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Reef communities at intermediate (10 to 30 m) and mesophotic (~ 30 to 150 m) depths occupy large areas of sea floor but little is known about their potential to accrete vertically, their response to sea-level change and other environmental perturbations. In this study, the authors have examined cores from two holes, M0040A and M0041A, drilled by the International Ocean Drilling Program Expedition 325 along the shelf edge of the modern GBR at 131 m water depth. The objective was to investigate reef growth history at palaeo-water depths > 20 m over a time period spanning 30,000 years, from the end of the Last Glacial period through the last deglaciation. Based on changes in lithologies and biotic components, and a robust chronostratigraphic framework supported by 47 radiometric ages, the authors have identified two episodes of reef growth, one during Marine Isotope Stage (MIS) 2 and the other at the onset of the deglaciation, both characterised by abundant microbialite crusts and distinct coral assemblages. Palaeo-water depths range from 30 to 60 m and from 20 to 30 m for the MIS 2 and early deglacial reef sections, respectively. The first episode of reef growth documented in the cores initiated at 27 to 25 ka, possibly in response to increased light availability and change in sedimentation resulting from falling sea-level between 32 and 29 ka from MIS 3 and also to low atmospheric pCO2 at the end of the Last Glacial period. Reef accretion was reduced or ceased sometime between 24 and 19 ka, coinciding with the rapid 20 m sea-level fall of the peak Last Glacial Maximum and minima of SSTs. Reef growth resumed at 19.5 to 18.5 ka, influenced by a period of moderate sea-level rise and increasing sea surface temperatures at the onset of the deglaciation. Reef growth termination at ca. 17 ka correlates with a major episode of reef demise previously identified in adjacent mid and outer terrace cores and linked to reduced water quality combined with rapid deglacial sea-level rise. Vertical accretion (VA) rates were calculated based on two methods: linear visual fitting and Bayesian modelling. The findings show that the highest VA rates are associated with microbialite boundstone. Reef ecosystems dominated by microbialite and corals developed at intermediate and mesophotic depths, and grew vertically at maximum rates of 2 to 5 mm yr-1 depending on the method used, over a period of rapid environmental change during the transition from MIS 3 to MIS 1. Further study needs to explore the potential of modern-type deep coralgal communities to cope with higher rates of sea-level rise predicted this century.

In 1980, the law creating Small Business Development Centers (SBDCs) was enacted. As part of the law, funding for local SBDCs comes from both the Small Business Administration (SBA) and a host institution such as a university and/or community college. The relationship between the host institution and the SBDC is not well defined except through the financial commitment. This research was an exploratory investigation to determine the extent in which SBDCs interact, if any, with their host institution. An open-ended survey was designed and distributed to over 600 SBDC Advisors as listed in America’s Small Business Development Centers’ (ASBDC) contact list. A total of 57 surveys were completed by the respondents. This research presents the summary of these questions as to the type of interaction, which students, and what activities these advisors had with the students of their host institution.

The Great Barrier Reef (GBR) is an internationally recognized and widely studied ecosystem, yet little is known about its sea surface temperature evolution since the Last Glacial Maximum (LGM) (~20 kyr BP). Here, we present the first paleo‐application of Isopora coral‐derived SST calibrations to a suite of 25 previously published fossil Isopora from the central GBR spanning ~25‐11 kyr BP. The resultant multi‐coral Sr/Ca‐ and δ18O‐derived sea surface temperature anomaly (SSTA) histories are placed within the context of published relative sea level, reef sequence and coralgal reef assemblage evolution. Our new calculations indicate SSTs were cooler on average by ~5‐5.5°C at Noggin Pass (~17°S) and ~7‐8°C at Hydrographer's Passage (~20°S) (Sr/Ca‐derived) during the LGM, in line with previous estimates (Felis et al., 2014). We focus on contextualizing the Younger Dryas Chronozone (YDC, ~12.9‐11.7 kyr BP), whose southern hemisphere expression, in particular in Australia, is elusive and poorly constrained. Our record does not indicate cooling during the YDC with near modern temperatures reached during this interval on the GBR, supporting an asymmetric hemispheric presentation of this climate event. Building on a previous study (Felis et al., 2014), these fossil Isopora SSTA data from the GBR provide new insights into the deglacial reef response, with near‐modern warming during the YDC, since the LGM.

