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Improving our ability to predict future weather and climate conditions is strongly linked to achieving significant advancements in our understanding of cloud and precipitation processes. Observations are critical to making these advancements because they both improve our understanding of these processes and provide constraints on numerical models. Historically, instruments for observing cloud properties have limited cloud–aerosol investigations to a small subset of cloud-process interactions. To address these challenges, the last decade has seen the U.S. DOE ARM facility significantly upgrade and expand its surveillance radar capabilities toward providing holistic and multiscale observations of clouds and precipitation. These upgrades include radars that operate at four frequency bands covering a wide range of scattering regimes, improving upon the information contained in earlier ARM observations. The traditional ARM emphasis on the vertical column is maintained, providing more comprehensive, calibrated, and multiparametric measurements of clouds and precipitation. In addition, the ARM radar network now features multiple scanning dual-polarization Doppler radars to exploit polarimetric and multi-Doppler capabilities that provide a wealth of information on storm microphysics and dynamics under a wide range of conditions. Although the diversity in wavelengths and detection capabilities are unprecedented, there is still considerable work ahead before the full potential of these radar advancements is realized. This includes synergy with other observations, improved forward and inverse modeling methods, and well-designed data–model integration methods. The overarching goal is to provide a comprehensive characterization of a complete volume of the cloudy atmosphere and to act as a natural laboratory for the study of cloud processes.

We present an overview of key aspects of the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) data quality assurance program. Processes described include instrument deployment and calibration; instrument and facility maintenance; data collection and processing infrastructure; data stream inspection and assessment; problem reporting, review and resolution; data archival, display and distribution; data stream reprocessing; engineering and operations management; and the roles of value-added data processing and targeted field campaigns in specifying data quality and characterizing field measurements. The paper also includes a discussion of recent directions in ACRF data quality assurance. A comprehensive, end-to-end data quality assurance program is essential for producing a high-quality data set from measurements made by automated weather and climate networks. The processes developed during the ARM Program offer a possible framework for use by other instrumentation- and geographically-diverse data collection networks and highlight the myriad aspects that go into producing research-quality data.

The Mixed-Phase Arctic Cloud Experiment (M-PACE) was conducted September 27 through October 22, 2004 on the North Slope of Alaska. The primary objective was to collect a data set suitable to study interactions between microphysics, dynamics and radiative transfer in mixed-phase Arctic clouds. Observations taken during the 1997/1998 Surface Heat and Energy Budget of the Arctic (SHEBA) experiment revealed that Arctic clouds frequently consist of one (or more) liquid layers precipitating ice. M-PACE sought to investigate the physical processes of these clouds utilizing two aircraft (an in situ aircraft to characterize the microphysical properties of the clouds and a remote sensing aircraft to constraint the upwelling radiation) over the Department of Energy s Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) on the North Slope of Alaska. The measurements successfully documented the microphysical structure of Arctic mixed-phase clouds, with multiple in situ profiles collected in both single-layer and multi-layer clouds over two ground-based remote sensing sites. Liquid was found in clouds with temperatures down to -30 C, the coldest cloud top temperature below -40 C sampled by the aircraft. Remote sensing instruments suggest that ice was present in low concentrations, mostly concentrated in precipitation shafts, although there are indications of light ice precipitation present below the optically thick single-layer clouds. The prevalence of liquid down to these low temperatures could potentially be explained by the relatively low measured ice nuclei concentrations.

The interaction of clouds and radiation is a particularly difficult issue in the study of climate change. Clouds have a large impact on the earth's radiation budget but the range of spatial and temporal scales and the complexity of the physical processes associated with clouds made these interactions difficult to simulate. The Department of Energy's Atmospheric Radiation Measurement (ARM) program was established to improve the understanding of the interaction of radiation with the atmosphere with a particular emphasis on the effects of clouds. To continue its role of providing data for the study of these interactions, the ARM program deployed an Atmospheric Radiation and Cloud Station (ARCS) in the tropical western Pacific. This site began operation in October 1996. The tropical western Pacific is a very important climatic region. It is characterized by strong solar heating, high water vapor concentrations, and active convection. The ARCS is equipped with a comprehensive suite of instruments for ...

The Radiatively Important Parameters Best Estimate (RIPBE) VAP was developed to create a complete set of clearly identified set of parameters on a uniform vertical and temporal grid to use as input to a radiative transfer model. One of the main drivers for RIPBE was as input to the Broadband Heating Rate Profile (BBHRP) VAP, but we also envision using RIPBE files for user-run radiative transfer codes, as part of cloud/aerosol retrieval testbeds, and as input to averaged datastreams for model evaluation.

