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Existing climate data sources and Their Use in Heat IslandResearch

Description: Existing climate data sources can be used in two general types of analysis for the detection of urban heat islands. Historical analyses use long-term data records-preferentially from several locations in and around an urban area-to trace the gradual influence of urban development on its climate. Primary sources of such data include the cooperative network, first-order National Weather Service stations, and military weather stations. Analyses of short-term data use information from a dense urban weather station network to discern the location, extent, and magnitude of urban heat islands. Such analyses may use the aforementioned national networks or regional networks such as agricultural, air quality monitoring, or utility networks. We demonstrate the use of existing data sources with a historical analysis of temperature trends in Los Angeles, California, and an analysis of short-term data of the urban temperature profile for Phoenix, Arizona. The Los Angeles climate was examined with eleven long-term data records from the cooperative network. Statistically significant trends of rising temperature were detected at Los Angeles Civic Center and other stations over some parts of the year, although timing of the increase varied from station to station. Observed increases in temperatures maybe due to long-term climate changes, microclimate influences, or local-scale heat islands. The analysis of short-term data was made for Phoenix using the PRISMS station network. Mean diurnal temperature profiles for a month were examined and compared with those for adjacent rural areas. Data fi-om stations in the center of Phoenix showed clear and significant nighttime and daytime temperature differences of 1- 2K (3 - 4"F). These temperature increases maybe attributable to a local-scale heat island.
Date: October 1, 1998
Creator: Akbari, Hashem; Pon, Brian; Smith, Craig Kenton & Stamper-Kurn, Dan Moses
Partner: UNT Libraries Government Documents Department

Characterizing the Fabric of the Urban Environment: A Case Study of Sacramento, California

Description: To estimate the impact of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on meteorology and air quality of a city, it is essential to accurately estimate the fraction of various urban surfaces. In this report, we estimate the fabric of Sacramento by analyzing high-resolution (0.30-m) aerial color photographs of about 65 square km of the urban area. The analysis show that in downtown Sacramento, vegetation as seen from above the canopy covers 30% of the area, whereas roofs cover 23% and paved surface 41%. Under-the-canopy fabric consists of 52% paved surfaces, 26% roofs, and 12% grass. In the industrial areas, vegetation covers 8-14% of the area, roofs cover 19-23%, and paved surfaces cover 29-44%. The surface-type percentages in the office areas are 21% trees, 16% roofs, and 49% paved surfaces. In commercial areas,vegetation covers 5-20%, roofs 19-20%, paved surfaces 44-68%. Residential areas exhibit a wide range of percentages of surface-types . On average, vegetation covers about 36% of the area, roofs cover about 20%, and paved surfaces about 28%. Trees mostly shade streets, parking lots, grass, and sidewalks. Under the canopy the percentage of paved surfaces is significantly higher. In most non-residential areas, paved surfaces cover 50-70% of the area. In residential areas, on average, paved surfaces cover about 35% of the area. For an area of roughly 800 sq. km, defining most of metropolitan Sacramento, about half is residential. The total roof area is about 150 sq. km and the total paved surfaces (roads, parking areas, sidewalks) is about 310 sq. km. The total vegetated area is about 230 sq. km.
Date: December 1, 1999
Creator: Akbari, Hashen; Rose, L. Shea & Taha, Haider
Partner: UNT Libraries Government Documents Department

Global Cooling: Effect of Urban Albedo on Global Temperature

Description: In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). The roof and the pavement albedo can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60%. We estimate U.S. potential savings in excess of $1 billion (B) per year in net annual energy bills. Increasing albedo of urban surfaces can reduce the summertime urban temperature and improve the urban air quality. Increasing the urban albedo has the added benefit of reflecting more of the incoming global solar radiation and countering the effect of global warming. We estimate that increasing albedo of urban areas by 0.1 results in an increase of 3 x 10{sup -4} in Earth albedo. Using a simple global model, the change in air temperature in lowest 1.8 km of the atmosphere is estimated at 0.01K. Modelers predict a warming of about 3K in the next 60 years (0.05K/year). Change of 0.1 in urban albedo will result in 0.01K global cooling, a delay of {approx}0.2 years in global warming. This 0.2 years delay in global warming is equivalent to 10 Gt reduction in CO2 emissions.
Date: May 22, 2007
Creator: Akbari, Hashem; Menon, Surabi & Rosenfeld, Arthur
Partner: UNT Libraries Government Documents Department

