Annemarie Schneider | University of Wisconsin-Madison (original) (raw)

Papers by Annemarie Schneider

Urbanization---both the shift in population to urban areas and the physical transformation of lan... more Urbanization---both the shift in population to urban areas and the physical transformation of land---has accelerated in recent decades in nearly all parts of the world. Urban growth is known to affect local environments through microclimatic changes, pollution, and loss of natural and agricultural lands, and has the potential to influence global circulation, biogeochemistry, and energy balance. To assess these impacts, rates and patterns of urban expansion and their relation to socioeconomic drivers must be determined. A combination of multiple sources of coarse resolution remotely sensed data and a Bayesian data fusion approach result in global maps of urban areas that show reasonable accuracy in terms of the size and location of cities, and are suitable for use in regional-global climate models. To understand changes in urban form locally, medium-resolution remote sensing data, pattern metrics, and local census data are combined to provide a suite of urban growth indicators that facilitate comparison of trends across cities from different regions and different levels of economic development. Chengdu, a rapidly developing city in Western China, provides an ideal case study to test these methods. Results show that the city has increased in area over 350% from 1978 to 2002, while expanding primarily along transportation routes with fragmentation in periurban areas. Comparison of growth metrics for 25 cities from 13 countries for the period 1990-2000 reveals four city types: low-growth cities characterized by modest rates of infilling-type expansion, high-growth cities with rapid, fragmented development, expansive-growth cities with extensive dispersion at low population densities, and frantic-growth cities such as Chengdu, that exhibit extraordinary rates of growth at high population densities. Although all 25 cities are expanding at the urban-rural boundary, cities outside of the U.S. do not show evidence of the large, dispersed spatial forms characteristic of American urban sprawl. Empirical analysis of the linkages between urban growth and population, household, and labor data shows a limited relationship between urban expansion and population change, a factor conventionally thought to play a role in land conversion. Local economic restructuring to industry and service-oriented activities shows some importance in urban growth and dispersion.

Population and Environment

Significant advances have been made to understand the interrelationship between humans and the en... more Significant advances have been made to understand the interrelationship between humans and the environment in recent years, yet research has not produced useful localized estimates that link population forecasts to environmental change. Coarse, static population estimates that have little information on projected growth or spatial variability mask substantial impacts of environmental change on especially vulnerable populations. We estimate that 20 million people in the United States will be affected by sea-level rise by 2030 in selected regions that represent a range of sociodemographic characteristics and corresponding risks of vulnerability. Our results show that the impact of sea-level rise extends beyond the directly impacted counties due to migration networks that link inland and coastal areas and their populations. Substantial rates of population growth and migration are serious considerations for developing mitigation, adaptation, and planning strategies, and for future research on the social, demographic, and political dimensions of climate change.

This paper describes research to obtain continental and global scale maps of urban land cover fro... more This paper describes research to obtain continental and global scale maps of urban land cover from remotely sensed imagery, specifically utilizing newly available one kilometer data from the MODIS sensor. Defining the extent of urban land is crucial, since knowledge of the size and spatial distribution of cities is important on a number of fronts, from resource management to economic development planning to regional and global climate modeling. The algorithm used for this work is a supervised decision tree classifier, and the technique of boosting is exploited to improve classification accuracy and to provide a means to correct major sources of error using available prior information. First results for North America indicate that the incorporation of. ancillary information successfully improves urban classification results, resolving confusion between the urban and barren classes that normally occurs when only MODIS data is used

Remote Sensing of Environment, 2010

Environment and Planning B-planning & Design, 2005

Remote Sensing of Environment, 2010

Geophysical Research Letters, 2004

Human activity, through changing land use and other activities, is the most fundamental source of... more Human activity, through changing land use and other activities, is the most fundamental source of environmental change on the Earth. Urbanization and the resultant ``urban heat islands'' provide a means for evaluating the effect of climate warming on vegetation phenology. Using data from the Moderate Resolution Imaging Spectroradiometer, we analyzed urban-rural differences in vegetation phenological transition dates and land surface temperatures for urban areas larger than 10 km2 in eastern North America. The results show that the effect of urban climates on vegetation phenology decays exponentially with distance from urban areas with substantial influence up to 10 km beyond the edge of urban land cover, and that the ecological ``footprint'' of urban climates is about 2.4 times that of urban land use in eastern North America. The net effect is an increase in the growing season by about 15 days in urban areas relative to adjacent unaffected rural areas.

Urban Studies, 2008

... 25 Vietnam Hanoi 2 311 500 3 007 829 257.0 348.1 ... Since the majority of urban expansion oc... more ... 25 Vietnam Hanoi 2 311 500 3 007 829 257.0 348.1 ... Since the majority of urban expansion occurs along the urban-to-rural transition zone, it was critical to have a means to compare this transition area across cities that may vary considerably in core city size. ...

