https://faculty.washington.edu/kessler/abstracts/ETPacCirculation.pdf

The circulation of the eastern tropical Pacific: A review

The estimate of surface irradiance on a global scale is possible through radiative transfer calculations using satellite-retrieved surface, cloud, and aerosol properties as input. Computed top-of-atmosphere (TOA) irradiances, however, do not necessarily agree with observation-based values, for example, from the Clouds and the Earth’s Radiant Energy System (CERES). This paper presents a method to determine surface irradiances using observational constraints of TOA irradiance from CERES. A Lagrange multiplier procedure is used to objectively adjust inputs based on their uncertainties such that the computed TOA irradiance is consistent with CERES-derived irradiance to within the uncertainty. These input adjustments are then used to determine surface irradiance adjustments. Observations by the Atmospheric Infrared Sounder (AIRS), Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), CloudSat, and Moderate Resolution Imaging Spectroradiometer (MODIS) that are a part of the NASA ...

/pdf/surface-irradiances-consistent-with-ceres-derived-top-of-3gvklvvwn4.pdf

Surface Irradiances Consistent With CERES-Derived Top-of-Atmosphere Shortwave and Longwave Irradiances

In this paper, we evaluate several timely, daily air-sea heat flux products (NCEP, NCEP2, ERA-Interim and OAFlux/ISCCP) against observations and present the newly developed TropFlux product. This new product uses bias-corrected ERA-interim and ISCCP data as input parameters to compute air-sea fluxes from the COARE v3.0 algorithm. Wind speed is corrected for mesoscale gustiness. Surface net shortwave radiation is based on corrected ISCCP data. We extend the shortwave radiation time series by using ''near real-time'' SWR estimated from outgoing longwave radiation. All products reproduce con- sistent intraseasonal surface net heat flux variations asso- ciated with the Madden-Julian Oscillation in the Indian Ocean, but display more disparate interannual heat flux variations associated with El Nino in the eastern Pacific. They also exhibit marked differences in mean values and seasonal cycle. Comparison with global tropical moored buoy array data, I-COADS and fully independent mooring data sets shows that the two NCEP products display lowest correlation to mooring turbulent fluxes and significant bia- ses. ERA-interim data captures well temporal variability, but with significant biases. OAFlux and TropFlux perform best. All products have issues in reproducing observed longwave radiation. Shortwave flux is much better captured by ISCCP data than by any of the re-analyses. Our ''near real-time'' shortwave radiation performs better than most re-analyses, but tends to underestimate variability over the cold tongues of the Atlantic and Pacific. Compared to independent mooring data, NCEP and NCEP2 net heat fluxes display *0.78 correlation and (65 W m -2 rms-difference, ERA-I performs better (*0.86 correlation and *48 W m -2 ) while OAFlux and TropFlux perform best (*0.9 correlation and *43 W m -2 ). TropFlux hence provides a useful option for

TropFlux: air-sea fluxes for the global tropical oceans—description and evaluation

The VAMOS(1) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was an international field program designed to make observations of poorly understood but critical components of the coupled climate system of the southeast Pacific. This region is characterized by strong coastal upwelling, the coolest SSTs in the tropical belt, and is home to the largest subtropical stratocumulus deck on Earth. The field intensive phase of VOCALS-REx took place during October and November 2008 and constitutes a critical part of a broader CLIVAR program (VOCALS) designed to develop and promote scientific activities leading to improved understanding, model simulations, and predictions of the southeastern Pacific (SEP) coupled ocean-atmosphere-land system, on diurnal to interannual timescales. The other major components of VOCALS are a modeling program with a model hierarchy ranging from the local to global scales, and a suite of extended observations from regular research cruises, instrumented moorings, and satellites. The two central themes of VOCALS-REx focus upon (a) links between aerosols, clouds and precipitation and their impacts on marine stratocumulus radiative properties, and (b) physical and chemical couplings between the upper ocean and the lower atmosphere, including the role that mesoscale ocean eddies play. A set of hypotheses designed to be tested with the combined field, monitoring and modeling work in VOCALS is presented here. A further goal of VOCALS-REx is to provide datasets for the evaluation and improvement of large-scale numerical models. VOCALS-REx involved five research aircraft, two ships and two surface sites in northern Chile. We describe the instrument pay-loads and key mission strategies for these platforms and give a summary of the missions conducted.

