浴度对长期碳循环和CCD的影响
Matthew Bogumil1, Tushar Mittal2, Carolina Lithgow-Bertelloni1
1Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095-1567.
概括
海洋底形状对地球的碳循环产生重大影响,影响海洋化学和碳酸盐补偿深度. 了解浴度变化对于准确的碳储存模型至关重要.
科学领域:
- 地质化学 地质化学
- 古海洋学是古海洋学.
- 地球系统科学 地球系统科学
背景情况:
- 海洋底的形状 (浴度) 和沉积物是地球上最大的碳汇.
- 浴度学影响沉积物积累/侵蚀和海洋化学.
- 之前的研究缺乏系统量化对浴度的长期碳循环影响.
研究的目的:
- 量化全球和盆地规模的浴度变化如何影响长期碳循环.
- 重建中生时代的浴度,并对其对海洋化学的影响进行建模.
- 评估浴度学在解释古海洋学变化的作用.
主要方法:
- 在过去的8000万年里重建了浴度.
- 利用地球系统模型LOSCAR模拟稳定状态海洋化学.
- 进行合成测试,分析浴度对海洋性,酸盐和和CCD的影响.
主要成果:
- 海洋的度,酸盐和状态和碳酸盐补偿深度 (CCD) 强烈依赖浅水度 (<600 m) 和深海区域 (>1,000 m).
- 仅仅浴度变化就预测了500米的CCD变化,解释了33-50%的观测到的古基记录.
- 忽视浴度会导致错误地将碳循环变化归因于其他因素.
结论:
- 浴度进化是长期碳循环的关键,经常被忽视的驱动因素.
- 准确的浴度重建对于可靠的地球系统模型和古气候研究至关重要.
- 早期古世时代的最新水位测量表明,气候变化的趋势是逆转的,与代理数据保持一致.
相关概念视频
01:14The Carbon Cycle
37.3K
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
37.3K
01:18Respiratory Regulation of Acid-Base Balance
375
Respiratory compensation is a vital physiological process that stabilizes blood plasma pH by regulating the partial pressure of carbon dioxide (PCO2), a key determinant of pH levels. Most carbon dioxide in the blood dissolves and converts into carbonic acid (H2CO3). It dissociates into hydrogen ions (H+) and bicarbonate ions (HCO3⁻). There is also an inverse relationship between PCO2 and pH.
When carbon dioxide levels increase in the blood, more H+ and HCO3⁻ are...
When carbon dioxide levels increase in the blood, more H+ and HCO3⁻ are...
375
01:28Compensation Mechanisms
276
The human body employs intricate mechanisms to counteract changes in blood pH, preventing conditions like acidosis (pH < 7.35) and alkalosis (pH > 7.45). These compensatory responses aim to restore normal arterial blood pH by engaging respiratory or renal systems, depending on the source of the imbalance.
Respiratory Compensation
This mechanism addresses metabolic-induced pH imbalances by adjusting breathing rates. Respiratory compensation begins within minutes of detecting a pH...
Respiratory Compensation
This mechanism addresses metabolic-induced pH imbalances by adjusting breathing rates. Respiratory compensation begins within minutes of detecting a pH...
276
01:22Bicarbonate-Carbonic Acid Buffer
1.3K
The carbonic acid-bicarbonate buffer system is critical for maintaining the body's pH balance. It operates on the equilibrium:
1.3K
01:50Global Climate Change
24.3K
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
24.3K
01:31Chemical Factors Affecting Respiration Centers
1.1K
Chemical factors such as changing CO2, O2, and H+ levels in arterial blood play a critical role in influencing respiration depth and rates. These variations are detected by chemoreceptors—specialized sensors located in two primary body areas. Central chemoreceptors are found throughout the brain stem, including the ventrolateral medulla, while peripheral chemoreceptors are located in the aortic arch and carotid arteries.
CO2 has a potent influence on respiration and is strictly regulated....
CO2 has a potent influence on respiration and is strictly regulated....
1.1K