温室气体减排可以减少海冰的消失,增加北极熊的持久性
Steven C Amstrup1, Eric T Deweaver, David C Douglas
1US Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, Alaska 99508, USA. samstrup@pbears.org
Nature
|December 18, 2010
概括
温室气体减排可以保护北极熊的海冰息地,使其种群持续存在. 这与早期预测的大幅下降形成鲜明对比,强调了气候行动对北极生态系统的好处.
科学领域:
- 气候科学 气候科学
- 北极生态学 北极生态学
- 保护生物学 保护生物学
背景情况:
- 之前的预测表明,到本世纪中叶,北极熊 (Ursus maritimus) 种群的数量将大幅下降,原因是海冰的息地在正常排放下丧失.
- 一个关键的问题是,海冰的减少是否与温度上升成比例,或者是否存在一个临界点,超出这一点,缓解努力将无效.
研究的目的:
- 调查温室气体减排对北极熊海冰息地保留的影响.
- 为了确定海冰损失是否遵循线性温度依赖关系或关键临界点.
- 评估不同气候场景下北极熊存在的可能性.
主要方法:
- 利用一般循环模型在各种温室气体排放场景下模拟海冰息地变化.
- 采用贝叶斯网络模型来分析息地保留和北极熊种群持续存在之间的关系.
- 研究了海冰热力学和白度反对潜在的临界点的影响.
主要成果:
- 当温室气体的增加得到缓解时,海冰息地被保留了更多,这与之前的可怕预测相反.
- 在全球平均地表空气温度和海冰息地之间发现了线性关系,驳斥了海冰转折点的存在.
- 贝叶斯网络的结果表明,北极熊的数量和分布可以在整个世纪保持在缓解努力下.
结论:
- 温室气体减排通过保护重要的海冰息地,为北极熊提供了显著的保护效益.
- 观察到的夏季快速冰损失归因于薄化冰的波动性增加,而不是临界点崩.
- 北极熊是北极海洋生态系统的关键哨兵,通过气候行动保护它们有利于更广泛的北极和全球环境.
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