scholarly journals Sensitivity of U.S. summer precipitation to model resolution and convective parameterizations across gray zone resolutions

2017 ◽  
Vol 122 (5) ◽  
pp. 2714-2733 ◽  
Author(s):  
Yang Gao ◽  
L. Ruby Leung ◽  
Chun Zhao ◽  
Samson Hagos
Keyword(s):  
Summer Precipitation ◽  
Gray Zone ◽  
Model Resolution

scholarly journals Spatial and temporal variability of clouds and precipitation over Germany: multiscale simulations across the "gray zone"

2015 ◽  
Vol 15 (21) ◽  
pp. 12361-12384 ◽  
Author(s):  
C. Barthlott ◽  
C. Hoose
Keyword(s):  
Cloud Formation ◽  
Small Scale ◽  
Spatial And Temporal Variability ◽  
Gray Zone ◽  
Model Resolution ◽  
Eddy Simulation ◽  
Cosmo Model ◽  
Weather Events ◽  
Temporal And Spatial Variability ◽  
Convergence Zones

Abstract. This paper assesses the resolution dependance of clouds and precipitation over Germany by numerical simulations with the COnsortium for Small-scale MOdeling (COSMO) model. Six intensive observation periods of the HOPE (HD(CP)2 Observational Prototype Experiment) measurement campaign conducted in spring 2013 and 1 summer day of the same year are simulated. By means of a series of grid-refinement resolution tests (horizontal grid spacing 2.8, 1 km, 500, and 250 m), the applicability of the COSMO model to represent real weather events in the gray zone, i.e., the scale ranging between the mesoscale limit (no turbulence resolved) and the large-eddy simulation limit (energy-containing turbulence resolved), is tested. To the authors' knowledge, this paper presents the first non-idealized COSMO simulations in the peer-reviewed literature at the 250–500 m scale. It is found that the kinetic energy spectra derived from model output show the expected −5/3 slope, as well as a dependency on model resolution, and that the effective resolution lies between 6 and 7 times the nominal resolution. Although the representation of a number of processes is enhanced with resolution (e.g., boundary-layer thermals, low-level convergence zones, gravity waves), their influence on the temporal evolution of precipitation is rather weak. However, rain intensities vary with resolution, leading to differences in the total rain amount of up to +48 %. Furthermore, the location of rain is similar for the springtime cases with moderate and strong synoptic forcing, whereas significant differences are obtained for the summertime case with air mass convection. Domain-averaged liquid water paths and cloud condensate profiles are used to analyze the temporal and spatial variability of the simulated clouds. Finally, probability density functions of convection-related parameters are analyzed to investigate their dependance on model resolution and their impact on cloud formation and subsequent precipitation.

scholarly journals Simulation of summer precipitation diurnal cycles over the Tibetan Plateau at the gray-zone grid spacing for cumulus parameterization

2020 ◽  
Vol 54 (7-8) ◽  
pp. 3525-3539 ◽  
Author(s):  
Tinghai Ou ◽  
Deliang Chen ◽  
Xingchao Chen ◽  
Changgui Lin ◽  
Kun Yang ◽  
...  
Keyword(s):  
Tibetan Plateau ◽  
Summer Precipitation ◽  
Cumulus Parameterization ◽  
The Tibetan Plateau ◽  
Gray Zone ◽  
Grid Spacing ◽  
Diurnal Cycles

scholarly journals Spatial and Temporal Characteristics of Summer Precipitation over Central Europe in a Suite of High-Resolution Climate Models

2016 ◽  
Vol 29 (10) ◽  
pp. 3501-3518 ◽  
Author(s):  
Petter Lind ◽  
David Lindstedt ◽  
Erik Kjellström ◽  
Colin Jones
Keyword(s):  
High Resolution ◽  
Climate Models ◽  
Summer Precipitation ◽  
Horizontal Resolution ◽  
Added Value ◽  
Gray Zone ◽  
Mesoscale Dynamics ◽  
Lateral Boundary Conditions ◽  
Realistic Representation ◽  
Convection Parameterization

Abstract High-impact, locally intense rainfall episodes represent a major socioeconomic problem for societies worldwide, and at the same time these events are notoriously difficult to simulate properly in climate models. Here, the authors investigate how horizontal resolution and model formulation influence this issue by applying the HIRLAM–ALADIN Regional Mesoscale Operational NWP in Europe (HARMONIE) Climate (HCLIM) regional model with three different setups: two using convection parameterization at 15- and 6.25-km horizontal resolution (the latter within the “gray zone” scale), with lateral boundary conditions provided by ERA-Interim and integrated over a pan-European domain, and one with explicit convection at 2-km resolution (HCLIM2) over the Alpine region driven by the 15-km model. Seven summer seasons were sampled and validated against two high-resolution observational datasets. All HCLIM versions underestimate the number of dry days and hours by 20%–40% and overestimate precipitation over the Alpine ridge. Also, only modest added value was found for gray-zone resolution. However, the single most important outcome is the substantial added value in HCLIM2 compared to the coarser model versions at subdaily time scales. It better captures the local-to-regional spatial patterns of precipitation reflecting a more realistic representation of the local and mesoscale dynamics. Further, the duration and spatial frequency of precipitation events, as well as extremes, are closer to observations. These characteristics are key ingredients in heavy rainfall events and associated flash floods, and the outstanding results using HCLIM in a convection-permitting setting are convincing and encourage further use of the model to study changes in such events in changing climates.

