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Martian magmatism from plume metasomatized mantle

Impact:
The distinctive nature of martian meteorites to remotely sensed martian surface samples, in particular the higher alkali contents of some Gusev and Gale crater samples, possibly implies that alkali volcanism on Mars is driven by low-degree partial melting from metasomatism of martian lithosphere in response to mantle plume impingement, offering a mechanism for explaining the apparent differences observed between meteorites and mission data for Mars.

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  • DeAngelis A.I, Stanistreet J.E, Baumann-Pickering S., Cholewiak D.M.  2018.  A description of echolocation clicks recorded in the presence of True's beaked whale (Mesoplodon mirus). Journal of the Acoustical Society of America. 144:2691-2700.
    Abstract Summary:

    True's beaked whales (Mesoplodon mirus) were encountered on two separate shipboard surveys on 24 July 2016 and 16 September 2017 in the western North Atlantic Ocean. Recordings were made using a hydrophone array towed 300m behind the ship. In 2016, three different groups were sighted within 1500m of the ship; clicks were recorded for 26 min. In 2017, a single group of five whales was tracked over the course of five hours in which the ship...

  • Loizeau M., Buteau S., Chaix B., McElroy S., Counil E., Benmarhnia T..  2018.  Does the air pollution model influence the evidence of socio-economic disparities in exposure and susceptibility? Environmental Research. 167:650-661.
    Abstract Summary:

    Studies assessing socio-economic disparities in air pollution exposure and susceptibility are usually based on a single air pollution model. A time stratified case-crossover study was designed to assess the impact of the type of model on differential exposure and on the differential susceptibility in the relationship between ozone exposure and daily mortality by socio-economic strata (SES) in Montreal. Non-accidental deaths along with deaths...

  • Jackson R.H, Lentz S.J, Straneo F.  2018.  The dynamics of shelf forcing in Greenlandic Fjords. Journal of Physical Oceanography. 48:2799-2827.
    Abstract Summary:

    The fjords that connect Greenland's glaciers to the ocean are gateways for importing heat to melt ice and for exporting meltwater into the ocean. The transport of heat and meltwater can be modulated by various drivers of fjord circulation, including freshwater, local winds, and shelf variability. Shelf-forced flows (also known as the intermediary circulation) are the dominant mode of variability in two major fjords of east Greenland, but we...

  • Smith KL, Ruhl H.A, Huffard C.L, Messie M., Kahru M.  2018.  Episodic organic carbon fluxes from surface ocean to abyssal depths during long-term monitoring in NE Pacific. Proceedings of the National Academy of Sciences of the United States of America. 115:12235-12240.
    Abstract Summary:

    Growing evidence suggests substantial quantities of particulate organic carbon (POC) produced in surface waters reach abyssal depths within days during episodic flux events. A 29-year record of in situ observations was used to examine episodic peaks in POC fluxes and sediment community oxygen consumption (SCOC) at Station M (NE Pacific, 4,000-m depth). From 1989 to 2017, 19% of POC flux at 3,400 m arrived during high-magnitude episodic events...

  • Li Q., Lee S., Mazloff M..  2018.  Evidence of jet-scale overturning ocean circulations in Argo float trajectories. Geophysical Research Letters. 45:11866-11874.
    Abstract Summary:

    In a recent study, it was proposed that Reynolds stress by oceanic mesoscale eddies not only drives jets such as Subantarctic Front but also can force overturning circulations that are composed of rising motion on the poleward flank and sinking motion on the equatorward flank of the jets. In that study, the thermally indirect, jet-scale overturning circulations (JSOCs) were detected in an eddy-resolving model simulation of the Southern Ocean...

