Climate change involves a direct response of the climate system to forcing which is amplified or damped by feedbacks operating in the climate system. Carbon-cycle feedbacks alter the land and ocean carbon inventories and so act to reduce or enhance the increase in atmospheric CO₂ from carbon emissions. The prevailing framework for carbon-cycle feedbacks connect changes in land and ocean carbon inventories with a linear sum of dependencies on atmospheric CO₂ and surface temperature. Carbon-cycle responses and feedbacks provide competing contributions: the dominant effect is that increasing atmospheric CO₂ acts to enhance the land and ocean carbon stores, so providing a negative response and feedback to the original increase in atmospheric CO₂, while rising surface temperature acts to reduce the land and ocean carbon stores, so providing a weaker positive feedback for atmospheric CO₂. The carbon response and feedback of the land and ocean system may be expressed in terms of a combined carbon response and feedback parameter, λ_carbon in units of W m^− 2K^− 1, and is linearly related to the physical climate feedback parameter, λ_climate, revealing how carbon and climate responses and feedbacks are inter-connected. The magnitude and uncertainties in the carbon-cycle response and feedback parameter are comparable with the magnitude and uncertainties in the climate feedback parameter from clouds. Further mechanistic insight needs to be gained into how the carbon-cycle feedbacks are controlled for the land and ocean, particularly to separate often competing effects from changes in atmospheric CO₂ and climate forcing.

气候变化涉及气候系统对强迫的直接反应，该反应通过气候系统中运行的反馈而放大​​或减弱。碳循环反馈改变陆地和海洋碳库存，从而减少或增加碳排放导致的大气CO ₂的增加。碳循环反馈的主流框架将陆地和海洋碳库存的变化与大气CO ₂和地表温度的依赖关系的线性总和联系起来。碳循环响应和反馈提供了相互竞争的贡献：主要影响是大气 CO _{2 的增加会增强陆地和海洋的碳储存，因此对大气 CO 2}的原始增加提供了负响应和反馈，而表面温度的上升则起到了作用减少陆地和海洋碳储存，从而为大气CO ₂提供较弱的正反馈。陆地和海洋系统的碳响应和反馈可以用组合的碳响应和反馈参数λ_碳来表示，单位为 W m ^{− 2} K ^{− 1}，并且与物理气候反馈参数λ线性相关_气候，揭示碳与气候响应和反馈如何相互关联。碳循环响应和反馈参数的幅度和不确定性与云气候反馈参数的幅度和不确定性相当。需要进一步了解如何控制陆地和海洋的碳循环反馈，特别是要将经常相互竞争的影响与大气CO ₂和气候强迫的变化分开。