Remote Sensing of Environment, 2002

International Journal of Remote Sensing, 2009

Eight groups from government and academia have created 10 global maps that offer a ca 2000 portra... more Eight groups from government and academia have created 10 global maps that offer a ca 2000 portrait of land in urban use. Our initial investigation found that their estimates of the total amount of urban land differ by as much as an order of magnitude (0.27–3.52 ×106 km2). Since it is not possible for these heterogeneous maps to all represent urban areas accurately, we undertake the first global accuracy assessment of these maps using a two-tiered approach that draws on a stratified random sample of 10 000 high-resolution Google Earth validation sites and 140 medium-resolution Landsat-based city maps. Employing a wide range of accuracy measures at different spatial scales, we conclude that the new MODIS 500 m resolution global urban map has the highest accuracy, followed by a thresholded version of the Global Impervious Surface Area map based on the Night-time Lights and LandScan datasets.

Geophysical Research Letters, 2004

Iop Conference Series: Earth and Environmental Science, 2009

ABSTRACT This article was submitted without an abstract, please refer to the full-text PDF file.

Identifying and anticipating the location, size and growth rate of urbanized areas is an importan... more Identifying and anticipating the location, size and growth rate of urbanized areas is an important component to understanding, adapting to, and mitigating many aspects of global change. The main objective of this research is to improve understanding of the methodological, scale and validation requirements for mapping urban land cover from coarse resolution remotely sensed MODIS one kilometer data. Defining the extent of urban land is crucial, since knowledge of the size and spatial distribution of cities is important for regional and global environmental modeling as well as resource management and economic development planning. This research relies on the use of a supervised decision tree classifier, a nonparametric algorithm that has been shown to be effective for classifying noisy and incomplete data sets: a technique called boosting improves classification accuracy and provides a means to correct major sources of error using available prior information from the DMSP-OLS radiance calibrated nighttime lights data set. Results for North America indicate that the incorporation of DMSP-OLS data successfully improves urban classification results. Traditional as well as new measures of accuracy assessment demonstrate the effectiveness of the methodology for creating accurate maps of cities over large areas

... Annemarie Schneidera, Karen C. Setob, and Curtis E. Woodcocka a Department of Geography ... A... more ... Annemarie Schneidera, Karen C. Setob, and Curtis E. Woodcocka a Department of Geography ... A reliable means to distinguish agriculture from urban change is use of seasonal ... A supervised decision tree classification algorithm (C4.5) was chosen, since this algorithm has been ...

Although only a small percentage of global land cover, urban areas significantly alter climate, b... more Although only a small percentage of global land cover, urban areas significantly alter climate, biogeochemistry, and hydrology at local, regional, and global scales. Despite the fact that three billion people live in cities, information related to global geographic patterns in urban extent and density is poor. Here we present results from efforts to map the global distribution of urban land use at 463 m spatial resolution using remotely sensed data from MODIS. Our approach uses a supervised decision tree classification algorithm that we process using region-specific parameters. The resulting map shows that urban areas occupy only 0.5-1.0 percent of the Earth's land area. Because resource and energy consumption is concentrated in urban areas, the geographic distribution and intensity of urban land use has important implications for models and related studies that require information related to role of humans in the global environment.

Geojournal, 2007

According to the UN, the number of urban dwellers is expected to increase from roughly 3.2 billio... more According to the UN, the number of urban dwellers is expected to increase from roughly 3.2 billion today to more than 4.9 billion by 2030. An accurate and regularly updated estimate of the extent and spatial distribution of urban land is an important first step in our search for realistic responses to the ecological and social consequences of what promises to be the most rapid urbanization in world history. By employing circa-2000 satellite remote sensing imagery, geographic information systems, and census data, six groups from government and academia in both the EU and the US have created global maps that can be used to describe urban land. We compare these maps from global to sub-national scales, for the first time applying Discrete Global Grids to the problem of global-scale map comparison. Although most of these maps share common data inputs, they differ by as much as an order of magnitude in their estimates of the total areal extent of the Earth’s urban land (from 0.27 to 3.52 million km2). A sub-national analysis of the spatial distribution of urban land reveals that inter-map correlations are highest in North America ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.90), intermediate in Europe, South and Central America, and Sub-Saharan Africa ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.78), and lowest in Asia ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.63). Across most regions, our analysis uncovers a degree of variance that is high enough to call into question the consistency of each group’s approach to urban land, pointing to the need for both a common urban taxonomy and a global urban assessment effort.

