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Carbon emissions and their ocean impactsAnthropogenic CO2 emissions directly affect atmospheric chemistry but also have a strong influence on the oceans. Gattuso et al. review how the physics, chemistry, and ecology of the oceans might be affected based on two CO2 emission trajectories: one business as usual and one with aggressive reductions. Ocean warming, acidification, sea-level rise, and the expansion of oxygen minimum zones will continue to have distinct impacts on marine communities and ecosystems. The path that humanity takes regarding CO2 emissions will largely determine the severity of these phenomena.Science, this issue 10.1126/science.aac4722 The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems-and the goods and services they provide-for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario-consistent with the Copenhagen Accord's goal of a global temperature increase of less than 2 degree C-is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies. Consequently, any new climate regime that fails to minimize ocean impacts would be incomplete and inadequate.

The University of York's laser-induced fluorescence (LIF) instrument for measuring sulfur dioxide (SO2) was compared to a commercial pulsed fluorescence (PF) analyser and iodide chemical ionisation mass spectrometer (I−CIMS) aboard the UK FAAM research aircraft in both remote and ship-polluted marine environments. In high SO2 concentration plumes, the LIF instrument and PF analyser compared well, but LIF was the only instrument capable of SO2 measurements in the remote marine boundary layer due to its campaign limit of detection (LoD, 3σ) of 0.07 ppb at 10 s compared with 0.4 ppb for the PF analyser. Quantification of SO2 using I−CIMS was challenging due to a significant interference, but good signal correlation with the other instruments was observed in polluted air masses. A comparison of response time was also made, for which the I−CIMS and LIF instrument proved much faster than the PF analyser with 3 e-folding times of 0.6, 2 and 17 s respectively. This work demonstrates the importance of sensitive instrumentation like the LIF system for quantifying low concentrations of SO2, such as over remote marine environments, at the time resolutions required for a fast moving platform. This is particularly relevant now as a result of more stringent sulfur emission regulations for shipping, and likely more so in the future as anthropogenic SO2 concentrations continue to decline.

[This corrects the article DOI: 10.1371/journal.pone.0175341.].

We present a method to construct and analyse 3D models of underwater scenes using a single cost-effective camera on a standard laptop with (a) free or low-cost software, (b) no computer programming ability, and (c) minimal man hours for both filming and analysis. This study focuses on four key structural complexity metrics: point-to-point distances, linear rugosity (R), fractal dimension (D), and vector dispersion (1/k). We present the first assessment of accuracy and precision of structure-from-motion (SfM) 3D models from an uncalibrated GoPro™ camera at a small scale (4 m2) and show that they can provide meaningful, ecologically relevant results. Models had root mean square errors of 1.48 cm in X-Y and 1.35 in Z, and accuracies of 86.8% (R), 99.6% (D at scales 30-60 cm), 93.6% (D at scales 1-5 cm), and 86.9 (1/k). Values of R were compared to in-situ chain-and-tape measurements, while values of D and 1/k were compared with ground truths from 3D printed objects modelled underwater. All metrics varied less than 3% between independently rendered models. We thereby improve and rigorously validate a tool for ecologists to non-invasively quantify coral reef structural complexity with a variety of multi-scale metrics.

During the first part of the Martian year (Ls = 50°–160°) a phenomenon occurs on Mars in the tropical and equatorial regions (30°N–10°S) known as the Aphelion Cloud Belt (ACB). During this time, there is prominent formation and diurnal variability of water ice clouds. Limited empirical attempts have been made to characterize the magnitude of radiative flux contributions from clouds to nighttime surface temperatures. In this work, we estimated the infrared (IR) flux contribution at ground level from the clouds by comparing surface temperature data from the Thermal Emission Spectrometer (TES) onboard Mars Global Surveyor (MGS) to calculated temperatures using the KRC numerical thermal model. We then generated a database of IR fluxes at the ground contributed by clouds spanning the entirety of the tropical and equatorial regions as a function of Solar Longitude (Ls) on Mars in one degree bins. We compared results with work presented elsewhere in the literature and found good agreement. We also found that temporal trends followed the general established range for the ACB but our analysis demonstrated the peak ACB values occurred at later times (Ls = 100°–140°) than previously published data sets using water ice opacity retrievals (Ls = 90°–110°). This database may be used in comparison to calculated Global Climate Model fluxes as well as a lookup tool for more precise estimation of surface and subsurface thermal environments in these regions. Plain Language Summary Previous work has shown that during the spring and summer seasons of the Martian northern hemisphere bands of water ice clouds form in the tropical and equatorial regions of Mars. These clouds tend to persist into the night and they have the capability of warming the surfaces below. Quantifying this warming is important for isolating the thermal and physical characteristics of Martian surface and subsurface materials. In the past, climate models have been used to understand the contribution of surface warming from these clouds but no attempt has been made to derive these contributions using data. In this study we used data from the Mars Global Surveyor Thermal Emission Spectrometer instrument, coupled with a thermal model, to derive the warming contributions from these clouds. We generated a database of these derived contributions which can be used to better describe the surface and subsurface of Mars in the equatorial and tropical regions as well as to be used as a comparative tool for climate models. Key Points We developed a methodology to derive radiative contributions of nighttime cloud fluxes on Mars using orbitally retrieved data and a thermal model Our results show general seasonal and spatial agreement with cloud opacity data sets published in the literature We found that these data sets may be used to describe surface thermophysical properties with better accuracy