Urban Consortium Energy Task Force - Year 21 Final Report

Description: The Urban Consortium Energy Task Force (UCETF), comprised of representatives of large cities and counties in the United States, is a subgroup of the Urban Consortium, an organization of the nation's largest cities and counties joined together to identify, develop and deploy innovative approaches and technological solutions to pressing urban issues.
Date: April 1, 2003
Partner: UNT Libraries Government Documents Department

An Improved WRF for Urban-Scale and Complex-Terrain Applications

Description: Simulations of atmospheric flow through urban areas must account for a wide range of physical phenomena including both mesoscale and urban processes. Numerical weather prediction models, such as the Weather and Research Forecasting model (WRF), excel at predicting synoptic and mesoscale phenomena. With grid spacings of less than 1 km (as is required for complex heterogeneous urban areas), however, the limits of WRF's terrain capabilities and subfilter scale (SFS) turbulence parameterizations are exposed. Observations of turbulence in urban areas frequently illustrate a local imbalance of turbulent kinetic energy (TKE), which cannot be captured by current turbulence models. Furthermore, WRF's terrain-following coordinate system is inappropriate for high-resolution simulations that include buildings. To address these issues, we are implementing significant modifications to the ARW core of the Weather Research and Forecasting model. First, we are implementing an improved turbulence model, the Dynamic Reconstruction Model (DRM), following Chow et al. (2005). Second, we are modifying WRF's terrain-following coordinate system by implementing an immersed boundary method (IBM) approach to account for the effects of urban geometries and complex terrain. Companion papers detailing the improvements enabled by the DRM and the IBM approaches are also presented (by Mirocha et al., paper 13.1, and K.A. Lundquist et al., paper 11.1, respectively). This overview of the LLNL-UC Berkeley collaboration presents the motivation for this work and some highlights of our progress to date. After implementing both DRM and an IBM for buildings in WRF, we will be able to seamlessly integrate mesoscale synoptic boundary conditions with building-scale urban simulations using grid nesting and lateral boundary forcing. This multi-scale integration will enable high-resolution simulations of flow and dispersion in complex geometries such as urban areas, as well as new simulation capabilities in regions of complex terrain.
Date: September 4, 2007
Creator: Lundquist, J K; Chow, F K; Mirocha, J D & Lundquist, K A
Partner: UNT Libraries Government Documents Department

Analysis of sheltering and evacuation strategies for a Chicago nuclear detonation scenario.

Description: Development of an effective strategy for shelter and evacuation is among the most important planning tasks in preparation for response to a low yield, nuclear detonation in an urban area. Extensive studies have been performed and guidance published that highlight the key principles for saving lives following such an event. However, region-specific data are important in the planning process as well. This study examines some of the unique regional factors that impact planning for a 10 kt detonation in Chicago. The work utilizes a single scenario to examine regional impacts as well as the shelter-evacuate decision alternatives at selected exemplary points. For many Chicago neighborhoods, the excellent assessed shelter quality available make shelter-in-place or selective transit to a nearby shelter a compelling post-detonation strategy.
Date: September 1, 2011
Creator: Yoshimura, Ann S. & Brandt, Larry D.
Partner: UNT Libraries Government Documents Department

Analysis of sheltering and evacuation strategies for a national capital region nuclear detonation scenario.

Description: Development of an effective strategy for shelter and evacuation is among the most important planning tasks in preparation for response to a low yield, nuclear detonation in an urban area. Extensive studies have been performed and guidance published that highlight the key principles for saving lives following such an event. However, region-specific data are important in the planning process as well. This study examines some of the unique regional factors that impact planning for a 10 kT detonation in the National Capital Region. The work utilizes a single scenario to examine regional impacts as well as the shelter-evacuate decision alternatives at one exemplary point. For most Washington, DC neighborhoods, the excellent assessed shelter quality available make shelter-in-place or selective transit to a nearby shelter a compelling post-detonation strategy.
Date: December 1, 2011
Creator: Yoshimura, Ann S. & Brandt, Larry D.
Partner: UNT Libraries Government Documents Department