International audience; Previous drilling through submerged fossil coral reefs has greatly improved our understanding of the general pattern of sea-level change since the Last Glacial Maximum, however, how reefs responded to these changes remains uncertain. Here we document the evolution of the Great Barrier Reef (GBR), the world’s largest reef system, to major, abrupt environmental changes over the past 30 thousand years based on comprehensive sedimentological, biological and geochronological records from fossil reef cores. We show that reefs migrated seaward as sea level fell to its lowest level during the most recent glaciation (~20.5–20.7 thousand years ago (ka)), then landward as the shelf flooded and ocean temperatures increased during the subsequent deglacial period (~20–10 ka). Growth was interrupted by five reef-death events caused by subaerial exposure or sea-level rise outpacing reef growth. Around 10 ka, the reef drowned as the sea level continued to rise, flooding more of the shelf and causing a higher sediment flux. The GBR’s capacity for rapid lateral migration at rates of 0.2–1.5 m yr$^{−1}$ (and the ability to recruit locally) suggest that, as an ecosystem, the GBR has been more resilient to past sea-level and temperature fluctuations than previously thought, but it has been highly sensitive to increased sediment input over centennial–millennial timescales.

Introducing a new cat into a household with one or more resident cats can be a significant source of stress for the cats involved. These studies sought to determine if rabbit maternal-neonatal pheromone (2-methyl-2-butenal [2M2B]) in litter impacted cat social behaviors and litter box use. Study 1 determined that cats preferred to eliminate in litter containing 2M2B; other semiochemicals tested did not change litter box use. Cats prone to aggression were identified in an intermediate pilot study, and eight pairs of these cats were selected for Study 2. In Study 2, cat pairs were provided litter containing either vehicle or 2M2B for 24 hours. Cats experiencing control litter displayed more aggression during the first 6 hours (p

The approximately 10,000-year-long Last Glacial Maximum, before the termination of the last ice age, was the coldest period in Earth’s recent climate history1. Relative to the Holocene epoch, atmospheric carbon dioxide was about 100 parts per million lower and tropical sea surface temperatures were about 3 to 5 degrees Celsius lower2,3. The Last Glacial Maximum began when global mean sea level (GMSL) abruptly dropped by about 40 metres around 31,000 years ago4 and was followed by about 10,000 years of rapid deglaciation into the Holocene1. The masses of the melting polar ice sheets and the change in ocean volume, and hence in GMSL, are primary constraints for climate models constructed to describe the transition between the Last Glacial Maximum and the Holocene, and future changes; but the rate, timing and magnitude of this transition remain uncertain. Here we show that sea level at the shelf edge of the Great Barrier Reef dropped by around 20 metres between 21,900 and 20,500 years ago, to −118 metres relative to the modern level. Our findings are based on recovered and radiometrically dated fossil corals and coralline algae assemblages, and represent relative sea level at the Great Barrier Reef, rather than GMSL. Subsequently, relative sea level rose at a rate of about 3.5 millimetres per year for around 4,000 years. The rise is consistent with the warming previously observed at 19,000 years ago1,5, but we now show that it occurred just after the 20-metre drop in relative sea level and the related increase in global ice volumes. The detailed structure of our record is robust because the Great Barrier Reef is remote from former ice sheets and tectonic activity. Relative sea level can be influenced by Earth’s response to regional changes in ice and water loadings and may differ greatly from GMSL. Consequently, we used glacio-isostatic models to derive GMSL, and find that the Last Glacial Maximum culminated 20,500 years ago in a GMSL low of about −125 to −130 metres. © 2018, Macmillan Publishers Ltd., part of Springer Nature. Japan Society for the Promotion of Science-JP16H06309,JP17H01168,JP26247085,JP15KK0151 Australian Research Council-DP1094001 National Eye Research Centre-NE/H014136/1 Institut National Polytechnique de Toulouse

The approximately 10,000-year-long Last Glacial Maximum, before the termination of the last ice age, was the coldest period in Earth's recent climate history

