are synonymised, and 32 new and six revised species combinations are proposed. All recognised genera of Psylloidea (extant and fossil) are assigned to family level taxa, except for one which is considered a nomen dubium.

Tropical temperature in the Maastrichtian Danish Basin: Data from coccolith Δ47 and δ18O

Geology ◽  
2019 ◽  
Vol 47 (11) ◽  
pp. 1074-1078 ◽  
Author(s):  
Mattia Tagliavento ◽  
Cédric M. John ◽  
Lars Stemmerik
Keyword(s):  
Sea Surface ◽  
Polar Regions ◽  
Sea Surface Temperatures ◽  
Ice Caps ◽  
Greenhouse Climate ◽  
The North ◽  
Surface Temperatures ◽  
Higher Temperature ◽  
Clumped Isotope ◽  
Tropical Sea

Abstract The Cretaceous Earth, with its greenhouse climate and absence of major ice caps in the polar regions, represents an extreme scenario for modeling future warming. Despite considerable efforts, we are just at the verge of fully understanding the conditions of a warm Earth, and better, more extensive proxy evidence is needed to solve existing discrepancies between the applied temperature proxies. In particular, the Maastrichtian temperature trends are controversial, since data indicate cooling in the South Atlantic and contemporary warming of the North Atlantic. The “heat piracy” hypothesis involves northward heat transport to midlatitudes via oceanic currents and is used to explain the contrasting polar cooling/warming patterns. Here, we present Δ47 and δ18O data from nine coccolith-enriched samples from a shallow core taken from the Danish Basin (Chalk Sea), representing a key location at the northern mid-latitudes. Based on Δ47 data of coccolith-enriched material, sea-surface temperatures for the late Campanian–Maastrichtian ranged from 24 °C to 30 °C, with an average of 25.9 °C ± 2 °C. This is 4–6 °C higher than estimates based on Δ47 of bulk samples and 8–10 °C higher than reported temperatures based on bulk δ18O data from the same core. However, these higher temperature estimates are lower, but overall in line with estimates of Late Cretaceous tropical sea-surface temperatures from TEX86 (tetraether index of 86 carbons), when considering latitudinal differences. The study highlights the potential of clumped isotope paleothermometry on coccoliths as a valid, reliable proxy with which to reconstruct sea-surface temperatures.

scholarly journals Differential trends in tropical sea surface and atmospheric temperatures since 1979

2001 ◽  
Vol 28 (1) ◽  
pp. 183-186 ◽  
Author(s):  
John R. Christy ◽  
David E. Parker ◽  
Simon J. Brown ◽  
Ian Macadam ◽  
Martin Stendel ◽  
...  
Keyword(s):  
Sea Surface ◽  
Tropical Sea

scholarly journals Tropical sea-surface temperature reconstruction for the early Paleogene using Mg/Ca ratios of planktonic foraminifera

2003 ◽  
Vol 18 (4) ◽  
pp. n/a-n/a ◽  
Author(s):  
Aradhna K. Tripati ◽  
Margaret L. Delaney ◽  
James C. Zachos ◽  
Linda D. Anderson ◽  
Daniel C. Kelly ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Planktonic Foraminifera ◽  
Temperature Reconstruction ◽  
Sea Surface ◽  
Tropical Sea ◽  
Early Paleogene
Sign in / Sign up

Export Citation Format

Share Document