  • Guest J.R, Edmunds P.J, Gates R.D, Kuffner I.B, Andersson AJ, Barnes B.B, Chollett I., Courtney T.A, Elahi R., Gross K. et al..  2018.  A framework for identifying and characterising coral reef "oases" against a backdrop of degradation. Journal of Applied Ecology. 55:2865-2875.
    Abstract Summary:

    1. Human activities have led to widespread ecological decline; however, the severity of degradation is spatially heterogeneous due to some locations resisting, escaping, or rebounding from disturbances. 2. We developed a framework for identifying oases within coral reef regions using long-term monitoring data. We calculated standardised estimates of coral cover (z-scores) to distinguish sites that deviated positively from regional means. We...

  • Day JMD.  2018.  Geochemical constraints on residual metal and sulfide in the sources of lunar mare basalts. American Mineralogist. 103:1734-1740.
    Abstract Summary:

    Low oxygen fugacity (f(O2)) in the lunar interior (one log unit below the iron-wustite buffer inverted right perpendicular IW-1 inverted left perpendicular) offers the possibility that stable Fe-metal and sulfide phases exist as restites within lunar mare basalt source regions. Metal and sulfide phases have high metal-melt and sulfide-melt partition coefficients for chalcophile, siderophile (> 100), and highly siderophile elements (>...

  • Goldberg D.E, Melgar D, Bock Y, Allen R.M.  2018.  Geodetic observations of weak determinism in rupture evolution of large earthquakes. Journal of Geophysical Research-Solid Earth. 123:9950-9962.
    Abstract Summary:

    The moment evolution of large earthquakes is a subject of fundamental interest to both basic and applied seismology. Specifically, an open problem is when in the rupture process a large earthquake exhibits features dissimilar from those of a lesser magnitude event. The answer to this question is of importance for rapid, reliable estimation of earthquake magnitude, a major priority of earthquake and tsunami early warning systems. Much effort...

  • Fox M.D, Williams GJ, Johnson M.D, Radice V.Z, Zgliczynski B.J, Kelly E.LA, Rohwer F.L, Sandin SA, Smith JE.  2018.  Gradients in primary production predict trophic strategies of mixotrophic corals across spatial scales. Current Biology. 28:3355-+.
    Abstract Summary:

    Mixotrophy is among the most successful nutritional strategies in terrestrial and marine ecosystems. The ability of organisms to supplement primary nutritional modes along continua of autotrophy and heterotrophy fosters trophic flexibility that can sustain metabolic demands under variable or stressful conditions. Symbiotic, reef-building corals are among the most broadly distributed and ecologically important mixotrophs, yet we lack a basic...

  • Zhou W.Y, Xie SP.  2018.  A hierarchy of idealized monsoons in an intermediate GCM. Journal of Climate. 31:9021-9036.
    Abstract Summary:

    A hierarchy of idealized monsoons with increased degrees of complexity is built using an intermediate model with simplified physics and idealized land-sea geometry. This monsoon hierarchy helps formulate a basic understanding about the distribution of the surface equivalent potential temperature (e), which proves to provide a general guide on the monsoon rainfall. The zonally uniform monsoon in the simplest aquaplanet simulations is explained...

  • Minich J.J, Humphrey G., Benitez R.AS, Sanders J., Swofford A., Allen EE, Knight R..  2018.  High-throughput miniaturized 16S rRNA amplicon library preparation reduces costs while preserving microbiome integrity. mSystems. 3
    Abstract Summary:

    Next generation sequencing technologies have enabled many advances across biology, with microbial ecology benefiting primarily through expanded sample sizes. Although the cost of running sequencing instruments has decreased substantially over time, the price of library preparation methods has largely remained unchanged. In this study, we developed a low-cost miniaturized (5-mu l volume) high-throughput (384-sample) amplicon library...

