Abstract: Climate And Water Cycle Reconstruction Over The Last Centuries And Prediction Should Be Improved In The Southern Hemisphere (E.g. Last Ipcc Report). First, Direct Observations Are Scarce (E.g. In Antarctica, Mainly Basic Automatic Weather Station – Aws – Only Since The 50’s And Satellite Observations). As A Consequence, Climate And Water Cycle Reconstructions Are Largely Dependent On Proxy Measurements Such As Water Isotopes In Polar Ice Cores, Even Over The Last Century. Second, Climate And Water Cycle Reconstructions Using Models Should Be Improved. In Particular, Problems Have Been Identified For (1) Estimation Of Precipitation Amounts (Large Discrepancies Among Models Over The Austral Ocean And The Ice-sheet), (2) Description Of Particular Atmospheric Processes Associated With Cloud Microphysics And Exchanges Between Surface And Atmosphere In Polar Regions And (3) Seasonal To Interannual Evolution Of The Locations Of The Westerlies And Subtropical Jet And Associated Air Mass Trajectories. The Last Aspect Has Important Direct Consequences For The Atmospheric Dynamics In This Region But Also Indirect Consequences Such As The Links Between Westerlies, Co2 Outgassing And Sea Ice Extent In The Austral Ocean (Saunders Et Al. 2018; Menviel Et Al. 2018; Holland And Kwok, 2012). With The Objectives To Provide (1) A Better Description Of Water Cycle Dynamic In The Southern Ocean At Annual And Interannual Scales And (2) An Improved Transfer Function Between Climate / Water Cycle And Water Isotopes In This Region, A Bunch Of Instruments Measuring Continuously The Isotopic Composition Of Water In The Water Vapor And In The Precipitation Has Been Installed Over The Last Years Along A Transect From La Réunion To Antarctica.first Results From The Antarctic Instruments Reveal Clear Isotopic Signatures Of Large Scale Water Cycle Features Such As Atmospheric Rivers Dominating The Surface Mass Balance In Antarctica. In La Réunion, An Extensive Study Of The Drivers Of The Isotopic Composition Of The Water Vapor Showed That The Influence Of The Subtropical Westerly Jet Dominates The Water Isotopic Signal At Night. To Connect The Two Regions, An Instrument Is Running On Amsterdam Island Since November 2019 With First Results Showing A Clear Isotopic Signature During The High Pressure And Low Pressure Synoptic Events. Still, No In-depth Study Of The Data Trying To Connect The Isotopic Record In Amsterdam Island To Larger Scale Patterns Of The Water Cycle Has Been Initiated.the Goal Of This Internship Is To Provide The First Analyses Of The Isotopic (Water Vapor And Precipitation) Records On Amsterdam Island With A Comparison With Meteorological Data And Environmental Data Collected In Parallel On The Observatory Of Amsterdam Island (E.g. Gaseous Elemental Mercury). After These First Analyses Of The Data, Comparisons Will Be Performed With Water Isotopic Records In La Réunion Over Selected Events (Subtropical Jet Or Cold Fronts Intrusions). This Study Will Involve Analyses Of Meteorological Maps As Well As Backtrajectories.this Internship Requires Skills For (Python Or R Languages) And Involves Large Interactions Within A Large Research Team.

Abstract: Marine animals equipped with biological and physical electronic sensors have produced long-term data streams on key marine environmental variables, hydrography, animal behavior and ecology. These data are an essential component of the Global Ocean Observing System (GOOS). The Animal Borne Ocean Sensors (AniBOS) network aims to coordinate the long-term collection and delivery of marine data streams, providing a complementary capability to other GOOS networks that monitor Essential Ocean Variables (EOVs), essential climate variables (ECVs) and essential biodiversity variables (EBVs). AniBOS augments observations of temperature and salinity within the upper ocean, in areas that are under-sampled, providing information that is urgently needed for an improved understanding of climate and ocean variability and for forecasting. Additionally, measurements of chlorophyll fluorescence and dissolved oxygen concentrations are emerging. The observations AniBOS provides are used widely across the research, modeling and operational oceanographic communities. High latitude, shallow coastal shelves and tropical seas have historically been sampled poorly with traditional observing platforms for many reasons including sea ice presence, limited satellite coverage and logistical costs. Animal-borne sensors are helping to fill that gap by collecting and transmitting in near real time an average of 500 temperature-salinity-depth profiles per animal annually and, when instruments are recovered (∼30% of instruments deployed annually, n = 103 ± 34), up to 1,000 profiles per month in these regions. Increased observations from under-sampled regions greatly improve the accuracy and confidence in estimates of ocean state and improve studies of climate variability by delivering data that refine climate prediction estimates at regional and global scales. The GOOS Observations Coordination Group (OCG) reviews, advises on and coordinates activities across the global ocean observing networks to strengthen the effective implementation of the system. AniBOS was formally recognized in 2020 as a GOOS network. This improves our ability to observe the ocean’s structure and animals that live in them more comprehensively, concomitantly improving our understanding of global ocean and climate processes for societal benefit consistent with the UN Sustainability Goals 13 and 14: Climate and Life below Water. Working within the GOOS OCG framework ensures that AniBOS is an essential component of an integrated Global Ocean Observing System.

