bluuebunny/crossref_metadata_2025 huggingface dataset:
Assimilation of Simulated Polarimetric Radar Data for a Convective Storm Using the Ensemble Kalman Filter. Part I: Observation Operators for Reflectivity and Polarimetric Variables
Authors: Jung Youngsun , Zhang Guifu , Xue Ming
Published: July 2008

A radar simulator for polarimetric radar variables, including reflectivities at horizontal and vertical polarizations, the differential reflectivity, and the specific differential phase, has been developed. This simulator serves as a test bed for developing and testing forward observation operators of polarimetric radar variables that are needed when directly assimilating these variables into storm-scale numerical weather prediction (NWP) models, using either variational or ensemble-based assimilation methods. The simulator takes as input the results of high-resolution NWP model simulations with ice microphysics and produces simulated polarimetric radar data that may also contain simulated errors. It is developed based on calculations of electromagnetic wave propagation and scattering at the S band of wavelength 10.7 cm in a hydrometeor-containing atmosphere. The T-matrix method is used for the scattering calculation of raindrops and the Rayleigh scattering approximation is applied to snow and hail particles. The polarimetric variables are expressed as functions of the hydrometeor mixing ratios as well as their corresponding drop size distribution parameters and densities. The presence of wet snow and wet hail in the melting layer is accounted for by using a new, relatively simple melting model that defines the water fraction in the melting snow or hail. The effect of varying density due to the melting snow or hail is also included. Vertical cross sections and profiles of the polarimetric variables for a simulated mature multicellular squall-line system and a supercell storm show that polarimetric signatures of the bright band in the stratiform region and those associated with deep convection are well captured by the simulator.
Deep Convection East of the Andes Cordillera: A Test Case Analysis of Airmass Origin
Authors: Teitelbaum Hector , Le Treut Hervé , Moustaoui Mohamed , Cabrera Gustavo C. , Ibañez Guillermo
Published: July 2008

Warm and moist air masses, required to generate deep convection east of the Andes Cordillera, are generally the result of humidity transport by the so-called low-level jet (LLJ). In this paper, it is shown from detailed test cases that the eastern part of the continent and the adjacent Atlantic Ocean may constitute another source of moist, warm air, which could be of potential importance even in the presence of a southerly LLJ. The position of the anticyclones crossing South America from the Pacific Ocean to the Atlantic Ocean appears to be a key factor affecting the origin of moisture over the continent. In particular, the LLJ may weaken and even change its direction when the eastern side of the South Pacific anticyclone crosses the mountains; this wind reversal is generally associated with deep convection suppression. Thus, as a South Pacific anticyclone crosses the continent more to the east and its western side reaches the east coast of South America, deep convection can reappear east of the Andes, over the Mendoza region, although the LLJ is frequently suppressed. This is associated with a transport of warm and moist air from Uruguay, southeast Brazil, or even directly from the Atlantic Ocean.
A Comparison of Two Shallow-Water Models with Nonconforming Adaptive Grids
Authors: St-Cyr Amik , Jablonowski Christiane , Dennis John M. , Tufo Henry M. , Thomas Stephen J.
Published: July 2008

In an effort to study the applicability of adaptive mesh refinement (AMR) techniques to atmospheric models, an interpolation-based spectral element shallow-water model on a cubed-sphere grid is compared to a block-structured finite-volume method in latitude–longitude geometry. Both models utilize a nonconforming adaptation approach that doubles the resolution at fine–coarse mesh interfaces. The underlying AMR libraries are quad-tree based and ensure that neighboring regions can only differ by one refinement level. The models are compared via selected test cases from a standard test suite for the shallow-water equations, and via a barotropic instability test. These tests comprise the passive advection of a cosine bell and slotted cylinder, a steady-state geostrophic flow, a flow over an idealized mountain, a Rossby–Haurwitz wave, and the evolution of a growing barotropic wave. Both static and dynamics adaptations are evaluated, which reveal the strengths and weaknesses of the AMR techniques. Overall, the AMR simulations show that both models successfully place static and dynamic adaptations in local regions without requiring a fine grid in the global domain. The adaptive grids reliably track features of interests without visible distortions or noise at mesh interfaces. Simple threshold adaptation criteria for the geopotential height and the relative vorticity are assessed.
Development and Testing of Polar Weather Research and Forecasting (WRF) Model. Part I: Greenland Ice Sheet Meteorology*
Authors: Hines Keith M. , Bromwich David H.
Published: July 2008

