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The Indo‐Pacific Warm Pool (IPWP) is home to the warmest sea surface temperatures in the world oceans, favoring strong tropospheric convection and heavy rainfall. The mechanisms controlling long‐term change in the region’s hydroclimate are still uncertain. Here, we present a 450,000‐year record of precipitation δD from southern Sumatra that records a consistent pattern of glacial isotopic enrichment and interglacial depletion. We synthesize existing paleo‐indicators of precipitation δD and δ18O in the IPWP and compare results with water isotope‐enabled climate simulations of the Last Glacial Maximum (LGM). The simulations show glacial isotopic enrichment over the eastern Indian Ocean extending into the southern IPWP and isotopic depletion over southeast Asia, the west Pacific, and Australia. The pattern of simulated LGM isotopic change agrees generally well with our proxy synthesis. We conclude that reorganization of regional circulation under glacial conditions controls precipitation isotope variability in the IPWP: low‐level tropospheric convergence dominates the signal in the north/east, whereas divergence controls the response in the south/west. Additional sensitivity simulations suggest that the LGM ice sheets and the associated lowering in sea level, rather than decreased greenhouse gases, are responsible for the distinctive spatial pattern in glacial changes of precipitation isotopes and hydroclimate across the IPWP.

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high-and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.(TABLE)Since the pioneering work of D'Arrigo and Jacoby1-3, as well as Mann et al. 4,5, temperature reconstructions of the Common Era have become a key component of climate assessments6-9. Such reconstructions depend strongly on the composition of the underlying network of climate proxies10, and it is therefore critical for the climate community to have access to a community-vetted, quality-controlled database of temperature-sensitive records stored in a self-describing format. The Past Global Changes (PAGES) 2k consortium, a self-organized, international group of experts, recently assembled such a database, and used it to reconstruct surface temperature over continental-scale regions11 (hereafter, ` PAGES2k-2013').This data descriptor presents version 2.0.0 of the PAGES2k proxy temperature database (Data Citation 1). It augments the PAGES2k-2013 collection of terrestrial records with marine records assembled by the Ocean2k working group at centennial12 and annual13 time scales. In addition to these previously published data compilations, this version includes substantially more records, extensive new metadata, and validation. Furthermore, the selection criteria for records included in this version are applied more uniformly and transparently across regions, resulting in a more cohesive data product.This data descriptor describes the contents of the database, the criteria for inclusion, and quantifies the relation of each record with instrumental temperature. In addition, the paleotemperature time series are summarized as composites to highlight the most salient decadal-to centennial-scale behaviour of the dataset and check mutual consistency between paleoclimate archives. We provide extensive Matlab code to probe the database-processing, filtering and aggregating it in various ways to investigate temperature variability over the Common Era. The unique approach to data stewardship and code-sharing employed here is designed to enable an unprecedented scale of investigation of the temperature history of the Common Era, by the scientific community and citizen-scientists alike.

10 pages, 4 figures, A new small wave rider called Surpact was developed for air-sea investigations. It was designed to attach to a drifter or a mooring and to float upon the surface waves in order to measure sea state and atmospheric sea level pressure as well as temperature and salinity at a small fixed depth from the surface. Wind speed is derived from Surpact sea state measurements, and the data are calibrated with colocated Special Sensor Microwave Imager Sounder (SSMIS) wind retrievals during a four-month deployment in the North Atlantic subtropics. Individual 15-minute wind estimates present a root mean square difference on the order of 15% with the SSMIS wind retrievals for wind speeds less than 12 m s-1. The wind retrievals might lag the actual wind changes for moderate to strong winds by an hour. This article discusses the accuracy of these wind retrievals based on in situ data collected during the Strasse cruise in August and September 2012. Temperature and salinity data are also examined. The authors find, under some sunny conditions, radiative warming of the temperature probe reduces the accuracy of some of the daytime temperature data and also affects corresponding salinity estimates. Nonetheless, small realistic daily cycles of near-surface salinity (0.01 psu amplitude) were observed. Also, examples of wind time series collected during salinity drops caused by rainfall during late 2012 in the North Atlantic subtropics indicate no intensification of wind during these rain events, This effort is part of ESA SMOS cal-val projects, and is supported nationally in France by CNES/TOSCA with the Gloscal project, and in Spain at ICM/CSIC by the Spanish national R+D plan (project AYA2010-22062-C05)