Southern Fine Particulate Monitoring Project

Description: This final project report presents experimental details, results and analysis of continuous onsite ambient fine particulate data at the North Birmingham sampling site during the October, 2001-September, 2002 study period.The host site for these measurement activities is the North Birmingham PM monitoring station by the Jefferson County Health Department in Birmingham, AL.The continuous data include PM{sub 2.5} mass concentrations measured by TEOM, particle sulfate using the R&P 8400S monitor, particle size distributions measured by SMPS and APS monitors, and PM{sub 2.5} light scattering extinction coefficient as measured by nephelometer. During the course of the project, measurement intercomparison data were developed for these instruments and several complementary measurements at the site. The report details the instrument set and operating procedures and describes the resulting data. Report subsections present an overview summary of the data, followed by detailed description of the systematic time behavior of PM{sub 2.5} and other specific particulate size fractions. Specific subsections are included for particle size distribution, light scattering, and particle sulfate data. The final subsection addresses application of the measurements to the practical questions of fine PM generation and transport, source attribution, and PM{sub 2.5} management strategies.
Date: May 31, 2003
Creator: Williamson, Ashley
Partner: UNT Libraries Government Documents Department

Evaluation of an urban vegetative canopy scheme and impact on plume dispersion

Description: The Quick Urban and Industrial Complex (QUIC) atmospheric dispersion modeling system attempts to fill an important gap between the fast, but nonbuilding-aware Gaussian plume models and the building-aware but slow computational fluid dynamics (CFD) models. While Gaussian models have the ability to give answers quickly to emergency responders, they are unlikely to be able to adequately account for the effects of the building-induced complex flow patterns on the near-source dispersion of contaminants. QUIC uses a diagnostic massconsistent empirical wind model called QUIC-URB that is based on the methodology of Rockle (1990), (see also Kaplan and Dinar 1996). In this approach, the recirculation zones that form around and between buildings are inserted into the flow using empirical parameterizations and then the wind field is forced to be mass consistent. Although not as accurate as CFD codes, this approach is several orders of magnitude faster and accounts for the bulk effects of buildings.
Date: January 1, 2009
Creator: Nelson, Matthew A; Williams, Michael D; Zajic, Dragan; Brown, Michael J & Pardyjak, Eric R
Partner: UNT Libraries Government Documents Department

A shallow water model for dense gas simulation in urban areas

Description: Large quantities of toxic chemicals are stored at industrial facilities and transported around the country via train and truck. In the event of an accidental release, many of these chemicals are released as heavier-than-air gases that stay low to the ground as they are transported by the wind . Breathing height concentrations can remain high due to reduced vertical mixing and hazard zone coverage area can be larger due to near-source gravitational slumping . A number of fast-response dense gas dispersion models have been developed and are routinely used to deal with heavier-than-air releases over unobstructed terrain. If a release were to occur in a built-up environment, however, the effects of buildings and other obstacles will significantly alter the initial spreading, the transport direction, and the amount of mixing of the dense gas cloud . We have developed a new fast-running dense gas dispersion model that is intended for handling releases in cities and at large industrial facilities. In this paper we describe the scheme employed and how the model has been integrated into the Quick Urban & Industrial Complex (QUIC) dispersion modeling system.
Date: January 1, 2009
Creator: Brown, Michael; Williams, Mike D; Gowardhan, Akshay; Brambilla, Sara & Manca, Davide
Partner: UNT Libraries Government Documents Department

IBRD Operational Decision Framework

Description: The IBRD Operational Decision Framework in this document is an expansion of an emerging general risk management framework under development by an interagency working group. It provides the level of detail necessary to develop a general Consequence Management Guidance Document for biological contamination remediation and restoration. It is the intent of this document to support both wide area and individual site remediation and restoration activities. This product was initiated as a portion of the IBRD Task 1 Systems Analysis to aid in identification of wide area remediation and restoration shortcomings and gaps. The draft interagency general risk management framework was used as the basis for the analysis. The initial Task 1 analysis document expanded the draft interagency framework to a higher level of resolution, building on both the logic structure and the accompanying text explanations. It was then employed in a qualitative manner to identify responsible agencies, data requirements, tool requirements, and current capabilities for each decision and task. This resulted in identifying shortcomings and gaps needing resolution. Several meetings of a joint LLNL/SNL working group reviewed and approved the initial content of this analysis. At the conclusion of Task 1, work continued on the expanded framework to generate this Operational Decision Framework which is consistent with the existing interagency general risk management framework. A large LLNL task group met repeatedly over a three-month period to develop the expanded framework, coordinate the framework with the biological remediation checklist, and synchronize the logic with the Consequence Management Plan table of contents. The expanded framework was briefed at a large table top exercise reviewing the interagency risk management framework. This exercise had representation from major US metropolitan areas as well as national agencies. This product received positive comments from the participants. Upon completion of the Operational Decision Framework, another joint LLNL/SNL working ...
Date: November 12, 2010
Creator: Greenwalt, R; Hibbard, W; Raber, E; Carlsen, T; Folks, K; MacQueen, D et al.
Partner: UNT Libraries Government Documents Department

