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Author |
Ritsema J, Deuss A, van Heijst H J, Woodhouse J H, |
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Title |
S40RTS: a degree-40 shear-velocity model for the mantle from new Rayleigh wave dispersion, teleseismic traveltime and normal-mode splitting function measurements
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Type |
Journal Article |
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Year |
2011 |
Publication |
Geophysical Journal International |
Abbreviated Journal |
0956-540X |
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Volume |
184 |
Issue |
3 |
Pages |
1223-1236 |
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Keywords |
Composition of the mantle, Body waves, Surface waves and free oscillations, Seismic tomography, |
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Abstract  |
We have developed model S40RTS of shear-velocity variation in Earth's mantle using a new collection of Rayleigh wave phase velocity, teleseismic body-wave traveltime and normal-mode splitting function measurements. This data set is an order of magnitude larger than used for S20RTS and includes new data types. The data are related to shear-velocity perturbations from the (anisotropic) PREM model via kernel functions and ray paths that are computed using PREM. Contributions to phase delays and traveltimes from the heterogeneous crust are estimated using model CRUST2.0. We calculate crustal traveltimes from long-period synthetic waveforms rather than using ray theory. Shear-velocity perturbations are parametrized by spherical harmonics up to degree 40 and by 21 vertical spline functions for a total of 35 301 degrees of freedom. S40RTS is characterised by 8000 resolved unknowns. Since we compute the exact inverse, it is straightforward to determine models associated with fewer or more unknowns by adjusting the model damping. S40RTS shares many characteristics with S20RTS because it is based on the same data types and similar modelling procedures. However, S40RTS shows more clearly than S20RTS the abrupt change in the pattern of shear-velocity heterogeneity across the 660-km phase transition and it presents a more complex patern of shear-velocity heterogeneity in the lower mantle. Utilities to visualise S40RTS and software to analyse the resolution of S40RTS (or models for different damping parameters) are made available.
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Blackwell Publishing Ltd |
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1365-246X |
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yes |
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Serial |
3793 |
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Author |
Priestley, K.; Debayle, E. |
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Title |
Seismic evidence for a moderately thick lithosphere beneath the Siberian Platform |
Type |
Journal Article |
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Year |
2003 |
Publication |
Geophysical research letters |
Abbreviated Journal |
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Volume |
30 |
Issue |
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Pages |
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Keywords |
7207 Seismology: Core and mantle; 7218 Seismology: Lithosphere and upper mantle; 7255 Seismology: Surface waves and free oscillations |
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Abstract |
We have built a Sv-wavespeed tomographic model for the upper mantle beneath the Siberian platform and surrounding region derived from the analysis of more than 13,000 fundamental and higher mode regional waveforms. The dense path coverage and rich higher mode content of the data allow building an upper mantle image with an horizontal resolution of a few hundred kilometers extending to ?400 km depth. The high velocity, upper mantle lid or seismic lithosphere is ?200 km thick beneath most of the Siberian platform but may extend to ?250 km depth beneath small areas. A high velocity seismic lid also underlies a large region west of the Siberian platform. Our observation of a ?200 thick seismic lithosphere beneath the Siberian platform on the slow-moving Eurasian plate, similar to the thickness of the seismic lithosphere beneath Precambrian terrains on the fast-moving Australian plate, suggests that a moderately thick seismic lithosphere beneath Precambrian terrains may be more common than previously supposed. |
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133;906 |
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American Geophysical Union |
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0094-8276 |
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yes |
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Call Number |
IPEV @ Thierry.Lemaire @ |
Serial |
5630 |
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Author |
Lautredou A-C, Motomura H, Gallut C, Ozouf-Costaz C, Cruaud C, Lecointre G, Dettai A, |
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Title |
