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A New Ensemble of Perturbed-Input-Parameter Simulations by the Community Atmosphere Model

Description: Uncertainty quantification (UQ) is a fundamental challenge in the numerical simulation of Earth's weather and climate, and other complex systems. It entails much more than attaching defensible error bars to predictions: in particular it includes assessing low-probability but high-consequence events. To achieve these goals with models containing a large number of uncertain input parameters, structural uncertainties, etc., raw computational power is needed. An automated, self-adapting search of t… more
Date: October 27, 2011
Creator: Covey, C; Brandon, S; Bremer, P T; Domyancis, D; Garaizar, X; Johannesson, G et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

NARAC Modeling During the Response to the Fukushima Dai-ichi Nuclear Power Plant Emergency

Description: This paper summarizes the activities of the National Atmospheric Release Advisory Center (NARAC) during the Fukushima Dai-ichi nuclear power plant crisis. NARAC provided a wide range of products and analyses as part of its support including: (1) Daily Japanese weather forecasts and hypothetical release (generic source term) dispersion predictions to provide situational awareness and inform planning for U.S. measurement data collection and field operations; (2) Estimates of potential dose in Jap… more
Date: February 14, 2012
Creator: Sugiyama, G.; Nasstrom, J. S.; Probanz, B.; Foster, K. T.; Simpson, M.; Vogt, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign

Description: This report documents the history of attempts to directly measure cloud extinction, the current measurement device known as the Cloud Extinction Probe (CEP), specific problems with direct measurement of extinction coefficient, and the attempts made here to address these problems. Extinction coefficient is one of the fundamental microphysical parameters characterizing bulk properties of clouds. Knowledge of extinction coefficient is of crucial importance for radiative transfer calculations in we… more
Date: March 6, 2012
Creator: Korolev, A; Shashkov, A & Barker, H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Case Studies Comparing System Advisor Model (SAM) Results to Real Performance Data: Preprint

Description: NREL has completed a series of detailed case studies comparing the simulations of the System Advisor Model (SAM) and measured performance data or published performance expectations. These case studies compare PV measured performance data with simulated performance data using appropriate weather data. The measured data sets were primarily taken from NREL onsite PV systems and weather monitoring stations.
Date: June 1, 2012
Creator: Blair, N.; Dobos, A. & Sather, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report. October 1 - December 31, 2010.

Description: Individual raw datastreams from instrumentation at the Atmospheric Radiation Measurement (ARM) Climate Research Facility fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near-real time. Raw and processed data are then sent approximately daily to the ARM Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of processed data records rece… more
Date: February 1, 2011
Creator: Sisterson, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Comparison of Wind Power and Load Forecasting Error Distributions: Preprint

Description: The introduction of large amounts of variable and uncertain power sources, such as wind power, into the electricity grid presents a number of challenges for system operations. One issue involves the uncertainty associated with scheduling power that wind will supply in future timeframes. However, this is not an entirely new challenge; load is also variable and uncertain, and is strongly influenced by weather patterns. In this work we make a comparison between the day-ahead forecasting errors enc… more
Date: July 1, 2012
Creator: Hodge, B. M.; Florita, A.; Orwig, K.; Lew, D. & Milligan, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

HIGH-RESOLUTION ATMOSPHERIC ENSEMBLE MODELING AT SRNL

Description: The High-Resolution Mid-Atlantic Forecasting Ensemble (HME) is a federated effort to improve operational forecasts related to precipitation, convection and boundary layer evolution, and fire weather utilizing data and computing resources from a diverse group of cooperating institutions in order to create a mesoscale ensemble from independent members. Collaborating organizations involved in the project include universities, National Weather Service offices, and national laboratories, including t… more
Date: May 10, 2011
Creator: Buckley, R.; Werth, D.; Chiswell, S. & Etherton, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Sampling Within k-Means Algorithm to Cluster Large Datasets

Description: Due to current data collection technology, our ability to gather data has surpassed our ability to analyze it. In particular, k-means, one of the simplest and fastest clustering algorithms, is ill-equipped to handle extremely large datasets on even the most powerful machines. Our new algorithm uses a sample from a dataset to decrease runtime by reducing the amount of data analyzed. We perform a simulation study to compare our sampling based k-means to the standard k-means algorithm by analyzing… more
Date: August 1, 2011
Creator: Bejarano, Jeremy; Bose, Koushiki; Brannan, Tyler; Thomas, Anita; Adragni, Kofi; Neerchal, Nagaraj et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance of "Moth Eye" Anti-Reflective Coatings for Solar Cell Applications

