D'Asaro
Eric A.
D'Asaro
Eric A.
No Thumbnail Available
25 results
Search Results
Now showing
1 - 20 of 25
-
ArticleInnovative nitrogen sensor maps the North Pacific oxygen minimum zone(The Oceanography Society, 2018-03) McNeil, Craig L. ; D'Asaro, Eric A. ; Reed, Andrew ; Altabet, Mark A. ; Bourbonnais, Annie ; Beaverson, Chris
-
Technical ReportThe benthic boundary layer experiment on the Hatteras Abyssal Plain : current and temperature observations(Woods Hole Oceanographic Institution, 1981-02) Spencer, Ann ; D'Asaro, Eric A. ; Armi, LaurenceThe near bottom density and velocity fields above the Hatteras abyssal plain were observed with a current/temperature measuring array and a towed-yo-yoing profiler. This report describes the array data and includes details of calibration and data quality. Sources of direction error were diagnosed from vane and compass performance and bearing direction .
-
ArticleAn ocean coupling potential intensity index for tropical cyclones(John Wiley & Sons, 2013-05-15) Lin, I.-I. ; Black, Peter G. ; Price, James F. ; Yang, C.-Y. ; Chen, Shuyi S. ; Lien, Chun-Chi ; Harr, Patrick ; Chi, N.-H. ; Wu, C.-C. ; D'Asaro, Eric A.Timely and accurate forecasts of tropical cyclones (TCs, i.e., hurricanes and typhoons) are of great importance for risk mitigation. Although in the past two decades there has been steady improvement in track prediction, improvement on intensity prediction is still highly challenging. Cooling of the upper ocean by TC-induced mixing is an important process that impacts TC intensity. Based on detail in situ air-deployed ocean and atmospheric measurement pairs collected during the Impact of Typhoons on the Ocean in the Pacific (ITOP) field campaign, we modify the widely used Sea Surface Temperature Potential Intensity (SST_PI) index by including information from the subsurface ocean temperature profile to form a new Ocean coupling Potential Intensity (OC_PI) index. Using OC_PI as a TC maximum intensity predictor and applied to a 14 year (1998–2011) western North Pacific TC archive, OC_PI reduces SST_PI-based overestimation of archived maximum intensity by more than 50% and increases the correlation of maximum intensity estimation from r2 = 0.08 to 0.31. For slow-moving TCs that cause the greatest cooling, r2 increases to 0.56 and the root-mean square error in maximum intensity is 11 m s−1. As OC_PI can more realistically characterize the ocean contribution to TC intensity, it thus serves as an effective new index to improve estimation and prediction of TC maximum intensity.
-
ArticleThe LatMix summer campaign : submesoscale stirring in the upper ocean(American Meteorological Society, 2015-08) Shcherbina, Andrey Y. ; Sundermeyer, Miles A. ; Kunze, Eric ; D'Asaro, Eric A. ; Badin, Gualtiero ; Birch, Daniel ; Brunner-Suzuki, Anne-Marie E. G. ; Callies, Joern ; Cervantes, Brandy T. Kuebel ; Claret, Mariona ; Concannon, Brian ; Early, Jeffrey ; Ferrari, Raffaele ; Goodman, Louis ; Harcourt, Ramsey R. ; Klymak, Jody M. ; Lee, Craig M. ; Lelong, M.-Pascale ; Levine, Murray D. ; Lien, Ren-Chieh ; Mahadevan, Amala ; McWilliams, James C. ; Molemaker, M. Jeroen ; Mukherjee, Sonaljit ; Nash, Jonathan D. ; Ozgokmen, Tamay M. ; Pierce, Stephen D. ; Ramachandran, Sanjiv ; Samelson, Roger M. ; Sanford, Thomas B. ; Shearman, R. Kipp ; Skyllingstad, Eric D. ; Smith, K. Shafer ; Tandon, Amit ; Taylor, John R. ; Terray, Eugene A. ; Thomas, Leif N. ; Ledwell, James R.Lateral stirring is a basic oceanographic phenomenon affecting the distribution of physical, chemical, and biological fields. Eddy stirring at scales on the order of 100 km (the mesoscale) is fairly well understood and explicitly represented in modern eddy-resolving numerical models of global ocean circulation. The same cannot be said for smaller-scale stirring processes. Here, the authors describe a major oceanographic field experiment aimed at observing and understanding the processes responsible for stirring at scales of 0.1–10 km. Stirring processes of varying intensity were studied in the Sargasso Sea eddy field approximately 250 km southeast of Cape Hatteras. Lateral variability of water-mass properties, the distribution of microscale turbulence, and the evolution of several patches of inert dye were studied with an array of shipboard, autonomous, and airborne instruments. Observations were made at two sites, characterized by weak and moderate background mesoscale straining, to contrast different regimes of lateral stirring. Analyses to date suggest that, in both