Caribbean coastal ecosystems have undergone severe degradation both historically and recently, primarily caused by the synergistic effects of overfishing, eutrophication, sedimentation, disease, and other factors associated with humans. Baseline conditions from pristine Caribbean reefs and seagrass beds are required to understand and quantify degradation. Only the fossil record can provide pre-human baselines. We present preliminary results from a recently discovered mid-Holocene (7.2-5.7 ka) fossil fringing reef and seagrass system in Bocas del Toro, Panama. Molluscan assemblages from the fossil reef and seagrass habitats were compared to death assemblages in corresponding modern habitats. The proportion of suspension-feeding molluscs more than doubled from fossil to the present day in the reef habitat, and the proportion of herbivores declined by a third, reflecting declines in coral cover and architecture, and increased eutrophy. Conversely, in seagrass beds, the proportion of different mollusc guilds was remarkably similar between fossil and modern day, suggesting that unlike reefs, seagrass beds are functionally similar today compared to a "pristine" baseline, although key community members were different. Our study reveals novel evidence that the health of molluscan communities on Caribbean reefs may have declined to the extent observed in corals and fish, and that the decline follows a trajectory predicted by known ecosystem degradation. Molluscs represent a biodiverse and functionally crucial component of reefs and must be considered in ecosystem-scale research on reef conservation. Revealing the structure of baseline communities using the fossil record represents one important step toward this aim.

Tropical south-western Pacific temperatures are of vital importance to the Great Barrier Reef (GBR), but the role of sea surface temperatures (SSTs) in the growth of the GBR since the Last Glacial Maximum remains largely unknown. Here we present records of Sr/Ca and δ(18)O for Last Glacial Maximum and deglacial corals that show a considerably steeper meridional SST gradient than the present day in the central GBR. We find a 1-2 °C larger temperature decrease between 17° and 20°S about 20,000 to 13,000 years ago. The result is best explained by the northward expansion of cooler subtropical waters due to a weakening of the South Pacific gyre and East Australian Current. Our findings indicate that the GBR experienced substantial meridional temperature change during the last deglaciation, and serve to explain anomalous deglacial drying of northeastern Australia. Overall, the GBR developed through significant SST change and may be more resilient than previously thought.

Whether sea level was stable during the last interglacial remains a subject of debate. An analysis of the U–Th ages of coral reefs in the Bahamas, corrected for open-system behaviour, confirms the presence of at least one oscillation within the sea-level highstand.

As this article is published, the U.S. Census Bureau is completing work for the twenty third decennial census of the United States. Once again, the MAF/TIGER system served as the geospatial infrastructure supporting numerous census operations and data collection, tabulation, and dissemination activities. From data collection to data dissemination we trace the recent activities of the 2010 Decennial Census of the United States to illustrate the role maps and geospatial data play in an increasing variety of public and private sector activities across the nation. To ensure a successful 2010 Census, millions of maps had to be created. This article will give an overview of the automated mapping system designed to create these maps. This includes a discussion about associated software needed and the variety of map types that were developed. Finally, future map production and geospatial activities at the Census Bureau will be discussed.

In order to create a useful map, the cartographer must select a scale at which the map reader can distinguish features shown on the map and read their labels. However, the choice of scale for a paper map is also constrained by the size of the map sheet and by the cost of working with a large number of sheets. When the feature density pattern allows, space can be conserved by making the map at more than one scale: a small scale suitable for most of the map, while dense features are shown on inset maps at larger scales. Creating inset maps requires the cartographer to make a series of complex, interrelated decisions regarding the most effective overall sheet configuration, which is dependent upon the scale chosen for the main map and how the inset maps are created. The Census Automated Map Production System (CAMPS) applies cartographic logic and density analysis to make these decisions in a fully automated mapping environment.

The astronomical theory of climate change asserts that Earth's climate is affected by changes in its orbit, which vary the seasonal and latitudinal distribution of solar radiation. This theory is the basis of the orbitally tuned SPECMAP timescale. A key constraint for this important chronology was the mid-point of the Penultimate Deglaciation, initially dated to 127,000 years ago. Recent work suggests this event may be considerably older, casting doubt on the astronomical theory, the SPECMAP timescale, and the accuracy of orbitally tuned chronologies. Difficulties with U/Th coral dating of sea-level events have impeded progress on this problem, because most corals are not closed systems. Here, we use a new approach to U/Th dating that corrects for open-system behavior and produces a sea-level curve of sufficient resolution to confidently correlate with SPECMAP over the last 240,000 years, permitting a reassessment of both this critical chronology and a central tenet of climate change theory. High-precision ages for 24 oxygen isotope events provide a 240,000-year chronology for marine δ18O records that is independent of orbital tuning assumptions. Although there appear to be significant differences between the radiometric and orbitally tuned timescales near the lastglacial maximum and at the Marine Isotope Stage 7/6 boundary, a comparison of radiometric and SPECMAP ages for identical isotope events suggest that the SPECMAP timescale is quite accurate and that its errors were, in general, overestimated. Despite suborbital complexity, orbital cyclicity is clearly evident in our record. High-amplitude sea-level oscillations at periods greater than ∼20,000 years are very close in phase to summer insolation in the Northern Hemisphere. Although sea-level changes cannot be uniquely tied to a specific season or latitude of insolation forcing, the simplest explanation is that long-period, high-amplitude sea-level change is linked to Northern Hemisphere insolation forcing. These results validate the principles of orbital tuning and suggest such timescales are generally robust.