Abstract: Understanding the demographic responses of wild animal populations to different factors is fundamental to make reliable prediction of population dynamics. Both bottom–up processes and top–down regulation operate in terrestrial and marine ecosystems, but their relative contribution remains insufficiently known. In addition, direct weather effects on demographic rates have been overlooked in marine ecosystems and inferences on the demographic effects of environmental drivers were overwhelmingly made from single study sites. Here, we evaluate the relative effects of bottom–up, top–down and weather processes on four vital rates and on population growth rates of a long-lived seabird, the snow petrel Pagodroma nivea, within three different breeding colonies. We used multistate capture–recapture modelling and perturbation analyses from a matrix population model based on a 36-year-long (1981–2017) individual monitoring dataset to quantify the different drivers (predation, climatic and weather covariates) of probabilities of survival, breeding, hatching and fledging according to colony, sex and breeding status of individuals. Results show that bottom–up forces and local weather affected breeding parameters, and that survival was driven by top–down regulation pressure and bottom–up processes. Breeding parameters differed between colonies and survival was sex-specific. Sensitivity analysis revealed that population regulation was mainly driven by bottom–up processes and that top–down processes played a minor role. However, there were major differences between colonies about the importance of how local weather processes affected population growth rate. Our study brings new insights into the drivers of demographic processes in a marine meso-predator, and how these drivers vary according to colonies and individual characteristics. We emphasize the importance of considering multiple study sites to make robust inferences on the effects of environmental drivers on wildlife demography. More generally, robust conclusions about the importance of environmental drivers on demography rely on considering multiple causal effects at multiple sites, while accounting for individual characteristics.

Abstract: Obtaining Precise Continuous Measurements Of Water Vapor Isotopic Composition In Dry Places (Polar Or High-altitude Regions) Is An Important Challenge. The Current Limitation Is The Strong Influence Of Humidity On The Measured Water Isotopic Composition By Laser Spectroscopy Instruments For Low Humidity Levels (Below 3000 Ppmv). This Problem Is Addressed By Determining The Relationships Between Humidity And Measured δ18o And δD Of Known Water Standards. Here, We Present The Development Of A Robust Field Instrument Able To Generate Water Vapor, Down To 70 Ppmv, At Very Stable Humidity Levels (Average 1σ Lower Than 10 Ppmv). This Instrument, Operated By A Raspberry Interface, Can Be Coupled To A Commercial Laser Spectroscopy Instrument. We Checked The Stability Of The System As Well As Its Accuracy When Expressing The Measured Isotopic Composition Of Water Vapor On The Vsmow–slap (Vienna Standard Mean Ocean Water – Standard Light Antarctic Precipitation) Scale. It Proved To Be Highly Stable During Autonomous Operation Over More Than 1 Year At The East Antarctic Concordia And Dumont D'urville Stations.

Abstract: Immigration is a major demographic parameter shaping population dynamics and is an important driver of eco-evolutionary patterns, but the fitness consequences for individuals following their settlement to a new population (immigrants) remain poorly tested in wild animal populations, particularly among long-lived species. Here we show that immigrants have a lower fitness than residents in three wild seabird populations (wandering albatross Diomedea exulans, southern fulmar Fulmarus glacialoides, snow petrel Pagodroma nivea). Across all species and during a 32-year period, immigrants made on average −9 to 29% fewer breeding attempts, had 5–31% fewer fledglings, had 2–16% lower breeding success and produced 6–46% fewer recruits. Female immigration and male residency were also favored through differences in breeding performance. We provide evidence for selection against immigrants in wild populations of long-lived species and our results are consistent with female-biased dispersal in birds being driven by asymmetric limiting resources and the competitive ability of dispersers vs. non-dispersers.