cases, the lateral dispersion of natural and deliberately released tracers was O(1) m2 s–1 as found elsewhere, which is faster than might be expected from traditional shear dispersion by persistent mesoscale flow and linear internal waves. These findings point to the possible importance of kilometer-scale stirring by submesoscale eddies and nonlinear internal-wave processes or the need to modify the traditional shear-dispersion paradigm to include higher-order effects. A unique aspect of the Scalable Lateral Mixing and Coherent Turbulence (LatMix) field experiment is the combination of direct measurements of dye dispersion with the concurrent multiscale hydrographic and turbulence observations, enabling evaluation of the underlying mechanisms responsible for the observed dispersion at a new level.
-
ArticleVariability of near-surface circulation and sea surface salinity observed from Lagrangian drifters in the northern Bay of Bengal during the Waning 2015 Southwest Monsoon(The Oceanography Society, 2016-06) Hormann, Verena ; Centurioni, Luca R. ; Mahadevan, Amala ; Essink, Sebastian ; D'Asaro, Eric A. ; Kumar, B. PraveenA dedicated drifter experiment was conducted in the northern Bay of Bengal during the 2015 waning southwest monsoon. To sample a variety of spatiotemporal scales, a total of 36 salinity drifters and 10 standard drifters were deployed in a tight array across a freshwater front. The salinity drifters carried for the first time a revised sensor algorithm, and its performance during the 2015 field experiment is very encouraging for future efforts. Most of the drifters were quickly entrained in a mesoscale feature centered at about 16.5°N, 89°E and stayed close together during the first month of observations. While the eddy was associated with rather homogeneous temperature and salinity characteristics, much larger variability was found outside of it toward the coastline, and some of the observed salinity patches had amplitudes in excess of 1.5 psu. To particularly quantify the smaller spatiotemporal scales, an autocorrelation analysis of the drifter salinities for the first two deployment days was performed, indicating not only spatial scales of less than 5 km but also temporal variations of the order of a few hours. The hydrographic measurements were complemented by first estimates of kinematic properties from the drifter clusters, however, more work is needed to link the different observed characteristics.
-
ArticleDiagnosing frontal dynamics from observations using a variational approach(American Geophysical Union, 2022-09-30) Cutolo, Eugenio ; Pascual, Ananda ; Ruiz, Simón ; Johnston, T. M. Shaun ; Freilich, Mara ; Mahadevan, Amala ; Shcherbina, Andrey ; Poulain, Pierre‐Marie ; Ozgokmen, Tamay ; Centurioni, Luca R. ; Rudnick, Daniel L. ; D’Asaro, EricIntensive hydrographic and horizontal velocity measurements collected in the Alboran Sea enabled us to diagnose the three‐dimensional dynamics of a frontal system. The sampled domain was characterized by a 40 km diameter anticyclonic eddy, with an intense front on its eastern side, separating the Atlantic and Mediterranean waters. Here, we implemented a multi‐variate variational analysis (VA) to reconstruct the hydrographic fields, combining the 1‐km horizontal resolution of the Underway Conductivity‐Temperature‐Depth (CTD) system with information on the flow shape from the Acoustic Doppler Current Profiler velocities. One advantage of the VA is given by the physical constraint, which preserves fine‐scale gradients better than the classical optimal interpolation (OI). A comparison between real drifter trajectories and virtual particles advected in the mapping quantified the improvements in the VA over the OI, with a 15% larger skill score. Quasi‐geostrophic (QG) and semi‐geostrophic (SG) omega equations enabled us to estimate the vertical velocity (w) which reached 40 m/day on the dense side of the front. How nutrients and other passive tracers leave the mixed‐layer and subduct is estimated with 3D advection from the VA, which agreed with biological sampling from traditional CTD casts at two eddy locations. Downwelling warm filaments are further evidence of subduction, in line with the w from SG, but not with QG. SG better accounted for the along‐isopycnal component of w in agreement with another analysis made on isopycnal coordinates. The multi‐platform approach of this work and the use of variational methods improved the characterization and understanding of (sub)‐mesoscale frontal dynamics.
