海冰盐水的冷诱导的酸性化
Lukáš Veselý1, Radim Štůsek1, Ondřej Mikula2
1Masaryk University, Faculty of Science, Department of Chemistry, Czech Republic.
The Science of the total environment
|June 26, 2024
概括
海冰酸度在结时显著增加,特别是在盐度较低的水域,影响极地化学. 这种酸度的增加与矿物质结晶和冷却过程中缓冲能力的损失有关.
科学领域:
- * * 冰层的化学结构
- * 环境化学 环境化学
- * 地质化学 * 地质化学
背景情况:
- *海冰和雪的酸度对于冰层化学是至关重要的.
- * 光化学反应,比如在极地释放,是依赖pH值的 (低于6.5).
研究的目的:
- * 为了研究海冰盐水中的微观酸度.
- * 了解海水盐度,结和酸度之间的关系.
- * 评估对极地化学过程的影响.
主要方法:
- * 现场酸指标用于测量人造海水中的微观酸度.
- * 对各种盐度 (0.35-70 PPT) 和初始pH值 (6-9) 进行测量.
- *对主要海水盐 (NaCl,Na2SO4,CaCO3) 进行了类似的测量.
主要成果:
- * 酸度 (哈梅特酸度函数,H2-) 在结在-15°C后,在进一步冷却到-50°C后,海水显著增加.
- * 在冷却和变暖周期之间没有观察到显著的歇斯底里.
- *较低盐度的海水 (≤3.5 PPT) 在-15°C时达到pH<6.5,而更高盐度的冰需要-30°C.
结论:
- * 在冷过程中矿物质结晶会降低缓冲能力,导致酸度增加.
- *这些发现突出了海冰中酸性条件的临界温度和盐度值.
- *结果对理解极地化学和解释现场测量有重大影响.
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