Sea level is a sensitive index of global climate that has been linked to Earth's orbital variations, with a minimum periodicity of about 21,000 years. Although there is ample evidence for climate oscillations that are too frequent to be explained by orbital forcing, suborbital-frequency sea-level change has been difficult to resolve, primarily because of problems with uranium/thorium coral dating. Here we use a new approach that corrects coral ages for the frequently observed open-system behavior of uranium-series nuclides, substantially improving the resolution of sea-level reconstruction. This curve reveals persistent sea-level oscillations that are too frequent to be explained exclusively by orbital forcing.

The source of excess 234U in fossil corals and its relationship to U-series age determinations has been an outstanding problem in geochronology for more than 20 years. With increasing numbers of U-series isotope measurements in corals, and significant improvements in analytical precision through mass spectrometry, it is increasingly apparent that a substantial fraction of observed isotope ratios cannot be reasonably explained by closed-system decay. Moreover, observations of a positive correlation between 234U/238U and 230Th/238U ratios in corals from the same terrace are difficult to explain. However, the decay of dissolved uranium and α-recoil mobilization of uranium daughters produce particle-reactive 234Th and 230Th, and the coupled addition of these Th isotopes could simultaneously increase coral 234U/238U and 230Th/238U. Here we present a quantitative model, based on decay-dependent redistribution of 234Th and 230Th, permitting calculation of open-system coral ages. These equations provide a general solution to the α-recoil redistribution problem, applicable to any alpha decay series. While measured isotope ratios of corals from the three youngest stratigraphically defined Barbados terraces are inconsistent with closed-system decay, they fall in broadly linear arrays agreeing with model predictions. Isotopic arrays of older Barbados corals, and corals from terraces around the world, are also consistent with model predictions suggesting the open-system model is generally applicable. Corals with extreme isotopic compositions that are impossible to produce by closed-system decay are consistent with the limited range of isotopic compositions predicted by the model at ages older than 600 ka. For corals from a single terrace, 234Th and 230Th redistribution appears to be a source of systematic conventional age error, even for corals with slightly elevated 234U. However, open-system ages are consistent, even for corals with extremely elevated 234U. For the youngest three Barbados terraces, mean open-system terrace ages are consistent with mean conventional terrace ages calculated from pristine samples. If the most accurate conventional ages are from corals with an initial 234U/238U identical to modern seawater, then the open-system model will improve the accuracy of coral U-series age determinations and dramatically increase the number of reliable ages.

Tropical south-western Pacific temperatures are of vital importance to the Great Barrier Reef (GBR), but the role of sea surface temperatures (SSTs) in the growth of the GBR since the Last Glacial Maximum remains largely unknown. Here we present records of Sr/Ca and δ18O for Last Glacial Maximum and deglacial corals that show a considerably steeper meridional SST gradient than the present day in the central GBR. We find a 1–2 °C larger temperature decrease between 17° and 20°S about 20,000 to 13,000 years ago. The result is best explained by the northward expansion of cooler subtropical waters due to a weakening of the South Pacific gyre and East Australian Current. Our findings indicate that the GBR experienced substantial meridional temperature change during the last deglaciation, and serve to explain anomalous deglacial drying of northeastern Australia. Overall, the GBR developed through significant SST change and may be more resilient than previously thought., The Great Barrier Reef (GBR) is under threat from rising ocean temperatures, yet its response to past temperature change is poorly known. Felis et al. show that the GBR experienced a much steeper temperature gradient during the last deglaciation, suggesting it may be more resilient than previously thought.