Urbanization---both the shift in population to urban areas and the physical transformation of lan... more Urbanization---both the shift in population to urban areas and the physical transformation of land---has accelerated in recent decades in nearly all parts of the world. Urban growth is known to affect local environments through microclimatic changes, pollution, and loss of natural and agricultural lands, and has the potential to influence global circulation, biogeochemistry, and energy balance. To assess these impacts, rates and patterns of urban expansion and their relation to socioeconomic drivers must be determined. A combination of multiple sources of coarse resolution remotely sensed data and a Bayesian data fusion approach result in global maps of urban areas that show reasonable accuracy in terms of the size and location of cities, and are suitable for use in regional-global climate models. To understand changes in urban form locally, medium-resolution remote sensing data, pattern metrics, and local census data are combined to provide a suite of urban growth indicators that facilitate comparison of trends across cities from different regions and different levels of economic development. Chengdu, a rapidly developing city in Western China, provides an ideal case study to test these methods. Results show that the city has increased in area over 350% from 1978 to 2002, while expanding primarily along transportation routes with fragmentation in periurban areas. Comparison of growth metrics for 25 cities from 13 countries for the period 1990-2000 reveals four city types: low-growth cities characterized by modest rates of infilling-type expansion, high-growth cities with rapid, fragmented development, expansive-growth cities with extensive dispersion at low population densities, and frantic-growth cities such as Chengdu, that exhibit extraordinary rates of growth at high population densities. Although all 25 cities are expanding at the urban-rural boundary, cities outside of the U.S. do not show evidence of the large, dispersed spatial forms characteristic of American urban sprawl. Empirical analysis of the linkages between urban growth and population, household, and labor data shows a limited relationship between urban expansion and population change, a factor conventionally thought to play a role in land conversion. Local economic restructuring to industry and service-oriented activities shows some importance in urban growth and dispersion.

Population and Environment

Significant advances have been made to understand the interrelationship between humans and the en... more Significant advances have been made to understand the interrelationship between humans and the environment in recent years, yet research has not produced useful localized estimates that link population forecasts to environmental change. Coarse, static population estimates that have little information on projected growth or spatial variability mask substantial impacts of environmental change on especially vulnerable populations. We estimate that 20 million people in the United States will be affected by sea-level rise by 2030 in selected regions that represent a range of sociodemographic characteristics and corresponding risks of vulnerability. Our results show that the impact of sea-level rise extends beyond the directly impacted counties due to migration networks that link inland and coastal areas and their populations. Substantial rates of population growth and migration are serious considerations for developing mitigation, adaptation, and planning strategies, and for future research on the social, demographic, and political dimensions of climate change.

This paper describes research to obtain continental and global scale maps of urban land cover fro... more This paper describes research to obtain continental and global scale maps of urban land cover from remotely sensed imagery, specifically utilizing newly available one kilometer data from the MODIS sensor. Defining the extent of urban land is crucial, since knowledge of the size and spatial distribution of cities is important on a number of fronts, from resource management to economic development planning to regional and global climate modeling. The algorithm used for this work is a supervised decision tree classifier, and the technique of boosting is exploited to improve classification accuracy and to provide a means to correct major sources of error using available prior information. First results for North America indicate that the incorporation of. ancillary information successfully improves urban classification results, resolving confusion between the urban and barren classes that normally occurs when only MODIS data is used

Remote Sensing of Environment, 2010

Environment and Planning B-planning & Design, 2005

Remote Sensing of Environment, 2010

Geophysical Research Letters, 2004

Human activity, through changing land use and other activities, is the most fundamental source of... more Human activity, through changing land use and other activities, is the most fundamental source of environmental change on the Earth. Urbanization and the resultant ``urban heat islands'' provide a means for evaluating the effect of climate warming on vegetation phenology. Using data from the Moderate Resolution Imaging Spectroradiometer, we analyzed urban-rural differences in vegetation phenological transition dates and land surface temperatures for urban areas larger than 10 km2 in eastern North America. The results show that the effect of urban climates on vegetation phenology decays exponentially with distance from urban areas with substantial influence up to 10 km beyond the edge of urban land cover, and that the ecological ``footprint'' of urban climates is about 2.4 times that of urban land use in eastern North America. The net effect is an increase in the growing season by about 15 days in urban areas relative to adjacent unaffected rural areas.

Urban Studies, 2008

... 25 Vietnam Hanoi 2 311 500 3 007 829 257.0 348.1 ... Since the majority of urban expansion oc... more ... 25 Vietnam Hanoi 2 311 500 3 007 829 257.0 348.1 ... Since the majority of urban expansion occurs along the urban-to-rural transition zone, it was critical to have a means to compare this transition area across cities that may vary considerably in core city size. ...