A polar-optimized version of the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) was developed to fill climate and synoptic needs of the polar science community and to achieve an improved regional performance. To continue the goal of enhanced polar mesoscale modeling, polar optimization should now be applied toward the state-of-the-art Weather Research and Forecasting (WRF) Model. Evaluations and optimizations are especially needed for the boundary layer parameterization, cloud physics, snow surface physics, and sea ice treatment. Testing and development work for Polar WRF begins with simulations for ice sheet surface conditions using a Greenland-area domain with 24-km resolution. The winter month December 2002 and the summer month June 2001 are simulated with WRF, version 2.1.1, in a series of 48-h integrations initialized daily at 0000 UTC. The results motivated several improvements to Polar WRF, especially to the Noah land surface model (LSM) and the snowpack treatment. Different physics packages for WRF are evaluated with December 2002 simulations that show variable forecast skill when verified with the automatic weather station observations. The WRF simulation with the combination of the modified Noah LSM, the Mellor–Yamada–Janjić boundary layer parameterization, and the WRF single-moment microphysics produced results that reach or exceed the success standards of a Polar MM5 simulation for December 2002. For summer simulations of June 2001, WRF simulates an improved surface energy balance, and shows forecast skill nearly equal to that of Polar MM5.
The Importance of the Boundary Layer Parameterization in the Prediction of Low-Level Convergence Lines
Authors: Thomsen Gerald L. , Smith Roger K.
Published: July 2008

The importance of the boundary layer parameterization in the numerical prediction of low-level convergence lines over northeastern Australia is investigated. High-resolution simulations of convergence lines observed in one event during the 2002 Gulf Lines Experiment are carried out using the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5). Calculations using five different parameterizations are compared with observations to determine the optimum scheme for capturing these lines. The schemes that give the best agreement with the observations are the three that include a representation of countergradient fluxes and a surface layer scheme based on Monin–Obukhov theory. One of these, the Medium-Range Forecast scheme, is slightly better than the other two, based on its ability to predict the surface pressure distribution. The findings are important for the design of mesoscale forecasting systems for the arid regions of Australia and elsewhere.
Evaluating Rank Histograms Using Decompositions of the Chi-Square Test Statistic
Authors: Jolliffe Ian T. , Primo Cristina
Published: July 2008

Rank histograms are often plotted to evaluate the forecasts produced by an ensemble forecasting system—an ideal rank histogram is “flat” or uniform. It has been noted previously that the obvious test of “flatness,” the well-known χ2 goodness-of-fit test, spreads its power thinly and hence is not good at detecting specific alternatives to flatness, such as bias or over- or underdispersion. Members of the Cramér–von Mises family of tests do much better in this respect. An alternative to using the Cramér–von Mises family is to decompose the χ2 test statistic into components that correspond to specific alternatives. This approach is described in the present paper. It is arguably easier to use and more flexible than the Cramér–von Mises family of tests, and does at least as well as it in detecting alternatives corresponding to bias and over- or underdispersion.
A Perfect Prognosis Scheme for Forecasting Warm-Season Lightning over Florida
Authors: Shafer Phillip E. , Fuelberg Henry E.
Published: July 2008

This study develops and evaluates a statistical scheme for forecasting warm-season lightning over Florida. Four warm seasons of analysis data from the Rapid Update Cycle (RUC) and lightning data from the National Lightning Detection Network are used in a perfect prognosis technique to develop a high-resolution, gridded forecast guidance product for warm-season cloud-to-ground (CG) lightning over Florida. The most important RUC-derived parameters are used to develop equations producing 3-hourly spatial probability forecasts for one or more CG flashes, as well as the probability of exceeding various flash count percentile thresholds. Binary logistic regression is used to develop the equations for one or more flashes, while a negative binomial model is used to predict the amount of lightning, conditional on one or more flashes occurring. The scheme is applied to output from three mesoscale models during an independent test period (the 2006 warm season). The evaluation is performed using output from the National Centers for Environmental Prediction (NCEP) 13-km RUC (RUC13), the NCEP 12-km North American Mesoscale Model, and local high-resolution runs of the Weather Research and Forecasting (WRF) Model for a domain over south Florida. Forecasts from all three mesoscale models generally show positive skill through the 2100–2359 UTC period with respect to a model containing only climatology and persistence (L-CLIPER) and persistence alone. A forecast example using the high-resolution WRF Model is shown for 16–17 August 2006. Although the exact timing and placement of forecast lightning are not perfect, there generally is good agreement between the forecasts and their verification, with most of the observed lightning occurring within the higher forecast probability contours.
The Integral Role of a Diabatic Rossby Vortex in a Heavy Snowfall Event
Authors: Moore Richard W. , Montgomery Michael T. , Davies Huw C.
Published: July 2008

