Cosmogenic radionuclides, such as ~(10)Be, are commonly used for reconstructing solar activity in the past. The interpretation of ~(10)Be records, most commonly obtained from polar ice cores, is complicated by the mixing of ~(10)Be in the atmosphere, its transport to polar regions and its deposition. Throughout the generations of ~(10)Be studies these complications have been mentioned but never investigated on a physical basis. This manuscript aims to summarize the recent efforts to study the atmospheric transport of ~(10)Be from its production to its deposition into the polar ice using three-dimensional physically based general circulation models (GCMs) of the atmosphere. These models represent our best understanding of the atmospheric processes up to date. The model studies indicate that the most important factor controlling the deposition response of ~(10)Be to production changes is the fact that a major part of it (～65) is produced in the stratosphere where its residence time is long and it undergoes strong mixing. Therefore, in an ideal archive the ~(10)Be concentrations will reflect the global mean production rate and hence changes in the solar activity. An explanation is offered for the partly different deposition responses of ~(10)Be snow concentrations to production changes obtained with two different GCMs.

关键词：大气传输;沉积;气候影响;铍-10

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The influence of gravity waves (GWs) on the distributions of minor chemical constituents in the mesosphere-lower thermosphere (MLT) is studied on the basis of the effective diffusivity concept. The mixing ratios of chemical species used for calculations of the effective diffusivity are obtained from numerical experiments with an off-line coupled model of the dynamics and chemistry abbreviated as KMCM-MECTM (Kuehlungsborn Mechanistic general Circulation Model—MEsospheric Chemistry-Transport Model). In our control simulation the MECTM is driven with the full dynamical fields from an annual cycle simulation with the KMCM, where mid-frequency GWs down to horizontal wavelengths of 350 km are resolved and their wave-mean flow interaction is self-consistently induced by an advanced turbulence model. A perturbation simulation with the MECTM is defined by eliminating all meso-scale variations with horizontal wavelengths shorter than 1000 km from the dynamical fields by means of spectral filtering before running the MECTM. The response of the MECTM to GWs perturbations reveals strong effects on the minor chemical constituents. We show by theoretical arguments and numerical diagnostics that GWs have direct, down-gradient mixing effects on all long-lived minor chemical species that possess a mean vertical gradient in the MLT. Introducing the term wave diffusion (WD) and showing that wave mixing yields approximately the same WD coefficient for different chemical constituents, we argue that it is a useful tool for diagnostic irreversible transport processes. We also present a detailed discussion of the gravity-wave mixing effects on the photochemistry and highlight the consequences for the general circulation of the MLT.

关键词：波扩散;重力波;波混频;有效扩散'大气化学

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The goal of this research has been to improve tropical cyclone intensity prediction through a theoretical study of the hurricane inner core (i.e., within 100-km), the role of ocean structure on hurricane intensity, and the incorporation of those results in a simplified intensity prediction system. The intensity prediction system is being tested in an operational framework in the western North Pacific and is being provided to the Joint Typhoon Warning Center (JTWC) for evaluation. The intensity model is based on the statistical- dynamical logistic growth equation model (LGEM), which has generally been the most accurate operational intensity model in the Atlantic basin during the last several hurricane seasons.

关键词：热带气旋;微分方程;强度;数学模型;预测

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This report describes the activities of the NOAA Chesapeake Bay Office for fiscal year (FY) 2011 and 2012 under the NOAA Authorization Act, 15 U.S.C. 1511d. This report fulfills the Congressional requirement in Sec. 307 (b)(7) for a biennial report on the activities of the Office and on the progress made in protecting and restoring the living resources and habitat of the Chesapeake Bay.

关键词：水产资源;栖息地;保护;报告的要求;水资源

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New Large Aircraft (NLA) pose novel firefighting challenges never previously considered for traditional aircraft. Specifically, questions have arisen regarding the applicability of current firefighting protection standards to non-conventional design changes such as fuselage shape modifications, enhanced material compositions, new fuel storage locations, and unique passenger loading configurations. To address fuselage shape concerns, a computational fluid dynamic (CFD) modeling strategy was developed to quantify heat transfer to the aircraft for a given aircraft geometry and hydrocarbon pool fire condition. CFD predictions support experimental validation data conclusions showing increased crosswinds amplify heat transfer to the aircraft surface due to enhanced turbulent fuel-air mixing. Based upon the predicted CFD fire plume structure and aircraft surface heat transfer magnitudes, nominal changes in aircraft geometry exposed to similar scale flame and atmospheric conditions pose no extraordinary firefighting challenge. However with NLA carrying an excessive amount of fuel compared to traditional aircraft, NLA have the capacity to create a significantly larger accidental fire threat. Unique fire suppression measures must still be taken to ensure the same level of protection at a physically larger scale.