New nuclear markers and exploration of the relationships among Serraniformes (Acanthomorpha, Teleostei): the importance of working at multiple scales
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Type |
Journal Article |
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Year |
2013 |
Publication |
MOLECULAR PHYLOGENETICS AND EVOLUTION |
Abbreviated Journal |
Mol. Phylogenet. Evol. |
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Volume |
67 |
Issue |
1 |
Pages |
140-155 |
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Keywords |
Animals, Bayes Theorem, Biological Evolution, Cell Nucleus, Fishes, Genetic Markers, Likelihood Functions, Models, Genetic, Phylogeny, Sequence Analysis, DNA, |
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Abstract |
We explore the relationships within Serraniformes (Li et al., 2009) using a dense taxon sampling and seven nuclear markers. Six had already used been for teleost phylogeny (IRBP, MC1R, MLL4, Pkd1, Rhodopsin, and RNF213) at other scales, and one (MLL2) is new. The results corroborate the composition of Serraniformes described in previous publications (some Gasterosteiformes, Perciformes and Scorpaeniformes). Within the clade, Notothenioidei and Zoarcoidei are each monophyletic. Cottoidei was not monophyletic due to placement of the genus Ebinania (Psychrolutidae). Our independent data confirm the sister-group relationship of Percophidae and Notothenioidei as well as the division of Platycephaloidei in four different groups (Bembridae, Platycephalidae, Hoplichthyidae and Peristediidae with Triglidae). Within Cottoidei, Liparidae and Cyclopteridae formed a clade associated with Cottidae, the genus Cottunculus (Psychrolutidae), and Agonidae. Serranidae and Scorpaenidae are not monophyletic, with the Serranidae divided in two clades (Serraninae and Epinephelinae/Anthiinae) and Scorpaenidae including Caracanthidae and the genus Ebinania (Psychrolutidae). We discuss some morphological characters supporting clades within the Scorpaenidae. |
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1124 |
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1095-9513 |
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yes |
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Call Number |
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Serial |
4519 |
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Author |
Lautredou A-C, Motomura H, Gallut C, Ozouf-Costaz C, Cruaud C, Lecointre G, Dettai A, |
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Title |
New nuclear markers and exploration of the relationships among Serraniformes (Acanthomorpha, Teleostei): The importance of working at multiple scales
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Type |
Journal Article |
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Year |
2013 |
Publication |
Molecular Phylogenetics and Evolution |
Abbreviated Journal |
Mol. Phylogenet. Evol. |
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Volume |
67 |
Issue |
1 |
Pages |
140-155 |
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Keywords |
Serraniformes, Scorpaenidae, Nuclear genes, Phylogeny, Scorpaeniformes, Perciformes, |
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Abstract |
We explore the relationships within Serraniformes (Li et al., 2009) using a dense taxon sampling and seven nuclear markers. Six had already used been for teleost phylogeny (IRBP, MC1R, MLL4, Pkd1, Rhodopsin, and RNF213) at other scales, and one (MLL2) is new. The results corroborate the composition of Serraniformes described in previous publications (some Gasterosteiformes, Perciformes and Scorpaeniformes). Within the clade, Notothenioidei and Zoarcoidei are each monophyletic. Cottoidei was not monophyletic due to placement of the genus Ebinania (Psychrolutidae). Our independent data confirm the sister-group relationship of Percophidae and Notothenioidei as well as the division of Platycephaloidei in four different groups (Bembridae, Platycephalidae, Hoplichthyidae and Peristediidae with Triglidae). Within Cottoidei, Liparidae and Cyclopteridae formed a clade associated with Cottidae, the genus Cottunculus (Psychrolutidae), and Agonidae. Serranidae and Scorpaenidae are not monophyletic, with the Serranidae divided in two clades (Serraninae and Epinephelinae/Anthiinae) and Scorpaenidae including Caracanthidae and the genus Ebinania (Psychrolutidae). We discuss some morphological characters supporting clades within the Scorpaenidae. |
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1124 |
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ISSN |
1055-7903 |
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yes |
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4834 |
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Author |
Harding A M A, Kitaysky A S, Hamer K C, Hall M E, Welcker J, Talbot S L, Karnovsky N J, Gabrielsen G W, Grémillet D, |
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Title |
Impacts of experimentally increased foraging effort on the family: offspring sex matters
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Journal Article |
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Year |