  • Rodenbeck C, Zaehle S., Keeling R., Heimann M..  2018.  History of El Nino impacts on the global carbon cycle 1957-2017: a quantification from atmospheric CO2 data. Philosophical Transactions of the Royal Society B-Biological Sciences. 373
    Abstract Summary:

    Interannual variations in the large-scale net ecosystem exchange (NEE) of CO2 between the terrestrial biosphere and the atmosphere were estimated for 1957-2017 from sustained measurements of atmospheric CO2 mixing ratios. As the observations are sparse in the early decades, available records were combined into a 'quasi-homogeneous' dataset based on similarity in their signals, to minimize spurious variations from beginning or ending data...

  • Spackeen J.L, Sipler R.E, Bertrand E.M, Xu K., McQuaid J.B, Walworth N.G, Hutchins D.A, Allen A.E, Bronk D.A.  2019.  Impact of temperature, CO2, and iron on nutrient uptake by a late-season microbial community from the Ross Sea, Antarctica. Aquatic Microbial Ecology. 82:145-159.
    Abstract Summary:

    The Southern Ocean is rapidly changing as a result of rising sea surface temperatures, elevated CO2 concentrations, and modifications to iron sources and sinks. The Southern Ocean has seasonally high rates of primary production, making it critical to determine how changes will impact biogeochemical rate processes in this important sink for CO2. During the austral summer, we measured nitrogen and carbon uptake rates by a late-season Ross Sea...

  • Brennan R.S, Healy T.M, Bryant H.J, Van La M., Schulte P.M, Whitehead A..  2018.  Integrative population and physiological genomics reveals mechanisms of adaptation in killifish. Molecular Biology and Evolution. 35:2639-2653.
    Abstract Summary:

    Adaptive divergence between marine and freshwater (FW) environments is important in generating phyletic diversity within fishes, but the genetic basis of this process remains poorly understood. Genome selection scans can identify adaptive loci, but incomplete knowledge of genotype-phenotype connections makes interpreting their significance difficult. In contrast, association mapping (genome-wide association mapping [GWAS], random forest [RF]...

  • Stukel M.R, Biard T., Krause J., Ohman MD.  2018.  Large Phaeodaria in the twilight zone: Their role in the carbon cycle. Limnology and Oceanography. 63:2579-2594.
    Abstract Summary:

    Advances in in situ imaging allow enumeration of abundant populations of large Rhizarians that compose a substantial proportion of total mesozooplankton biovolume. Using a quasi-Lagrangian sampling scheme, we quantified the abundance, vertical distributions, and sinking-related mortality of Aulosphaeridae, an abundant family of Phaeodaria in the California Current Ecosystem. Inter-cruise variability was high, with average concentrations at...

  • Highlighted Publication Fine-scale estimates of the average diffusivity
    Whalen C.B, MacKinnon JA, Talley LD.  2018.  Large-scale impacts of the mesoscale environment on mixing from wind-driven internal waves. Nature Geoscience. 11:842-+.
    Abstract Summary:

    Oceanic mesoscale structures such as eddies and fronts can alter the propagation, breaking and subsequent turbulent mixing of wind-generated internal waves. However, it has been difficult to ascertain whether these processes affect the global-scale patterns, timing and magnitude of turbulent mixing, thereby powering the global oceanic overturning circulation and driving the transport of heat and dissolved gases. Here we present global...

  • Highlighted Publication Overview of the SF‐SS system
    Slater D.A, Straneo F, Das S.B, Richards C.G, Wagner T.JW, Nienow P.W.  2018.  Localized plumes drive front-wide ocean melting of a Greenlandic tidewater glacier. Geophysical Research Letters. 45:12350-12358.
    Abstract Summary:

    Recent acceleration of Greenland's ocean-terminating glaciers has substantially amplified the ice sheet's contribution to global sea level. Increased oceanic melting of these tidewater glaciers is widely cited as the likely trigger, and is thought to be highest within vigorous plumes driven by freshwater drainage from beneath glaciers. Yet melting of the larger part of calving fronts outside of plumes remains largely unstudied. Here we...