The phylogeny of the superfamily Chirostyloidea (Decapoda: Anomura) has been poorly understood owing to limited taxon sampling and discordance between different genes. We present a nine-gene dataset across 15 chirostyloids, including all known yeti crabs (Kiwaidae), to improve the resolution of phylogenetic affinities within and between the different families, and to date key divergences using fossil calibrations. This study supports the monophyly of Chirostyloidea and, within this, a basal split between Eumunididae and a Kiwaidae–Chirostylidae clade. All three families originated in the Mid-Cretaceous, but extant kiwaids and most chirostylids radiated from the Eocene onwards. Within Kiwaidae, the basal split between the seep-endemic Kiwa puravida and a vent clade comprising Kiwa hirsuta and Kiwa spp. found on the East Scotia and Southwest Indian ridges is compatible with a hypothesized seep-to-vent evolutionary trajectory. A divergence date estimate of 13.4–25.9 Ma between the Pacific and non-Pacific lineages is consistent with Kiwaidae spreading into the Atlantic sector of the Southern Ocean via the newly opened Drake Passage. The recent radiation of Kiwaidae adds to the list of chemosynthetic fauna that appear to have diversified after the Palaeocene/Eocene Thermal Maximum, a period of possibly widespread anoxia/dysoxia in deep-sea basins.

Compositional mapping of Mars at the 100-metre scale with the Mars Odyssey Thermal Emission Imaging System (THEMIS) has revealed a wide diversity of igneous materials. Volcanic evolution produced compositions from low-silica basalts to high-silica dacite in the Syrtis Major caldera. The existence of dacite demonstrates that highly evolved lavas have been produced, at least locally, by magma evolution through fractional crystallization. Olivine basalts are observed on crater floors and in layers exposed in canyon walls up to 4.5 km beneath the surface. This vertical distribution suggests that olivine-rich lavas were emplaced at various times throughout the formation of the upper crust, with their growing inventory suggesting that such ultramafic (picritic) basalts may be relatively common. Quartz-bearing granitoid rocks have also been discovered, demonstrating that extreme differentiation has occurred. These observations show that the martian crust, while dominated by basalt, contains a diversity of igneous materials whose range in composition from picritic basalts to granitoids rivals that found on the Earth. Martian minerals mapped Infrared measurements from the orbiting Mars Odyssey probe have been used to produce the most detailed map yet of mineral distribution on the martian surface. The rocks show a surprisingly complex volcanic history. Lavas range from primitive mantle-derived basalts to silica-rich rocks that probably formed in magma chambers following the re-melting of previously erupted rocks. Also present are volcanic basalts that contain more than 20% olivine, a mineral that is quickly weathered by water. Similar olivine-rich rocks were found in eroded canyon walls and ancient crater floors that date back billions of years. This suggests that during each period of olivine layer deposition, Mars did not have extensive water on its surface.