2009 |
Publication |
Animal Behaviour |
Abbreviated Journal |
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Volume |
78 |
Issue |
2 |
Pages |
321 -328 |
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Abstract |
We examined how short-term impacts of experimentally increased foraging effort by one parent reverberate around the family in a monomorphic seabird (little auk, Alle alle), and whether these effects depend on offspring sex. In many species, more effort is required to rear sons successfully than daughters. However, undernourishment may have stronger adverse consequences for male offspring, which could result in a lower fitness benefit of additional parental effort when rearing a son. We tested two alternative hypotheses concerning the responses of partners to handicapping parents via feather clipping: partners rearing a son are (1) more willing or able to compensate for the reduced contribution of their mate, or (2) less willing or able to compensate, compared to those rearing a daughter. Hypothesis 1 predicts that sons will be no more adversely affected than daughters, and the impact on parents will be greater when rearing a son. Hypothesis 2 predicts that sons will be more adversely affected than daughters, and parents raising a son less affected. Although experimental chicks of both sexes fledged in poorer condition than controls, sons attained higher mass and more rapid growth than daughters in both groups. Clipped parents lost a similar proportion of their initial mass regardless of chick sex, whereas partners of clipped birds lost more mass when rearing a son. These results support hypothesis 1: impacts of increased foraging effort by one parent were felt by offspring, regardless of their sex, and by the partners of manipulated birds, particularly when the offspring was male.
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388 |
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ISSN |
0003-3472 |
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yes |
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Serial |
2114 |
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Author |
Erica M. Lucas, Andrew A. Nyblade, Natalie J. Accardo, Andrew J. Lloyd, Douglas A. Wiens, Richard C. Aster, Terry J. Wilson, Ian W. Dalziel, Graham W. Stuart, John Paul O’Donnell, J. Paul Winberry, Audrey D. Huerta |
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Title |
Shear Wave Splitting Across Antarctica: Implications for Upper Mantle Seismic Anisotropy |
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Journal |
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Year |
2022 |
Publication |
Journal of Geophysical Research: Solid Earth |
Abbreviated Journal |
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Volume |
127 |
Issue |
4 |
Pages |
e2021JB023325 |
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Keywords |
anisotropy Antarctica shear wave splitting upper mantle |
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Abstract |
We examine upper mantle anisotropy across the Antarctic continent using 102 new shear wave splitting measurements obtained from teleseismic SKS, SKKS, and PKS phases combined with 107 previously published results. For the new measurements, an eigenvalue technique is used to estimate the fast polarization direction and delay time for each phase arrival, and high-quality measurements are stacked to determine the best-fit splitting parameters at each seismic station. The ensemble of splitting measurements shows largely NE-SW-oriented fast polarization directions across Antarctica, with a broadly clockwise rotation in polarization directions evident moving from west to east across the continent. Although the first-order pattern of NE-SW-oriented polarization directions is suggestive of a single plate-wide source of anisotropy, we argue the observed pattern of anisotropy more likely arises from regionally variable contributions of both lithospheric and sub-lithospheric mantle sources. Anisotropy observed in the interior of East Antarctica, a region underlain by thick lithosphere, can be attributed to relict fabrics associated with Precambrian tectonism. In contrast, anisotropy observed in coastal East Antarctica, the Transantarctic Mountains (TAM), and across much of West Antarctica likely reflects both lithospheric and sub-lithospheric mantle fabrics. While sub-lithospheric mantle fabrics are best associated with either plate motion-induced asthenospheric flow or small-scale convection, lithospheric mantle fabrics in coastal East Antarctica, the TAM, and West Antarctica generally reflect Jurassic—Cenozoic tectonic activity. |
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133 |
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2169-9356 |
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yes |
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Serial |
8322 |
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Kristin N. Barton, Nairita Pal, Steven R. Brus, Mark R. Petersen, Brian K. Arbic, Darren Engwirda, Andrew F. Roberts, Joannes J. Westerink, Damrongsak Wirasaet, Michael Schindelegger |
