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Characterizing the Evolution of Indian Cities using Satellite - - PowerPoint PPT Presentation

Characterizing the Evolution of Indian Cities using Satellite Imagery and Open Street Maps Chahat Bansal , Aditi Singla, Ankit Kumar Singh, Hari Om Ahlawat, Mayank Jain, Prachi Singh, Prashant Kumar, Ritesh Saha, Sakshi Taparia, Shailesh Yadav,


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Characterizing the Evolution of Indian Cities using Satellite Imagery and Open Street Maps

Chahat Bansal, Aditi Singla, Ankit Kumar Singh, Hari Om Ahlawat, Mayank Jain, Prachi Singh, Prashant Kumar, Ritesh Saha, Sakshi Taparia, Shailesh Yadav, and Aaditeshwar Seth

COMPASS 2020 School of Information Technology, Indian Institute of Technology- Delhi JUNE 16, 2020

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Faces of Urbanization

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Faces of Urbanization

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Faces of Urbanization

High rises and formally developed regions

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Faces of Urbanization

Informal developments in the form of urban slums

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Faces of Urbanization

Different segments of urban areas have different sustainability problems associated with them It is, therefore, important to understand the urbanization patterns of cities to improve future urban planning

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Indicators for Quantifying Urbanization

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Indicators for Quantifying Urbanization

Density of Construction

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Indicators for Quantifying Urbanization

Density of Construction Formally vs Informally Developed Settlements

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Other indicators include Area Under Construction, Urban Mobility, Population living in Urban Slums, Proportion of Urban Population with Access to Improved Health Services, etc.

Indicators for Quantifying Urbanization

Density of Construction Formally vs Informally Developed Settlements

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Indicators for Quantifying Urbanization

Such indicators have traditionally been computed through data obtained from field surveys, censuses, topographic maps, city master plans, etc.

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These datasets are, however, not uniformly available, which makes it difficult to conduct standardized comparisons between cities.

Indicators for Quantifying Urbanization

Such indicators have traditionally been computed through data obtained from field surveys, censuses, topographic maps, city master plans, etc.

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These datasets are, however, not uniformly available, which makes it difficult to conduct standardized comparisons between cities.

Indicators for Quantifying Urbanization

Such indicators have traditionally been computed through data obtained from field surveys, censuses, topographic maps, city master plans, etc.

WE PROPOSE TO ADDRESS THIS GAP

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Related Studies

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Related Studies

Several individual studies have used Satellite Images to study the urbanization pattern

  • f Indian cities like Bangalore [1], Kolkata [2], Mumbai [3], Chennai [4], and even Pune [5]

[1] Harini Nagendra, Suparsh Nagendran, Somajita Paul, and Sajid Pareeth. 2012. Graying, greening and fragmentation in the rapidly expanding Indian city of Bangalore. Landscape and Urban Planning. [2] Basu Bhatta. 2009. Analysis of urban growth pattern using remote sensing and GIS: a case study of Kolkata, India. International Journal of Remote Sensing [3] Hossein Shafizadeh Moghadam and Marco Helbich. 2013. Spatiotemporal urbanization processes in the megacity of Mumbai, India: A Markov chains-cellular automata urban growth

  • model. Applied Geography.

[4] Bharath H Aithal and TV Ramachandra. 2016. Visualization of urban growth pattern in Chennai using geoinformatics and spatial metrics. Journal of the Indian Society of Remote Sensing. [5] Lakshmi N Kantakumar, Shamita Kumar, and Karl Schneider. 2016. Spatiotemporal urban expansion in Pune metropolis, India using remote sensing. Habitat International.

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Related Studies

Several individual studies have used Satellite Images to study the urbanization pattern of Indian cities like Bangalore [1], Kolkata [2], Mumbai [3], Chennai [4], and even Pune [5]

[1] Harini Nagendra, Suparsh Nagendran, Somajita Paul, and Sajid Pareeth. 2012. Graying, greening and fragmentation in the rapidly expanding Indian city of Bangalore. Landscape and Urban Planning. [2] Basu Bhatta. 2009. Analysis of urban growth pattern using remote sensing and GIS: a case study of Kolkata, India. International Journal of Remote Sensing. [3] Hossein Shafizadeh Moghadam and Marco Helbich. 2013. Spatiotemporal urbanization processes in the megacity of Mumbai, India: A Markov chains-cellular automata urban growth

  • model. Applied Geography.

