On the accuracy of TOVS temperature fields in an Arctic case study

Abstract The diurnally varying atmospheric boundary layer observed during the Wangara (Australia) case study is simulated using the recently proposed locally averaged scale-dependent dynamic subgrid-scale (SGS) model. This tuning-free SGS model enables one to dynamically compute the Smagorinsky coefficient and the subgrid-scale Prandtl number based on the local dynamics of the resolved velocity and temperature fields. It is shown that this SGS-model-based large-eddy simulation (LES) has the ability to faithfully reproduce the characteristics of observed atmospheric boundary layers even with relatively coarse resolutions. In particular, the development, magnitude, and location of an observed nocturnal low-level jet are depicted quite well. Some well-established empirical formulations (e.g., mixed layer scaling, spectral scaling) are recovered with good accuracy by this SGS parameterization. The application of this new-generation dynamic SGS modeling approach is also briefly delineated to address several practical wind-energy-related issues.

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Determining stages of cirrus evolution: a cloud classification scheme

Atmospheric Measurement Techniques ◽

10.5194/amt-10-1653-2017 ◽

2017 ◽

Vol 10 (5) ◽

pp. 1653-1664 ◽

Cited By ~ 5

Author(s):

Benedikt Urbanek ◽

Silke Groß ◽

Andreas Schäfler ◽

Martin Wirth

Keyword(s):

Classification Scheme ◽

Cirrus Clouds ◽

Radiative Properties ◽

Temperature Fields ◽

High Spectral Resolution ◽

Cloud Properties ◽

Lidar Measurements ◽

Lee Wave

Abstract. Cirrus clouds impose high uncertainties on climate prediction, as knowledge on important processes is still incomplete. For instance it remains unclear how cloud microphysical and radiative properties change as the cirrus evolves. Recent studies classify cirrus clouds into categories including in situ, orographic, convective and liquid origin clouds and investigate their specific impact. Following this line, we present a novel scheme for the classification of cirrus clouds that addresses the need to determine specific stages of cirrus evolution. Our classification scheme is based on airborne Differential Absorption and High Spectral Resolution Lidar measurements of atmospheric water vapor, aerosol depolarization, and backscatter, together with model temperature fields and simplified parameterizations of freezing onset conditions. It identifies regions of supersaturation with respect to ice (ice-supersaturated regions, ISSRs), heterogeneous and homogeneous nucleation, depositional growth, and ice sublimation and sedimentation with high spatial resolution. Thus, all relevant stages of cirrus evolution can be classified and characterized. In a case study of a gravity lee-wave-influenced cirrus cloud, encountered during the ML-CIRRUS flight campaign, the applicability of our classification is demonstrated. Revealing the structure of cirrus clouds, this valuable tool might help to examine the influence of evolution stages on the cloud's net radiative effect and to investigate the specific variability of optical and microphysical cloud properties in upcoming research.

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A Case Study of Hyperthermia Induced Temperature Computations in Human Sarcomas Using Discrete Vasculature and Relative Perfusion Maps

10.1115/imece2001/htd-24417 ◽

2001 ◽

Author(s):

Oana I. Craciunescu ◽

Bas W. Raaymakers ◽

Alexis N. T. J. Kotte ◽

Shiva K. Das ◽

Thaddeus V. Samulski ◽

...

Keyword(s):

Heat Transfer ◽

Mr Angiography ◽

Temperature Fields ◽

Continuum Models ◽

Resonance Imaging ◽

Mr Thermometry ◽

Complex Heat Transfer ◽

Perfusion Maps ◽

Large Vessels

Abstract One of the most important technical aspects in clinical hyperthermia is the ability to measure and/or simulate the 3D temperature fields. Related to that, an essential part is the way in which the complex heat transfer related to vasculature is described. We report here the results of a collaboration between the hyperthermia modeling groups from the UMC Utrecht, The Netherlands, and Duke UMC, USA. Utrecht’s hyperthermia group has developed a flexible, discrete vasculature thermal model (DIVA) (Kotte et al. 1996) that describes the heat transfer related to discrete vasculature. The vasculature was imaged using MR angiography. To account for the smaller vessels that are responsible for the significant bioheat transport, relative perfusion maps measured at Duke using dynamic enhanced-magnetic resonance imaging were used. Alternatively, the VAMP program (Van Leeuwen et al. 1998) was used to artificially generate smaller vasculature. The cases with discretized vasculature were compared to continuum models where either heterogeneous isotropic perfusion, or relative perfusion maps were used. All simulations were compared to MR thermometry data. The conclusion is that for tumors crossed by or near large vessels, a combination of large vessels discretization and perfusion maps yields temperatures that match very well the MR thermometry data.

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Cloud Initialization in the Rapid Update Cycle of HIRLAM

Weather and Forecasting ◽

10.1175/waf-d-13-00071.1 ◽

2014 ◽

Vol 29 (5) ◽

pp. 1120-1133 ◽

Cited By ~ 4

Author(s):

Siebren de Haan ◽

Siebe H. van der Veen

Keyword(s):

