dataesr/scientific-paragraphs-categorization huggingface dataset:
, 1997; Sapart et al. , 2013). A two-step approach was adopted in this study in order to explore the interplay between non-modeled uncertainties and mathematical underdetermination of the problem: reasonably smooth scenarios are tested through all available data sets and models. This allows us to indirectly take into account model uncertainties based on the use of both the IN-STAAR and LGGE-GIPSA models and possible geographic variations of [CO] between the three modeled Greenland sites. First, families of scenarios (with different regularization terms) were generated using data and the transfer functions from both models for all individual sites, as well as using multisite reconstructions. All scenarios were then tested by convolution with all available transfer functions; for the NEEM boreholes the scenarios were tested with transfer functions from both the INSTAAR and LGGE-GIPSA forward models, for Summit and NGRIP with transfer functions from the LGGE-GIPSA model only.
We allowed a single exception to the "all data points below 40 m must be matched" rule for the NGRIP data point at 42. 6 m depth. The deseasonalized atmospheric trend at Barrow shows an important anomaly in 1998-1999 (see Fig. 1 ), which is likely due to a large biomass burning event (e. g. ,  van der Werf et al. , 2006). Forward model tests showed a strong impact of this anomaly on concentrations in firn down to the lock-in depth at NGRIP, which was sampled in 2001. Thus the inability of the model to produce scenarios that match the NGRIP data point at 42. 6 m depth is likely due to this brief anomaly. Without this exception, a large number of reconstructed CO scenarios would be excluded (Fig. S4 ). Excluding these scenarios would not significantly affect our overall scenario envelope, as other very similar scenarios are not excluded (Fig.
S4 ). However, most of the two-site scenarios based on NEEM EU + NEEM US data would be excluded. As overall the firn at NEEM is probably the best characterized of all sites (more species, replicate measurements from more labs and overall more recent, higher-quality analyses), we decided to make the exception for this data point to retain the NEEM-based scenarios. A combined root-mean-square deviation (RMSD) value was calculated for each scenario after convolutions with all the transfer functions for all sites. To produce a reasonable number of final scenarios, we accepted scenarios that were not more than 15 % higher in their RMSD than the best RMSD scenario. Some scenarios generated with low values of the regularization term (visibly too irregular) were still able to pass the data-model comparison test, indicating that even a multisite approach with two models still left the inverse problem underdetermined.
Summary and conclusions We have presented the first firn air record of past atmospheric  [CO]  for the NH high latitudes, covering the period from 1950 to 2008. The good agreement among [CO] records from three different firn air sites (NEEM, NGRIP and Summit) confirms that CO is well preserved in the firn at inland Greenland sites. The quality of the firn air records is further confirmed by the good agreement with direct atmospheric measurements of  [CO]  in the Arctic, which began in 1980. Peak-shaped atmospheric trends are challenging to reconstruct from firn air data due to the smoothing effect of molecular diffusion. A new methodology for this reconstruction V. V. Petrenko et al. : A 60 yr record of atmospheric carbon monoxide has been developed and its robustness tested. Different firn gas transport models, combinations of firn air sites and optimal solution definitions lead to consistent results for [CO] peak height and constrain the [CO] peak date with ≈ ±6 year uncertainty.
Acknowledgements. This project was supported by the  NOAA Postdoctoral Fellowship in Climate and Global Change (Petrenko)  and  US NSF   Awards 0632222  and  0806387  (White) and 0520460 (Battle). NEEM is directed and organized by the  Center of Ice and Climate at the Niels Bohr Institute  and  US NSF, Office of Polar Programs. It is supported by funding agencies and institutions in Belgium (FNRS-CFB and FWO),  Canada (NRCan/GSC), China (CAS) ,  Denmark (FIST), France (IPEV, CNRS/INSU, CEA and ANR) ,  Germany (AWI) ,  Iceland (RannIs), Japan (NIPR) ,  Korea (KOPRI) , the  Netherlands (NWO/ALW), Sweden (VR) ,  Switzerland (SNF) ,  United Kingdom (NERC)  and the  USA (US NSF, Office of Polar Programs). CSIRO 's contribution was undertaken as part of the  Australian Climate Change Science Program , funded jointly by the  Department of Climate Change and Energy Efficiency , the  Bureau of Meteorology and CSIRO.
