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Matthew L. Aitken, Michael E. Rhodes, and Julie K. Lundquist

effects of each are examined using the two datasets described in the following section; observations are presented in section 4 . 3. Data and methods A Windcube lidar was deployed in late summer 2010 as part of the Skywatch Observatory—a set of meteorological instruments on the roof (approximately 15 m AGL) of the Duane Physics building at the University of Colorado at Boulder, elevation 1663 m. Backscatter was measured at a vertical resolution of 10 m from ground level to 7690 m AGL using a Vaisala

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Maria Raffaella Vuolo, Laurent Menut, and Hélène Chepfer

atmospheric pollution in Europe’s large urbanized areas where it is added to local anthropogenic pollutants. Model estimates of the aerosol budget over Europe ( Bessagnet et al. 2005 ; Vautard et al. 2005 ) show that 30%–50% of the ≤10- μ m particulate matter (PM10) is not well predicted: mineral dust may be part of the missing source. To get a better estimation of the amount of dust deposited in Europe, it is necessary to reduce model errors from the emission to the surface concentrations as much as

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Hans Richner and Pierre Viatte

computed from pressure and virtual temperature by resortof the hydrostatic equation. Errors in the primary variables affect the accuracy of height data depending on howthe integration of the hydrostatic equation is carried out. Based on simulated ascents in a standard atmosphere,the effects of pressure and temperature errors on the accuracy of height data are for three different integrationschemes. Actual data from an intercomparison flight are also used to demonstrate that the effects of differencesin

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J. Zeng, Y. Nojiri, P. Landschützer, M. Telszewski, and S. Nakaoka

1. Introduction It has been estimated that the global ocean absorbs nearly half the total emissions of anthropogenic carbon dioxide (CO 2 ) from the atmosphere ( Sabine et al. 2004 ; Jacobson et al. 2007 ; Gruber et al. 2009 ; Takahashi et al. 2009 ). The surface ocean shows much more CO 2 variability spatially than the atmosphere, as is shown in Komhyr et al. (1985) and Takahashi et al. (2009) ; hence, it is import to accurately quantify the oceanic CO 2 distribution in order to

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Christopher Sabine, Adrienne Sutton, Kelly McCabe, Noah Lawrence-Slavas, Simone Alin, Richard Feely, Richard Jenkins, Stacy Maenner, Christian Meinig, Jesse Thomas, Erik van Ooijen, Abe Passmore, and Bronte Tilbrook

rate as the atmospheric CO 2 concentrations ( Bates et al. 2014 ; Landschützer et al. 2014 ; Takahashi et al. 2009 ; Wanninkhof et al. 2013a ). The oceanic removal of CO 2 from the atmosphere is reducing the effects of climate change but in turn it is acidifying surface seawater. The ocean removes carbon from the atmosphere via gas equilibration and moves it into the ocean interior at deep and intermediate water formation regions, in a process known as the solubility pump. Atmospheric carbon

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Anna P. M. Michel, David J. Miller, Kang Sun, Lei Tao, Levi Stanton, and Mark A. Zondlo

1. Introduction Atmospheric methane (CH 4 ) is a potent greenhouse gas that is directly responsible for approximately 21% of the total anthropogenic radiative forcing since preindustrial times and has a global warming potential 28 times that of carbon dioxide (CO 2 ) over a 100-yr time horizon ( IPCC 2013 ; Montzka et al. 2011 ). Methane also contributes to tropospheric ozone formation and impacts air quality ( Isaksen et al. 2011 ). Global annual mean CH 4 mixing ratios have been increasing

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J. Marshall Shepherd, Olayiwola O. Taylor, and Carlos Garza

differences in surface albedo and anthropogenic heat release in the urban area. As sensible heat is transferred to the air, the air temperature in urban areas tends to be 2°–10°C higher than surrounding nonurban areas. Figure 1 illustrates the UHI signature of the city of Atlanta, Georgia, using infrared imagery captured by the airborne Advanced Thermal and Land Application System (ATLAS) on 11 and 12 May 1997. The literature indicates that the signature of the “urban heat island effect” may be

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B. B. Murphey and S. I. Reynolds

and the energy gained, as well as the properties of the surface, will determine whether the neteffects of the aerosol is one of cooling or heating. Thesetheoretical concepts have been verified by photometricand calorimetric in situ measurements by Hanel et at.(1982), which have indicated that subs~ntial increasesin ambient temperatures occur as a result of the absorption of shortwave radiation by particles, especiallyin industrial regions. The radiative effects of anthropogenic components in the

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Björn Fiedler, Peer Fietzek, Nuno Vieira, Péricles Silva, Henry C. Bittig, and Arne Körtzinger

( Pfeil et al. 2012 ). Despite the growing database, the present global uptake rate of the World Ocean for anthropogenic CO 2 still has an uncertainty of 50% (+2.0 ±1.0 Pg C yr −1 ; Takahashi et al. 2009 ), which to a major extent is due to limited temporal and spatial coverage of large parts of the oceans, for example, the Southern Ocean. Dissolved CO 2 in the ocean is not only influenced by physical processes (e.g., warming/cooling, mixing) but also by biological processes (e.g., photosynthesis

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P. Campuzano-Jost, C. D. Clark, H. Maring, D. S. Covert, S. Howell, V. Kapustin, K. A. Clarke, E. S. Saltzman, and A. J. Hynes

1. Introduction It is clear that attempts to better understand and quantify both the direct and indirect forcing effects of atmospheric aerosols have changed our view of their role in climate change ( Prospero 2002 ). While many early studies focused exclusively on sulfate aerosols ( Charlson et al. 1992 ), it is now clear that sea salt, mineral dust, and organic aerosols play a significant effect in direct scattering of solar radiation ( Pilinis et al. 1995 ; Satheesh et al. 1999 ). Initial

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