[1] Ice core records of polar temperatures and greenhouse gases document abrupt millennial-scale oscillations that suggest the reduction or shutdown of thermohaline Circulation (THC) in the North Atlantic Ocean may induce the abrupt cooling in the northern hemisphere. It remains unknown, however, whether the sea surface temperature (SST) is cooling or warming in the Kuroshio of the Northwestern Pacific during the cooling event. Here we present an AMS 14C-dated foraminiferal Mg/Ca SST record from the central Okinawa Trough and document that the SST variations exhibit two steps of warming since 21 ka — at 14.7 ka and 12.8 ka, and a cooling (∼1.5°C) during the interval of the Younger Dryas. By contrast, we observed no SST change or oceanic warming (∼1.5–2°C) during the episodes of Northern Hemisphere cooling between ∼21–40 ka. We therefore suggest that the “Antarctic-like” timing and amplitude of millennial-scale SST variations in the subtropical Northwestern Pacific between 20–40 ka may have been determined by rapid ocean adjustment processes in response to abrupt wind stress and meridional temperature gradient changes in the North Pacific.

[1] Observations and an ocean box model are combined in order to test the adequacy of the freshwater forcing hypothesis to explain abrupt climate change given the uncertainties in the parameterization of vertical buoyancy transport in the ocean. The combination is carried out using Bayesian stochastic inversion, which allows us to infer changes in the mass balance of Northern Hemisphere (NH) ice sheets and in the meridional transports of mass and heat in the Atlantic Ocean that would be required to explain Dansgaard-Oeschger Interstadials (DOIs) from 30 to 39 kyr B.P. The mean sea level changes implied by changes in NH ice sheet mass balance agree in amplitude and timing with reconstructions from the geologic record, which gives some support to the freshwater forcing hypothesis. The inversion suggests that the duration of the DOIs should be directly related to the growth of land ice. Our results are unaffected by uncertainties in the representation of vertical buoyancy transport in the ocean. However, the solutions are sensitive to assumptions about physical processes at polar latitudes.

[1] We analyzed the high-resolution foraminifer isotope records, total organic carbon (TOC), and opal content from an Okinawa Trough core MD012404 in order to estimate the monsoon hydrography and productivity changes in the East China Sea (ECS) of the tropical western Pacific over the past 100,000 years. The variability shown in the records on orbital time scales indicates that high TOC intervals coincide with the increases of boreal May–September insolation driven by precession cycles (∼21 ka), implying a strong connection to the variations in monsoons. We also observed possibly nearly synchronous, millennial-scale changes of the ECS surface hydrography (mainly driven by salinity changes but also by temperature effects) and productivity coincident with monsoon events in the Hulu/Dongge stalagmite isotope records. We found that increased freshening and high productivity correlate with high monsoon intensity in interstadials. This study suggests that the millennial-scale changes in monsoon hydrography and productivity in the ECS are remarkable and persistent features over the past 100,000 years.

International audience; [1] To develop a better understanding of the abrupt Dansgaard-Oeschger mode of climate change, it is essential that we establish whether the ice sheets are actively involved, as trigger or amplifier, or whether they merely respond in a passive manner. This requires careful assessment of the fundamental issues of magnitude and phasing of global ice volume fluctuations within marine isotope stage 3 (MIS 3), which to date remain enigmatic. We review recent advances in observational studies pertaining to these key issues and discuss the implications for modeling studies. Our aim is to construct a robust stratigraphic framework for the MIS 3 period regarding sea level variability, using the most up-to-date arguments available by combining insights from both modeling and observational approaches.

The Last Interglacial Global Mean Sea Level is believed to be 6 to 9m above the present and might have two distinct maxima. Here, we discuss the possible fluctuations and their implications for ice sheet evolution.

The overpressure field around an M68 tank cannon firing an M735 round was studied. Pressure transducers were located from 15 to 400 calibers from the muzzle and at 30 degree increments around the gun. The investigation yielded a detailed picture of the flow field, as displayed by overpressure traces. Comparisons of the overpressure data with a prediction method show better agreement for the measured points nearer to the muzzle. The peak overpressure, time-of-arrival, and positive-phase-duration data will be used together with other gun blast data to modify and improve the present prediction method. Observed anomalous pulses were also investigated but their origins remain unknown.

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