How can GIS analysis identify areas with poor transportation access?

1 What is GIS analysis?

GIS analysis is the process of using spatial data, tools, and methods to answer questions, solve problems, and support decision-making in various fields and applications. GIS analysis can involve data collection, processing, visualization, manipulation, modeling, and interpretation. For example, you can use GIS analysis to create maps that show the distribution of population, income, land use, or environmental factors in a region. You can also use GIS analysis to perform calculations, such as distance, area, density, or network analysis, that reveal patterns, trends, or relationships among spatial data. Furthermore, you can use GIS analysis to evaluate scenarios, such as the impact of a new road, transit line, or bike lane on travel behavior, accessibility, or equity.

2 How can GIS analysis map transportation access?

One of the first steps in using GIS analysis to identify areas with poor transportation access is to map the existing transportation system and the potential destinations that people need or want to reach. The transportation system can include roads, railways, bus routes, bike paths, sidewalks, or any other infrastructure that enables mobility. The potential destinations can include workplaces, schools, health facilities, shopping centers, parks, or any other places that provide opportunities or services. By mapping the transportation system and the potential destinations, you can visualize the spatial distribution and connectivity of both supply and demand for transportation in a region.

3 How can GIS analysis measure transportation access?

The next step in using GIS analysis to identify areas with poor transportation access is to measure the level of access that different groups of people have to various destinations. To do this, there are various methods and indicators that can be used, depending on the purpose and scope of the analysis. For example, travel time can be estimated using network analysis to calculate the shortest or fastest route along the transportation system, taking into account factors such as speed, traffic, or frequency. Travel cost can include monetary expenses, such as fuel, parking, or fares, as well as non-monetary costs like environmental impacts or health risks. Additionally, travel mode can be estimated using data sources like mode share or transit coverage. Finally, travel quality can include factors such as road condition or transit frequency. All of these measures can be used to compare accessibility, affordability, attractiveness and satisfaction of different modes or locations and define thresholds or standards for acceptable levels.

4 How can GIS analysis evaluate transportation access?

The final step in using GIS analysis to identify areas with poor transportation access is to evaluate the current or future situation of transportation access in a region, and to identify the gaps, needs, or opportunities for improvement. There are different methods and techniques that can be used to evaluate transportation access, depending on the objective and criteria of the analysis. For example, spatial analysis can be used to create heat maps, choropleth maps, or isochrone maps that visualize the variation of transportation access across a region. Additionally, statistical analysis can calculate descriptive statistics such as mean, median, or standard deviation that summarize the characteristics of transportation access. Furthermore, scenario analysis can project or assess the impact of different scenarios or alternatives on transportation access. All these methods and techniques can help identify areas with poor transportation access and provide valuable insights for improvement.

5 Here’s what else to consider

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