[4] Bharath H Aithal and TV Ramachandra. 2016. Visualization of urban growth pattern in Chennai using geoinformatics and spatial metrics. Journal of the Indian Society of Remote Sensing. [5] Lakshmi N Kantakumar, Shamita Kumar, and Karl Schneider. 2016. Spatiotemporal urban expansion in Pune metropolis, India using remote sensing. Habitat International.

However, these city-specific studies make it difficult to compare different cities with

  • ne another
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Related Studies

Several individual studies have used Satellite Images to study the urbanization pattern of Indian cities like Bangalore [1], Kolkata [2], Mumbai [3], Chennai [4], and even Pune [5] However, these city-specific studies make it difficult to compare different cities with one another Further, these studies look into the transition of cities over longer timescales (ten years or more)

[1] Harini Nagendra, Suparsh Nagendran, Somajita Paul, and Sajid Pareeth. 2012. Graying, greening and fragmentation in the rapidly expanding Indian city of Bangalore. Landscape and Urban Planning. [2] Basu Bhatta. 2009. Analysis of urban growth pattern using remote sensing and GIS: a case study of Kolkata, India. International Journal of Remote Sensing. [3] Hossein Shafizadeh Moghadam and Marco Helbich. 2013. Spatiotemporal urbanization processes in the megacity of Mumbai, India: A Markov chains-cellular automata urban growth

  • model. Applied Geography.

[4] Bharath H Aithal and TV Ramachandra. 2016. Visualization of urban growth pattern in Chennai using geoinformatics and spatial metrics. Journal of the Indian Society of Remote Sensing. [5] Lakshmi N Kantakumar, Shamita Kumar, and Karl Schneider. 2016. Spatiotemporal urban expansion in Pune metropolis, India using remote sensing. Habitat International.

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Related Studies

The road infrastructure in different neighborhoods can provide useful information about how well planned and developed these neighborhoods are [1]

[1] Patrick Lamson-Hall, Shlomo Angel, Alejandro Blei, Manuel Madrid, and Nicolas Galarza. 2016. The Quality of Urban Layouts.

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Related Studies

The road infrastructure in different neighborhoods can provide useful information about how well planned and developed these neighborhoods are [1] Although publicly available satellite data can be used for land-use classification, it is not of a sufficiently high resolution to detect roads [2]

[1] Patrick Lamson-Hall, Shlomo Angel, Alejandro Blei, Manuel Madrid, and Nicolas Galarza. 2016. The Quality of Urban Layouts. [2] Gabriel Cadamuro, Aggrey Muhebwa, and Jay Taneja. 2019. Street smarts: measuring intercity road quality using deep learning on satellite imagery. In Proceedings of the 2nd ACM SIGCAS Conference on Computing and Sustainable Societies.

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Related Studies

The road infrastructure in different neighborhoods can provide useful information about how well planned and developed these neighborhoods are [1] Although publicly available satellite data can be used for land-use classification, it is not

  • f a sufficiently high resolution to detect roads [2]

[1] Patrick Lamson-Hall, Shlomo Angel, Alejandro Blei, Manuel Madrid, and Nicolas Galarza. 2016. The Quality of Urban Layouts. [2] Gabriel Cadamuro, Aggrey Muhebwa, and Jay Taneja. 2019. Street smarts: measuring intercity road quality using deep learning on satellite imagery. In Proceedings of the 2nd ACM SIGCAS Conference on Computing and Sustainable Societies. [3] Jamal Jokar Arsanjani, Peter Mooney, Alexander Zipf, and Anne Schauss. 2015. Quality assessment of the contributed land use information from OpenStreetMap versus authoritative

  • datasets. In OpenStreetMap in GIScience. Springer.

[4] Mohsen Kalantari and Veha La. 2015. Assessing OpenStreetMap as an open property map. In OpenStreetMap in GIScience. Springer. [5] Jorge Gil. 2015. Building a multimodal urban network model using OpenStreetMap data for the analysis of sustainable accessibility. In OpenStreetMap in GIScience. Springer.

Our novel contribution lies in building a method to use data from Open Street Maps to develop road-based indicators of urban living. It is a relatively new data source that has mostly been used to map land-use classes [3], identify public properties [4], and construct urban transportation-network models [5].