Remote sensing of salinity using satellite-mounted microwave radiometers provides new perspectives for studying ocean dynamics and the global hydrological cycle. Calibration and validation of these measurements is challenging because satellite and in situ methods measure salinity differently. Microwave radiometers measure the salinity in the top few centimeters of the ocean, whereas most in situ observations are reported below a depth of a few meters. Additionally, satellites measure salinity as a spatial average over an area of about 100 × 100 km2. In contrast, in situ sensors provide pointwise measurements at the location of the sensor. Thus, the presence of vertical gradients in, and horizontal variability of, sea surface salinity complicates comparison of satellite and in situ measurements. This paper synthesizes present knowledge of the magnitude and the processes that contribute to the formation and evolution of vertical and horizontal variability in near-surface salinity. Rainfall, freshwater plumes, and evaporation can generate vertical gradients of salinity, and in some cases these gradients can be large enough to affect validation of satellite measurements. Similarly, mesoscale to submesoscale processes can lead to horizontal variability that can also affect comparisons of satellite data to in situ data. Comparisons between satellite and in situ salinity measurements must take into account both vertical stratification and horizontal variability.

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M., 2001, INT GEOPHYS SERIES, V77, P337 Torrence C, 1998, B AM METEOROL SOC, V79, P61, DOI 10.1175/1520-0477(1998)0792.0.CO;2 Wachenfeld D., 2007, CLIMATE CHANGE GREAT Waugh DW, 2006, J PHYS OCEANOGR, V36, P526, DOI 10.1175/JPO2865.1 Wheeler MC, 2004, MON WEATHER REV, V132, P1917, DOI 10.1175/1520-0493(2004)1322.0.CO;2 Yueh S., 2012, IEEE INT GEOSC REM S Maes, Christophe Dewitte, Boris Sudre, Joel Garcon, Veronique Varillon, David Institut de Recherche pour le Developpement (IRD); Centre National de la Recherche Scientifique (CNRS) Sea surface salinity data derived from thermosalinograph instruments installed onboard voluntary observing ships are freely distributed by the French Sea Surface Salinity Observation Service (http://www.legos.obs-mip.fr/observations/sss/). The TRMM data were acquired as part of the activities of NASA's Science Mission Directorate, and are archived and distributed by the Goddard Earth Sciences (GES) Data and Information Services Center (DISC). Special thanks go to Cristobal Lopez and Emilio Hernandez-Garcia for providing their code for the FSLE computation, and to Serena Illig for her help on the wavelet analysis. Comments on the original version from Dave Behringer were greatly appreciated, and we would like also to gratefully thank Tangdong Qu and the other anonymous reviewer for their fruitful comments. This work is supported by the Institut de Recherche pour le Developpement (IRD) and by the Centre National de la Recherche Scientifique (CNRS). 0 AMER GEOPHYSICAL UNION WASHINGTON J GEOPHYS RES-OCEANS; The small-scale features in sea surface temperature and salinity fields (SST and SSS) of the Coral Sea are examined using high horizontal spatial and short-term temporal in situ measurements. These features are extracted from thermosalinographs (TSGs) gathered onboard commercial and research vessels and at one long-term fixed station. The analyses are performed along the vessel tracks and the structures of small-scale features are extracted by high-pass spatial filtering the original TSG data. For SSS, it is shown that the features at the scale of mesoscale eddies (approximate to 100 km) vary from about -1.1 to +0.6 psu in the Coral Sea region. Processes sustaining such range include rainfall events, stirring by mesoscale eddies, and the latitudinal displacement of the sharp front associated with the edge of the Western Pacific Warm Pool at the seasonal time scales. The TSG data have revealed the presence of a sharp front (0.4-0.6 psu) between the subtropical and equatorial waters instead of a smooth gradient in the standard SSS climatologies. Within the context of recent remotely sensed observations of salinity, this could represent an important limitation for the validation and calibration of satellite products. In addition to these spatial considerations, temporal variations at one long-term station near Vanuatu show that the coupled air-sea responses to intraseasonal tropical variability, such as the Madden-Julian Oscillation, may have a signature in both SST and SSS fields. However, this response is found to be complex and not necessarily in phase. In the Coral Sea region, our results suggest that MJO-induced variability on SST and SSS exhibit little coherency at the seasonal time scales.