Scaling up of Carbon Exchange Dynamics from AmeriFlux Sites to a Super-Region in the Eastern United States

Description: The primary objective of this project was to evaluate carbon exchange dynamics across a region of North America between the Great Plains and the East Coast. This region contains about 40 active carbon cycle research (AmeriFlux) sites in a variety of climatic and landuse settings, from upland forest to urban development. The core research involved a scaling strategy that uses measured fluxes of CO{sub 2}, energy, water, and other biophysical and biometric parameters to train and calibrate surface-vegetation-atmosphere models, in conjunction with satellite (MODIS) derived drivers. To achieve matching of measured and modeled fluxes, the ecosystem parameters of the models will be adjusted to the dynamically variable flux-tower footprints following Schmid (1997). High-resolution vegetation index variations around the flux sites have been derived from Landsat data for this purpose. The calibrated models are being used in conjunction with MODIS data, atmospheric re-analysis data, and digital land-cover databases to derive ecosystem exchange fluxes over the study domain.
Date: May 5, 2009
Creator: Schmid, Hans Peter & Wayson, Craig
Partner: UNT Libraries Government Documents Department

Radiative forcing and temperature response to changes in urban albedos and associated CO2 offsets

Description: The two main forcings that can counteract to some extent the positive forcings from greenhouse gases from pre-industrial times to present-day are the aerosol and related aerosol-cloud forcings, and the radiative response to changes in surface albedo. Here, we quantify the change in radiative forcing and land surface temperature that may be obtained by increasing the albedos of roofs and pavements in urban areas in temperate and tropical regions of the globe by 0.1. Using the catchment land surface model (the land model coupled to the GEOS-5 Atmospheric General Circulation Model), we quantify the change in the total outgoing (outgoing shortwave+longwave) radiation and land surface temperature to a 0.1 increase in urban albedos for all global land areas. The global average increase in the total outgoing radiation was 0.5 Wm{sup -2}, and temperature decreased by {approx}0.008 K for an average 0.003 increase in surface albedo. These averages represent all global land areas where data were available from the land surface model used and are for the boreal summer (June-July-August). For the continental U.S. the total outgoing radiation increased by 2.3 Wm{sup -2}, and land surface temperature decreased by {approx}0.03 K for an average 0.01 increase in surface albedo. Based on these forcings, the expected emitted CO{sub 2} offset for a plausible 0.25 and 0.15 increase in albedos of roofs and pavements, respectively, for all global urban areas, was found to be {approx} 57 Gt CO{sub 2}. A more meaningful evaluation of the impacts of urban albedo increases on global climate and the expected CO{sub 2} offsets would require simulations which better characterizes urban surfaces and represents the full annual cycle.
Date: February 12, 2010
Creator: Menon, Surabi; Akbari, Hashem; Mahanama, Sarith; Sednev, Igor & Levinson, Ronnen
Partner: UNT Libraries Government Documents Department

The effect of microscale urban canyon flow on mesoscale puff dispersion

Description: When modeling mesoscale plume or puff transport over distances of one to ten kilometers, the initial small-scale near-source effects are often ignored or parameterized in a crude way. If the release is in an urban environment, buildings and other urban structures can significantly impact the local plume dispersion (e.g., Davidson et al., 1995). In this paper, the authors investigate whether the building-scale effects are important on the longer time-scale mesoscale dispersion process.
Date: June 1, 1997
Creator: Brown, M.J. & Muller, C.
Partner: UNT Libraries Government Documents Department

Chicago metropolitan area critical infrastructure protection program critical infrastructure assurance guidelines for municipal governments planning for natural gas disruptions.