The project was also funded by the  UK NERC  Grant  NE/F021194/1  (UEA). The  CESM  project is supported by the  US NSF  and the  Office of Science (BER)  of the  US Department of Energy. The  National Center for Atmospheric Research  is operated by the  University Corporation for Atmospheric Research  under sponsorship of the  National Science Foundation. We thank the  NEEM team, CPS Polar  and the 109th Air National Guard for field logistical support. UEA would like to thank  Carl Brenninkmeijer  ( MPI Mainz, Germany ) for providing a metal bellows pump and custom-built compressor for large volume firn air samples. We thank  Aslam Khalil  for providing OGI [CO] data. This manuscript was improved by constructive reviews from  Maarten Krol  and one anonymous reviewer. Edited by:  R. van de Wal.
Myoanatomical features of adult and Higgins larva stage observed by light (LM) or transmission electron microscopy (TEM). renaudae, and the radial muscles attached to the furcal base of the mouth cone were not found in any of the recently investigated species (for more details see Table  1 ). As for the body musculature of the Higgins larva, the available data is scarce and comes solely from light microscopy observations on P. pedicularis and R. doliolius  [10, 16]. Both species possess longitudinal and circular muscles in the abdomen region, but the mouth cone and head longitudinal muscles were found only in the latter species (for more details see Table  1 ). Furthermore, no radial/circular muscles were found in the mouth cone or introvert in any of these two species. In addition, the Higgins larva of R.
Confocal Laser Scanning Microscopy (CLSM) and 3D reconstruction The total number of specimens investigated was 11 adult Nanaloricus sp. and 2 Higgins larvae of Armorloricus elegans. The fluorescence preparations were analyzed with a Leica DM 5000 CS microscope equipped with a Leica DM 5000 SP5 confocal laser scanning unit. Alternatively, a Zeiss LSM700 confocal mounted on a Zeiss Axio Imager upright microscope was used to perform the analysis. The resulting image stacks were surface-rendered with the image editing software Imaris v. 7. 5. 0 (Bitplane AG, Zürich, Switzerland) to create the 3D models. Additionally, the specimens embedded for CLSM were also studied using a Leica DM6000 B light microscope with phasecontrast and DIC optics. and drafted the manuscript. HR acquired funding for the materials, participated in the conception of the study, collected the animals and revised the manuscript.
Acknowledgments We are grateful to the technical support by the staff from the  Marine Station of Roscoff , especially  Gilles Maron  and  Sophie Le Panse  for their crucial help during field collection and permission to use the CLSM, respectively. Funding to support the collection in Roscoff was provided by  EU  programme  ASSEMBLE- grant agreement no. 227799. Fernando Pardos  (Madrid),  Iben Heiner  (Copenhagen) and  Andreas Schmidt-Rhaesa (Hamburg)  are acknowledged for many discussions on the subject. The first author also greatly appreciated the generous support by the staff from the  Imaging Core Facility of the Biozentrum -University of Basel.
Time Asia is here defined as the continental area east of a line running from the Ural Mountains southward to the Caucasus and then westwards to the Bosporus. Greenland is here included in Europe, as it was a part of that continent during that time. We investigated the palaeogeographic distribution of fossilised wood assemblages containing Xenoxylon specimens. For this purpose, we merged data, on the basis of geographic origin, into twenty-two super-localities (Table  1 ). Data sources. -For this study, we performed a literature survey for Mesozoic fossilised wood, limiting ourselves to the assemblages that included Xenoxylon. We considered only fossilised wood data that were based on isolated secondary xylem (tracheidoxyls). Some unpublished data were also used, either established by samples sent by colleagues (see acknowledgments section), or obtained while revising collections at HMB, NHMD, BMNH, BIN, TUMS, SMNH, and NCU.
To avoid redundancy, data in the database are understood to represent the occurrence of a fossil genus in a geological formation, not taking into account if this genus (or a synonym) had been reported several times from that formation, in one or several localities. Stratigraphically uncertain data were not considered for our study, specifically, the reworked fossilised wood assemblages from the Mekong River terraces (Vozenin-Serra and Privé-Gill 1991), or the loose wood assemblage from the Choshi area  (Nishida et al. 1993). Several Mesozoic fossilised wood data points, particularly from China, are poorly age constrained. Geological formations were sometimes renamed after the original publication, or their age was reappraised. For Chinese data, we generally followed the recent review of  Zheng et al.