Cloud Cover ◽

Negative Impact ◽

Heavy Precipitation ◽

Temperature Fields ◽

Cloud Base ◽

Limited Area ◽

Forecast Performance ◽

First Case ◽

Synoptic Observations

Abstract The Nowcasting Satellite Application Facility (NWC SAF) cloud mask from the Meteosat Second Generation (MSG) satellite is introduced in the initialization step of an hourly Rapid Update Cycle (RUC) of the High Resolution Limited Area Model (HIRLAM). MSG cloud-top temperatures and synoptic cloud-base height information are combined at analysis time. This cloud initialization scheme is applied to an experimental run, which is a copy of the operational Royal Netherlands Meteorological Institute [Koninklijk Nederlands Meteorologisch Instituut (KNMI)] RUC model. The experimental run was employed during the period June–December 2011. The RUC model has a forecast length of 6 h. Cloud cover forecasts are verified against MSG cloud cover information and synoptic observations. Forecasts of precipitation, surface pressure, 2-m temperature, and upper-air temperature are verified against synoptic observations and aircraft temperature observations. It is shown that including MSG cloud information in the RUC considerably improves the forecasts of most of these model fields, when compared to the operational control RUC. Both the bias and standard deviation of the errors of the cloud cover forecast are reduced substantially. Forecasts of light precipitation show a slight negative impact, but forecasts of heavy precipitation become better. The bias in 3D temperature fields disappears nearly completely. The error bias of 2-m temperatures has become larger. Two case studies are presented. The first case study had very good forecast performance with respect to low clouds when compared to the reference run. The second case study shows an ambiguous impact; there are still some deficiencies in the cloud initialization and cloud forecast when focusing on a single location.

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Deep learning for short-term temperature forecasts with video prediction methods

10.5194/egusphere-egu2020-17748 ◽

2020 ◽

Author(s):

Bing Gong ◽

Severin Hußmann ◽

Amirpasha Mozaffari ◽

Jan Vogelsang ◽

Martin Schultz

Keyword(s):

Deep Learning ◽

Data Extraction ◽

Temperature Fields ◽

Weather Data ◽

Video Frame ◽

Full Life Cycle ◽

Training Post ◽

Parallel Workflow ◽

Learning Architectures

<p>This study explores the adaptation of state-of-the-art deep learning architectures for video frame prediction in the context of weather and climate applications. A proof-of-concept case study was performed to predict surface temperature fields over Europe for up to 20 hours based on ERA5 reanalyses weather data. Initial results have been achieved with a PredNet and a GAN-based architecture by using various combinations of temperature, surface pressure, and 500 hPa geopotential as inputs. The results show that the GAN-based architecture outperforms the PredNet. To facilitate the massive data processing and testing of various deep learning architectures, we have developed a containerized parallel workflow for the full life-cycle of the application, which consists of data extraction, data pre-processing, training, post-processing and visualisation of results. The training for PredNet was parallelized on JUWELS supercomputer at JSC, and the training scalability performance was also evaluated.</p>

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The Genesis and Internal Dynamics of El Salvador's People's Revolutionary Army, 1970–1976

Behavioral and Brain Sciences ◽

10.1017/s0140525x13009850 ◽

2014 ◽

Vol 38 (01) ◽

pp. 102-129

Author(s):

ALBERTO MARTÍN ÁLVAREZ ◽

EUDALD CORTINA ORERO

Keyword(s):

Latin America ◽

El Salvador ◽

Early Years ◽

Left Wing ◽

Internal Dynamics ◽

Internal Coherence ◽

The 1960S

AbstractUsing interviews with former militants and previously unpublished documents, this article traces the genesis and internal dynamics of the Ejército Revolucionario del Pueblo (People's Revolutionary Army, ERP) in El Salvador during the early years of its existence (1970–6). This period was marked by the inability of the ERP to maintain internal coherence or any consensus on revolutionary strategy, which led to a series of splits and internal fights over control of the organisation. The evidence marshalled in this case study sheds new light on the origins of the armed Salvadorean Left and thus contributes to a wider understanding of the processes of formation and internal dynamics of armed left-wing groups that emerged from the 1960s onwards in Latin America.

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Culture and the plasticity of perception

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002887 ◽

2020 ◽

Vol 43 ◽

Author(s):

Michael Lifshitz ◽

T. M. Luhrmann

Keyword(s):

Cultural Context ◽

Sensory Experience ◽

Cultural Learning ◽

The World

Abstract Culture shapes our basic sensory experience of the world. This is particularly striking in the study of religion and psychosis, where we and others have shown that cultural context determines both the structure and content of hallucination-like events. The cultural shaping of hallucinations may provide a rich case-study for linking cultural learning with emerging prediction-based models of perception.

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Dual systems for all: Higher-order, role-based relational reasoning as a uniquely derived feature of human cognition

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000451 ◽

2019 ◽

Vol 42 ◽

Author(s):

Daniel J. Povinelli ◽

Gabrielle C. Glorioso ◽

Shannon L. Kuznar ◽

Mateja Pavlic

Keyword(s):

Temporal Reasoning ◽

Higher Order ◽

Important Case ◽

Human Cognition ◽

Relational Reasoning ◽

Dual Systems ◽

First Order ◽

Reasoning System ◽

Role Based

Abstract Hoerl and McCormack demonstrate that although animals possess a sophisticated temporal updating system, there is no evidence that they also possess a temporal reasoning system. This important case study is directly related to the broader claim that although animals are manifestly capable of first-order (perceptually-based) relational reasoning, they lack the capacity for higher-order, role-based relational reasoning. We argue this distinction applies to all domains of cognition.

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Sociocultural memory development research drives new directions in gadgetry science

Behavioral and Brain Sciences ◽

10.1017/s0140525x19000979 ◽

2019 ◽

Vol 42 ◽

Author(s):

Penny Van Bergen ◽

John Sutton

Keyword(s):

Episodic Memory ◽

Autobiographical Memory ◽

Developmental Psychology ◽

Cross Cultural ◽

Memory Development ◽

Development Research ◽

Cultural Research ◽

New Directions ◽

Cross Cultural Research

Abstract Sociocultural developmental psychology can drive new directions in gadgetry science. We use autobiographical memory, a compound capacity incorporating episodic memory, as a case study. Autobiographical memory emerges late in development, supported by interactions with parents. Intervention research highlights the causal influence of these interactions, whereas cross-cultural research demonstrates culturally determined diversity. Different patterns of inheritance are discussed.

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