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M. Portabella and A. Stoffelen

1. Introduction Wind forces motion in the ocean and in turn the motion in the ocean determines the weather and climate in large portions of the world. Wind forcing is essential in El Niño–Southern Oscillation (ENSO) and other ocean–atmosphere interaction phenomena occurring in the tropics. As such, a homogeneous wind dataset of high quality would much advance research on the prediction and mechanisms of seasonal forecasting. Vialard (2000) emphasizes that wind stress is certainly the most

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Falk Feddersen and A. J. Williams III

1. Introduction The Reynolds stress terms and , where u ′, v ′, and w ′, respectively, represent the cross-shore, alongshore, and vertical components of turbulent velocities and the overbar is an averaging operator, play an important role in the mean momentum and turbulence dynamics of boundary layer flows. Estimating the Reynolds stress from observations is crucial in diagnosing these dynamics. Often the Reynolds decomposition between mean and turbulent velocity components and its

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David K. Hutchinson, Andrew Mc C. Hogg, and Jeffrey R. Blundell

1. Introduction Scatterometer observations of wind stress at the ocean’s surface show clear evidence of both large-scale atmospheric features and smaller-scale features resulting from interactions with the ocean ( Chelton et al. 2004 ). The small-scale oceanic features are caused by two primary mechanisms. The first mechanism is that of the ocean velocity, since stress can be approximated as a quadratic function of the relative velocity between the atmosphere and ocean ( Pacanowski 1987 ). The

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Mikitoshi Hirabara, Hiroshi Ishizaki, and Ichiro Ishikawa

1. Introduction Recent studies about global warming or multidecadal variability in the climate system indicate a poleward shift or long-term oscillation of the westerly wind over the Southern Ocean (e.g., Cai et al. 2003 ). The responses in the ocean to changes in wind stress over the Southern Ocean were investigated in previous studies (e.g., Oke and England 2004 ). In the latitude band containing the Drake Passage, meridional geostrophic flow zonally integrated above the sill depth must be

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Richard T. McNider, John R. Christy, Don Moss, Kevin Doty, Cameron Handyside, Ashutosh Limaye, Axel Garcia y Garcia, and Gerrit Hoogenboom

drought, failed to respond quickly to drought stress on crops that were primarily responding to moisture sometimes in the first few inches of top soil. Palmer (1968) developed a shorter-term index called the crop moisture index (CMI). While the PDSI and CMI can accept higher-resolution inputs, they have primarily been driven by the National Weather Service (NWS) Cooperative Observer Program coarse-resolution data for rainfall and soil characteristics and retained the simplified evaporative loss

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Tsuyoshi Wakamatsu, Michael G. G. Foreman, Patrick F. Cummins, and Josef Y. Cherniawsky

optimal sizes of errors are sought by minimizing a cost function that requires knowledge of the statistical properties of those errors. Generally, estimating an adequate structure for the statistical properties is not a trivial task and we need to model them with certain assumptions. In this study, we investigate the impact of the assumptions we make for the wind stress error covariance function in estimating wind-driven basin-scale ocean circulation. The statistical properties of the wind stress

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Craig M. Risien and Dudley B. Chelton

for June, July, and August (JJA) from 46 yr of International Comprehensive Ocean–Atmosphere Dataset (ICOADS) release 2.1 ( Worley et al. 2005 ). These ship-based observations are heavily biased in favor of the Northern Hemisphere and along major shipping routes. This is particularly true for the austral winter months (JJA) when the sampling of the Southern Ocean is reduced to almost zero. HR presented the first ship-based monthly climatology of wind stress and wind stress curl fields on a global

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A. Birol Kara, Alan J. Wallcraft, E. Joseph Metzger, Harley E. Hurlburt, and Chris W. Fairall

1. Introduction and motivation The momentum exchange between the atmosphere and ocean through wind stress is of importance for many purposes, including air–sea interaction studies, climate studies, ocean modeling, and ocean prediction. Wind stress is typically obtained from bulk parameterizations that estimate turbulent fluxes using standard meteorological data (e.g., Fairall et al. 2003 ). In particular, the total wind stress magnitude ( τ ) at the ocean surface can be calculated from the

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Urša Ciuha, Tjaša Pogačar, Lučka Kajfež Bogataj, Mitja Gliha, Lars Nybo, Andreas D. Flouris, and Igor B. Mekjavic

under heat stress, 35% of workers experience occupational heat strain, while 30% of workers report productivity losses ( Flouris et al. 2018a ). However, occupational heat stress has been mainly studied to date in jobs associated with the military, construction, mining, agricultural, and metal industries ( Brake and Bates 2002 ; Hunt et al. 2016 ; Jay and Brotherhood 2016 ; Krishnamurthy et al. 2017 ; Ryan and Euler 2017 ), as they include intense physical activity, wearing of protective

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Xia Lin, Xiaoming Zhai, Zhaomin Wang, and David R. Munday

1. Introduction The Southern Hemisphere (SH) surface westerly wind stress is a major forcing for driving the Antarctic Circumpolar Current (ACC) and upwelling of deep waters in the Southern Ocean (SO). The SH westerly wind stress has strengthened significantly over the last few decades and is projected to continue to do so in the future, which may have important implications for the global climate system via modulating the rate at which the SO uptakes heat and carbon (e.g., Thompson and

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