However, examination by  Philippe and Hayes (2010: 59-60 ) of a topotype for Araucariopitys revealed that this latter name should be used only for short shoots with preserved pith and araucarioid cross-fields, while Protocedroxylon should be used for tracheidoxyls with a clearly mixed type of radial pitting and few spaced taxodioid oculipores in the cross-fields. Some Araucariopitys species have been mentioned in our database, but all can be reassigned to Protocedroxylon. Consequently, we used Protocedroxylon here as the correct name for the data originally published for the study area and interval as Cedroxylon, Metacedroxylon, Protocedroxylon, and Araucariopitys. In the case of araucaria-like fossilised woods (i. e. , tracheidoxyls with araucarian radial pitting and araucarioid cross-field pitting, lacking Abietineentüpfelung and resin canals), many different names have been used until now (e.
g. , Araucarioxylon  Kraus, 1870 , Dadoxylon Endlicher, 1847 , Agathoxylon Hartig, 1848 , Dammaroxylon Schultze-Motel, 1966). Recently, the wood anatomist community was polled to clarify which name should be retained for araucaria-like fossilised wood  (Rößler et al. 2014 ). In accordance with the conclusions from this poll, we used Agathoxylon here. Despite these preliminary taxonomic reappraisals, the discrepancies between the systematic approaches of the various authors still obscured our database. Indeed, the same wood specimen can be assigned to different genera by different authors according to their taxonomic choices, e. g. , a typical Podocarpoxylon  Gothan, 1906 , could be assigned to Taxodioxylon or to Circoporoxylon Kräusel, 1949 (see e. g. , Müller-Stoll and Schultze-Motel 1989).
It was considered to be too risky to revise all of the systematic attributions in the database only on the basis of the publications, without checking the types. Thus, to limit the taxonomical bias, during a second stage of data management, we chose to merge the data into seven informal taxonomical groups (Table  2 ), uniting similar-appearing genera. Group A (or the Protocedroxylon group) was for wood with Abietineentüpfelung, most likely related to the Pinaceae. Wood that resembled the extant Cupressaceae sensu lato was assigned here to group B (or the Taxodioxylon group). Group C (or the Phyllocladoxylon group) was for wood specimens with unbordered (or slightly bordered) oopores, which have unclear systematic affinities. Group D (the Podocarpoxylon group) contains wood specimens with taxodioid to podocarpoid oopores in the early wood cross-fields, and these mostly also have unclear systematic positions.
Evolution of the diversity of Xenoxylon-taphocoenoses. - For the Late Triassic, the fossilised wood assemblages containing Xenoxylon have a low diversity globally (3 genera) (Fig. 4 ). After the Triassic, the global generic diversity of Xenoxylon-taphocoenoses increased to 27 genera for the Early to Middle Jurassic interval, as shown in Fig. 4 , with a well distributed share for the different genera, although the Protocedroxylon group (A), the Podocarpoxylon group (D), and Agathoxylon (E) are co-dominant (Fig. 3 ). The diversity remained high (28 genera) during the Late Jurassic to Early Cretaceous interval, but the contributions from groups D, E, and F decreased, in favour of those from groups B (Taxodioxylon group) and C (Phyllocladoxylon group) (Figs. 3, 4 ). For the Late Cretaceous, the number of associations reported in the database is low (Fig.
Our data originate from taphocoenoses, which represent the post-mortem gathering of fossilised wood pieces. There is a little evidence from in situ fossilised wood floras that include Xenoxylon  (Shimakura 1936; Ogura et al. 1951; Wang et al. 2000) , with Protopiceoxylon (a type of wood from the Protocedroxylon group) being reported in  Wang et al. (2000). Nevertheless, the fact that, among fossilised wood assemblages, Protocedroxylon co-occurs with Xenoxylon more than eight times more than with any other fossilised wood genus from the Late Triassic to the Late Cretaceous demonstrates that Protocedroxylon was a component of the Xenoxylon-phytocoenoses. The results for the other genera are not as conclusive. From our data, it is impossible to assert that Xenoxylon was growing locally in exclusive stands.