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Title |
Global Barotropic Tide Modeling Using Inline Self-Attraction and Loading in MPAS-Ocean |
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Journal |
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Year |
2022 |
Publication |
Journal of Advances in Modeling Earth Systems |
Abbreviated Journal |
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Volume |
14 |
Issue |
11 |
Pages |
e2022MS003207 |
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Keywords |
barotropic tides E3SM MPAS-Ocean numerical ocean modeling self-attraction and loading surface tides |
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Abstract |
We examine ocean tides in the barotropic version of the Model for Prediction Across Scales (MPAS-Ocean), the ocean component of the Department of Energy Earth system model. We focus on four factors that affect tidal accuracy: self-attraction and loading (SAL), model resolution, details of the underlying bathymetry, and parameterized topographic wave drag. The SAL term accounts for the tidal loading of Earth's crust and the self-gravitation of the ocean and the load-deformed Earth. A common method for calculating SAL is to decompose mass anomalies into their spherical harmonic constituents. Here, we compare a scalar SAL approximation versus an inline SAL using a fast spherical harmonic transform package. Wave drag accounts for energy lost by breaking internal tides that are produced by barotropic tidal flow over topographic features. We compare a series of successively finer quasi-uniform resolution meshes (62.9, 31.5, 15.7, and 7.87 km) to a variable resolution (45 to 5 km) configuration. We ran MPAS-Ocean in a single-layer barotropic mode forced by five tidal constituents. The 45 to 5 km variable resolution mesh obtained the best total root-mean-square error (5.4 cm) for the deep ocean (1,000 m) tide compared to TPXO8 and ran twice as fast as the quasi-uniform 8 km mesh, which had an error of 5.8 cm. This error is comparable to those found in other forward (non-assimilative) ocean tide models. In future work, we plan to use MPAS-Ocean to study tidal interactions with other Earth system components, and the tidal response to climate change. |
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688 |
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ISSN |
1942-2466 |
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yes |
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Call Number |
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Serial |
8572 |
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Author |
Techow NMSM, ORyan C, Phillips RA, Gales R, Marin M, Patterson-Fraser D, Quintana F, Ritz MS, Thompson DR, Wanless RM, Weimerskirch H, Ryan PG, |
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Title |
Speciation and phylogeography of giant petrels Macronectes
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Type |
Journal Article |
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Year |
2010 |
Publication |
Molecular Phylogenetics and Evolution |
Abbreviated Journal |
1055-7903 |
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Volume |
54 |
Issue |
2 |
Pages |
472-487 |
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Keywords |
Giant Petrels, Microsatellite, Cytochrome b, Macronectes, Genetic differentiation, Genetic diversity, Species, |
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Abstract |
We examine global phylogeography of the two forms of giant petrel Macronectes spp. Although previously considered to be a single taxon, and despite debate over the status of some populations and the existence of minimal genetic data (one mitochondrial cytochrome b sequence per form), the current consensus based on morphology is that there are two species, Northern Giant Petrel M. halli and Southern Giant Petrel M. giganteus. This study examined genetic variation at cytochrome b as well as six microsatellite loci in giant petrels from 22 islands, representing most island groups at which the two species breed. Both markers support separate species status, although sequence divergence in cytochrome b was only 0.42% (corrected). Divergence was estimated to have occurred approximately 0.2 mya, but with some colonies apparently separated for longer (up to 0.5 my). Three clades were found within giant petrels, which separated approximately 0.7 mya, with the Southern Giant Petrel paraphyletic to a monophyletic Northern Giant Petrel. There was evidence of past fragmentation during the Pleistocene, with subsequent secondary contact within Southern Giant Petrels. The analysis also suggested a period of past population expansion that corresponded roughly to the timing of speciation and the separation of an ancestral giant petrel population from the fulmar Fulmarus clade. |
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109 |
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1055-7903 |
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yes |
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Serial |
3059 |
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Author |