  • Valdez-Grijalva M.A, Muxworthy A.R, Williams W., Conbhui P.O, Nagy L., Roberts A.P, Heslop D..  2018.  Magnetic vortex effects on first-order reversal curve (FORC) diagrams for greigite dispersions. Earth and Planetary Science Letters. 501:103-111.
    Abstract Summary:

    First-order reversal curve (FORC) diagrams are used increasingly in geophysics for magnetic domain state identification. The domain state of a magnetic particle is highly sensitive to particle size, about which FORC diagrams provide valuable information. However, the FORC signal of particles with nonuniform magnetisations, which are the main carrier of natural remanent magnetisations in many systems, is still poorly understood. In this study...

  • Highlighted Publication
    Day JMD, Tait KT, Udry A, Moynier F, Liu Y, Neal CR.  2018.  Martian magmatism from plume metasomatized mantle. Nature Communications. 9:4799.
    Abstract Summary:

    Direct analysis of the composition of Mars is possible through delivery of meteorites to Earth. Martian meteorites include ∼165 to 2400 Ma shergottites, originating from depleted to enriched mantle sources, and ∼1340 Ma nakhlites and chassignites, formed by low degree partial melting of a depleted mantle source. To date, no unified model has been proposed to explain the petrogenesis of these distinct rock types, despite their importance for...

  • Abstract Summary:

    The spatial and temporal evolution of Middle East and southwest Asia (MESW) precipitation characteristics and the associated atmospheric circulation during times in which tropical eastern Indian Ocean precipitation is either enhanced or reduced associated with the Madden-Julian oscillation (MJO) is assessed. Using multiple estimates of both the observed precipitation and the MJO during 1981-2016, the evolution of MESW precipitation...

  • Hedlin MAH, Ritsema J., de Groot-Hedlin C.D, Hetland E.A.  2018.  A multidisciplinary study of the 17 January 2018 bolide terminal burst over southeast Michigan. Seismological Research Letters. 89:2183-2192.
    Abstract Summary:

    A meteor that burst above Michigan in early 2018 was recorded by nearby seismometers, regional infrasonic microphones, and optical sensors. The relatively large, but sparse, infrasonic network provided a location and time for the event that was consistent with ground-truth data from the optical sensors, although uncertainty regarding the infrasonic location was large. Seismic arrival times from four local seismometers constrain the location...

  • Abstract Summary:

    A recent study used 61 extant animal genomes to reconstruct the chromosomes of the hypothetical amniote ancestor. Comparison of this karyotype to the 17 chordate linkage groups previously inferred in the ancestral chordate indicated that two whole genome duplications probably occurred in the lineage preceding the ancestral vertebrate.


  • Castro-Falcon G., Millan-Aguinaga N., Roullier C., Jensen PR, Hughes CC.  2018.  Nitrosopyridine probe to detect polyketide natural products with conjugated alkenes: Discovery of novodaryamide and nocarditriene. Acs Chemical Biology. 13:3097-3106.
    Abstract Summary:

    An optimized nitroso-based probe that facilitates the discovery of conjugated alkene-containing natural products in unprocessed extracts was developed. It chemoselectively reacts with conjugated olefins via a nitroso-Diels-Alder cyclization to yield derivatives with a distinct chromophore and an isotopically unique bromine atom that can be rapidly identified using liquid chromatography/mass spectrometry and a bioinformatics tool called...

  • Highlighted Publication
    Munch SB, Giron-Nava A., Sugihara G.  2018.  Nonlinear dynamics and noise in fisheries recruitment: A global meta-analysis. Fish and Fisheries. 19:964-973.
    Abstract Summary:

    The relative importance of environmental and intrinsic controls on recruitment in fishes has been studied for over a century. Despite this, we are not much closer to predicting recruitment. Rather, recent analyses suggest that recruitment is virtually independent of stock size and, instead, seems to occur in distinct environmental regimes. This issue of whether or not recruitment and subsequent production are coupled to stock size is highly...

