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From page 13... ... 13 3 Evaluation of Data Sources 3.1 Introduction In this section, we identify and evaluate potential sources of spatiotemporal population distribution data that could be utilized for aviation noise studies. While the focus of our evaluation was on diurnal movement, we also investigated any population data that has a temporal aspect -- be it for smaller increments of the day or for seasonal movements. Read the entire page →
From page 14... ... 14 • Category 3: High-resolution location data that is based on emerging technologies such as cell tower triangulation or device-recorded GPS positions. The basis for the comparison of these data sets is the current baseline of the decennial U.S. Read the entire page →
From page 15... ... 15 3.2.3 Data Applicability Our initial evaluation of the ACS data suggests that they are not at a level of resolution and fidelity that can be immediately useful for aviation noise studies. Since aviation noise studies typically utilize census block points, the resampling of ACS county-level daytime values would almost certainly result in excessive smoothing and over-simplification. Read the entire page →
From page 16... ... 16 Figure 3: LODES Movement for the City of San Francisco 3.3.1 Data Availability It does not cost anything to obtain and download LODES data from the Census website. Data are available by version (version 7 is enumerated by 2010 census blocks and earlier versions are enumerated by the 2000 census blocks) Read the entire page →
From page 17... ... 17 moving from their home blocks to other blocks for work and about 1.8 million persons moving to blocks inside the analysis area for work. Even taking into account non-workers (e.g., tourists, children, and volunteers) Read the entire page →
From page 18... ... 18 3.4.2 Data Quality The LandScan algorithm uses spatial data and imagery analysis technologies and a multi-variable dasymetric modeling approach to disaggregate census counts within administrative boundaries. Based upon the spatial data and the socioeconomic and cultural understanding of an area, cells are preferentially weighted for the possible occurrence of population during a day. Read the entire page →
From page 19... ... 19 Figure 4: LandScan Cells and Centroids Overlaid on Census Block Centroids 3.4.3 Data Applicability Researchers at ORNL have employed detailed research, imagery, analysis, and modeling techniques to develop the LandScan data set from the base census data. The result is a sophisticated derivative of the census population representing the ambient 24-hour distribution. Read the entire page →
From page 20... ... 20 3.4.5 Conclusions The LandScan data set represents the cutting edge of spatiotemporal population distribution development. The development of the data encompasses diurnal movement, weekend movement, and even seasonal movement. Read the entire page →
From page 21... ... 21 The data set for the U.S. is a rasterized 3-arc second grid (about 90 meters square) Read the entire page →
From page 22... ... 22 3.5.4 Data Compatibility The LandScan USA data set is at a resolution that is probably suitable for use as-is with aviation noise studies. Since the data set contains both a daytime layer and a nighttime layer, if desired it can also be resampled onto census block centroids to be used for standard noise studies that use census block points. Read the entire page →
From page 23... ... 23 3.6.1 Data Availability The daytime population data set is available as a single data set for the entire U.S. for a cost of $800. Read the entire page →
From page 24... ... 24 can be resampled to finer grain census block points. Lastly, the cost to obtain the data set is quite reasonable and should be affordable to most aviation noise practitioners. Read the entire page →
From page 25... ... 25 3.7.3 Data Applicability At the appropriate resolution, e.g., 10 meters or 100 meters, the Activity Density data set can be used to develop fairly accurate spatiotemporal distributions of population for different times of the day, week, and year. These data could be transformed into population centroids at a resolution much better than anything currently used for aviation noise modeling. Read the entire page →
From page 26... ... 26 ACS and LODES, provided by the U.S. Census Bureau, are two free sources of data that we evaluated. Read the entire page →
From page 27... ... 27 Figure 8: Census 2010 Population (left) and Resampled LandScan data (right) Read the entire page →

From page 13...

... 13 3 Evaluation of Data Sources 3.1 Introduction In this section, we identify and evaluate potential sources of spatiotemporal population distribution data that could be utilized for aviation noise studies. While the focus of our evaluation was on diurnal movement, we also investigated any population data that has a temporal aspect -- be it for smaller increments of the day or for seasonal movements.