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Problem Statement

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Problem Statement

Our contribution lies in synthesizing two freely available datasets of

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Problem Statement

Our contribution lies in synthesizing two freely available datasets of

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Problem Statement

Our contribution lies in synthesizing two freely available datasets of

Satellite imagery from Sentinel2 Road Information from Open Street Maps

and

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Problem Statement

Our contribution lies in synthesizing two freely available datasets of

Satellite imagery from Sentinel2 Road Information from Open Street Maps

and

to develop a series of standardized indicators for different aspects of urbanization, which can serve to compare various cities with one another and to track change happening in the cities over time

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Problem Statement

Our approach will support urban planners, government authorities, and citizens in answering questions such as the following: ➢ What is the spatial footprint of built-up areas in different cities? Which cities have undergone rapid spatial expansion of their built-up areas? ➢ How do cities differ in terms of the construction density of their urban settlements? Which cities have the most densely packed settlements? ➢ How are different urban settlements within a city changing over time? ➢ How does information on road networks enhance our understanding on the patterns of urbanization?

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Methodology

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Methodology

Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Built-up Change Detection (2016-2019)

2016 2017 2018 2019 Land-cover Predictions

We obtained Sentinel-2 data and applied a land-use classifier as an ongoing study [1]. Classifier Trained on: 3.5M pixels at 30m resolution Identified Land-cover classes: Water Body, Greenland, Barren Land, and Built-Up area The classifier produces a single classification for each year but takes images from the entire year into account to apply error correcting rules to handle seasonality. A robust accuracy of 97% has been reported for the classifier.

[1] HariOm Ahlawat. 2020. An open dataset for landuse classification in India for Sentinel-2. https://github.com/hariomahlawat/An-open-dataset-for-landuse-classification-in-India-for-Sentinel-2

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Built-up Change Detection (2016-2019)

2016 2017 2018 2019 Land-cover Predictions

Convert into Builtup/Non-Builtup Maps for each year

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Built-up Change Detection (2016-2019)

2016 2017 2018 2019 Land-cover Predictions

Apply Linear Regression to find constant and changing pixels

Convert into Builtup/Non-Builtup Maps for each year

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Built-up Change Detection (2016-2019)

2016 2017 2018 2019 Land-cover Predictions

Apply Linear Regression to find constant and changing pixels

Convert into Builtup/Non-Builtup Maps for each year

CBU/CNBU/Changing Map

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Built-up Change Detection (2016-2019)

2016 2017 2018 2019 Land-cover Predictions

Apply Linear Regression to find constant and changing pixels

Convert into Builtup/Non-Builtup Maps for each year

CBU/CNBU/Changing Map

Overall Accuracy: 93.90%

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Per-pixel Rural, Peri-urban, and Urban mapping

For each pixel, we count the percentage of builtup (BU) pixels in its Walking Distance Circle

If percentage >= 50% ----> Pixel is labeled URBAN If 25% <= percentage < 50% ----> Pixel is labeled PERI-URBAN If percentage <25% ----> Pixel is labeled RURAL

[1] Shlomo Angel, Alejandro M Blei, Daniel L Civco, and Jason Parent. 2012. Atlas of urban expansion. Lincoln Institute of Land Policy Cambridge, MA.

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Per-pixel Rural, Peri-urban, and Urban mapping

For each pixel, we count the percentage of builtup (BU) pixels in its Walking Distance Circle

If percentage >= 50% ----> Pixel is labeled URBAN If 25% <= percentage < 50% ----> Pixel is labeled PERI-URBAN If percentage <25% ----> Pixel is labeled RURAL

Target pixel

[1] Shlomo Angel, Alejandro M Blei, Daniel L Civco, and Jason Parent. 2012. Atlas of urban expansion. Lincoln Institute of Land Policy Cambridge, MA.

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Per-pixel Rural, Peri-urban, and Urban mapping

For each pixel, we count the percentage of builtup (BU) pixels in its Walking Distance Circle

If percentage >= 50% ----> Pixel is labeled URBAN If 25% <= percentage < 50% ----> Pixel is labeled PERI-URBAN If percentage <25% ----> Pixel is labeled RURAL

Target pixel

2016 2019

This defines the URBAN EXTENT of each city

[1] Shlomo Angel, Alejandro M Blei, Daniel L Civco, and Jason Parent. 2012. Atlas of urban expansion. Lincoln Institute of Land Policy Cambridge, MA.

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Selection of Urbanized Grids

Each city is divided into grids of 0.01° latitude and longitude in size. This grid size roughly denotes 1 Km2 of area.