On 24–25 February 2005, a significant East Coast cyclone deposited from 4 to nearly 12 in. (∼10–30 cm) of snow on parts of the northeastern United States. The heaviest snowfall and most rapid deepening of the cyclone coincided with the favorable positioning of an upper-level, short-wave trough immediately upstream of a preexisting surface cyclone. The surface cyclone in question formed approximately 15 h before the heaviest snowfall along a coastal front in a region of frontogenesis and heavy precipitation. The incipient surface cyclone subsequently intensified as it moved to the northeast, consistently generating the strongest convection to the east-northeast of the low-level circulation center. The use of potential vorticity (PV) inversion techniques and a suite of mesoscale model simulations illustrates that the early intensification of the incipient surface cyclone was primarily driven by diabatic effects and was not critically dependent on the upper-level wave. These facts, taken in conjunction with the observed structure, energetics, and Lagrangian evolution of the incipient surface disturbance, identify it as a diabatic Rossby vortex (DRV). The antecedent surface vorticity spinup associated with the DRV phase of development is found to be integral to the subsequent rapid growth. The qualitative similarity with a number of observed cases of explosive cyclogenesis leaves open the possibility that a DRV-like feature comprises the preexisting positive low-level PV anomaly in a number of cyclogenetic events that exhibit a two-stage evolution.
Mesoscale Features Associated with Tropical Cyclone Formations in the Western North Pacific
Authors: Lee Cheng-Shang , Cheung Kevin K. W. , Hui Jenny S. N. , Elsberry Russell L.
Published: July 2008

The mesoscale features of 124 tropical cyclone formations in the western North Pacific Ocean during 1999–2004 are investigated through large-scale analyses, satellite infrared brightness temperature (TB), and Quick Scatterometer (QuikSCAT) oceanic wind data. Based on low-level wind flow and surge direction, the formation cases are classified into six synoptic patterns: easterly wave (EW), northeasterly flow (NE), coexistence of northeasterly and southwesterly flow (NE–SW), southwesterly flow (SW), monsoon confluence (MC), and monsoon shear (MS). Then the general convection characteristics and mesoscale convective system (MCS) activities associated with these formation cases are studied under this classification scheme. Convection processes in the EW cases are distinguished from the monsoon-related formations in that the convection is less deep and closer to the formation center. Five characteristic temporal evolutions of the deep convection are identified: (i) single convection event, (ii) two convection events, (iii) three convection events, (iv) gradual decrease in TB, and (v) fluctuating TB, or a slight increase in TB before formation. Although no dominant temporal evolution differentiates cases in the six synoptic patterns, evolutions ii and iii seem to be the common routes taken by the monsoon-related formations. The overall percentage of cases with MCS activity at multiple times is 63%, and in 35% of cases more than one MCS coexisted. Most of the MC and MS cases develop multiple MCSs that lead to several episodes of deep convection. These two patterns have the highest percentage of coexisting MCSs such that potential interaction between these systems may play a role in the formation process. The MCSs in the monsoon-related formations are distributed around the center, except in the NE–SW cases in which clustering of MCSs is found about 100–200 km east of the center during the 12 h before formation. On average only one MCS occurs during an EW formation, whereas the mean value is around two for the other monsoon-related patterns. Both the mean lifetime and time of first appearance of MCS in EW are much shorter than those developed in other synoptic patterns, which indicates that the overall formation evolution in the EW case is faster. Moreover, this MCS is most likely to be found within 100 km east of the center 12 h before formation. The implications of these results to internal mechanisms of tropical cyclone formation are discussed in light of other recent mesoscale studies.
Convective Storm Initiation in a Moist Tropical Environment
Authors: Lima Maria Andrea , Wilson James W.
Published: July 2008

Radar and satellite data from the Tropical Rainfall Measuring Mission–Large-Scale Biosphere–Atmosphere (TRMM–LBA) project have been examined to determine causes for convective storm initiation in the southwest Amazon region. The locations and times of storm initiation were based on the National Center for Atmospheric Research (NCAR) S-band dual-polarization Doppler radar (S-Pol). Both the radar and the Geostationary Operational Environmental Satellite-8 (GOES-8) visible data were used to identify cold pools produced by convective precipitation. These data along with high-resolution topographic data were used to determine possible convective storm triggering mechanisms. The terrain elevation varied from 100 to 600 m. Tropical forests cover the area with numerous clear-cut areas used for cattle grazing and farming. This paper presents the results from 5 February 1999. A total of 315 storms were initiated within 130 km of the S-Pol radar. This day was classified as a weak monsoon regime where convection developed in response to the diurnal cycle of solar heating. Scattered shallow cumulus during the morning developed into deep convection by early afternoon. Storm initiation began about 1100 LST and peaked around 1500–1600 LST. The causes of storm initiation were classified into four categories. The most common initiation mechanism was caused by forced lifting by a gust front (GF; 36%). Forcing by terrain (>300 m) without any other triggering mechanism accounted for 21% of the initiations and colliding GFs accounted for 16%. For the remaining 27% a triggering mechanism was not identified. Examination of all days during TRMM–LBA showed that this one detailed study day was representative of many days. A conceptual model of storm initiation and evolution is presented. The results of this study should have implications for other locations when synoptic-scale forcing mechanisms are at a minimum. These results should also have implications for very short-period forecasting techniques in any location where terrain, GFs, and colliding boundaries influence storm evolution.
Assimilation of Simulated Polarimetric Radar Data for a Convective Storm Using the Ensemble Kalman Filter. Part II: Impact of Polarimetric Data on Storm Analysis
Authors: Jung Youngsun , Xue Ming , Zhang Guifu , Straka Jerry M.
Published: July 2008