  • Reimann S., Elkins JW, Fraser PJ, Hall BD, Kurylo M.J, Mahieu E., Montzka SA, Prinn RG, Rigby M, Simmonds PG et al..  2018.  Observing the atmospheric evolution of ozone-depleting substances. Comptes Rendus Geoscience. 350:384-392.
    Abstract Summary:

    The atmospheric observations of ozone-depleting substances (ODSs) have been essential for following their atmospheric response to the production and use restrictions imposed by the Montreal Protocol and its Amendments and Adjustments. ODSs have been used since the first half of the 20th century in industrial and domestic applications. However, their atmospheric growth went unnoticed until the early 1970s, when they were discovered using gas...

  • Kwon D., Sovers M.J, Grassian VH, Kleiber P.D, Young M.A.  2018.  Optical properties of humic material standards: Solution phase and aerosol measurements. 2:1102-1111.
    Abstract Summary:

    Aerosols generated from aqueous samples of readily obtainable humic material standards are often used as proxies for organic particulates found in the atmosphere in various investigations, such as consideration of radiative forcing effects. Here, we present results for the retrieved complex index of refraction, m = n + ik, at a wavelength of 403 nm for aerosols prepared from six humic material standards using a calibrated cavity ring-down...

  • Abstract Summary:

    UAComm (Underwater Acoustic Communication) is an active research area, and many experiment has been performed to develop UAComm system. In this paper, we investigate the possibility of modifying and applying VirTEX (Virtual Time series EXperiment) to medium long range MIMO (Multiple-Input Multiple-Output) UAComm of about 20 km range for the analysis and performance prediction of UAComm system. Since VirTEX is a time-domain simulator, the...

  • Abstract Summary:

    Hesionidae Grube, 1850 currently comprises over 175 species in 28 genera, placed in several subfamilies. Discoveries in recent years have largely been of deep-sea taxa. Here we describe a further four new hesionid species, mainly from methane cold seeps at around 1000-1800 m depths off the Pacific coast of Costa Rica and new record of another species. Several of these taxa also occur at methane seeps in the Guaymas Basis (Mexico) and off the...

  • Leiva C., Riesgo A., Avila C., Rouse GW, Taboada S..  2018.  Population structure and phylogenetic relationships of a new shallow-water Antarctic phyllodocid annelid. Zoologica Scripta. 47:714-726.
    Abstract Summary:

    Shallow-water polychaetes are abundant and diverse components of the Southern Ocean benthic communities, and although they have been widely studied, new species that are relatively common are still discovered. Here, we report the discovery of Pterocirrus giribeti sp. n., a new and abundant intertidal and upper-subtidal Antarctic phyllodocid. To establish the phylogenetic relationships of the new species, we sequenced two nuclear (18S and 28S...

  • Resplandy L., Keeling RF, Eddebbar Y., Brooks M.K, Wang R., Bopp L., Long M.C, Dunne J.P, Koeve W., Oschlies A..  2018.  Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition. Nature. 563:105-108.
    Abstract Summary:

    The ocean is the main source of thermal inertia in the climate system. During recent decades, ocean heat uptake has been quantified by using hydrographic temperature measurements and data from the Argo float program, which expanded its coverage after 2007. However, these estimates all use the same imperfect ocean dataset and share additional uncertainties resulting from sparse coverage, especially before 2007. Here we provide an independent...

  • Abstract Summary:

    The labrid fish Cirrhilabrus sanguineus Comic is redescribed on the basis of the neotype, two male specimens, and an additional female specimen recently collected from the northern coast of Mauritius. We provide new live and nuptial colouration descriptions, as well as the first documented female specimen for the species. we also include a molecular phylogenetic analysis of related species, with brief comments on phylogenetic interpretation...