Description: An inexpensive, effective anti-reflective coating (ARC) has been developed at the University of Florida to significantly enhance the absorption of light by silicon in solar cells. This coating has nano-scale features, and its microstructure mimics that of various night active insects (e.g. a moth's eye). It is a square array of pillars, each about 700 nm high and having a diameter of about 300 nm. Samples of silicon having this coating were exposed either to various combinations of either eleva… more
Date: March 14, 2011
Creator: Clark, E.; Kane, M. & Jiang, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Improved Transport Processes for CCSM

Description: In atmospheric modeling, global spectral methods have dominated weather and climate simulation for the past two decades. However, global methods based upon the spherical harmonic basis functions require expensive non-local communication and thus have difficulty in exploiting the full potential of current high-performance parallel computers. The primary objective of HOMME ((11)) is the development of a class of high-order scalable conservative atmospheric models for climate and general atmospher… more
Date: May 5, 2011
Creator: Tufo, Henry
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Adaptive and Efficient Computing for Subsurface Simulation within ParFlow

Description: This project is concerned with the PF.WRF model as a means to enable more accurate predictions of wind fluctuations and subsurface storage. As developed at LLNL, PF.WRF couples a groundwater (subsurface) and surface water flow model (ParFlow) to a mesoscale atmospheric model (WRF, Weather Research and Forecasting Model). It was developed as a unique tool to address coupled water balance and wind energy questions that occur across traditionally separated research regimes of the atmosphere, land … more
Date: November 16, 2010
Creator: Tiedeman, H & Woodward, C S
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Observing System Simulation Experiments (OSSEs) for the Mid-Columbia Basin

Description: The overall goal of this multi-phased research project known as WindSENSE is to develop an observation system deployment strategy that would improve wind power generation forecasts. The objective of the deployment strategy is to produce the maximum benefit for 1- to 6-hour ahead forecasts of wind speed at hub-height ({approx}80 m). In this phase of the project the focus is on the Mid-Columbia Basin region, which encompasses the Bonneville Power Administration (BPA) wind generation area (Figure … more
Date: September 13, 2011
Creator: Zack, J; Natenberg, E J; Knowe, G V; Waight, K; Manobianco, J; Hanley, D et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Executive summary for assessing the near-term risk of climate uncertainty : interdependencies among the U.S. states.

Description: Policy makers will most likely need to make decisions about climate policy before climate scientists have resolved all relevant uncertainties about the impacts of climate change. This study demonstrates a risk-assessment methodology for evaluating uncertain future climatic conditions. We estimate the impacts of climate change on U.S. state- and national-level economic activity from 2010 to 2050. To understand the implications of uncertainty on risk and to provide a near-term rationale for polic… more
Date: April 1, 2010
Creator: Loose, Verne W.; Lowry, Thomas Stephen; Malczynski, Leonard A.; Tidwell, Vincent Carroll; Stamber, Kevin Louis; Reinert, Rhonda K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

FY 2010 Fourth Quarter Report: Evaluation of the Dependency of Drizzle Formation on Aerosol Properties

Description: Metric for Quarter 4: Report results of implementation of composite parameterization in single-column model (SCM) to explore the dependency of drizzle formation on aerosol properties. To better represent VOCALS conditions during a test flight, the Liu-Duam-McGraw (LDM) drizzle parameterization is implemented in the high-resolution Weather Research and Forecasting (WRF) model, as well as in the single-column Community Atmosphere Model (CAM), to explore this dependency.
Date: October 1, 2010
Creator: Lin, W.; McGraw, R.; Liu, Y.; Wang, J.; Vogelmann, A. & Daum, P. H.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Numerical errors in the presence of steep topography: analysis and alternatives

Description: It is well known in computational fluid dynamics that grid quality affects the accuracy of numerical solutions. When assessing grid quality, properties such as aspect ratio, orthogonality of coordinate surfaces, and cell volume are considered. Mesoscale atmospheric models generally use terrain-following coordinates with large aspect ratios near the surface. As high resolution numerical simulations are increasingly used to study topographically forced flows, a high degree of non-orthogonality is… more
Date: April 15, 2010
Creator: Lundquist, K A; Chow, F K & Lundquist, J K
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Energy and air quality implications of passive stack ventilation in residential buildings