A data assimilation system based on the ensemble square-root Kalman filter (EnSRF) is extended to include the additional capability of assimilating polarimetric radar variables. It is used to assess the impact of assimilating additional polarimetric observations on convective storm analysis in the Observing System Simulation Experiment (OSSE) framework. The polarimetric variables considered include differential reflectivity ZDR, reflectivity difference Zdp, and specific differential phase KDP. To simulate the observational data more realistically, a new error model is introduced for characterizing the errors of the nonpolarimetric and polarimetric radar variables. The error model includes both correlated and uncorrelated error components for reflectivities at horizontal and vertical polarizations (ZH and ZV, respectively). It is shown that the storm analysis is improved when polarimetric variables are assimilated in addition to ZH or in addition to both ZH and radial velocity Vr. Positive impact is largest when ZDR, Zdp, and KDP are assimilated all together. Improvement is generally larger in vertical velocity, water vapor, and rainwater mixing ratios. The rainwater field benefits the most while the impacts on horizontal wind components and snow mixing ratio are smaller. Improvement is found at all model levels even though the polarimetric data, after the application of thresholds, are mostly limited to the lower levels. Among ZDR, Zdp, and KDP, ZDR is found to produce the largest positive impact on the analysis. It is suggested that ZDR provides more independent information than the other variables. The impact of polarimetric data is also expected to be larger when they are used to retrieve drop size distribution parameters. The polarimetric radar data thresholding prior to assimilation is found to be necessary to minimize the impact of noise. This study is believed to be the first to directly assimilate (simulated) polarimetric data into a numerical model.
Assessing the Skill of an All-Season Statistical Forecast Model for the Madden–Julian Oscillation
Authors: Jiang Xianan , Waliser Duane E. , Wheeler Matthew C. , Jones Charles , Lee Myong-In , Schubert Siegfried D.
Published: July 2008

Motivated by an attempt to augment dynamical models in predicting the Madden–Julian oscillation (MJO), and to provide a realistic benchmark to those models, the predictive skill of a multivariate lag-regression statistical model has been comprehensively explored in the present study. The predictors of the benchmark model are the projection time series of the leading pair of EOFs of the combined fields of equatorially averaged outgoing longwave radiation (OLR) and zonal winds at 850 and 200 hPa, derived using the approach of Wheeler and Hendon. These multivariate EOFs serve as an effective filter for the MJO without the need for bandpass filtering, making the statistical forecast scheme feasible for the real-time use. Another advantage of this empirical approach lies in the consideration of the seasonal dependence of the regression parameters, making it applicable for forecasts all year-round. The forecast model exhibits useful extended-range skill for a real-time MJO forecast. Predictions with a correlation skill of greater than 0.3 (0.5) between predicted and observed unfiltered (EOF filtered) fields still can be detected over some regions at a lead time of 15 days, especially for boreal winter forecasts. This predictive skill is increased significantly when there are strong MJO signals at the initial forecast time. The analysis also shows that predictive skill for the upper-tropospheric winds is relatively higher than for the low-level winds and convection signals. Finally, the capability of this empirical model in predicting the MJO is further demonstrated by a case study of a real-time “hindcast” during the 2003/04 winter. Predictive skill demonstrated in this study provides an estimate of the predictability of the MJO and a benchmark for the dynamical extended-range models.
An Indirect Effect of Ice Nuclei on Atmospheric Radiation
Authors: Zeng Xiping , Tao Wei-Kuo , Zhang Minghua , Hou Arthur Y. , Xie Shaocheng , Lang Stephen , Li Xiaowen , Starr David O’C. , Li Xiaofan , Simpson Joanne
Published: July 2008

A three-dimensional cloud-resolving model (CRM) with observed large-scale forcing is used to study how ice nuclei (IN) affect the net radiative flux at the top of the atmosphere (TOA). In all the numerical experiments carried out, the cloud ice content in the upper troposphere increases with IN number concentration via the Bergeron process. As a result, the upward solar flux at the TOA increases whereas the infrared one decreases. Because of the opposite response of the two fluxes to IN concentration, the sensitivity of the net radiative flux at the TOA to IN concentration varies from one case to another.