ISI Document Delivery No.: 708HP Times Cited: 8 Cited Reference Count: 77 Cited References: ADAMEC D, 1978, J PHYS OCEANOGR, V8, P1050, DOI 10.1175/1520-0485(1978)0082.0.CO;2 ANDERSON RJ, 1993, J PHYS OCEANOGR, V23, P2153, DOI 10.1175/1520-0485(1993)0232.0.CO;2 Bellanger H., 2007, THESIS ECOLE POLYTEC Bernie DJ, 2005, J CLIMATE, V18, P1190, DOI 10.1175/JCLI3319.1 Bernie DJ, 2007, CLIM DYNAM, V29, P575, DOI 10.1007/s00382-007-0249-6 Bernie DJ, 2008, CLIM DYNAM, V31, P909, DOI 10.1007/s00382-008-0429-z BOUGEAULT P, 1989, MON WEATHER REV, V117, P1872, DOI 10.1175/1520-0493(1989)1172.0.CO;2 Bourles B, 2008, B AM METEOROL SOC, V89, P1111, DOI 10.1175/2008BAMS2462.1 Bourles B, 2002, GEOPHYS RES LETT, V29, DOI 10.1029/2002GL015098 Bourles B, 1999, J GEOPHYS RES-OCEANS, V104, P21151, DOI 10.1029/1999JC900058 Bourles B., 2007, CLIVAR NEWSLETTER EX, V41, P7 Bourras D, 2009, J GEOPHYS RES-OCEANS, V114, DOI 10.1029/2008JC004951 Bunge L, 2007, J GEOPHYS RES-OCEANS, V112, DOI 10.1029/2006JC003704 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Based on a French initiative, AMMA was built by an international scientific group and is currently funded by a large number of agencies, including those in France, the UK, the US, and Africa. It has been the beneficiary of a major financial contribution from the European Community's Sixth Framework Research Program. Detailed information on scientific coordination and funding is available on the AMMA International web site http://www.amma-international.org. We thank Bernard Bourles, the chief scientist of the EGEE program, and all the persons who acquired and prepared the data used in this study as well as the Captain of the RN L'Atalante and his crew for their help during the EGEE-3 cruise. We warmly thank Dr. Gregory Foltz and an anonymous reviewer for their pertinent and useful comments and remarks. 8 SPRINGER HEIDELBERG HEIDELBERG OCEAN DYNAM; A one-dimensional model is used to analyze, at the local scale, the response of the equatorial Atlantic Ocean under different meteorological conditions. The study was performed at the location of three moored buoys of the Pilot Research Moored Array in the Tropical Atlantic located at 10 degrees W, 0 degrees N; 10 degrees W, 6 degrees S; and 10 degrees W, 10 degrees S. During the EGEE-3 (Etude de la circulation oceanique et de sa variabilite dans le Golfe de Guinee) campaign of May-June 2006, each buoy was visited for maintenance during 2 days. On board the ship, high-resolution atmospheric parameters were collected, as were profiles of temperature, salinity, and current. These data are used here to initialize, force, and validate a one-dimensional model in order to study the diurnal oceanic mixed-layer variability. It is shown that the diurnal variability of the sea surface temperatures is mainly driven by the solar heat flux. The diurnal response of the near-surface temperatures to daytime heating and nighttime cooling has an amplitude of a few tenths of degree. The computed diurnal heat budget experiences a net warming tendency of 31 and 27 Wm(-2) at 0 degrees N and 10 degrees S, respectively, and a cooling tendency of 122 Wm(-2) at 6 degrees S. Both observed and simulated mixed-layer depths experience a jump between the nighttime convection phase and the well-stabilized diurnal water column. Its amplitude changes dramatically depending on the meteorological conditions occurring at the stations and reaches its maximum amplitude (similar to 50 m) at 100 degrees S. At 6 degrees and 10 degrees S, the presence of barrier layers is observed, a feature that is clearer at 10 degrees S. Simulated turbulent kinetic energy (11(E) dissipation rates, compared to independent microstructure measurements, show that the model tracks their diurnal evolution reasonably well. It is also shown that the shear and buoyancy productions and the vertical diffusion of TKE all contribute to the supply of TKE, but the buoyancy production is the main source of TKE during the period of the simulation.

