Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways
Population change is a main driver behind global environmental change, including urban land expansion. In future scenario modeling, assumptions regarding how populations will change locally, despite identical global constraints of Shared Socioeconomic Pathways (SSPs), can have dramatic effects on su...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2024-01-01
|
| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/ad2eec |
| _version_ | 1797261662684708864 |
|---|---|
| author | Ryan A McManamay Alen Raad Chris R Vernon Travis Thurber Jing Gao Stephen Powers Brian O’Neill |
| author_facet | Ryan A McManamay Alen Raad Chris R Vernon Travis Thurber Jing Gao Stephen Powers Brian O’Neill |
| author_sort | Ryan A McManamay |
| collection | DOAJ |
| description | Population change is a main driver behind global environmental change, including urban land expansion. In future scenario modeling, assumptions regarding how populations will change locally, despite identical global constraints of Shared Socioeconomic Pathways (SSPs), can have dramatic effects on subsequent regional urbanization. Using a spatial modeling experiment at high resolution (1 km), this study compared how two alternative US population projections, varying in the spatially explicit nature of demographic patterns and migration, affect urban land dynamics simulated by the Spatially Explicit, Long-term, Empirical City development (SELECT) model for SSP2, SSP3, and SSP5. The population projections included: (1) newer downscaled state-specific population (SP) projections inclusive of updated international and domestic migration estimates, and (2) prevailing downscaled national-level projections (NP) agnostic to localized demographic processes. Our work shows that alternative population inputs, even those under the same SSP, can lead to dramatic and complex differences in urban land outcomes. Under the SP projection, urbanization displays more of an extensification pattern compared to the NP projection. This suggests that recent demographic information supports more extreme urban extensification and land pressures on existing rural areas in the US than previously anticipated. Urban land outcomes to population inputs were spatially variable where areas in close spatial proximity showed divergent patterns, reflective of the spatially complex urbanization processes that can be accommodated in SELECT. Although different population projections and assumptions led to divergent outcomes, urban land development is not a linear product of population change but the result of complex relationships between population, dynamic urbanization processes, stages of urban development maturity, and feedback mechanisms. These findings highlight the importance of accounting for spatial variations in the population projections, but also urbanization process to accurately project long-term urban land patterns. |
| first_indexed | 2024-04-24T23:44:47Z |
| format | Article |
| id | doaj.art-ad651d0986f545a68f35f20e8e228ba0 |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-04-24T23:44:47Z |
| publishDate | 2024-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-ad651d0986f545a68f35f20e8e228ba02024-03-15T08:38:05ZengIOP PublishingEnvironmental Research Letters1748-93262024-01-0119404402510.1088/1748-9326/ad2eecDivergent urban land trajectories under alternative population projections within the Shared Socioeconomic PathwaysRyan A McManamay0https://orcid.org/0000-0002-5551-3140Alen Raad1Chris R Vernon2https://orcid.org/0000-0002-3406-6214Travis Thurber3https://orcid.org/0000-0002-4370-9971Jing Gao4https://orcid.org/0000-0003-1778-8909Stephen Powers5Brian O’Neill6Department of Environmental Science, Baylor University , Waco, TX, United States of AmericaDepartment of Environmental Science, Baylor University , Waco, TX, United States of America; Department of Biology, Baylor University , Waco, TX, United States of AmericaPacific Northwest National Laboratory , Richland, WA, United States of AmericaPacific Northwest National Laboratory , Richland, WA, United States of AmericaDepartment of Geography and Spatial Science, University of Delaware , Newark, DE, United States of AmericaDepartment of Biology, Baylor University , Waco, TX, United States of AmericaPacific Northwest National Laboratory , Richland, WA, United States of AmericaPopulation change is a main driver behind global environmental change, including urban land expansion. In future scenario modeling, assumptions regarding how populations will change locally, despite identical global constraints of Shared Socioeconomic Pathways (SSPs), can have dramatic effects on subsequent regional urbanization. Using a spatial modeling experiment at high resolution (1 km), this study compared how two alternative US population projections, varying in the spatially explicit nature of demographic patterns and migration, affect urban land dynamics simulated by the Spatially Explicit, Long-term, Empirical City development (SELECT) model for SSP2, SSP3, and SSP5. The population projections included: (1) newer downscaled state-specific population (SP) projections inclusive of updated international and domestic migration estimates, and (2) prevailing downscaled national-level projections (NP) agnostic to localized demographic processes. Our work shows that alternative population inputs, even those under the same SSP, can lead to dramatic and complex differences in urban land outcomes. Under the SP projection, urbanization displays more of an extensification pattern compared to the NP projection. This suggests that recent demographic information supports more extreme urban extensification and land pressures on existing rural areas in the US than previously anticipated. Urban land outcomes to population inputs were spatially variable where areas in close spatial proximity showed divergent patterns, reflective of the spatially complex urbanization processes that can be accommodated in SELECT. Although different population projections and assumptions led to divergent outcomes, urban land development is not a linear product of population change but the result of complex relationships between population, dynamic urbanization processes, stages of urban development maturity, and feedback mechanisms. These findings highlight the importance of accounting for spatial variations in the population projections, but also urbanization process to accurately project long-term urban land patterns.https://doi.org/10.1088/1748-9326/ad2eecurbanizationscenariosland use and land cover changerural |
| spellingShingle | Ryan A McManamay Alen Raad Chris R Vernon Travis Thurber Jing Gao Stephen Powers Brian O’Neill Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways Environmental Research Letters urbanization scenarios land use and land cover change rural |
| title | Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways |
| title_full | Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways |
| title_fullStr | Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways |
| title_full_unstemmed | Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways |
| title_short | Divergent urban land trajectories under alternative population projections within the Shared Socioeconomic Pathways |
| title_sort | divergent urban land trajectories under alternative population projections within the shared socioeconomic pathways |
| topic | urbanization scenarios land use and land cover change rural |
| url | https://doi.org/10.1088/1748-9326/ad2eec |
| work_keys_str_mv | AT ryanamcmanamay divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT alenraad divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT chrisrvernon divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT travisthurber divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT jinggao divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT stephenpowers divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways AT brianoneill divergenturbanlandtrajectoriesunderalternativepopulationprojectionswithinthesharedsocioeconomicpathways |