Six tropical and three midlatitudinal field campaigns provide data to model the effect of IN on radiation in different latitudes. Classifying the CRM simulations into tropical and midlatitudinal and then comparing the two types reveals that the indirect effect of IN on radiation is greater in the middle latitudes than in the tropics. Furthermore, comparisons between model results and observations suggest that observational IN data are necessary to evaluate long-term CRM simulations.
An Energetics Study of Wintertime Northern Hemisphere Storm Tracks under 4 × CO2 Conditions in Two Ocean–Atmosphere Coupled Models
Authors: Laîné Alexandre , Kageyama Masa , Salas-Mélia David , Ramstein Gilles , Planton Serge , Denvil Sébastien , Tyteca Sophie
Published: July 2008

Different possible behaviors of winter Northern Hemisphere storm tracks under 4 × CO2 forcing are considered by analyzing the response of two of the ocean–atmosphere coupled models that were run for the fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR4), namely the Institut Pierre Simon Laplace’s global coupled model (IPSL-CM4) and the Centre National de Recherches Meteorologiques’s coupled ocean–atmosphere model (CNRM-CM3). It is interesting to compare these models due to their very different responses, especially concerning the North Atlantic storm track.

A local energetics study of the synoptic variability in both models is performed, derived from the eddy energy equations, including diabatic terms. The ability of both models to simulate the present-day eddy energetics is considered, indicating no major discrepancies.

Both models indicate that the primary cause for synoptic activity changes at the western end of the storm tracks is related to the baroclinic conversion process, due to mean temperature gradient changes in some localized regions of the western oceanic basins, but also resulting from changes in the eddy efficiency to convert energy from the mean flow. Farther downstream, latent heat release during the developing and mature stages of eddies becomes an important eddy energy source especially in terms of changes between 4 × CO2 and preindustrial conditions. This diabatic process amplifies the upstream synoptic (hence usually baroclinic) changes, with more and/or stronger storms implying more latent heat being released (and the converse being true for weaker synoptic activity). This amplification is asymmetrical for the models considered under the simulated 4 × CO2 conditions, due to a greater amount of water vapor contained in warmer air and hence the potential for more condensation for a given synoptic activity. The magnitude of the reduced latent heating is attenuated, whereas increased latent heating is strengthened. Ageostrophic geopotential fluxes are also important in relocating eddy kinetic energy, especially in the vertical.
A Five-Year Record of Summer Melt on Eurasian Arctic Ice Caps
Authors: Sharp Martin , Wang Libo
Published: July 2008

Climatologies and annual anomaly patterns (2000–04) of melt season duration and dates of melt onset/freeze-up on Eurasian Arctic ice masses were derived from Quick Scatterometer (QuikSCAT) backscatter data. Severnaya Zemlya, Russia, has later melt onset, earlier freeze-up, and shorter melt seasons than Svalbard, Norway/Novaya Zemlya, Russia. In all three archipelagos 2001 was the longest melt season and 2000 was the shortest. Anomalously long (short) melt seasons on Svalbard were associated with negative (positive) sea ice concentration anomalies along the north coast in June and August. Annual mean melt duration was strongly correlated with the mean (June + August) NCEP–NCAR reanalysis 850-hPa air temperature, allowing reconstruction of melt durations for the period of 1948–2005. The 2000–04 pentad had the second or third longest mean melt duration of all pentads in the 1950–2004 epoch, while the 1950–54 pentad probably had the longest. Integration of these results with previous results from Greenland and the Canadian Arctic identifies 2002 as the longest melt season in the 2000–04 period across the Arctic as a whole, and 2001 as the shortest. Correlation of melt duration anomalies for 19 discrete regions identifies seven spatially coherent areas of the Arctic with common patterns of variability in annual melt duration.
A Precipitation Climatology and Dataset Intercomparison for the Western United States
Authors: Guirguis Kristen J. , Avissar Roni
Published: July 2008

This paper presents the results of a regionalization study of the precipitation climate of the western United States using principal component analysis. Past eigen-based regionalization studies have relied on rain gauge networks, which is restrictive because rain gauge coverage is sparse, especially over complex terrain that exists in the western United States. Here, the use of alternate data products is examined by conducting a comparative regionalization using nine precipitation datasets used in hydrometeorological research. Five unique precipitation climates are identified within the western United States, which have centers and boundaries that are physically reasonable and that highlight the relationship between the precipitation climatology and local topography. Using the congruence coefficient as the measure of similarity between principal component solutions, the method is found to be generally stable across datasets. The exception is the National Centers for Environmental Prediction–Department of Energy (NCEP–DOE) Reanalysis 2, which frequently demonstrates only borderline agreement with the other datasets. The loading pattern differences among datasets are shown to be primarily a result of data differences in the representation of (i) precipitation over the Rocky Mountains, (ii) the eastward wet-to-dry precipitation gradient that occurs during the cold season, (iii) the magnitude and spatial extent of the North American monsoon signal, and (iv) precipitation in the desert southwest during spring and summer. Sensitivity tests were conducted to determine whether the spatial resolution and temporal domain of the input data would dramatically affect the solution, and these results show the methodology to be stable to differences in spatial/temporal data features. The results suggest that alternate data products can be used in regionalization studies, which has applications for rain gauge installation and planning, climate research, and numerical modeling experiments.
Investigation of the Sensitivity of Water Cycle Components Simulated by the Canadian Regional Climate Model to the Land Surface Parameterization, the Lateral Boundary Data, and the Internal Variability
Authors: Music Biljana , Caya Daniel
Published: July 2008