-
ArticleSupplement to physical exchanges at the air–sea interface : UK–SOLAS field measurements(American Meteorological Society, 2009-05) Brooks, Ian M. ; Yelland, Margaret J. ; Upstill-Goddard, Robert C. ; Nightingale, Philip D. ; Archer, Stephen D. ; D'Asaro, Eric A. ; Beale, Rachael ; Beatty, Cory ; Blomquist, Byron ; Bloom, A. Anthony ; Brooks, Barbara J. ; Cluderay, John ; Coles, David ; Dacey, John W. H. ; DeGrandpre, Michael D. ; Dixon, Jo ; Drennan, William M. ; Gabriele, Joseph ; Goldson, Laura E. ; Hardman-Mountford, Nick ; Hill, Martin K. ; Horn, Matt ; Hsueh, Ping-Chang ; Huebert, Barry ; De Leeuw, Gerrit ; Leighton, Timothy G. ; Liddicoat, Malcolm ; Lingard, Justin J. N. ; McNeil, Craig L. ; McQuaid, James B. ; Moat, Bengamin I. ; Moore, Gerald ; Neill, Craig L. ; Norris, Sarah J. ; O'Doherty, Simon ; Pascal, Robin W. ; Prytherch, John ; Rebozo, Mike ; Sahlee, Erik ; Salter, Matt ; Schuster, Ute ; Skjelvan, Ingunn ; Slagter, Hans ; Smith, Michael H. ; Smith, Paul D. ; Srokosz, Meric ; Stephens, John A. ; Taylor, Peter K. ; Telszewski, Maciej ; Walsh, Roisin ; Ward, Brian ; Woolf, David K. ; Young, Dickon ; Zemmelink, Hendrik J.
-
Technical ReportFlow structures of the benthic ocean(Woods Hole Oceanographic Institution, 1980-11) Armi, Laurence ; D'Asaro, Eric A.Three-dimensional structure of the near-bottom density field was observed with a towed yo-yoing profiler and a fixed current/temperature measuring array on the Hatteras abyssal plain. A great variety of structures were seen. Immediately above the bottom a well-mixed bottom layer extends vertically 5-60 m, with less than 1 m°C potential temperature change. This mixed layer is often capped by a region of strong vertical potential temperature gradient, with up to 100-m°C potential temperature change in -10 m. The boundary layer may be uniform for 10 km or exhibit a bottom temperature gradient of up to 20 m°C/ km. Interior layers of nearly constant potential temperature and horizontal extent of 2-100 km are seen -25% of the time above the bottom mixed layer. When an interior layer is present, the bottom mixed layer is thinner. On many occasions an interior layer was seen to be horizontally continuous with the bottom mixed layer, suggesting formation of interior layers by detachment of the bottom mixed layer. A benthic front was observed. Differential horizontal advection is required to explain the observed structures. Velocity fluctuations above I cph increase in energy near the bottom, presumably a signature of turbulence in the mixed layer;these fluctuations are modulated by the passage of structures observed in the moored record.
-
ArticleCoherent pathways for vertical transport from the Surface Ocean to Interior(American Meteorological Society, 2020-11-01) Mahadevan, Amala ; Pascual, Ananda ; Rudnick, Daniel L. ; Ruiz, Simon ; Tintoré, Joaquín ; D'Asaro, Eric A.A long-standing challenge in oceanography is the observing, modeling, and prediction of vertical transport, which links the sunlit and atmospherically mediated surface boundary layer with the deeper ocean. Vertical motions play a critical role in the exchange of heat, freshwater, and biogeochemical tracers between the surface and the ocean interior. The most intense vertical velocities occur at horizontal scales less than 10 km, making them difficult to observe in the ocean and to resolve in models. Understanding how finescale turbulent motions and 0.1–10 km submesoscale processes contribute to the large-scale budgets of nutrients, oxygen, carbon, and heat and affect sea surface temperature, the air–sea exchange of gases, and the carbon cycle is one of the key challenges in oceanography.