Description: This document presents guidelines on actions that can be taken by municipal governments to protect public health and safety before, during, and after disruptions to natural gas service. This type of planning and preparation, referred to as ''critical infrastructure assurance,'' gives communities the ability to prevent or reduce serious impacts associated with critical infrastructure disruptions.
Date: February 21, 2003
Creator: Cirillo, R.
Partner: UNT Libraries Government Documents Department

Formal evaluation of the ADVANCE targeted deployment

Description: The Advanced Driver and Vehicle Advisory Navigation Concept (ADVANCE) advanced traveler information system (ATIS) demonstration project in northeastern Illinois was re-scoped in late 1994 from its originally-planned deployment of 3,000--5,000 in-vehicle navigation units to a so-called ``targeted`` deployment in which up to 75 vehicles were equipped with devices enabling them to receive real-time traffic information. These devices included (1) global positioning system (GPS) transmitters/receivers that enabled the vehicles while in the ADVANCE study area to serve as dynamic traffic probes as well as recipients of location data; and (2) navigation units that employed a comprehensive map data base and average (static) link travel times by time of day, stored on CD-ROM, which together computed efficient (least duration) routes between any origin and destination in the northwest portion of the Chicago metropolitan area. Experiments were designed to dispatch these equipped vehicles along links at headways or frequencies comparable to what would have been observed had full deployment actually occurred. Thus, within the limitations of this controlled environment, valuative experiments were conducted to assess the quality of several of the key sub-systems of ADVANCE in the context of structured performance hypotheses. Focused on-road tests began on June 1 and continued through December 14, 1995, followed by a period of data evaluation, documentation of results, and development of conclusions about the findings and usefulness of the project. This paper describes the tests, discusses development of the overall evaluation plan and the evaluation management concept which guided them, and reports on issuses and results of data analysis known at time of writing.
Date: April 1, 1996
Creator: Saricks, C.L.; Belella, P.A.; Koppelman, F.S.; Schofer, J.L. & Sen, A.K.
Partner: UNT Libraries Government Documents Department

Societal health and urban sustainability indicators

Description: Without the social will, no city can successfully Undertake the planning and programs necessary for meaningful progress toward sustainability. Social will derives from wellsprings of vital societal health. This paper presents an approach to helping cities in APEC member economies initiate a program for developing indicators of sustainability. Representative indicators of social capital and other aspects of civic engagement, as proxies for societal health, are presented.
Date: August 27, 1996
Creator: Petrich, C.H. & Tonn, B.E.
Partner: UNT Libraries Government Documents Department

Pollutant transfer through air and water pathways in an urban environment

Description: The authors are attempting to simulate the transport and fate of pollutants through air and water pathways in an urban environment. This cross-disciplinary study involves linking together models of mesoscale meteorology, air pollution chemistry and deposition, urban runoff and stormwater transport, water quality, and wetland chemistry and biology. The authors are focusing on the transport and fate of nitrogen species because (1) they track through both air and water pathways, (2) the physics, chemistry, and biology of the complete cycle is not well understood, and (3) they have important health, local ecosystem, and global climate implications. The authors will apply their linked modeling system to the Los Angeles basin, following the fate of nitrates from their beginning as nitrate-precursors produced by auto emissions and industrial processes, tracking their dispersion and chemistry as they are transported by regional winds and eventually wet or dry deposit on the ground, tracing their path as they are entrained into surface water runoff during rain events and carried into the stormwater system, and then evaluating their impact on receiving water bodies such as wetlands where biologically-mediated chemical reactions take place. In this paper, the authors wish to give an overview of the project and at the conference show preliminary results.
Date: December 31, 1998
Creator: Brown, M.; Burian, S.; McPherson, T.; Streit, G.; Costigan, K. & Greene, B.
Partner: UNT Libraries Government Documents Department

Industrial ecology at Lawrence Livermore National Laboratory summary statement

Description: This statement summarizes Lawrence Livermore National Laboratory`s committment to making important scientific, technological, and business contributions to global sustainability. The quest has many aspects, some socio-political or economic and some technological, and some in which the soft and hard sciences become indistinguishable, as in visionary national strategies, like Holland`s, and futuristic regional and city development plans, like those of Kagoshima and Chattanooga.
Date: May 21, 1996
Creator: Gilmartin, T.J.
Partner: UNT Libraries Government Documents Department