This study investigates the sensitivity of components of the hydrological cycle simulated by the Canadian Regional Climate Model (CRCM) to lateral boundary forcing, the complexity of the land surface scheme (LSS), and the internal variability arising from different models’ initial conditions. This evaluation is a contribution to the estimation of the uncertainty associated to regional climate model (RCM) simulations. The analysis was carried out over the period 1961–99 for three North American watersheds, and it looked at climatological seasonal means, mean (climatological) annual cycles, and interanual variability. The three watersheds—the Mississippi, the St. Lawrence, and the Mackenzie River basins—were selected to cover a large range of climate conditions. An evaluation of simulated water budget components with available observations was also included in the analysis.

Results indicated that the response of climatological means and annual cycles of water budget components to land surface parameterizations and lateral boundary conditions varied from basin to basin. Sensitivity to lateral boundary conditions is, in general, smaller than sensitivity to LSS and tends to be stronger for the northern basins (Mackenzie and St. Lawrence). Interannual variability was unaffected by changes in LSS and in driving data. Internal variability triggered by different initial conditions and the nonlinear nature of the climate model did not significantly affect either the 39-yr climatology, the climatological annual cycles, or the interannual variability. A comparison with observations suggests that although the simple Manabe-based LSS may be adequate for simulations of climatological means, skillful simulation of annual cycles require the use of a state-of-the-art LSS.
Scene Radiance–Dependent Intersatellite Biases of HIRS Longwave Channels
Authors: Shi Lei , Bates John J. , Cao Changyong
Published: July 2008

Measurements from the simultaneous nadir overpass (SNO) observations of the High Resolution Infrared Radiation Sounder (HIRS) are examined. The SNOs are the measurements taken at the orbital intersections of each pair of satellites viewing the same Earth target within a few seconds at high latitudes. The dataset includes satellites from NOAA-6 through NOAA-17 from 1981 to 2004. The authors found that for many channels, intersatellite biases vary significantly with respect to scene radiances. For a number of these channels, the change of the intersatellite bias within a channel can be larger than 1 mW (m2 sr cm−1)−1, which is approximately 1 K in brightness temperature, across the channel scene radiance ranges. Many of the channels with large variations of intersatellite biases are the tropospheric sounding channels centered along the sharp slope of the transmission line. These channels are particularly sensitive to the difference in spectral response functions from satellite to satellite. This radiance-dependency feature of the biases is an important factor to consider when performing intersatellite calibrations.
Clutter Suppression for Staggered PRT Waveforms
Authors: Moisseev Dmitri N. , Nguyen Cuong M. , Chandrasekar V.
Published: July 2008

This paper presents a clutter suppression methodology for staggered pulse repetition time (PRT) observations. It is shown that spectral moments of precipitation echoes can be accurately estimated even in cases where clutter-to-signal ratios are high by using a parametric time domain method (PTDM).

Based on radar signal simulations, the accuracy of the proposed method is evaluated for various observation conditions. The performance of PTDM is demonstrated by the implementation of the staggered PRT at the Colorado State University–University of Chicago–Illinois State Water Survey (CSU–CHILL). Based on this study, it is found that the accuracy of the retrieval is comparable to the current state of the art methods applied to the uniformly sampled observations and that the estimated velocity is unbiased for the complete Nyquist range.
Contributions from a Local Ensemble Prediction System (LEPS) for Improving Fog and Low Cloud Forecasts at Airports
Authors: Roquelaure Stevie , Bergot Thierry
Published: July 2008

At Paris’ international airport, named Roissy Charles de Gaulle (CdG), air traffic safety and management as well as economic issues related to poor visibility conditions are crucial. Meteorologists face the challenge of supplying airport authorities with accurate forecasts of fog and cloud ceiling. A specific event, which is called a low visibility procedure (LVP), has been defined for a visibility under 600 m and/or a ceiling under 60 m. Forecasters have to provide two LVP human predictions at 0600 and 0900 local time, providing estimates of the LVP occurrence on the airport area for the next 3 h. This estimation has a probabilistic nature since the forecasters have to classify their forecasts into the following four forecast categories: “certain,” “likely,” “unlikely,” and “excluded.” A Local Ensemble Prediction System (LEPS) has been recently designed around the Code de Brouillard á l’Echelle Locale–Interactions between Soil, Biosphere, and Atmosphere (COBEL-ISBA) numerical model and has been tested to assess the predictability of LVP events and estimate their likelihood. This work compares the operational human LVP forecasts with LEPS LVP forecasts during the winter season 2004–05. This study shows that the use of LEPS for LVP prediction can significantly improve the current design of the operational LVP forecast by providing reliable forecasts up to 12 h ahead of time. Moreover, the system can be easily run on a personal computer without high computational resources.
The Second Person
Authors: Litowitz Bonnie E.
Published: July 2008

