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Jesse O. Bash and David R. Miller

systems. Anthropogenic activity has enriched this natural cycle through the combustion of coal and oil for power, the production of chemicals, and the incineration of waste ( Pirrone et al. 2001 ). The contribution of biogenic and physiochemical mercury emissions from land and water surfaces to the total atmospheric mercury load have recently been estimated to be roughly equivalent to anthropogenic emissions ( Pirrone et al. 2001 ; Lindberg et al. 1998 ). The origins of this spatially distributed Hg

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R. J. Sica, Z. A. Zylawy, and P. S. Argall

assuming hydrostatic equilibrium and using the Ideal Gas law. This method has been described in detail by Hauchcorne and Chanin (1980) for an ozone-free atmosphere and expanded on by Keckhut et al (1993) . Leblanc et al. (1998) have simulated this method in detail and present estimates of the accuracy of the retrieval. Their analysis includes (among other effects) ozone absorption and mentions both the necessity of a correction and that the correction is not strongly dependent on the choice of

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Igor Podgorny, Dan Lubin, and Donald K. Perovich

program at Palmer Station, Antarctica ( Lubin et al. 2002 ; McComiskey et al. 2006 ). In this study, we consider how 3D radiative transfer effects might affect UAV-based radiation measurements. As in Podgorny and Lubin (1998) , we consider simplified cloud geometry and spatial variability over a horizontally inhomogeneous surface. When comparing the theoretical MC results of Podgorny and Lubin (1998) with Antarctic field data ( Lubin et al. 2002 ; McComiskey et al. 2006 ), we found that the

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James W. Hannigan, Michael T. Coffey, and Aaron Goldman

is attributed to the decrease in anthropogenic production of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) countered by the long lifetime of the predominant CFC, CCl 2 F 2 . These measurements at a remote high-latitude site show a slow but significant continued buildup of HF and effectively no rate of change of CCl 2 F 2 . Both HCl and ClONO 2 become chemically activated in the polar stratospheric vortex during winter and spring ( Coffey et al. 1999 ; WMO 2006 ). Total columns

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R. E. M. Neubert, L. L. Spijkervet, J. K. Schut, H. A. Been, and H. A. J. Meijer

1. Introduction Sampling of atmospheric whole air into glass flasks for later laboratory analysis of trace gas concentrations and isotopic ratios (commonly known as flask sampling) has proven to be a tool of major importance in global carbon cycle research (e.g., Conway et al. 1994 ; Keeling et al. 1995 ; Francey et al. 1995 ). In this way, air samples can be taken even at remote places with little infrastructure (and thus anthropogenic influences), providing better observation coverage of

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Andreas F. Hofmann, Peter M. Walz, Hans Thomas, Edward T. Peltzer, and Peter G. Brewer

limit very close to oxygen conditions established at the sill depth of the basin [ Childress and Seibel 1998 , and Monterey Bay Aquarium Research Institute (MBARI) remotely operated vehicle (ROV) observations]. The decomposition of anthropogenic organic waste discharged into the ocean can cause or exacerbate hypoxic conditions. Horizontal gradients in oxygenation of the flat parts of the basin bottom (i.e., not related to water depth) might indicate point-source-driven oxygen drawdown processes

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Hongbo Liu, Janina V. Büscher, Kevin Köser, Jens Greinert, Hong Song, Ying Chen, and Timm Schoening

the Tisler Reef in Norway during the R/V Poseidon cruise POS526 ( Greinert and Schoening 2019 ). (b) A close-up photograph of a branch of white Lophelia pertusa whose polyps and skeletons are similar in color. Today, Lophelia pertusa bioherms suffer from anthropogenic threats. Direct impacts of human activities include physical damage by bottom trawling, exposure to sediment resuspension (caused by trawls or anchors), and discharge of sediments and minerals from hydrocarbon drilling and

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Pinar Kus, Christian M. Carrico, Mark J. Rood, and Allen Williams

1. Introduction Investigation of the effects of aerosols on atmospheric radiative transfer and hence visibility and climate relies on a range of techniques for measuring and modeling aerosol optical properties. The integrating nephelometer, an instrument that can measure total and back light scattering coefficients by aerosol particles ( σ sp and σ bsp , respectively), has been developed, commercialized, and used for visual air quality studies over many decades ( Charlson et al. 1969

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Fernando J. Méndez, Melisa Menéndez, Alberto Luceño, and Inigo J. Losada

levels (e.g., Woodworth et al. 1999 ; Flick et al. 2003 ; Pugh 2004 , chapter 7). This aspect is well known and has been widely studied by the scientific community because of the potential effects on coastal areas ( Houghton et al. 2001 ). Lately, there is some evidence around the globe that suggests that not only sea level rise but also long-term changes in the intensity and frequency of the storminess must be considered (e.g., Meehl et al. 2000 ; Woodworth and Blackman 2004 ; Bijl et al. 1999

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Koji Nishimura, Takuji Nakamura, Toru Sato, and Kaoru Sato

reception beams In this section, we describe the concept and algorithm of NC-DCMP, which is the norm-constrained variation of the original DCMP, and its asymptotic properties in terms of its effects on the effective echo pattern. The principle of NC-DCMP is to find a complex weight vector w for multichannel signals r such that the average output power P = 〈| w H r | 2 〉 is minimized, under constant-gain and norm constraints regulating the sensitivity toward the desired direction and upper bounds

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