[1] Much understanding of the El Niño-Southern Oscillation (ENSO) has been obtained from the analyses of the climate simulations produced for World Climate Research Programme's Coupled Model Intercomparison Project phase 3 (CMIP3). However, most of these analyses do not consider the existence of the Eastern-Pacific (EP) and Central-Pacific (CP) types of ENSO events, which have been increasingly recognized as two distinct types of interannual sea surface temperature (SST) variation in the tropical Pacific. This study uses a regression-Empirical Orthogonal Function method to identify how well these two ENSO types are captured in the pre-industrial simulations of nineteen CMIP3 models. It is concluded that most CMIP3 models (13 out of 19) can produce realistically strong CP ENSOs, but only a few of them (9 out of 19) can produce realistically strong EP ENSOs. Six models that realistically simulate both the EP and CP ENSOs and their intensity ratio are identified. By separating the SST variability into these two types, it is further revealed that the leading periodicity of the simulated EP ENSO is linearly related to the latitudinal width of SST variability and varies from 1 to 5 years. As for the simulated CP ENSO, its leading periodicity is either 2 or 4 years depending on whether its SST variability is located to the east of the dateline or in the western-Pacific warm pool, respectively. The identification produced in this study offers useful information to further understand the two types of ENSO using the CMIP3 models.

The position of the southern boundary of the Pacific warm pool is shown to have been stable since the early Pleistocene, based upon a planktic foraminiferal Mg/Ca-derived reconstruction of subtropical sea surface temperature in the Coral Sea. This contrasts with previous reconstructions showing warm pool contraction from the north and east and means that the early Pleistocene warm pool was more hemispherically asymmetric than its present configuration. The latter was not established until similar to 1Ma, supporting a strengthening of the northern Hadley Cell, which was not replicated in its southern counterpart, prior to the Mid-Pleistocene Transition. Citation: Russon, T., M. Elliot, A. Sadekov, G. Cabioch, T. Correge, and P. De Deckker (2010), Inter-hemispheric asymmetry in the early Pleistocene Pacific warm pool, Geophys. Res. Lett., 37, L11601, doi: 10.1029/2010GL043191.

International audience; Since Last Glacial Maximum (23-19 ka), Earth climate warming and deglaciation occurred in two major steps (Bolling-Allerod and Preboreal), interrupted by a short cooling interval referred to as the Younger Dryas (12.5-11.5 ka B. P.). In this study, three cores (MV-33, MV-66, and MD-40) collected in the central part of Pandora Trough (Gulf of Papua) have been analyzed, and they reveal a detailed sedimentary pattern at millennial timescale. Siliciclastic turbidites disappeared during the Bolling-Allerod and Preboreal intervals to systematically reoccur during the Younger Dryas interval. Subsequent to the final disappearance of the siliciclastic turbidites a calciturbidite occurred during meltwater pulse 1B. The Holocene interval was characterized by a lack of siliciclastic turbidites, relatively high carbonate content, and fine bank-derived aragonitic sediment. The observed millennial timescale sedimentary variability can be explained by sea level fluctuations. During the Last Glacial Maximum, siliciclastic turbidites were numerous when the lowstand coastal system was located along the modern shelf edge. Although they did not occur during the intervals of maximum flooding of the shelf (during meltwater pulses 1A and 1B), siliciclastic turbidites reappear briefly during the Younger Dryas, an interval when sea level rise slowed, stopped, or perhaps even fell. The timing of the calciturbidite coincides with the first reflooding of Eastern Fields Reef, an atoll that remained exposed for most of the glacial stages.