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Yonghong Yi, John S. Kimball, Lucas A. Jones, Rolf H. Reichle, and Kyle C. McDonald

soil moisture variability over longer (e.g., monthly to seasonal) time scales. Therefore, retrievals from ascending and descending overpasses were combined on a gridcell-by-gridcell basis for each product to improve global daily coverage. Soil moisture retrievals at 6.9-GHz frequency were used exclusively except where strong 6.9-GHz RFI was detected ( Njoku et al. 2005 ); these areas included the contiguous United States (CONUS), Japan, and some areas in the Middle East and India, whereby soil

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Franklin R. Robertson and Jason B. Roberts

compared to MODIS. This tends to weaken the TOA net SW CRE. But the early growth of MERRA high plus middle clouds into a cold atmosphere ( Fig. 4 ) means that the LW CRE peaks earlier than is seen in SRB. These two offsetting factors contribute to the agreement in net TOA flux between MERRA and the GEWEX SRB observations. The net CRE is obviously sensitive not just to the amount of cloudiness present, but also to the height (temperature) and optical properties of the clouds. To assess the intraseasonal

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Siegfried Schubert, Hailan Wang, and Max Suarez

1. Introduction The boreal summer extratropical circulation lacks the strong jets and large-amplitude stationary waves that typify the boreal winter climate. This, together with the presence of pervasive tropical easterlies that inhibit remote forcing from the tropics, tends to limit boreal summer middle-latitude variability to more local/regional processes, with mesoscale convective weather systems and land–atmosphere coupling playing important roles (e.g., Parker and Johnson 2000 ; Koster

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Michael G. Bosilovich, Franklin R. Robertson, and Junye Chen

1. Introduction In the study of the earth’s climate, quantifying global water and energy cycling rates and the associated physical processes more accurately is critical to understanding the climate and its mechanisms of variability and change from global to local scales. The sun heats the atmosphere and the surface, thus driving many processes including the transfer of energy and water and ultimately dynamical transports of these quantities. Trenberth et al. (2009 , hereafter TFK09 ) provide

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Behnjamin J. Zib, Xiquan Dong, Baike Xi, and Aaron Kennedy

1. Introduction Over the past few decades, atmospheric reanalysis datasets have provided a long-term, gridded representation of the state of the atmosphere while offering a resource for investigating climate processes and predictability. Reanalyses utilize observations through state-of-the-art data assimilation systems. Combined with underlying models, they provide a continuous data record that consists of various atmospheric variables describing (diagnosing) past weather conditions. Reanalyses

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Tiffany A. Shaw, Judith Perlwitz, Nili Harnik, Paul A. Newman, and Steven Pawson

. (2011) suggested that ozone depletion was the likely cause of the changes. Our results clearly attribute the change in downward wave coupling in the GEOS model to ozone changes and suggest that, as ozone recovers during the twenty-first century, downward wave coupling during November–December is expected to decrease. In a recent study, McLandress et al. (2010) used a series of Canadian Middle Atmosphere Model (CMAM) simulations with and without chlorine changes to investigate the separate impacts

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J. Brent Roberts, Franklin R. Robertson, Carol A. Clayson, and Michael G. Bosilovich

1. Introduction The oceans provide a vast repository of both heat and water that are of critical importance to the earth’s hydrologic and energy cycles. Because of their inherent high heat capacity relative to the atmosphere, the global oceans integrate energy exchanges across the atmospheric interface, providing both “memory” of past fluxes and a potential source of predictability for the atmosphere. These exchanges of moisture and heat with the atmosphere vary richly on a wide range of space

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Sun Wong, Eric J. Fetzer, Brian H. Kahn, Baijun Tian, Bjorn H. Lambrigtsen, and Hengchun Ye

( u , υ , ω ) are the horizontal and vertical wind velocities, respectively; and S is referred to as the apparent water vapor sink in the literature ( Schumacher et al. 2008 ; Shige et al. 2008 ; Yanai et al. 1973 ) and differs from the conventional defined Q2 in the literature by a factor equal to the water latent heat of evaporation ( L ). The integrated S from the top of the atmosphere ( p t ) to the surface pressure ( p s ) (denoted as Σ) is approximately equal to P − E at the

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Michele M. Rienecker, Max J. Suarez, Ronald Gelaro, Ricardo Todling, Julio Bacmeister, Emily Liu, Michael G. Bosilovich, Siegfried D. Schubert, Lawrence Takacs, Gi-Kong Kim, Stephen Bloom, Junye Chen, Douglas Collins, Austin Conaty, Arlindo da Silva, Wei Gu, Joanna Joiner, Randal D. Koster, Robert Lucchesi, Andrea Molod, Tommy Owens, Steven Pawson, Philip Pegion, Christopher R. Redder, Rolf Reichle, Franklin R. Robertson, Albert G. Ruddick, Meta Sienkiewicz, and Jack Woollen

[which peaks at a similar level, about 1.5 hPa ( Kobayashi et al. 2009 )]. However, biases of up to 5 K are still evident at 1 hPa and above. Fig . 5. Mean temperature profiles (K) from MLS and collocated MERRA profiles over the globe for August 2008. Comparisons (left) when VBC is applied to AMSU-A channel 14 and (middle) when VBC is omitted, and (right) the differences between the mean profiles for each case. Just as variational bias correction has provided significant benefit to the assimilation

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Brian E. Mapes and Julio T. Bacmeister

1. Introduction There are many ways to learn from the confrontation of an atmosphere model with observations, in service of model improvement. The study of initial tendencies [or errors in one-time-step forecasts, Klinker and Sardeshmukh (1992) ] is appealing because the effect of a model process error is localized. However, initialization shock may dominate the results, making interpretation subtle (e.g., Judd et al. 2008 ). At the other extreme of time scale, the biases of unconstrained

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