While there is agreement that global warming over the 21st century is likely to influence the biological pump, Earth system models (ESMs) display significant divergence in their projections of future new production. This paper quantifies and interprets the sensitivity of projected changes in new production in an idealized global ocean biogeochemistry model. The model includes two tracers that explicitly represent nutrient transport, light- and nutrient-limited nutrient uptake by the ecosystem (new production), and export via sinking organic particles. Globally, new production declines with warming due to reduced surface nutrient availability, as expected. However, the magnitude, seasonality, and underlying dynamics of the nutrient uptake are sensitive to the light and nutrient dependencies of uptake, which we summarize in terms of a single biological timescale that is a linear combination of the partial derivatives of production with respect to light and nutrients. Although the relationships are nonlinear, this biological timescale is correlated with several measures of biogeochemical function: shorter timescales are associated with greater global annual new production and higher nutrient utilization. Shorter timescales are also associated with greater declines in global new production in a warmer climate and greater sensitivity to changes in nutrients than light. Future work is needed to characterize more complex ocean biogeochemical models in terms of similar timescale generalities to examine their climate change implications.

中文翻译：

---

21世纪预计的海洋新生产变化对理想化生物地球化学模型结构的敏感性

尽管人们一致认为21世纪的全球变暖可能会影响生物泵，但地球系统模型（ESM）在其未来新产量的预测中显示出很大的分歧。本文在理想的全球海洋生物地球化学模型中量化并解释了新生产中预计变化的敏感性。该模型包括两个示踪剂，分别明确表示养分运输，生态系统对光和养分的养分吸收（新生产）以及通过下沉有机颗粒的出口。在全球范围内，新的生产随着变暖而下降，这是由于预期的表面养分供应减少所致。但是，养分吸收的幅度，季节性和基本动态对吸收的光和养分依赖性很敏感，我们根据单个生物时间尺度来总结，该时间尺度是相对于光和养分的生产偏导数的线性组合。尽管这些关系是非线性的，但该生物时间尺度与生物地球化学功能的几种度量值相关：较短的时间尺度与较高的全球年新产量和较高的养分利用率相关。较短的时间尺度还与在温暖的气候下全球新产量的更大下降以及对养分变化（比光）的敏感性更高有关。需要以相似的时间尺度概括性来表征更复杂的海洋生物地球化学模型，以研究其对气候变化的影响，今后需要开展工作。