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The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx): goals, platforms, and field operations

[1] The mean vertical structure of mesoscale eddies in the Peru-Chile Current System is investigated by combining the historical records of Argo float profiles and satellite altimetry data. A composite average of 420 (526) profiles acquired by Argo floats that surfaced into cyclonic (anticyclonic) mesoscale eddies allowed constructing the mean three-dimensional eddy structure of the eastern South Pacific Ocean. Key differences in their thermohaline vertical structure were revealed. The core of cyclonic eddies (CEs) is centered at ∼150 m depth within the 25.2–26.0 kg m−3 potential density layer corresponding to the thermocline. In contrast, the core of the anticyclonic eddies (AEs) is located below the thermocline at ∼400 m depth impacting the 26.0–26.8 kg m−3 density layer. This difference was attributed to the mechanisms involved in the eddy formation. While intrathermocline CEs would be formed by instabilities of the surface equatorward coastal currents, the subthermocline AEs are likely to be shed by the subsurface poleward Peru-Chile Undercurrent. In the eddy core, maximum temperature and salinity anomalies are of ±1°C and ±0.1, with positive (negative) values for AEs (CEs). This study also provides new insight into the potential impact of mesoscale eddies for the cross-shore transport of heat and salt in the eastern South Pacific. Considering only the fraction of the water column associated with the fluid trapped within the eddies, each CE and AE has a typical volume anomaly flux of ∼0.1 Sv and yields to a heat and salt transport anomaly of ±1–3 × 1011 W and ±3–8 × 103 kg s−1, respectively.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2011JC007134

Vertical structure of mesoscale eddies in the eastern South Pacific Ocean: A composite analysis from altimetry and Argo profiling floats

Multibeam echosounder systems (MBES) have long provided bathymetric data with high temporal and spatial resolution. In the last couple of decades, MBES observations of scattering in the water column have been finding increasing use in oceanographic studies. Here we review the wealth of studies using water column multibeam data to address questions in fisheries, marine mammal and zooplankton research as well as seeps and hydrothermal vents. We also summarize some of the tantalizing new oceanographic applications of water column MBES, such as kelp ecosystems, near surface bubbles, suspended sediment, mixing and internal waves, as well as the proper determination of the extent of shipwreck above the sea floor. We highlight the many advantages of using water column MBES and discuss the challenges.

A Review of Oceanographic Applications of Water Column Data from Multibeam Echosounders

The accuracies of the meteorological sensors (air temperature, relative humidity, barometric pressure, near-surface temperature, longwave and shortwave radiation, and wind speed and direction) that compose the Improved Meteorological (IMET) system used on buoys at long-term ocean time series sites known as ocean reference stations (ORS) are analyzed to determine their absolute error characteristics The predicted errors are compared to in situ measurement discrepancies and other observations (direct flux shipboard sensors) to confirm the predictions The meteorological errors are then propagated through bulk flux formulas and the Coupled Ocean–Atmosphere Response Experiment (COARE) algorithm to give predicted errors for the heat flux components, the freshwater flux, and the momentum flux Absolute errors are presented for three frequency bands [instantaneous (1-min sampling), diurnal, and annual] The absolute uncertainty in the annually averaged net heat flux is found to be 8 W m−2 for condition

/pdf/accuracy-of-the-imet-sensor-package-in-the-subtropics-1mhqg8nx6a.pdf

Accuracy of the IMET Sensor Package in the Subtropics

Author Posting. © Sears Foundation for Marine Research, 2007. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 65 (2007): 607-637, doi:10.1357/002224007783649510.

/pdf/the-variability-and-heat-budget-of-the-upper-ocean-under-the-2hrs3z44cu.pdf

Keir Colbo

Papers

A Review of Oceanographic Applications of Water Column Data from Multibeam Echosounders

Accuracy of the IMET Sensor Package in the Subtropics

The variability and heat budget of the upper ocean under the Chile-Peru stratus