Description: Ventilation requires energy to transport and condition the incoming air. The energy consumption for ventilation in residential buildings depends on the ventilation rate required to maintain an acceptable indoor air quality. Historically, U.S. residential buildings relied on natural infiltration to provide sufficient ventilation, but as homes get tighter, designed ventilation systems are more frequently required particularly for new energy efficient homes and retrofitted homes. ASHRAE Standard 6… more
Date: January 1, 2011
Creator: Mortensen, Dorthe Kragsig; Walker, Iain S. & Sherman, Max
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Performance of Variable Capacity Heat Pumps in a Mixed Humid Climate

Description: Variable capacity heat pumps represent the next wave of technology for heat pumps. In this report, the performance of two variable capacity heat pumps (HPs) is compared to that of a single or two stage baseline system. The units were installed in two existing research houses located in Knoxville, TN. These houses were instrumented to collect energy use and temperature data while both the baseline systems and variable capacity systems were installed. The homes had computer controlled simulated o… more
Date: April 1, 2012
Creator: Munk, Jeffrey D; Gehl, Anthony C & Jackson, Roderick K
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EFFECT OF CLIMATE CHANGE ON WATERSHED RUNOFF FLOW - UPPER COOSA RIVER BASIN UPSTREAM FROM PLANT HAMMOND

Description: The ability of water managers to maintain adequate supplies in the coming decades depends on future weather conditions, as climate change has the potential to reduce stream flows from their current values due to potentially less precipitation and higher temperatures, and possibly rendering them unable to meet demand. The upper Coosa River basin, located in northwest Georgia, plays an important role in supplying water for industry and domestic use in northern Georgia, and has been involved in wa… more
Date: October 24, 2011
Creator: Chen, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Weather-Corrected Performance Ratio

Description: Photovoltaic (PV) system performance depends on both the quality of the system and the weather. One simple way to communicate the system performance is to use the performance ratio (PR): the ratio of the electricity generated to the electricity that would have been generated if the plant consistently converted sunlight to electricity at the level expected from the DC nameplate rating. The annual system yield for flat-plate PV systems is estimated by the product of the annual insolation in the p… more
Date: April 1, 2013
Creator: Dierauf, T.; Growitz, A.; Kurtz, S.; Cruz, J. L. B.; Riley, E. & Hansen, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Habitat-based Wind-Wildlife Collision Model with Application to the Upper Great Plains Region

Description: Most previous studies on collision impacts at wind facilities have taken place at the site-specific level and have only examined small-scale influences on mortality. In this study, we examine landscape-level influences using a hierarchical spatial model combined with existing datasets and life history knowledge for: Horned Lark, Red-eyed Vireo, Mallard, American Avocet, Golden Eagle, Whooping Crane, red bat, silver-haired bat, and hoary bat. These species were modeled in the central United Stat… more
Date: August 28, 2012
Creator: Forcey, Greg, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tracking tropical cloud systems - Observations for the diagnosis of simulations by the Weather Research and Forecasting (WRF) Model

Description: To aid in improving model parameterizations of clouds and convection, we examine the capability of models, using explicit convection, to simulate the life cycle of tropical cloud systems in the vicinity of the ARM Tropical Western Pacific sites. The cloud life cycle is determined using a satellite cloud tracking algorithm (Boer and Ramanathan, 1997), and the statistics are compared to those of simulations using the Weather Research and Forecasting (WRF) Model. Using New York Blue, a Blue Gene/L… more
Date: March 15, 2010
Creator: Vogelmann, A.M.; Lin, W.; Cialella, A.; Luke, E.; Jensen, M. & Zhang, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A comparison of cloud microphysical quantities with forecasts from cloud prediction models

Description: Numerical weather prediction models (ECMWF, NCEP) are evaluated using ARM observational data collected at the Southern Great Plains (SGP) site. Cloud forecasts generated by the models are compared with cloud microphysical quantities, retrieved using a variety of parameterizations. Information gained from this comparison will be utilized during the FASTER project, as models are evaluated for their ability to reproduce fast physical processes detected in the observations. Here the model performan… more
Date: March 15, 2010
Creator: Dunn, M.; Jensen, M.; Hogan, R.; O’Connor, E. & Huang, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Fast Physics Testbed for the FASTER Project

Description: This poster describes the Fast Physics Testbed for the new FAst-physics System Testbed and Research (FASTER) project. The overall objective is to provide a convenient and comprehensive platform for fast turn-around model evaluation against ARM observations and to facilitate development of parameterizations for cloud-related fast processes represented in global climate models. The testbed features three major components: a single column model (SCM) testbed, an NWP-Testbed, and high-resolution mo… more
Date: March 15, 2010
Creator: Lin, W.; Liu, Y.; Hogan, R.; Neggers, R.; Jensen, M.; Fridlind, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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