-
ArticlePhysical exchanges at the air–sea interface : UK–SOLAS field measurements(American Meteorological Society, 2009-05) Brooks, Ian M. ; Bloom, A. Anthony ; Brooks, Barbara J. ; Lingard, Justin J. N. ; McQuaid, James B. ; Norris, Sarah J. ; Smith, Michael H. ; Smith, Paul D. ; Yelland, Margaret J. ; Moat, Bengamin I. ; Pascal, Robin W. ; Prytherch, John ; Srokosz, Meric ; Taylor, Peter K. ; Upstill-Goddard, Robert C. ; Salter, Matt ; Nightingale, Philip D. ; Archer, Stephen D. ; Beale, Rachael ; Dixon, Jo ; Goldson, Laura E. ; Hardman-Mountford, Nick ; Liddicoat, Malcolm ; Moore, Gerald ; Stephens, John A. ; D'Asaro, Eric A. ; McNeil, Craig L. ; Beatty, Cory ; DeGrandpre, Michael D. ; Blomquist, Byron ; Huebert, Barry ; Cluderay, John ; Zemmelink, Hendrik J. ; Coles, David ; Hsueh, Ping-Chang ; Leighton, Timothy G. ; Dacey, John W. H. ; Drennan, William M. ; Rebozo, Mike ; Sahlee, Erik ; Gabriele, Joseph ; Hill, Martin K. ; Horn, Matt ; De Leeuw, Gerrit ; Neill, Craig ; Skjelvan, Ingunn ; O'Doherty, Simon ; Walsh, Roisin ; Young, Dickon ; Schuster, Ute ; Telszewski, Maciej ; Slagter, Hans ; Ward, Brian ; Woolf, David K.As part of the U.K. contribution to the international Surface Ocean–Lower Atmosphere Study, a series of three related projects—DOGEE, SEASAW, and HiWASE—undertook experimental studies of the processes controlling the physical exchange of gases and sea spray aerosol at the sea surface. The studies share a common goal: to reduce the high degree of uncertainty in current parameterization schemes. The wide variety of measurements made during the studies, which incorporated tracer and surfactant release experiments, included direct eddy correlation fluxes, detailed wave spectra, wind history, photographic retrievals of whitecap fraction, aerosol-size spectra and composition, surfactant concentration, and bubble populations in the ocean mixed layer. Measurements were made during three cruises in the northeast Atlantic on the RRS Discovery during 2006 and 2007; a fourth campaign has been making continuous measurements on the Norwegian weather ship Polarfront since September 2006. This paper provides an overview of the three projects and some of the highlights of the measurement campaigns.
-
ArticleTechnological advancements in observing the upper ccean in the Bay of Bengal : education and capacity building(The Oceanography Society, 2016-06) Tandon, Amit ; D'Asaro, Eric A. ; Stafford, Kathleen M. ; Sengupta, Debasis ; Ravichandran, M. ; Baumgartner, Mark F. ; Venkatesan, Ramasamy ; Paluszkiewicz, TheresaBecause the monsoon strongly affects India, there is a clear need for indigenous expertise in advancing the science that underlies monsoon prediction. The safety of marine transport in the tropics relies on accurate atmospheric and ocean environment predictions on weekly and longer time scales in the Indian Ocean. This need to better forecast the monsoon motivates the United States to advance basic research and support training of early career US scientists in tropical oceanography. Earlier Indian field campaigns and modeling studies indicated that an improved understanding of the interactions between the upper ocean and the atmosphere in the Bay of Bengal at finer spatial and temporal scales could lead to improved intraseasonal monsoon forecasts. The joint US Air-Sea Interactions Regional Initiative (ASIRI) and the Indian Ocean Mixing and Monsoon (OMM) program studied these interactions, resulting in scientific advances described by articles in this special issue of Oceanography. In addition to these scientific advances, and while also developing long-lasting collaborations and building indigenous Indian capability, a key component of these programs is training early career scientists from India and the United States. Training has been focusing on fine-scale and mixing studies of the upper ocean, air-sea interactions, and marine mammal research. Advanced methods in instrumentation, autonomous robotic platforms, experimental design, data analysis, and modeling have been emphasized. Students and scientists from India and the United States at all levels have been participating in joint cruises on Indian and US research vessels and in training participants in modern tools and methods at summer schools, at focused research workshops, and during research visits. Such activities are building new indigenous capability in India, training a new cadre of US scientists well versed in monsoon air-sea interaction, and forging strong links between Indian and US oceanographic institutions.