By the Late Cretaceous, the diversity of Xenoxylon-floras decreased and their distribution was reduced. 2 ). Xenoxylon-phytocoenoses and palaeoclimates. -The Pangaean supercontinent became fragmented during the Triassic, while the climate remained warm and dry globally. It is noteworthy that Xenoxylon-phytocoenoses appeared worldwide during the Carnian, with Protocedroxylon as an associated element, during a time that might correspond to a cooling and pluvial event  (Simms and Ruffell 1989). Continents became increasingly separated during the Early Jurassic, while concomitantly, the world climate became more equable and more humid than during the Triassic  (Chandler et al. 1992; Golonka and Ford 2000; Ruckwied and Götz 2009). Such a globally more humid climatic environment was most likely the primary cause of the spread and the increase in the diversity of the Xenoxylon-phytocoenoses.
Acknowledgements Thanks are owed to  Marion Bamford  ( University of the Witwatersrand, Johannesburg, South Africa ),  Fabrice Malartre  ( Ecole Nationale Supérieure de Géologie, Nancy, France ),  Kazuo Terada  ( Fukui Prefectural Dinosaur Museum, Fukui, Japan ),  Wu Zhang  ( Shenyang Institute of Geology and Mineral Resources, Ministry of Land and Resources, Shenyang, PR China ),  Shaolin Zheng  ( Shenyang Institute of Geology and Mineral Resources, Ministry of Land and Resources, Shenyang, PR China ), and an anonymous reviewer for constructive discussions. Our thanks also go to  Maria Doludenko  ( Geology Institute, Moscow, Russia ),  Leszek Marynowski  ( University of Silesia, Sosnowiec, Poland ),  Frank Wittler  ( Karlsruhe University, Germany ), and  Michał Zatoń  ( University of Silesia, Sosnowiec, Poland ), who donated specimens; and to  Peta Hayes  ( Natural History Museum, London, UK ),  David Cantrill  ( Royal Botanic Gardens Melbourne, Melbourne, Australia ),  Gilles Cuny  ( Natural History Museum of Denmark, Copenhagen ,.
For notational simplicity, the TOA notation is dropped hereafter. For the present research a simulated dataset of ρ rc (λ ) is build by combining the 105 in situ ρ w (λ ) spectra (from above water TRIOS Ramses hyper-spectral radiometers, further detailed in the companion paper of this study  [12] ) with a simplified power law model for the multiplescattering aerosol reflectance, ρ am (λ 0 ) (the sum of ρ a (λ 0 ) and ρ ra (λ 0 ) in Eq. (  1 )): ρ am (λ ) = ρ am (λ 0 ) λ λ 0 -η (2) with η being the Ångström coefficient for the aerosol reflectance. For these tests we set the atmospheric diffuse transmittances, t θ v (λ ) and t θ 0 (λ ), to 1 and simulate ρ rc (λ ) simply as the sum of ρ am (λ ) and the in situ ρ w (λ ). As shown by the flowchart in Fig. 1 , ρ rc (λ ) is then inverted using either the STD or the MUMM algorithm to estimate ρ w (λ ) which for a perfect model would be equal to the in situ ρ w (λ ).
10 -3 and superior to 3. 10 -3 , respectively. All spectra presented ρ w (λ NIR ) values above 10 -4 , which is approximately the upper limit for which the GW94 AC algorithm can be successfully applied  [2]. Out of the 105 spectra, 53% present moderate turbidity with ρ w (869) ranging from 10 -4 to 3. 10 -3 and 47% of the data present very turbid waters with ρ w (869) exceeding 3. 10 -3. This latter value corresponds to the threshold used by Wang et al. [10]  to switch for the SWIR algorithm in the combined NIR-SWIR GW94-based AC process. Among the very turbid waters, extremely turbid waters are also investigated. These are water masses presenting ρ w (869) values superior to 10 -2 and represent about 23% of the total in situ dataset.
Acknowledgements. This study has been funded by  CNES  ( Centre National d' Études Spatiales) ,  CNRS  ( Centre National de la Acknowledgements. This study has been funded by  CNES  ( Centre National d' Études Spatiales) ,  CNRS  ( Centre National de la Recherche Scientifique ), the  University of Lille , and  Région Nord-Pas-de-Calais. Y. Karol is supported by a fellowship from  CNES  and  CNRS. PLASMA calibration was performed at Izaña observatory using AERONET-EUROPE calibration center, supported by  ACTRIS  from  European Union   Seventh Framework Program  ( FP7/2007-2013)  under grant agreement no. 262254. Emilio Cuevas-Agullo  from the  Meteorological State Agency of Spain (AEMET)  is acknowledged for his help during the experiment in Tenerife. The authors are very thankful to AERONET for establishing and maintaining the sites used in this work.