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Selection of Urbanized Grids

Each city is divided into grids of 0.01° latitude and longitude in size. This grid size roughly denotes 1 Km2 of area. A grid with more than 50% of pixels labeled as either urban or peri-urban is termed as an Urbanized Grid

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Selection of Urbanized Grids

Each city is divided into grids of 0.01° latitude and longitude in size. This grid size roughly denotes 1 Km2 of area. A grid with more than 50% of pixels labeled as either urban or peri-urban is termed as an Urbanized Grid

2016 2019

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM)

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM) NOTE !! We select only those cities for which OSM data seems complete, based on not very active updates being performed now

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM) The OSM data is modeled as a graph and is used to compute the following road-based indicators-

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- #3-way Intersections

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- #4-way Intersections #3-way Intersections

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- #4-way Intersections #3-way Intersections

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- Total Road Length #4-way Intersections #3-way Intersections

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- Total Road Length Walkability Ratio #4-way Intersections #3-way Intersections

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Grid-level Road Network Analysis using OSM Data

For each of the urbanized grids, the road information associated with it is downloaded from the Open Street Maps (OSM). The OSM data is modeled as a graph and is used to compute the following road-based indicators- Total Road Length Walkability Ratio #4-way Intersections #3-way Intersections

Walkability Ratio = Beeline_distance / Shortest_path

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Categorization of Urbanized Grids

We cluster the urbanized grids based on 4 parameters- #3-way intersections, #4-way intersections, Walkability Ratio, Urban Footprint

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Categorization of Urbanized Grids

We cluster the urbanized grids based on 4 parameters- #3-way intersections, #4-way intersections, Walkability Ratio, Urban Footprint Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

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Categorization of Urbanized Grids

Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

Class 1 Sparse settlements with less road infrastructure

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Categorization of Urbanized Grids

Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

Class 1 Sparse settlements with less road infrastructure Class 2 Sparse settlements with better road infrastructure

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Categorization of Urbanized Grids

Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

Class 1 Sparse settlements with less road infrastructure Class 2 Sparse settlements with better road infrastructure Class 3 Moderately dense settlements with proportionate road infrastructure

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Categorization of Urbanized Grids

Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

Class 1 Sparse settlements with less road infrastructure Class 2 Sparse settlements with better road infrastructure Class 3 Moderately dense settlements with proportionate road infrastructure Class 4 Dense settlements with proportionate road infrastructure & more formally developed

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Categorization of Urbanized Grids

Using the Hierarchical Clustering method, we obtain 5 Classes of Urbanized Grids

Class 1 Sparse settlements with less road infrastructure Class 2 Sparse settlements with better road infrastructure Class 3 Moderately dense settlements with proportionate road infrastructure Class 4 Dense settlements with proportionate road infrastructure & more formally developed Class 5 Highly dense settlements with insufficient road infrastructure

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Sentinel-2 images Built-up change detection Selection of urbanized grids Grid-level road network analysis OSM data Categorization of Urbanized Grids Cross-sectional Indicators: 1. Urban Extent (UE) 2. Walkability Ratio 3. Road Length 4. #3-way Intersections 5. #4-way Intersections 6. Urbanized class density Temporal Change Indicators: 1. %Increase UE 2. Rural/Peri-urban/Urban Transition Matrix 3. %Increase in urbanized class density 4. Inter-class transition matrix Per-pixel Rural, Peri-urban, and urban mapping

Methodology

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Results

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What is the urban extent of different cities?

Urban Extent is the fraction of land in a district that has a reasonably high density of construction for it to be considered as supporting an urban or peri-urban settlement.

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What is the urban extent of different cities?

Urban Extent is the fraction of land in a district that has a reasonably high density of construction for it to be considered as supporting an urban or peri-urban settlement. Chennai, Kolkata, and Hyderabad have the greatest urban extent, followed by Mumbai, Delhi, Gurgaon, and Bangalore.

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How do cities differ in terms of the density of their urban settlements?

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How do cities differ in terms of the density of their urban settlements?

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How do cities differ in terms of the density of their urban settlements?

The aggregate density of C3, C4, and C5 grids indicate high density

  • f built-up infrastructure.
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How do cities differ in terms of the density of their urban settlements?

The aggregate density of C3, C4, and C5 grids indicate high density

  • f built-up infrastructure.

Hyderabad is highly dense, followed by Delhi, Chennai, Kolkata, Mumbai, Gurgaon, and Bangalore.

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How do cities differ in terms of the density of their urban settlements?

It is interesting to note that Hyderabad not only has a high urban extent, it also has a high density of settlements, indicating that the city has limited room for expansion. Chennai also has a high urban extent, but not a very high density in its settlements.

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Which cities have a large presence of densely packed areas that lack adequate road infrastructure?

