21世紀までに南アフリカの砂漠の砂丘システムの再動員
David S G Thomas1, Melanie Knight, Giles F S Wiggs
1School of Geography and Environment, Oxford University Centre for the Environment, University of Oxford, South Parks Road, Oxford OX1 3QY, UK. david.thomas@ouce.ox.ac.uk
Nature
|July 1, 2005
まとめ
地球温暖化は,2099年までにアフリカ全土で砂漠の砂丘の活動を大幅に増加させるだろう. 気候変動は砂丘の浸食性や侵食性に影響を及ぼし,砂丘の広範な再活性化と生態系と人間のシステムの潜在的な破壊につながります.
科学分野:
- 環境科学 環境科学
- 気候科学 気候科学
- ジオモルフォロジー ジオモルフォロジー
背景:
- 砂漠の砂丘は地球の5%とアフリカの30%をカバーしていますが,気候変動の影響は十分に理解されていません.
- サヘル地域と南アフリカにおける不活性な砂丘のシステムは,重要な牧牧と農業活動をサポートしています.
- 砂丘の動態は,表面浸食性 (植生,水分) と大気浸食性 (風力) の相互作用に依存しています.
研究 の 目的:
- 21世紀の地球温暖化の下で,カラハリの砂丘地帯の潜在的な将来の活動を評価する.
- 気候変動が砂丘のダイナミクスと再活性化にどのように影響するかを調査する.
- 異なる排出シナリオで砂丘の活動を予測する.
主な方法:
- 3つのグローバルな気候モデルからのシミュレーションを利用した.
- 気候モデルのデータを組み込むために確立された砂丘の移動性インデックスを修正し,改善しました.
- 侵食性および侵食性の予測された変化に基づいて,月間砂丘の活動を分析した.
主要な成果:
- 2039年までに,シミュレートされた砂丘活動が大幅に強化され,南部カラハリの砂丘地帯に広がる.
- 2069年までに東部と北部の砂丘地帯での活動強化が予測されています.
- 2099年までに南アフリカ全域 (南アフリカからアンゴラ,ザンビアまで) で,排出シナリオに関係なく,高度にダイナミックな砂丘地帯を示す.
結論:
- 21世紀の気候変動は,砂漠の砂丘システムの重要な再活性化を引き起こす可能性が高い.
- 砂丘の活動の増加は,安定した砂丘環境に依存する既存の牧草と農業システムにリスクをもたらします.
- 将来の気候変動は,潜在的な砂丘システムの変革を理解し管理するための積極的な措置を必要とします.
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