世界の人口の安定化は,今世紀にはありそうにない.
Patrick Gerland1, Adrian E Raftery2, Hana Sevčíková3
1Population Division, Department of Economic and Social Affairs, United Nations, New York, NY 10017, USA. gerland@un.org raftery@u.washington.edu.
まとめ
世界の人口増加が今世紀中に止まる可能性は低いが,予測では2100年までに90億~1230億人に増加するとしている. 生育率によって引き起こされるこの人口動態の変化は,アフリカに大きく影響し,世界の依存関係に変化をもたらすだろう.
科学分野:
- デモグラフィー デモグラフィー 人口統計
- 人口研究 人口研究
- グローバル・ヘルス グローバル・ヘルス
背景:
- 以前の人口予測は,世界の人口増加の安定化または減少を示唆していた.
- 国連 (UN) は歴史的に,さまざまな方法論を用いた人口推定を提供してきました.
研究 の 目的:
- ベイジアン確率的方法論を用いて,国連の最新の人口予測を分析する.
- 21世紀を通して世界人口の増加が続く可能性を再評価する.
主な方法:
- 人口予測分析のためにベイジアン確率論の方法論を利用した.
- 予測のための2012年まで利用可能な統合されたデータ.
- 伝統的な国連の高低変数予測と結果を比較した.
主要な成果:
- 世界の人口は,以前のいくつかの文献に反して,この世紀で増加を止める可能性は低い.
- 2100年までに世界の人口が96~123億人に達する確率は80%である.
- 人口増加はアフリカに集中すると予測されており,生育率と生育率減少のペースの低下の影響を受けます.
- 労働年齢と高齢者人口の比率の大幅な減少は,すべての国で予想されています.
結論:
- 世界の人口は2100年まで大幅に増加し続けると予測されています.
- アフリカは,将来の人口増加の主な原動力になると予想されています.
- 人口の変化は,世界的に高齢化人口を支援する上で課題をもたらすだろう.
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