This white paper provides a plan to formalize the evaluation of newly developed VAPs and a framework for the development of value-added products through four different stages: Initiation, Development, Evaluation, and Release.

The uncertainties in current estimates of anthropogenic radiative forcing are dominated by the effects of aerosols, both in relation to the direct absorption and scattering of radiation by aerosols and also with respect to aerosol-related changes in cloud formation, longevity, and microphysics (See Figure 1; Intergovernmental Panel on Climate Change, Assessment Report 4, 2008). Moreover, the Arctic region in particular is especially sensitive to changes in climate with the magnitude of temperature changes (both observed and predicted) being several times larger than global averages (Kaufman et al. 2009). Recent studies confirm that aerosol-cloud interactions in the arctic generate climatologically significant radiative effects equivalent in magnitude to that of green house gases (Lubin and Vogelmann 2006, 2007). The aerosol optical depth is the most immediate representation of the aerosol direct effect and is also important for consideration of aerosol-cloud interactions, and thus this quantity is essential for studies of aerosol radiative forcing.

Clouds represent a critical component of the Earth’s atmospheric energy balance as a result of their interactions with solar and terrestrial radiation and a redistribution of heat through convective processes and latent heating. Despite their importance, clouds and the processes that control their development, evolution and lifecycle remain poorly understood. Consequently, the simulation of clouds and their associated feedbacks is a primary source of inter-model differences in equilibrium climate sensitivity. An important step in improving the representation of cloud process simulations is an improved high-resolution observational data set of the cloud systems including their time evolution. The first order quantity needed to understand the important role of clouds is the height of cloud occurrence and how it changes as a function of time. To this end, the Atmospheric Radiation Measurement (ARM) Climate Research Facilities (ACRF) suite of instrumentation has been developed to make the observations required to improve the representation of cloud systems in atmospheric models.

In 2008, the Atmospheric Radiation Measurement (ARM) Program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties.

This report documents key aspects of the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) data quality assurance program as it existed in 2008. The performance of ACRF instruments, sites, and data systems is measured in terms of the availability, usability, and accessibility of the data to a user. First, the data must be available to users; that is, the data must be collected by instrument systems, processed, and delivered to a central repository in a timely manner. Second, the data must be usable; that is, the data must be inspected and deemed of sufficient quality for scientific research purposes, and data users must be able to readily tell where there are known problems in the data. Finally, the data must be accessible; that is, data users must be able to easily find, obtain, and work with the data from the central repository. The processes described in this report include instrument deployment and calibration; instrument and facility maintenance; data collection and processing infrastructure; data stream inspection and assessment; the roles of value-added data processing and field campaigns in specifying data quality and haracterizing the basic measurement; data archival, display, and distribution; data stream reprocessing; and engineering and operations management processes and procedures. Future directions in ACRF data quality assurance also are presented.

[1] Computation of components of shortwave (SW) or solar irradiance in the surface-atmospheric system forms the basis of intercomparison between 16 radiative transfer models of varying spectral resolution ranging from line-by-line models to broadband and general circulation models. In order of increasing complexity the components are: direct solar irradiance at the surface, diffuse irradiance at the surface, diffuse upward flux at the surface, and diffuse upward flux at the top of the atmosphere. These components allow computation of the atmospheric absorptance. Four cases are considered from pure molecular atmospheres to atmospheres with aerosols and atmosphere with a simple uniform cloud. The molecular and aerosol cases allow comparison of aerosol forcing calculation among models. A cloud-free case with measured atmospheric and aerosol properties and measured shortwave radiation components provides an absolute basis for evaluating the models. For the aerosol-free and cloud-free dry atmospheres, models agree to within 1% (root mean square deviation as a percentage of mean) in broadband direct solar irradiance at surface; the agreement is relatively poor at 5% for a humid atmosphere. A comparison of atmospheric absorptance, computed from components of SW radiation, shows that agreement among models is understandably much worse at 3% and 10% for dry and humid atmospheres, respectively. Inclusion of aerosols generally makes the agreement among models worse than when no aerosols are present, with some exceptions. Modeled diffuse surface irradiance is higher than measurements for all models for the same model inputs. Inclusion of an optically thick low-cloud in a tropical atmosphere, a stringent test for multiple scattering calculations, produces, in general, better agreement among models for a low solar zenith angle (SZA = 30°) than for a high SZA (75°). All models show about a 30% increase in broadband absorptance for 30° SZA relative to the clear-sky case and almost no enhancement in absorptance for a higher SZA of 75°, possibly due to water vapor line saturation in the atmosphere above the cloud.