ISGI had then to face up two challenges: -establish a policy for on-line dissemination of indices; -ensure a quasi real time on-line dissemination of reliable quick-look values of IAGA geomagnetic indices. ISGI decided to routinely make available on-line preliminary values for almost all IAGA geomagnetic indices. ISGI also drove discussions in the frame of IAGA. They resulted in an IAGA resolution urging the producers of estimated indices to make clear by a specific label that they are not official IAGA indices. The ISGI label thus appeared to be the simplest and the safest way to ensure the quality stamping of circulated geomagnetic indices, and the ISGI Collaborating Institutes therefore decided to quote their ISGI membership in all their publications and data bases. This ISGI contribution is used to illustrate the role that a WDS service could play as a provider of reference values for given quantities, and to highlight the need for such reference data services.
The 11-year solar cycle is clearly depicted by the sunspot number data series. It also modulates the geomagnetic activity, although in a more complex way. The geomagnetic activity is minimum during the periods of minimum solar activity. Then it increases during the ascending phase of the solar cycle and reaches a maximum during the years where the sunspot number is maximum. A secondary maximum of geomagnetic activity is observed during the descending phase of the solar cycle: this secondary maximum corresponds to solar activity related to the onset of the following cycle (see, e. g. ,  Legrand and Simon, 1991 and references therein). The variations of the 20-years running average of geomagnetic activity show that long-term variations are superimposed to those related to the solar cycle: the average level of activity remained quite low between 1868 and about 1925, while it was quite high since the beginning of the 1950's.
This situation, which results from the very complex morphology of geomagnetic activity, implies the existence of an organization, the International Service of Geomagnetic Indices (ISGI), with the mission to calculate, to make available to the scientific community, and to maintain archives of reference values for the IAGA geomagnetic indices, and to take advantage of its expertise in this area to serve the scientific community ISGI is a kind of network that brings together the activities of the four institutionscalled ISGI Collaborating Institutesthat are responsible for calculating and disseminating IAGA Geomagnetic Indices: the LATMOS, the Data Analysis Center for geomagnetism and Space Magnetism (Kyoto, Japan), the GeoForschungZentrum Potsdam (GFZ, Potsdam, Germany) and the Observatori de l'Ebre (Roquetes, Spain).
Current ISGI activities The primary responsibility of ISGI is the calculation, distribution and archiving of reference values for IAGA geomagnetic indices. As already mentioned, each ISGI Collaborating Institutes is responsible for calculating, disseminating and archiving one or several IAGA Geomagnetic Indices. ISGI headquarters are, as such, responsible for: -maintaining and updating of the Internet ISGI homepage. This site is designed as a portal to all sites of collaborating institutes. Together with the these sites, it provides reference values of IAGA geomagnetic indices; -promoting the participation of ISGI to networks which aims to facilitate user access to all necessary data in the physics of solar-terrestrial relations; -publishing and distributing a Monthly Bulletin that disseminates provisional values of IAGA geomagnetic indices.
From the user's point of view, the crucial question became: how to be sure of the quality of geomagnetic indices that I find on Internet? This could have resulted in a dramatic loss of confidence of users in the quality of geomagnetic indices made available through Internet. Such a loss of confidence would have in turn challenged the possibility to continue the production of high quality long term data series. This made it clear the necessity for a policy for on-line dissemination of indices, and for quasi real time on-line dissemination of reliable preliminary values of IAGA geomagnetic indices. ISGI Collaborating Institutes then decided to routinely make available on-line state of the art preliminary values (few hours to two days delay for all IAGA geomagnetic indices, since 1996 for most of them; 30 min delay since 2004 for the aa index).
In parallel, ISGI led discussions within IAGA. IAGA resolved that the reference values of geomagnetic indices are those produced by the ISGI Collaborating Institutes, and that they must be posted first at the ISGI and ISGI Collaborating Institutes homepages. IAGA also took a resolution urging the "producers of the estimated indices to clearly label them with "est" at the end of each index name to distinguish them from the official IAGA indices" (Resolution 5, IAGA  News 38 1998, p. 42). This policy succeeded both in fitting with this new environment and in preserving the historical heritage, namely the high quality, homogeneous long term data series. This policy is still in force.