-
ArticleAutonomous multi-platform observations during the Salinity Processes in the Upper-ocean Regional Study(Oceanography Society, 2017-06) Lindstrom, Eric ; Shcherbina, Andrey Y. ; Rainville, Luc ; Farrar, J. Thomas ; Centurioni, Luca R. ; Dong, Shenfu ; D'Asaro, Eric A. ; Eriksen, Charles C. ; Fratantoni, David M. ; Hodges, Benjamin A. ; Hormann, Verena ; Kessler, William S. ; Lee, Craig M. ; Riser, Stephen C. ; St. Laurent, Louis C. ; Volkov, Denis L.The Salinity Processes in the Upper-ocean Regional Study (SPURS) aims to understand the patterns and variability of sea surface salinity. In order to capture the wide range of spatial and temporal scales associated with processes controlling salinity in the upper ocean, research vessels delivered autonomous instruments to remote sites, one in the North Atlantic and one in the Eastern Pacific. Instruments sampled for one complete annual cycle at each of these two sites, which are subject to contrasting atmospheric forcing. The SPURS field programs coordinated sampling from many different platforms, using a mix of Lagrangian and Eulerian approaches. This article discusses the motivations, implementation, and first results of the SPURS-1 and SPURS-2 programs.
-
ArticleObservations of the cold wake of Typhoon Fanapi (2010)(John Wiley & Sons, 2013-01-19) Mrvaljevic, Rosalinda K. ; Black, Peter G. ; Centurioni, Luca R. ; Chang, Ya-Ting ; D'Asaro, Eric A. ; Jayne, Steven R. ; Lee, Craig M. ; Lien, Ren-Chieh ; Lin, I.-I. ; Morzel, Jan ; Niiler, Pearn P. ; Rainville, Luc ; Sanford, Thomas B.Several tens of thousands of temperature profiles are used to investigate the thermal evolution of the cold wake of Typhoon Fanapi, 2010. Typhoon Fanapi formed a cold wake in the Western North Pacific Ocean on 18 September characterized by a mixed layer that was >2.5 °C cooler than the surrounding water, and extending to >80 m, twice as deep as the preexisting mixed layer. The initial cold wake became capped after 4 days as a warm, thin surface layer formed. The thickness of the capped wake, defined as the 26 °C–27 °C layer, decreased, approaching the background thickness of this layer with an e-folding time of 23 days, almost twice the e-folding lifetime of the Sea Surface Temperature (SST) cold wake (12 days). The wake was advected several hundreds of kilometers from the storm track by a preexisting mesoscale eddy. The observations reveal new intricacies of cold wake evolution and demonstrate the challenges of describing the thermal structure of the upper ocean using sea surface information alone.