Unusual Microstructure in Shock-Compacted Graphite

1970 ◽  
Vol 28 ◽  
pp. 474-475
Author(s):  
Lucien F. Trueb
Keyword(s):  
Mechanical Characteristic ◽  
Compression Wave ◽  
Gray Zone ◽  
Flyer Plate ◽  
Compacted Graphite ◽  
The Impact

Crushed and statically compressed Madagascar graphite that was explosively shocked at 425 kb by means of a planar flyer-plate is characterized by a black zone extending for 2 to 3 nun below the impact plane of the driver. Beyond this point, the material assumes the normal gray color of graphite. The thickness of the black zone is identical with the distance taken by the relaxation wave to overtake the compression wave.The main mechanical characteristic of the black material is its great hardness; steel scalpels and razor blades are readily blunted during attempts to cut it. An average microhardness value of 95-3 DPHN was obtained with a 10 kg load. This figure is a minimum because the indentations were usually cracked; 14.8 DPHN was measured in the gray zone.

The “gray zone” in fine-needle aspiration cytology of the organized mammography screening. Cytohistological correlation

2011 ◽  
Vol 152 (8) ◽  
pp. 292-295
Author(s):  
Mihály Bak ◽  
Éva Konyár ◽  
Ferenc Schneider ◽  
Mária Bidlek ◽  
Éva Szabó ◽  
...  
Keyword(s):  
Fine Needle Aspiration ◽  
Mammography Screening ◽  
Fine Needle Aspiration Cytology ◽  
Benign Lesion ◽  
Needle Aspiration ◽  
Gray Zone ◽  
Aspiration Cytology ◽  
Surgical Biopsy ◽  
Fine Needle ◽  
Needle Aspiration Cytology

The National Public Health Program has established the organized mammography screening in Hungary. The aim of this study was to conduct an audit of “gray zone” smears of the organized mammography screening in comparison with histopathological diagnoses. Methods: Cytology results were rated to C3 atypia probably benign and C4 suspicious of malignancy. Results: 1361 women had aspiration cytology performed from a total of 47,718 mammography non-negative lesions. 105 (7.8%) were diagnosed as C3, whereas 78 (5.7) as C4. Of the 105 patients with C3 diagnosis 61 (58%) patients underwent surgical biopsy. Histology proved malignancy in 20 (32.8%) cases, and benign lesion in 41 (67.2%) cases. All (100%) of the 78 patients with C4 diagnosis had open biopsies; 69 (88.4%) cases were histologically malignant and 9 (11.6%) cases were benign lesions. Conclusion: The auditing results of fine needle aspiration cytology of “gray zone” in organized mammography screening meet the proposed threshold values. Authors conclude that the “gray zone” category in breast cytology is useful and of value if used judiciously. Orv. Hetil., 2011, 152, 292–295.

An Interesting Case Report of A Concurrent Classic Hodgkin Lymphoma and Gray Zone Lymphoma in the Mediastinum

2020 ◽  
Vol 154 (Supplement_1) ◽  
pp. S110-S110
Author(s):  
B Mai ◽  
J Huddin ◽  
Z Hu
Keyword(s):  
B Cell ◽  
Hodgkin Lymphoma ◽  
Mediastinal Mass ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Gray Zone ◽  
Large B Cell Lymphoma ◽  
Classic Hodgkin Lymphoma ◽  
Atypical Cells ◽  
Large B Cell

Abstract Casestudy A 52-year-old female presented with night sweats, chills, anorexia, and weight loss. Computed tomography and positron emission tomography showed a soft tissue infiltration in the anterior mediastinum and hypermetabolic bilateral supraclavicular, mediastinal, right hilar, and left internal mammary lymph nodes. An anterior mediastinal mass resection and thymectomy was subsequently performed. Results Sections of the mediastinal mass showed Hodgkin/Reed-Sternberg cells (HRS) admixed with small lymphocytes, histiocytes, plasma cells, and eosinophils. The HRS cells are positive for CD30, CD15, and MUM1, faintly positive for PAX5, and negative for CD20, CD45, CD79a, and BCL6. The morphology and immunophenotype is diagnostic of nodular sclerosis classic Hodgkin lymphoma (CHL). Sections of the thymectomy specimen showed similar morphology, however, in an area that represents 10-20% of the specimen, there are nodular and diffuse lymphoid infiltrates consisting of small lymphocytes, histiocytes, and large atypical cells. The large atypical cells are positive for CD20, CD23, CD30, CD45, CD79a, BCL2, BCL6, MUM-1, and PAX5, and negative for CD1a, CD3, CD57, and Cyclin D1. The background small CD3-positive lymphocytes form a rosette around most of the large atypical cells. CD21 and CD23 stains highlight residual follicular structures. In situ hybridization for EBV-encoded RNA (EBER) is negative. The presence of residual follicular meshwork with an immunophenotype of large B cell lymphoma supports a diagnosis of a gray zone lymphoma (GZL). Overall, CHL is involving 80-90% and GZL is involving 10-20% of the thymic tissue. The patient was subsequently placed on ABVD chemotherapy and achieved remission. Conclusion An accurate diagnosis of GZL is challenging. GZL is a rare type of lymphoma with morphological features between CHL and diffuse large B-cell lymphoma (DLBCL). It is even rarer to encounter a CHL concurrently present with a GZL. The optimal therapeutic approach for cases with concurrent lymphoma diagnosed with CHL and GZL needs further investigation.

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