Peng Shushi, Ciais Philippe, Chevallier Frédéric, Peylin Philippe, Cadule Patricia, Sitch Stephen, Piao Shilong, Ahlström Anders, Huntingford Chris, Levy Peter, Li Xiran, Liu Yongwen, Lomas Mark, Poulter Benjamin, Viovy Nicolas, Wang Tao, Wang Xuhui, Zaehle Sönke, Zeng Ning, Zhao Fang, Zhao Hongfang, |
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Title |
Benchmarking the seasonal cycle of CO 2 fluxes simulated by terrestrial ecosystem models
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Type |
Journal Article |
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Year |
2015 |
Publication |
Global Biogeochemical Cycles |
Abbreviated Journal |
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Volume |
29 |
Issue |
1 |
Pages |
46-64 |
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Abstract |
We evaluated the seasonality of CO2 fluxes simulated by nine terrestrial ecosystem models of the TRENDY project against (1) the seasonal cycle of gross primary production (GPP) and net ecosystem exchange (NEE) measured at flux tower sites over different biomes, (2) gridded monthly Model Tree Ensembles-estimated GPP (MTE-GPP) and MTE-NEE obtained by interpolating many flux tower measurements with a machine-learning algorithm, (3) atmospheric CO2 mole fraction measurements at surface sites, and (4) CO2 total columns (XCO2) measurements from the Total Carbon Column Observing Network (TCCON). For comparison with atmospheric CO2 measurements, the LMDZ4 transport model was run with time-varying CO2 fluxes of each model as surface boundary conditions. Seven out of the nine models overestimate the seasonal amplitude of GPP and produce a too early start in spring at most flux sites. Despite their positive bias for GPP, the nine models underestimate NEE at most flux sites and in the Northern Hemisphere compared with MTE-NEE. Comparison with surface atmospheric CO2 measurements confirms that most models underestimate the seasonal amplitude of NEE in the Northern Hemisphere (except CLM4C and SDGVM). Comparison with TCCON data also shows that the seasonal amplitude of XCO2 is underestimated by more than 10% for seven out of the nine models (except for CLM4C and SDGVM) and that the MTE-NEE product is closer to the TCCON data using LMDZ4. From CO2 columns measured routinely at 10 TCCON sites, the constrained amplitude of NEE over the Northern Hemisphere is of 1.6 ± 0.4 gC m−2 d−1, which translates into a net CO2 uptake during the carbon uptake period in the Northern Hemisphere of 7.9 ± 2.0 PgC yr−1. |
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416 |
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0886-6236 |
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yes |
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Call Number |
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Serial |
6043 |
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Author |
Merrer, S.; Cara, M.; Rivera, L.; Ritsema, J. |
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Title |
Upper mantle structure beneath continents: New constraints from multi-mode Rayleigh wave data in western North America and southern Africa |
Type |
Journal Article |
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Year |
2007 |
Publication |
Geophysical research letters |
Abbreviated Journal |
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Volume |
34 |
Issue |
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Pages |
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Keywords |
Rayleigh waves; upper mantle; 7208 Seismology: Mantle; 7255 Seismology: Surface waves and free oscillations; 7290 Seismology: Computational seismology |
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Abstract |
We estimate the averaged 1-D shear-wave velocity of the upper mantle beneath western North America and the Kaapvaal region in southern Africa by inverting dispersion measurements of fundamental and higher Rayleigh modes recorded by ?2000 km aperture broadband arrays. The overtones at periods exceeding 25 s constrain the averaged 1-D shear-wave velocity to 650 km depth across the regional arrays. Our overtone analysis confirms the shear-wave velocity differences observed in global tomographic models with similar horizontal resolution: the western North American mantle features a prominent low velocity zone at depths 50–200 km, while the shear velocity in the upper 180–200 km of the mantle beneath southern Africa is at least 6% higher than in western North America which we interpret as the expression of a cratonic keel. There is no resolvable difference in shear-wave velocity between southern Africa and western North America below a depth of about 300 km. |
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133;906 |
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American Geophysical Union |
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0094-8276 |
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yes |
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IPEV @ Thierry.Lemaire @ |
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5540 |
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