Unlike third-person sciences, psychoanalysis is the science of the second person. Briefly tracing the history of our focus on a second person, this paper contrasts two different approaches-the dyadic and the dialogic, proposing the latter as the better model for our field and the one that marks our unique contribution to other disciplines.
The Reality Principle, Tragic Knots, and the Analytic Process
Authors: Schafer Roy
Published: July 2008

Civilization and Its Discontents is shown to occupy a special place in Freud's development of psychoanalytic theory and technique. Especially emphasized is its implications for an inclusive understanding of the reality principle. The concept tragic knots is then defined and used to emphasize Freud's readiness to include tragic elements in that principle. An extended section then illustrates the spread of tragic knots into several diverse aspects of human existence: victimization, intimacy, and maintaining privacy. Finally, implications are drawn for the clinical assessment of working through unconscious conflicts.
Sibling Differentiation, Identity Development, and the Lateral Dimension of Psychic Life
Authors: Vivona Jeanine M.
Published: July 2008

The lateral dimension of psychic life, lived through relationships with siblings and their substitutes, is structured around a distinct psychic challenge: to find one's unique place in a world of similar others. Like the challenge that structures the vertical parent-child dimension, the lateral challenge is fraught with conflict and ambivalence; its resolution imbues psychic structure. That resolution may be accomplished through a process of differentiation, an active and unconscious process of identity development by which a child amplifies differences with siblings and minimizes similarities. Differentiation from siblings serves to mitigate interpersonal rivalry with them and to ease internal conflict associated with the lateral dimension. Three clinical examples are offered to illustrate the operation of sibling differentiation and its costs, particularly in terms of constricted identity and attenuated relationships with siblings and peers. Differentiation as a process of becoming what the other is not has been eclipsed by identification in psychoanalytic theories of identity development. Yet differentiation is a common strategy for resolving the primary rivalries and conflicts of the lateral dimension, and has unique developmental and clinical implications.
The Reassembly of the Body from Parts: Psychoanalytic Reflections on Death, Resurrection, and Cannibalism
Authors: Gottlieb Richard M.
Published: July 2008

Terror of the dismemberment, disintegration, and decay of the body after death has been represented in ritual, myth, legend, art, and religious belief throughout the ages. So too has the wished-for triumph over these inevitable processes. Commonly, bodily experience after death is represented mentally in cannibalistic ideas of eating and being eaten, which are then countered by the wishful undoing of cannibalistic destruction through its reversal: swallowing as regurgitation, dismemberment as re-memberment, disintegration as reassembly. Luca Signorelli's fresco The Resurrection of the Flesh is part of his celebrated group of decorations (1499-1504) of the Cappella Nuova in the cathedral at Orvieto. The doctrinal, iconographic, social, and political contexts of this admired and influential work are explored in order to illustrate how and why this painting represents our greatest fears, along with our triumph over them, as well as our most destructive urges and their reparative counterparts. The photographer Sally Mann has explored these same themes. In What Remains (2003), a series of pictures with accompanying text, Mann documents her exhumation and reassembly of the body of her beloved pet greyhound. Two clinical examples illustrate some ways these concerns (cannibalism and reassembly) may make their appearance in psychoanalytic work.
Individual Differences in Melancholy Gender Among Women: Does Ambivalence Matter?
Authors: Jay Meg
Published: July 2008

This research offers an empirical investigation inspired by Butler's theory of melancholy gender (1995) and a revision of this theory (Jay 2007a). Psychoanalytic feminist theory is drawn on to suggest that melancholy and gender are more likely to be associated in female development than in male development, and Freud's theory of melancholy (1917) is taken to suggest that ambivalence predicts individual differences in melancholy gender among women. In a longitudinal study of women's adult development, an examination of femininity, depressive symptoms, and ambivalence in attachment was conducted in order to evaluate these claims. Findings show that depressive symptoms and femininity are significantly correlated within the sample, but that individual differences in melancholy gender exist. To understand these differences, an analysis was conducted to determine whether ambivalence in attachment accounts for the relation between depressive symptoms and femininity; complementary analyses examined whether low ambivalence in attachment attenuates, or lessens, the relation between femininity and depressive symptoms. Results from these analyses support the notion that it is not the loss and internalization of the same-sex object choice per se that results in melancholy gender in women, as Butler argues; rather, it is the internalization of a lost, ambivalent same-sex attachment that forges the link between melancholy and gender. Narrative material is presented to personify melancholy and unmelancholy gender.
The Dynamics of Empirically Derived Factors in the Therapeutic Relationship
Authors: Nuetzel Eric J. , Larsen Randy J. , Prizmic Zvjezdana
Published: July 2008