-
ArticleFrontal convergence and vertical velocity measured by drifters in the Alboran Sea(American Geophysical Union, 2021-03-24) Tarry, Daniel R. ; Essink, Sebastian ; Pascual, Ananda ; Ruiz, Simon ; Poulain, Pierre Marie ; Ozgokmen, Tamay M. ; Centurioni, Luca R. ; Farrar, J. Thomas ; Shcherbina, Andrey Y. ; Mahadevan, Amala ; D'Asaro, Eric A.Horizontal and vertical motions associated with mesoscale (10–100 km) and submesoscale (1–10 km) features, such as fronts, meanders, eddies, and filaments, play a critical role in redistributing physical and biogeochemical properties in the ocean. This study makes use of a multiplatform data set of 82 drifters, a Lagrangian float, and profile timeseries of temperature and salinity, obtained in a ∼1-m/s semipermanent frontal jet in the Alboran Sea as part of CALYPSO (Coherent Lagrangian Pathways from the Surface Ocean to Interior). Drifters drogued at ∼1-m and 15-m depth capture the mesoscale and submesoscale circulation aligning along the perimeter of fronts due to horizontal shear. Clusters of drifters are used to estimate the kinematic properties, such as vorticity and divergence, of the flow by fitting a bivariate plane to the horizontal drifter velocities. Clusters with submesoscale length scales indicate normalized vorticity ζ/f > 1 with Coriolis frequency f and normalized divergence of (1) occurring in patches along the front, with error variance around 10%. By computing divergence from drifter clusters at two different depths, we estimate minimum vertical velocity of (−100 m day−1) in the upper 10 m of the water column. These results are at least twice as large as previous estimates of vertical velocity in the region. Location, magnitude, and timing of the convergence are consistent with behavior of a Lagrangian float subducting in the center of a drifter cluster. These results improve our understanding of frontal subduction and quantify convergence and vertical velocity using Lagrangian tools.
-
ArticleInertial oscillations and frontal processes in an Alboran Sea Jet: effects on divergence and vertical transport(American Geophysical Union, 2023-02-15) Esposito, Giovanni ; Donnet, Sebastien ; Berta, Maristella ; Shcherbina, Andrey Y. ; Freilich, Mara ; Centurioni, Luca ; D’Asaro, Eric A. ; Farrar, J. Thomas ; Johnston, T. M. Shaun ; Mahadevan, Amala ; Özgökmen, Tamay ; Pascual, Ananda ; Poulain, Pierre‐Marie ; Ruiz, Simón ; Tarry, Daniel R. ; Griffa, AnnalisaVertical transport pathways in the ocean are still only partially understood despite their importance for biogeochemical, pollutant, and climate applications. Detailed measurements of a submesoscale frontal jet in the Alboran Sea (Mediterranean Sea) during a period of highly variable winds were made using cross‐frontal velocity, density sections and dense arrays of surface drifters deployed across the front. The measurements show divergences as large as ±f implying vertical velocities of order 100 m/day for a ≈ 20 m thick surface layer. Over the 20 hr of measurement, the divergences made nearly one complete oscillation, suggesting an important role for near‐inertial oscillations. A wind‐forced slab model modified by the observed background frontal structure and with initial conditions matched to the data produces divergence oscillations and pattern compatible with that observed. Significant differences, though, are found in terms of mean divergence, with the data showing a prevalence of negative, convergent values. Despite the limitations in data sampling and model uncertainties, this suggests the contribution of other dynamical processes. Turbulent boundary layer processes are discussed, as a contributor to enhance the observed convergent phase. Water mass properties suggest that symmetric instabilities might also be present but do not play a crucial role, while downward stirring along displaced isopycnals is observed.Plain Language SummaryVertical transport pathways are essential for the exchange of properties between the surface and the deeper layers of the ocean. Despite the recognized role of vertical dynamics in biogeochemical and climate applications, it is still only partially understood. This is principally due to observational challenges. Vertical transport pathways are generally very localized processes and are associated with vertical velocities comparable to instrumental uncertainty. In this work, we focus on vertical processes occurring along a front at the edge of an eddy in the Mediterranean Sea. The paper combines the analysis of multiple observations with the use of an idealized numerical model to isolate and study surface divergence patterns. These analyses allow the investigation of the role of the wind forcing and of small‐scale ocean processes in vertical transport.Key PointsDivergence and vertical velocity oscillations are observed at a submesoscale front on the edge of an anticyclone in the Alboran SeaNear‐inertial oscillations play a major role in the observed divergence oscillatory pattern as suggested by a modified slab model of a wind‐forced frontal jetTurbulent boundary layer processes and symmetric instabilities can contribute to differences between modeled and observed vertical dynamics
-
Working PaperEXPORTS North Atlantic eddy tracking(NASA STI Program and Woods Hole Oceanographic Institution, 2022-10) Erickson, Zachary K. ; Fields, Erik ; Omand, Melissa M. ; Johnson, Leah ; Thompson, Andrew F. ; D'Asaro, Eric A. ; Carvalho, Filipa ; Dove, Lilian A. ; Lee, Craig M. ; Nicholson, David P. ; Shilling, Geoff ; Cetinić, Ivona ; Siegel, David A.The EXPORTS North Atlantic field campaign (EXPORTS-NA) of May 2021 used a diverse array of ship-based and autonomous platforms to measure and quantify processes leading to carbon export in the open ocean. The success of this field program relied heavily on the ability to make measurements following a Lagrangian trajectory within a coherent, retentive eddy (Sections 1, 2). Identifying an eddy that would remain coherent and retentive over the course of a monthlong deployment was a significant challenge that the EXPORTS team faced. This report details the processes and procedures used by the primarily shore-based eddy tracking team to locate, track, and sample with autonomous assets such an eddy before and during EXPORTS-NA.
