Bergas-Masso Elisa, Hamilton Douglas S, Myriokefalitakis Stelios, Rathod Sagar, Gonçalves Ageitos María, Pérez García-Pando Carlos
Barcelona Supercomputing Center, Barcelona, Spain.
Universitat Politècnica de Catalunya, Barcelona, Spain.
Nat Clim Chang. 2025;15(7):784-792. doi: 10.1038/s41558-025-02356-4. Epub 2025 Jun 13.
Rapid shifts in fire regimes affect the carbon cycle by releasing carbon and nutrients such as iron (Fe), potentially enhancing marine productivity and carbon export. Here we use fire emission projections and Earth system models to examine how climate-driven changes in fire emissions may alter soluble Fe (SFe) deposition and productivity. By century's end, climate change could increase Fe emissions from fires by 1.7-1.8 times beyond projections considering only direct human influences. Model projections show rising SFe deposition in Northern Hemisphere high latitudes under increasing socio-economic activity, potentially boosting the impact of SFe deposition on productivity in the Fe-limited North Atlantic by up to 20% annually (40% in summer), assuming stable macronutrient levels. However, declining macronutrient availability may shrink Fe-limited areas, where climate-driven fires could offset productivity losses by 7-8%. In the Southern Ocean, fossil fuel emissions primarily control SFe deposition, as reductions in anthropogenic fires counterbalance climate-driven increases.
火灾模式的快速转变通过释放碳和铁（Fe）等养分影响碳循环，这可能会提高海洋生产力和碳输出。在此，我们使用火灾排放预测和地球系统模型来研究气候驱动的火灾排放变化如何改变可溶性铁（SFe）沉降和生产力。到本世纪末，气候变化可能使火灾产生的铁排放量比仅考虑直接人类影响的预测增加1.7至1.8倍。模型预测表明，在社会经济活动增加的情况下，北半球高纬度地区的SFe沉降量会上升，假设常量营养素水平稳定，这可能会使SFe沉降对铁限制的北大西洋生产力的影响每年最多提高20%（夏季提高40%）。然而，常量营养素可用性的下降可能会缩小铁限制区域，在这些区域，气候驱动的火灾可抵消7-8%的生产力损失。在南大洋，化石燃料排放主要控制SFe沉降，因为人为火灾的减少抵消了气候驱动的增加。