  • Liu Q., Liu D., Bai J., Zhang Y.P, Zhou Y.D, Xu P.T, Liu Z.P, Chen S., Che H.C, Wu L. et al..  2018.  Relationship between the effective attenuation coefficient of spaceborne lidar signal and the IOPs of seawater. Optics Express. 26:30278-30291.
    Abstract Summary:

    Multiple scattering is an inevitable effect in spaceborne oceanic lidar because of the large footprint size and the high optical density of seawater. The effective attenuation coefficient klidar in the oceanic lidar equation, which indicates the influence of the multiple scattering effect on the formation of lidar returns, is an important parameter in the retrieval of inherent optical properties (IOPs) of seawater. In this paper, the...

  • Callaghan AH.  2018.  On the relationship between the energy dissipation rate of surface-breaking waves and oceanic whitecap coverage. Journal of Physical Oceanography. 48:2609-2626.
    Abstract Summary:

    Wave breaking is the most important mechanism that leads to the dissipation of oceanic surface wave energy. A relationship between the energy dissipation rate associated with breaking wave whitecaps and the area of whitecap foam per unit area ocean surface is expected, but there is a lack of consensus on what form this relationship should take. Here, mathematical representations of whitecap coverage in terms of are found to be linearly...

  • Levy M., Franks PJS, Smith K.S.  2018.  The role of submesoscale currents in structuring marine ecosystems. Nature Communications. 9
    Abstract Summary:

    From microbes to large predators, there is increasing evidence that marine life is shaped by short-lived submesoscales currents that are difficult to observe, model, and explain theoretically. Whether and how these intense three-dimensional currents structure the productivity and diversity of marine ecosystems is a subject of active debate. Our synthesis of observations and models suggests that the shallow penetration of submesoscale vertical...

  • Keen K.A, Thayre B.J, Hildebrand JA, Wiggins SM.  2018.  Seismic airgun sound propagation in Arctic Ocean waveguides. Deep-Sea Research Part I-Oceanographic Research Papers. 141:24-32.
    Abstract Summary:

    Underwater recordings of seismic airgun surveys in the deep-water Beaufort Sea and on the shallow-water Chukchi Sea shelf were made from sites on the continental slope and shelf break north-northwest of Point Barrow, Alaska. Airgun pulses from the deep-water survey were recorded more than 500 km away, and from the shallow-water survey up to similar to 100 km. In the deep-water, received sound pressure levels show spherical spreading...

  • Naughton P., Roux P, Schurgers C., Kastner R., Jaffe J.S, Roberts P.LD.  2018.  Self-localization of a mobile swarm using noise correlations with local sources of opportunity. Journal of the Acoustical Society of America. 144:2811-2823.
    Abstract Summary:

    Groups of coordinated underwater vehicles or sensors are powerful tools for monitoring the ocean. A requirement of many coordinated surveys is to determine a spatial reference between each node in a swarm. This work considers the self-localization of a swarm of independently moving vehicles using acoustic noise from a dominating incoherent source recorded by a single hydrophone onboard each vehicle. This method provides an inexpensive and...

  • Zhan P., Gopalakrishnan G, Subramanian AC, Guo D.Q, Hoteit I..  2018.  Sensitivity studies of the Red Sea eddies using adjoint method. Journal of Geophysical Research-Oceans. 123:8329-8345.
    Abstract Summary:

    Adjoint sensitivity analysis is applied to a set of eddies in the Red Sea using a high-resolution Massachusetts Institute of Technology general circulation model and its adjoint model. Previous studies have reported several eddy events in the Red Sea, namely, a dipole captured on 17 August 2001 in the southern Red Sea, a cyclonic eddy in November 2011 in the northern Red Sea, and an anticyclonic eddy in April 2010 in the central Red Sea....