-
Working PaperEXport Processes in the Ocean from RemoTe Sensing (EXPORTS) North Atlantic sensor calibration and intercalibration documents(NASA STI Program and Woods Hole Oceanographic Institution, 2023-10-11) Siegel, David A. ; Cetinić, Ivona ; Thompson, Andrew F. ; Nelson, Norman B. ; Sten, Michaela ; Omand, Melissa M. ; Traylor, Shawnee ; Nicholson, David P. ; D'Asaro, Eric A. ; Zhang, Xiaodong ; Erickson, Zachary K. ; Johnson, Leah ; Soto Ramos, IniaThe following documents collect information regarding the calibration and intercalibration of various sensors that were deployed during the North Atlantic field component of the NASA EXPORTS project (EXPORTS NA), which took place between May 4 and June 1, 2021 (Johnson et al., 2023). The EXPORTS NA campaign was designed to to provide a contrasting end member to the earlier North Pacific field campaign, and focused on carbon export associated with the North Atlantic spring bloom in which gravitational sinking of organic particles, the physical advection and mixing, and active transport by vertically migrating zooplankton are all expected to provide significant flux pathways. During EXPORTS NA data sets were collected from a variety of shipbased, autonomously-piloted, and Lagrangian platforms. Intercalibration activities were tasked to different groups within the EXPORTS project team. Team leads and contact information are listed below. The overarching goal of these activities was to identify a trusted sensor, carry out a careful calibration of this sensor, then base any intercalibraiton needs off of this sensor, occasionally propagating information across platforms. Full details of the intercalibration approach, assumptions, and summary are provided in the attached documents. All calibration and intercalibration activities were completed before data set were uplaoded to the NASA SeaBASS data repository. Data related to this cruise can be publicly accessed at: https://seabass.gsfc.nasa.gov/cruise/EXPORTSNA Updates to calibration and intercalibration documents required to reflect revised data sets will also be provided through SeaBASS. Questions concerning referencing these documents or accessing data sets should be directed to Inia Soto Ramos. NASA EXPORTS Science Lead: David Siegel, davesiegel@ucsb.edu NASA EXPORTS Project Scientist: Ivona Cetini´c, ivona.cetinic@nasa.gov NASA EXPORTS Data Manager: Inia Soto Ramos, inia.m.sotoramos@nasa.gov Calibration and intercalibration leads Temperature and salinity sensors: Andy Thompson, andrewt@caltech.edu Chlorophyll fluorescence sensors: Melissa Omand & Kaley Sten, momand@uri.edu Oxygen sensors: Shawnee Traylor & Roo Nicholson, shawnee@mit.edu Optical backscatter sensors: Xiaodong Zhang, Xiaodong.Zhang@usm.edu Lagrangian float sensors: Eric D’Asaro, dasaro@apl.washington.edu Underway sensors: Leah Johnson, leahjohn@uw.edu Underwater Vision Profiler (UVP)-Particle Size Distribution (PSD): David Siegel, davesiegel@ucsb.edu
-
ArticlePrediction of the export and fate of global ocean net primary production : the EXPORTS Science Plan(Frontiers Media, 2016-03-08) Siegel, David A. ; Buesseler, Ken O. ; Behrenfeld, Michael J. ; Benitez-Nelson, Claudia R. ; Boss, Emmanuel S. ; Brzezinski, Mark A. ; Burd, Adrian B. ; Carlson, Craig A. ; D'Asaro, Eric A. ; Doney, Scott C. ; Perry, Mary J. ; Stanley, Rachel H. R. ; Steinberg, Deborah K.Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as its fate in the underlying “twilight zone” where some fraction of exported carbon will be sequestered in the ocean's interior on time scales of months to millennia. Here we present a measurement/synthesis/modeling framework aimed at quantifying the fates of upper ocean NPP and its impacts on the global carbon cycle based upon the EXPORTS Science Plan. The proposed approach will diagnose relationships among the ecological, biogeochemical, and physical oceanographic processes that control carbon cycling across a range of ecosystem and carbon cycling states leading to advances in satellite diagnostic and numerical prognostic models. To collect these data, a combination of ship and robotic field sampling, satellite remote sensing, and numerical modeling is proposed which enables the sampling of the many pathways of NPP export and fates. This coordinated, process-oriented approach has the potential to foster new insights on ocean carbon cycling that maximizes its societal relevance through the achievement of research goals of many international research agencies and will be a key step toward our understanding of the Earth as an integrated system.