Planetary analog simulations are a powerful exercise for understanding the utility of deployable instruments, their operational protocols, and the visualization of data products during ExtraVehicular Activities (EVAs). This paper presents results of a field campaign by the NASA Solar System Exploration Research Virtual Institute (SSERVI) Remote, In Situ and Synchrotron Studies for Science and Exploration‐2 (RISE2) team to Kilbourne Hole, New Mexico in March/April 2023 to test the utility of a portable thermal infrared (TIR) hyperspectral imager (HSI) during four EVA simulations. The HSI provides emitted radiance spectra from 7 to 14 μm to map spectral variations likely caused by composition and physical properties, which allows HSI data products to aid in sample selection and site documentation. Four pairs of analog astronauts performed a mock EVA at three stations with field deployable instruments including an HSI. The HSI was found to be a useful tool for performing reconnaissance observations, field site documentation, and sample selection for visibly indistinct materials. From these analog simulations we prioritize two recommendations for use of HSI's in crewed missions. First, HSI‐derived data products should be tailored for the specific science objectives and/or sampling objectives of the mission to expedite interpretation and decision‐making. Second, the HSI instrument would ideally have a wide field‐of‐view/panoramic capability to reduce crew time selecting sites to image. Additionally, pre‐EVA reconnaissance from a remotely operated rover could be conducted with an HSI to collect data prior to disturbance and again post human activity. Plain Language Summary Testing instruments in scenarios similar to how they would be used by astronauts on the Moon is important for developing useful data products and operational protocols. One such instrument that was tested is a portable thermal infrared hyperspectral imager (HSI) that provides information regarding the diversity of targets within an image. In a field test, we simulated how images from the HSI would be used to identify samples to collect and bring back to a laboratory for further detailed studies. Our field test revealed that the HSI is a useful tool for identifying unique and site representative samples, for planning which samples to collect, and for documentation of spectral (i.e., compositional information) characteristics of the site. Some recommendations that came from the field test include (a) tailoring the data products for the specific science to be addressed and samples collected, and (b) the HSI instrument should have a wide field‐of‐view/panoramic capability to reduce crew mental load. Additionally, the utilization of an HSI prior to human activity via remote operations could potentially enhance the science return of an HSI. Key Points Hyperspectral imagers aid in reconnaissance and detection of visibly indistinct materials (i.e., volatiles) Hyperspectral imaging instruments and their data products should be adaptable to various scientific and operational needs Recommendations include data products tailored to science objectives and expanded FOV capabilities to reduce the mental load on crew

Marine nematodes, which play an important role in many ecosystems, include a number of apparently cosmopolitan taxa that exhibit broad biogeographic ranges even though there is no obvious dispersal phase in their lifecycle. In this study, standard taxonomic approaches to marine nematode identification in conjunction with multivariate statistical analysis of morphometric data were compared with molecular techniques. Specimens of the marine nematode Terschellingia longicaudata that had been identified by their morphological features were investigated from a range of localities (East and West Atlantic, Bahrain, Malaysia) and habitats (estuarine, intertidal, subtidal) using molecular approaches based on the amplification and sequencing of the small subunit ribosomal RNA (18S rRNA). The study revealed that the majority of the morphologically defined T. longicaudata specimens share a single 18S rRNA sequence and apparently belong to a single taxon distributed from the British Isles to Malaysia. In addition, 18S rRNA analysis also revealed two additional sequences. One of these sequences was found in both the British Isles and Mexico, the other was recorded only from British waters. Individuals collected in Bahrain and identified from their morphology as T. longicaudata had two highly divergent 18S rRNA sequences. Separate morphological and morphometric approaches to identification of specimens from the same sites that had been formalin-preserved did not support evidence of multiple genotypes revealed previously by molecular analysis. Current taxonomy based on morphological characters detected using light-microscopy may be unable to discriminate possible species complexes. Biodiversity of marine nematodes may often be underestimated due to the presence of morphologically cryptic species complexes. High-throughput techniques such as DNA barcoding would aid in species identification but may require thorough analysis of multiple nuclear and mitochondrial molecular markers.

Instruments that yield information about the mineralogy and chemistry of surface materials will be part of future robotic and human exploration of the Moon and Mars. Accurate interpretation of such data can be informed by coordinated analyses of relevant materials in terrestrial analog terrains. We used a suite of portable instrumentation—visible-to-shortwave infrared (VSWIR) spectroscopy, thermal infrared (TIR) spectroscopy, and X-ray fluorescence—to conduct coordinated mineralogical, geochemical, and visual characterization of a suite of outcrops and loose rocks in Kilbourne Hole and Hunts Hole, New Mexico. A variety of textures, particle sizes, and petrogenetic origins were examined. Data were interpreted using spectral models, spectral library comparisons, and chemical calibration curves and compared to mineralogical information derived from X-ray diffraction. Insights and limitations for each technique are presented in terms of surface type; for example, both the VSWIR and TIR instruments exhibited limitations in discerning the full mineralogy of the fine-grained tuff beds. The diverse suite of xenoliths was apparent in TIR spectral images, and the dominant mineral component was identifiable through linear unmixing of TIR spectra. However, inaccuracies in mineral abundance were also observed, highlighting the need for use of more advanced analysis methods. Known lithological diversity was less apparent in VSWIR spectra, which were dominated by minor amounts of phyllosilicates within or coating the rocks. Finally, based on the dearth of mafic minerals and the abundance of quartz, we infer that the Kilbourne/Hunts tuff beds are dominated by fragments of country rock (“accidentals”) rather than juvenile magmatic materials.