  • Van Oostende N., Dussin R., Stock C.A, Barton A.D, Curchitser E., Dunne J.P, Ward B.B.  2018.  Simulating the ocean's chlorophyll dynamic range from coastal upwelling to oligotrophy. Progress in Oceanography. 168:232-247.
    Abstract Summary:

    The measured concentration of chlorophyll a in the surface ocean spans four orders of magnitude, from similar to 0.01 mg m(-3) in the oligotrophic gyres to > 10 mg m(-3) in coastal zones. Productive regions encompass only a small fraction of the global ocean area yet they contribute disproportionately to marine resources and biogeo-chemical processes, such as fish catch and coastal hypoxia. These regions and/or the full observed range of...

  • Young AP, Flick RE, Gallien TW, Giddings SN, Guza RT, Harvey M., Lenain L, Ludka B.C, W. Melville K, O'Reilly W.C.  2018.  Southern California coastal response to the 2015–2016 El Niño. Journal of Geophysical Research: Earth Surface. 123:3069-3083.
    Abstract Summary:

    Widespread erosion associated with energetic waves of the strong 2015–2016 El Niño on the U.S. West Coast has been reported widely. However, Southern California was often sheltered from the northerly approach direction of the offshore waves. The few large swells that reached Southern California were not synchronous with the highest tides. Although west coast-wide tidal anomalies were relatively large in 2015–2016, in Southern California,...

  • Nannuru S, Koochakzadeh A, Gemba KL, Pal P, Gerstoft P.  2018.  Sparse Bayesian learning for beamforming using sparse linear arrays. The Journal of the Acoustical Society of America. 144:2719-2729.
    Abstract Summary:

    Sparse linear arrays such as co-prime and nested arrays can resolve more sources than the number of sensors. In contrast, uniform linear arrays (ULA) cannot resolve more sources than the number of sensors. This paper demonstrates this using Sparse Bayesian learning (SBL) and co-array MUSIC for single frequency beamforming. For approximately the same number of sensors, co-prime and nested arrays are shown to outperform ULA in root mean squared...

  • Luca E., Smith SGL.  2018.  Stokes flow through a two-dimensional channel with a linear expansion. Quarterly Journal of Mechanics and Applied Mathematics. 71:441-462.
    Abstract Summary:

    Motivated by various applications in microfluidics, we consider low-Reynolds-number flow in a two-dimensional channel with different widths in the upstream and downstream directions. The channel geometry consists of a polygonal domain with angled edges at transition points. The polygonal nature of the geometry makes it amenable to analysis via the Unified Transform Method, providing quasi-analytical solutions which can be used to compute all...

  • Abstract Summary:

    The analysis of volatiles released by marine Salinispora bacteria uncovered a new class of natural compounds displaying an unusual bicyclic [3.1.0]-lactone skeleton. Although only sub-mu g quantities of the compounds were available, the combination of analytical methods, computational spectroscopy, and synthesis allowed unambiguous structural identification of the compounds, called salinilactones, without the need for isolation. Orthogonal...

  • Betts R.A, Jones CD, Knight J.R, Keeling RF, Kennedy J.J, Wiltshire A.J, Andrew R.M, Aragao L.  2018.  A successful prediction of the record CO2 rise associated with the 2015/2016 El Nino. Philosophical Transactions of the Royal Society B-Biological Sciences. 373
    Abstract Summary:

    In early 2016, we predicted that the annual rise in carbon dioxide concentration at Mauna Loa would be the largest on record. Our forecast used a statistical relationship between observed and forecast sea surface temperatures in the Nino 3.4 region and the annual CO2 rise. Here, we provide a formal verification of that forecast. The observed rise of 3.4 ppm relative to 2015 was within the forecast range of 3.15 +/- 0.53 ppm, so the prediction...

  • Ramsay R., Di Marco C.F, Heal M.R, Twigg M.M, Cowan N., Jones M.R, Leeson S.R, Bloss W.J, Kramer L.J, Crilley L. et al..  2018.  Surface-atmosphere exchange of inorganic water-soluble gases and associated ions in bulk aerosol above agricultural grassland pre- and postfertilisation. Atmospheric Chemistry and Physics. 18:16953-16978.
    Abstract Summary:

    The increasing use of intensive agricultural practices can lead to damaging consequences for the atmosphere through enhanced emissions of air pollutants. However, there are few direct measurements of the surface-atmosphere exchange of trace gases and water-soluble aerosols over agricultural grassland, particularly of reactive nitrogen compounds. In this study, we present measurements of the concentrations, fluxes and deposition velocities of...