-
ArticleTyphoon-ocean interaction in the western North Pacific : Part 1(The Oceanography Society, 2011-12) D'Asaro, Eric A. ; Black, Peter G. ; Centurioni, Luca R. ; Harr, Patrick ; Jayne, Steven R. ; Lin, I.-I. ; Lee, Craig M. ; Morzel, Jan ; Mrvaljevic, Rosalinda K. ; Niiler, Pearn P. ; Rainville, Luc ; Sanford, Thomas B. ; Tang, Tswen YungThe application of new technologies has allowed oceanographers and meteorologists to study the ocean beneath typhoons in detail. Recent studies in the western Pacific Ocean reveal new insights into the influence of the ocean on typhoon intensity.
-
Working PaperEXPORTS Measurements and Protocols for the NE Pacific Campaign(NASA STI Program and Woods Hole Oceanographic Institution, 2021-02) Behrenfeld, Michael J. ; Benitez-Nelson, Claudia R. ; Boss, Emmanuel S. ; Brzezinski, Mark A. ; Buck, Kristen N. ; Buesseler, Ken O. ; Burd, Adrian B. ; Carlson, Craig A. ; Cassar, Nicolas ; Cetinić, Ivona ; Close, Hilary G. ; Craig, Susanne E. ; D'Asaro, Eric A. ; Durkin, Colleen A. ; Estapa, Margaret L. ; Fassbender, Andrea ; Fox, James ; Freeman, Scott ; Gifford, Scott M. ; Gong, Weida ; Graff, Jason R. ; Gray, Deric ; Guidi, Lionel ; Halsey, Kim ; Hansell, Dennis A. ; Haëntjens, Nils ; Horner, Tristan J. ; Jenkins, Bethany D. ; Jones, Janice L. ; Karp-Boss, Lee ; Kramer, Sasha J. ; Lam, Phoebe J. ; Lee, Craig M. ; Lee, Jong-Mi ; Liu, Shuting ; Mannino, Antonio ; Maas, Amy E. ; Marchal, Olivier ; Marchetti, Adrian ; McDonnell, Andrew M. P. ; McNair, Heather ; Menden-Deuer, Susanne ; Morison, Francoise ; Nelson, Norman B. ; Nicholson, David P. ; Niebergall, Alexandria K. ; Omand, Melissa M. ; Passow, Uta ; Perry, Mary J. ; Popp, Brian N. ; Proctor, Chris ; Rafter, Patrick ; Roca-Martí, Montserrat ; Roesler, Collin S. ; Rubin, Edwina ; Rynearson, Tatiana A. ; Santoro, Alyson E. ; Siegel, David A. ; Sosik, Heidi M. ; Soto Ramos, Inia ; Stamieszkin, Karen ; Steinberg, Deborah K. ; Stephens, Brandon M. ; Thompson, Andrew F. ; Van Mooy, Benjamin A. S. ; Zhang, XiaodongEXport Processes in the Ocean from Remote Sensing (EXPORTS) is a large-scale NASA-led and NSF co-funded field campaign that will provide critical information for quantifying the export and fate of upper ocean net primary production (NPP) using satellite information and state of the art technology.