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Which cities have a large presence of densely packed areas that lack adequate road infrastructure? The density of C5-grids is an indicator of areas that are densely packed and also lack an adequate road infrastructure.

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Which cities have a large presence of densely packed areas that lack adequate road infrastructure? The density of C5-grids is an indicator of areas that are densely packed and also lack an adequate road infrastructure. Delhi has a high density of these grids, and is closely followed by Mumbai and Hyderabad.

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Which cities have a large presence of densely packed areas that lack adequate road infrastructure? The density of C5-grids is an indicator of areas that are densely packed and also lack an adequate road infrastructure. Delhi has a high density of these grids, and is closely followed by Mumbai and Hyderabad. Even Gurgaon, despite being a newer city with heavy industrial development, has over 11% of its urbanized grids lacking adequate road infrastructure.

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What are the central hubs around which cities are organized?

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What are the central hubs around which cities are organized?

We try to answer this question based on a heatmap visualization of road-lengths.

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What are the central hubs around which cities are organized?

Delhi is highly polycentric having multiple urban hubs, followed by Mumbai and Hyderabad.

Delhi Hyderabad Mumbai

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What are the central hubs around which cities are organized?

Delhi is highly polycentric having multiple urban hubs, followed by Mumbai and Hyderabad.

Delhi Hyderabad Mumbai Chennai Kolkata

In comparison, Chennai and Kolkata seem to have developed in two distinct parts.

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What are the central hubs around which cities are organized?

Delhi is highly polycentric having multiple urban hubs, followed by Mumbai and Hyderabad.

Delhi Hyderabad Mumbai Chennai Kolkata Bangalore Gurgaon

In comparison, Chennai and Kolkata seem to have developed in two distinct parts. While Bangalore and Gurgaon have mostly grown around a center.

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Which cities have undergone rapid spatial expansion in built-up areas?

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Which cities have undergone rapid spatial expansion in built-up areas?

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Which cities have undergone rapid spatial expansion in built-up areas?

Bangalore and Delhi saw the largest amount of conversion of rural land into urban settlements, in terms of the absolute number of square kilometers converted.

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Which cities have undergone rapid spatial expansion in built-up areas?

Bangalore and Delhi saw the largest amount of conversion of rural land into urban settlements, in terms of the absolute number of square kilometers converted. Bangalore indeed has recently been ranked as the third fastest growing city in the world [1].

[1] Johnny Wood. 2018. The 10 fastest-growing cities in the world are all in India. https://www.weforum.org/agenda/2018/12/all-of-the-world-s-top-10-cities-with-the-fastest-growing-economies-will-be-in-india/

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How are different urban settlements within a city changing

  • ver time?
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How are different urban settlements within a city changing

  • ver time?
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How are different urban settlements within a city changing

  • ver time?

The cities like Bangalore, Gurgaon, and Chennai have a net increase in their C1-grids, showing that these grids indicate emerging settlements after the year 2016.

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How are different urban settlements within a city changing

  • ver time?

The cities like Bangalore, Gurgaon, and Chennai have a net increase in their C1-grids, showing that these grids indicate emerging settlements after the year 2016. In other cities like Mumbai, Hyderabad, and Kolkata, the increase in the density

  • f either C4 or C5 grids reveals an

infilling pattern of urbanization which is making them more congested over the years.

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Conclusion

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Conclusion

Our work goes beyond state of the art in having developed a standardized methodology that makes it possible to compare different cities with one another, track changes at fine spatial scales across the entire city, and derive a nuanced understanding of the nature of these changes.

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Conclusion

Our work goes beyond state of the art in having developed a standardized methodology that makes it possible to compare different cities with one another, track changes at fine spatial scales across the entire city, and derive a nuanced understanding of the nature of these changes. A limitation of using OSM data is that it may not be very complete or accurate for all cities, and although we took precautions in selecting only those cities for which the data seemed reliable, we may not be able to use OSM data for just about any city.

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Conclusion

Our work goes beyond state of the art in having developed a standardized methodology that makes it possible to compare different cities with one another, track changes at fine spatial scales across the entire city, and derive a nuanced understanding of the nature of these changes. A limitation of using OSM data is that it may not be very complete or accurate for all cities, and although we took precautions in selecting only those cities for which the data seemed reliable, we may not be able to use OSM data for just about any city. As part of future work, our methods can be easily extended using alternatives like Google Maps that have a paid API and are likely to be more complete.

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Thank You

Chahat Bansal chahat.bansal@cse.iitd.ac.in Indian Institute of Technology, Delhi