The records of 34 patients who showed evidence of emotional deterioration 6 months or more following traumatic brain injury were compared with a group of patients matched for severity of initial neuropsychiatric impairment who did not show deterioration. The deterioration group was more likely to have been involved in assaults and less likely to have been involved in a motor vehicle accident than the improvement group. The deterioration group was also more likely to have a prior history of alcohol abuse and to have sustained a skull fracture with left parietal lobe injury than the improvement group. Agitation, hostility, apathy, lability of mood, emotional withdrawal, and depression were the symptoms most likely to worsen over time. This deterioration may have been due to premorbid personality characteristics or to the nature of long-term neuronal response to injury.

Most radiologists must have been puzzled at some time or other, when examining radiograms of the chest, by the occasional finding of a fine convex line which begins at the right apex and curves downwards and inwards towards the mediastinum, to end just below the level of the costal cartilage of the first rib in a dense comma-shaped shadow. The situation of both the line and the comma-shaped shadow is, however, subject to wide variation. In some cases the line is quite near to the mediastinum, in others much further out and the comma-shaped shadow may be as low as the level of the costal cartilage of the second rib. (Figs. 1 and 2.) One of us (J.H.M.) when reporting, has drawn the attention of his physician colleagues to this shadow, without hitherto being able to offer any adequate explanation of its presence. In July of this year, Bendick and Wessler (1928) described and interpreted this shadow, and pointed out how few are the references to it in Rontgenological literature. Wessler and J aches had descri...

The first case of Progressive Myositis Ossificans was reported in 1692 by Patin.1 Since then 149 cases have been recorded. Rosenstirn2 in a comprehensive paper, in which he analysed the first 115 cases recorded, states that the characteristic features of this disease are:— (1) Ossification of muscles without any apparent cause; (2) The manifestation of the disease as a congenital one or appearing in early life; (3) The progressive course of the malady embracing in advanced cases nearly the whole of the voluntary muscular system; (4) The association with symptoms of defective anatomical and physiological formation, mostly of the fingers and toes, but not infrequently also of stature, habitus and sex differentiation.

Although cases of multiple cysts of the lungs are said not to be uncommon in certain parts of the world, they are certainly rarely seen in this country and I therefore thought the following case worth reconding. E.W., a male age 18½, was sent to me on May 5, 1927, for a radiological examination of the chest, a provisional diagnosis of phthisis having been made. His occupation was that of clerk and he lived at home.

Although polyvinylidene fluoride (PVDF) piezoelectric film has been adopted in commercial applications for some time, its use in basic research has been less extensive. Recently, there have been found significant advantages in using PVDF to study the ultrasonic properties of the new high‐temperature oxide superconductors. In order to probe the anisotropy of the oxide superconductors, it is necessary to study single crystals, but currently available crystals are very small, on the order of the millimeter square and only about 100uμm thick. Measuring the temperature dependence of the ultrasound in such a small sample without having the transducer (or its leads or substrate) intrude on the measurement is a difficult problem that is not readily solved with conventional transducer materials. However, PVDF films as thin as 9 μm are commercially available and easily adapted to small samples and low‐temperature operation. Small active areas and leads are produced with metalization patterns on each side of the PVDF film. For resonance measurements, electrical crosstalk across the small sample is processed by frequency modulating the drive and using phase sensitive detection. In our experiment, resonances in ≃ 100‐uμm samples are measured with large signal‐to‐noise ratios. [Work supported by the Office of Naval Research and NSF Grant DMR 8701682.]

Resonant ultrasound measurements in very pure single crystals of La2CuO4 have been made. The material was prepared such that its resistivity at 300 K is extremely high (170 Ω cm), and untwinned crystals of about 0.1×0.1×0.1 cm were used. Oxygen was then introduced, eventually leading to superconductivity. Here, data on the three longitudinal sound velocities and attenuations as a function of temperature for different oxygen dopings are presented and the effects of magnetic and superconducting interactions are discussed. All data were taken with a resonant ultrasound method developed by us in which the transducers are flexible and are less than 1% of the sample mass, minimizing transducer loading effects.