The therapeutic relationship is the source of major concepts in psychoanalytic clinical theory. Such concepts as resistance, transference, countertransference, and the alliance are fundamental, even though there may be shifts in meaning between theoretical schools and clinical contexts. In the clinical psychoanalytic literature, disagreement exists over the nature of the alliance and its essential components. Empirical studies using reliable patient, therapist, and observer scales to assess the alliance demonstrate a correlation with psychotherapeutic gains. In the study reported here, thirteen patients were followed for 6 to 33 months of psychodynamic psychotherapy, during which time their views of the therapeutic relationship were assessed, and several experiential measures taken, all on a weekly basis. Statistical analyses reveal that the therapeutic relationship, as reflected in the patients' weekly responses to the St. Louis Therapeutic Relationship Rating Scale, has four distinct components: therapeutic alliance, resistance, transference love, and negative transference. On a week-by-week basis, the therapeutic alliance was the strongest predictor of improvement in patient-reported general adjustment, as reflected in such areas as self-esteem, positive affect, social relations, work productivity, satisfaction, and optimism. Time plots of the variables show the typical time course for the components of the therapeutic relationship, as well as for improvement on the experiential variables. Results indicate that the therapeutic alliance, transference, and resistance are central components of the psychotherapeutic relationship, which in turn predict the ongoing life experience of the patient.
Marguerite V. Hood and Music Education Radio Broadcasts in Rural Montana (1937-39)
Authors: Cooper Shelly
Published: July 2008

The impact of the radio in the 1930s can be compared to the force of change in people's lives today caused by current technology. Marguerite V Hood (1903-92), a recognized leader in the music education profession during the 1930s, understood the importance of music education radio broadcasts for rural one-room schools and music education classes. In 1936, she began a series of broadcasts in an effort to reach all children in Montana and was appointed radio director for the KGVO Montana School of the Air program. Hood recognized the necessity of using contemporary resources in music education, a need that exists today. Music educators who offer learning experiences encompassing various music listening activities and musical styles through all types of media provide students with a rich, fertile environment for cultivating the understanding and appreciation of all music genres.
The Relationship between Developmental Tonal Aptitude and Singing Achievement among Kindergarten, First-, Second-, and Third-Grade Students
Authors: Hornbach Christina M. , Taggart Cynthia C.
Published: July 2008

The purpose of this study was to determine the relationship between singing achievement and developmental tonal aptitude for students in kindergarten through third grade. In addition we investigated whether singing achievement differs according to grade level or school setting. Subjects (N = 162) were randomly selected kindergarten, first-; second-, and third-grade children from schools in two different school districts. Correlations between composite singing achievement scores and scores on the Primary Measures of Music Audiation-Tortal reflected no meaningful relationships between singing achievement and developmental tonal aptitude. Two-way analysis of variance revealed no significant interaction between school and grade. However, there were significant main effects for school and grade (p <. 001). With the exception of third-grade students, older students demonstrated greater singing achievement than younger students.
The Role of the String Project in Teacher Training and Community Music Education
Authors: Byo James L. , Cassidy Jane W.
Published: July 2008

The National String Project Consortium was designed to encourage string education majors to become string teachers and to stimulate growth of new school orchestra programs. The purpose of this study was to evaluate the extent to which these goals were accomplished across 13 university sites in 2003-2004. Survey data were obtained from project directors, master teachers, student teachers, children, and parents (N = 1,458). Results indicated the majority of student teachers were music education majors who received professional and financial benefit from participation, and were engaged in authentic string teaching in productive and rewarding settings. Children studied string instruments under satisfying and affordable conditions. The String Project seems to have filled a void where school strings programs do not exist, or functioned to supplement strings instruction available in the schools.
Effect of Sex and Race Identification on Instrument Assignment by Music Educators
Authors: Johnson Christopher M. , Stewart Erin E.
Published: July 2008

The purpose of this study was to investigate the effect of sex and race identification on the assignment of instruments to beginning band students. Participants (N = 201) were music educators solicited by university professors across the United States. Participants completed an online survey about instrument assignments. Half the participants were sent to a site that had full-head pictures of 14 students and assigned them to one of six beginning band instruments. The other half of the participants were sent to a site that had pictures of the same students, but only the lips and dental aspects of the students' faces were visible. Results indicated that the ability to identify the sex and race of students had an effect only on the assignment of an instrument for 2 of the 14 students. No clear reason for the few differences could be linked to any sex or race factors; therefore, the assessment decisions are thought to be artifacts of individual pictures/students. The authors conclude that, generally, differences in instrument assignment could not be linked to the participants' ability to identify the sex or race of the student.