Remote Sensing of Environment, 2002

International Journal of Remote Sensing, 2009

Eight groups from government and academia have created 10 global maps that offer a ca 2000 portra... more Eight groups from government and academia have created 10 global maps that offer a ca 2000 portrait of land in urban use. Our initial investigation found that their estimates of the total amount of urban land differ by as much as an order of magnitude (0.27–3.52 ×106 km2). Since it is not possible for these heterogeneous maps to all represent urban areas accurately, we undertake the first global accuracy assessment of these maps using a two-tiered approach that draws on a stratified random sample of 10 000 high-resolution Google Earth validation sites and 140 medium-resolution Landsat-based city maps. Employing a wide range of accuracy measures at different spatial scales, we conclude that the new MODIS 500 m resolution global urban map has the highest accuracy, followed by a thresholded version of the Global Impervious Surface Area map based on the Night-time Lights and LandScan datasets.

Geophysical Research Letters, 2004

Iop Conference Series: Earth and Environmental Science, 2009

ABSTRACT This article was submitted without an abstract, please refer to the full-text PDF file.

Identifying and anticipating the location, size and growth rate of urbanized areas is an importan... more Identifying and anticipating the location, size and growth rate of urbanized areas is an important component to understanding, adapting to, and mitigating many aspects of global change. The main objective of this research is to improve understanding of the methodological, scale and validation requirements for mapping urban land cover from coarse resolution remotely sensed MODIS one kilometer data. Defining the extent of urban land is crucial, since knowledge of the size and spatial distribution of cities is important for regional and global environmental modeling as well as resource management and economic development planning. This research relies on the use of a supervised decision tree classifier, a nonparametric algorithm that has been shown to be effective for classifying noisy and incomplete data sets: a technique called boosting improves classification accuracy and provides a means to correct major sources of error using available prior information from the DMSP-OLS radiance calibrated nighttime lights data set. Results for North America indicate that the incorporation of DMSP-OLS data successfully improves urban classification results. Traditional as well as new measures of accuracy assessment demonstrate the effectiveness of the methodology for creating accurate maps of cities over large areas

... Annemarie Schneidera, Karen C. Setob, and Curtis E. Woodcocka a Department of Geography ... A... more ... Annemarie Schneidera, Karen C. Setob, and Curtis E. Woodcocka a Department of Geography ... A reliable means to distinguish agriculture from urban change is use of seasonal ... A supervised decision tree classification algorithm (C4.5) was chosen, since this algorithm has been ...

Although only a small percentage of global land cover, urban areas significantly alter climate, b... more Although only a small percentage of global land cover, urban areas significantly alter climate, biogeochemistry, and hydrology at local, regional, and global scales. Despite the fact that three billion people live in cities, information related to global geographic patterns in urban extent and density is poor. Here we present results from efforts to map the global distribution of urban land use at 463 m spatial resolution using remotely sensed data from MODIS. Our approach uses a supervised decision tree classification algorithm that we process using region-specific parameters. The resulting map shows that urban areas occupy only 0.5-1.0 percent of the Earth's land area. Because resource and energy consumption is concentrated in urban areas, the geographic distribution and intensity of urban land use has important implications for models and related studies that require information related to role of humans in the global environment.

Geojournal, 2007

According to the UN, the number of urban dwellers is expected to increase from roughly 3.2 billio... more According to the UN, the number of urban dwellers is expected to increase from roughly 3.2 billion today to more than 4.9 billion by 2030. An accurate and regularly updated estimate of the extent and spatial distribution of urban land is an important first step in our search for realistic responses to the ecological and social consequences of what promises to be the most rapid urbanization in world history. By employing circa-2000 satellite remote sensing imagery, geographic information systems, and census data, six groups from government and academia in both the EU and the US have created global maps that can be used to describe urban land. We compare these maps from global to sub-national scales, for the first time applying Discrete Global Grids to the problem of global-scale map comparison. Although most of these maps share common data inputs, they differ by as much as an order of magnitude in their estimates of the total areal extent of the Earth’s urban land (from 0.27 to 3.52 million km2). A sub-national analysis of the spatial distribution of urban land reveals that inter-map correlations are highest in North America ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.90), intermediate in Europe, South and Central America, and Sub-Saharan Africa ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.78), and lowest in Asia ( $ \ifmmode\expandafter\bar\else\expandafter\=\fi{r} $ = 0.63). Across most regions, our analysis uncovers a degree of variance that is high enough to call into question the consistency of each group’s approach to urban land, pointing to the need for both a common urban taxonomy and a global urban assessment effort.