关键词：火灾；航空器；计算流体动力学；雷诺数；大气

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On August 5, 2012, the Mars Science Laboratory entry vehicle successfully entered Mars atmosphere, flying a guided entry until parachute deploy. The Curiosity rover landed safely in Gale crater upon completion of the Entry Descent and Landing sequence. This paper compares the aerodynamics of the entry capsule extracted from onboard flight data, including Inertial Measurement Unit (IMU) accelerometer and rate gyro information, and heatshield surface pressure measurements. From the onboard data, static force and moment data has been extracted. This data is compared to preflight predictions. The information collected by MSL represents the most complete set of information collected during Mars entry to date. It allows the separation of aerodynamic performance from atmospheric conditions. The comparisons show the MSL aerodynamic characteristics have been identified and resolved to an accuracy better than the aerodynamic database uncertainties used in preflight simulations. A number of small anomalies have been identified and are discussed. This data will help revise aerodynamic databases for future missions and will guide computational fluid dynamics (CFD) development to improved prediction codes.

关键词：气动特性;大气;火星大气;压力测量;热屏蔽

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In this effort was developed a high temperature 1-D solver to reconstruct the Longshot wind tunnel conditions. It supports calorically imperfect, thermally perfect flows in thermal equilibrium or non-equilibrium.

关键词：飞行器；校准；热值；能量转移；嵌入式大气数据系统

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In a previous paper Judt and Chen propose that secondary eyewall formation can be the result of the accumulation of convectively generated potential vorticity in the rainbands. They argue that secondary potential vorticity maxima precede the development of the secondary wind maximum and conclude that vortex Rossby waves do not contribute to the formation of the secondary eyewall. Amidst examination of their thought-provoking study, some questions arose regarding their methodology, interpretation, and portrayal of previous literature. Here the authors inquire about aspects of the methodology for diagnosing vortex Rossby waves and assessing their impact on their simulation. Inaccuracies in the literature review are noted and further analysis of existing, three-dimensional, full-physics, numerical hurricane integrations that exhibit canonical secondary eyewalls are encouraged.

关键词：对流（大气）；飓风；雨；风；涡；雨带

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This report presents a set of functions, written in C++, that can be used to calculate atmospheric conditions (temperature, pressure, air density, and speed of sound), as well as gravitational-field strength. The functions are based on the atmospheric model presented in U.S. Standard Atmosphere, 1976 (National Aeronautics and Space Administration. U.S. Standard Atmosphere, 1976; NASA-TM-X-74335; U.S. Government Printing Office: Washington, DC, October 1976).

关键词：大气模型；密度；比重；压力；声音；温度；空气密度

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Environmental quality and climate change are major challenges facing our nation and the worldwith current and potential impacts in the near and distant future. Fundamental understanding of atmospheric processes and coupling between the atmosphere, oceans, and biosphere are needed to understand and predict the interactions between climate and environmental processes and energy production practices. This is critical for providing policy makers with accurate information needed to develop cost-effective strategies to monitor, control, mitigate, and adapt to a changing climate. Reducing uncertainties in key components necessary to understand the Earth's complex climate and environmental systems is an important scientific objective, as discussed in National Research Council and National Science Foundation reports and embraced by the Climate and Environmental Sciences Division (CESD) within the Department of Energy's Office of Biological and Environmental Research (DOE-BER). The Environmental Molecular Sciences Laboratory (EMSL), a DOE scientific user facility located in Richland, Washington, encourages and enables molecular-level research that leads to discovery and innovation which enhances the quality of life, now and for generations to come. Because of the growing recognition of atmospheric aerosol chemistry impacts on climate change, regional pollution, and weather patterns, EMSL conducted a Science Theme Advisory Panel (STAP) workshop focused on atmospheric aerosol chemistry. Thirty-eight scientists from 11 institutions participated in the workshop held on January 30, 2013. Workshop participants were asked to evaluate areas where understanding the chemical details and time evolution of aerosol formation and development, as well as their chemical and physical properties, could have the largest impact on the development of reliable process-level understanding of regional and global atmospheric climate models.

关键词：大气化学；气溶胶；气候变化；空气质量；空气污染

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