  • Abstract Summary:

    Water column bulk Pseudo-nitzschia abundance and the dissolved and particulate domoic acid (DA) concentrations were measured in the Santa Barbara Basin (SBB), California from 2009-2013 and compared to bulk Pseudo-nitzschia cell abundance and DA concentrations and fluxes in sediment traps moored at 147 m and 509 m. Pseudo-nitzschia abundance throughout the study period was spatially and temporally heterogeneous (<200 cells L-1 to 3.8 x 10(6...

  • Healy T.M, Brennan R.S, Whitehead A., Schulte P.M.  2018.  Tolerance traits related to climate change resilience are independent and polygenic. Global Change Biology. 24:5348-5360.
    Abstract Summary:

    The resilience of organisms to climate change through adaptive evolution is dependent on the extent of genetically based variation in key phenotypic traits and the nature of genetic associations between them. For aquatic animals, upper thermal tolerance and hypoxia tolerance are likely to be a important determinants of sensitivity to climate change. To determine the genetic basis of these traits and to detect associations between them, we...

  • Fan W.Y, de Groot-Hedlin C.D, Hedlin MAH, Ma Z.T.  2018.  Using surface waves recorded by a large mesh of three-element arrays to detect and locate disparate seismic sources. Geophysical Journal International. 215:942-958.
    Abstract Summary:

    Surface waves recorded by global arrays have proven useful for locating tectonic earthquakes and in detecting slip events depleted in high frequency, such as glacial quakes. We develop a novel method using an aggregation of small-to continental-scale arrays to detect and locate seismic sources with Rayleigh waves at 20-50 s period. The proposed method is a hybrid approach including first dividing a large aperture aggregate array into Delaunay...

  • Rogowski P, de Paolo T., Terrill E, McNinch J..  2018.  X-band radar mapping of morphological changes at a dynamic coastal inlet. Journal of Geophysical Research-Earth Surface. 123:3034-3054.
    Abstract Summary:

    Remote sensing of the complex interactions between bathymetry, tidal flow, and waves in coastal inlets provides high-resolution data sets that can be exploited to characterize the morphological variability of shallow ebb tidal deltas (ETD). Here we used observations from a mobile X-band radar platform to determine optimal conditions during which radar-derived shoal signatures best represent positions of underlying shoals. Significant...

  • Udry A., Day JMD.  2018.  1.34 billion-year-old magmatism on Mars evaluated from the co-genetic nakhlite and chassignite meteorites. Geochimica Et Cosmochimica Acta. 238:292-315.
    Abstract Summary:

    Nakhlite and chassignite martian meteorites have similar crystallization (1340 +/- 40 Ma) and ejection (similar to 11 Ma) ages, and Rb-87-Sr-87 and (143)sm-Nd-144 compositions. Using a near-comprehensive suite of these rocks, we place further constraints on nakhlite and chassignite petrogenesis, utilizing bulk rock and mineral major- and trace-element compositions, and quantitative textural data for 17 samples, including three recent finds (...

  • Pham H.T, Sarkar S..  2018.  Ageostrophic secondary circulation at a submesoscale front and the formation of gravity currents. Journal of Physical Oceanography. 48:2507-2529.
    Abstract Summary:

    Large-eddy simulations are performed to investigate the development of the ageostrophic secondary circulation (ASC) and associated transport in a submesoscale front. Based on the observations in the northern Bay of Bengal and in the Pacific cold tongue, the model front has a large cross-front density difference that is partially compensated with lateral temperature and salinity gradients. Vertical stratification is varied in different cases...