2024-08-26-世界银行-外向型和向上型建筑_全球建筑存量的三维分析（英）_50页_19mb

Report Summary

1 Introduction

The study presents a new, high-resolution dataset (WSF3Dv2) analyzing the global building stock in 3D, using detailed area, height and volume measurements. This data aims to address previous limitations in low data resolution and coverage of developing economies. The research investigates the relationship between economic development, construction patterns (outward and upward), and their implications for sustainability and future construction needs.

2 Key Findings

2.1 Economic Development and Construction Patterns

• Global building volume per capita increases convexly with income, with this relationship strongest in upper-middle-income economies.
• Economic development accounts for ~62% of international volume differences, suggesting significant roles for other factors like land regulations.

2.2 Global Construction Needs

• Between 2012/2019 and 2050 urbanization, low-middle/low-income economies keep experiencing fast population growth, increasing their construction gaps dramatically.
• Africa's construction gaps increase 5.5x by 2050, while Asia and Latin America surpass Africa in total construction needs by 2050.

2.3 3D Construction Preferences and Impacts

• Vertical expansion (upward construction) accounts for ~65% of global volume differences, primarily driven by low-rise buildings (90%).
• Urbanization tends to reduce space consumption, while rural areas and small towns disproportionately influence volume differences.

2.4 3D Construction Specializations

• Regional/ national differences in 3D development specialization were observed:
  • Asia is overall the most pro-heights.
  • Latin America is predominantly pro-area.
  • Africa is largely pro-area and pro-low-rises.
• Land-use regulations (building heights, urban containment policies) appear crucial in driving these specializations.

3 Recommendation and Policy Implications

• Construction Needs: There are substantial environmental implications to meeting construction needs, especially in Asia and Africa by 2050. Rapid urbanization in Africa demands proportional policy focus regarding spatial planning and building density.
• Land Regulations: Since land-use regulations account for significant differences in construction patterns, their role in making cities more efficient (vertical expansion) versus promoting sprawl (horizontal expansion) requires better policy implementation.

4 Methodology

• An enhanced dataset combining high-resolution remote sensing and industry-specific data (Emporis), achieving 12m spatial resolution globally.
• Residualization techniques used to classify countries/ regions based on upward vs outward construction preferences conditional on income level, qualitatively improving settlement analysis at national and urban scales.

5 Limitations

• While covering most of the world's building stock, the data patchily documents building characteristics below 50m, possibly underestimating small structures.
• GDP-based income proxies may not fully capture localized income variations, especially in transitioning or informal economies.