Collaborative Research: Uncertainty in Predictions of 21st Century Ocean Biogeochemical Change

由于人为气候变化，海洋的生物地球化学正在发生大规模的变化。最近的研究表明，这些变化正在区域尺度上显著发生，但由于模式的不确定性，很难限制人为影响和自然影响之间的差异。在未来研究气候变化及其对海洋生物地球化学的影响时，至关重要的是能够区分这些影响；因此，识别和量化地球系统模式（esm）中的不确定性至关重要。研究人员将利用社区地球系统模型（CESM）和参与第五次耦合模式比对项目（CMIP5）的模型的输出来分离由于1)内部变率、2)模式结构和3)排放情景造成的预测不确定性。这项研究将弥合地球系统模型和观测研究之间的现有差距，以评估气候变化如何影响海洋生物地球化学。此外，该项目将支持一名早期职业科学家和一名研究生，研究人员将致力于通过科罗拉多大学博尔德分校、国家大气研究中心和威斯康星大学的各种项目指导本科生。用于预测未来由于自然或人为影响而发生的海洋生物地球化学变化的地球系统模式（ESM）模拟存在不确定性，特别是在区域尺度上。这是有问题的，因为随着海洋在当前气候下继续经历大规模的变化，对未来有一个准确的预测并能够在自然和人为强迫之间进行描绘是至关重要的。本研究旨在量化三个层面的不确定性：内部变异的不确定性、模式结构的不确定性和排放情景的不确定性。利用社区地球系统模式（CESM）和第五次耦合模式比对项目（CMIP5）模式的输出，本研究将评估不确定性随新模式变化的程度。此外，来自全球数据库、卫星和时间序列站点的观测结果将用于比较模型和评估预测一个地区生物地球化学的不同技能水平。研究人员还计划分解预测不确定性背后驱动机制的各个组成部分，以便未来的模型可以开始考虑这些因素。

The biogeochemistry of the oceans is undergoing large-scale changes due to anthropogenic climate change. Recent research suggests these changes are occurring significantly on regional scales, but due to model uncertainties, it is difficult to constrain the difference between anthropogenic and natural influences. In studying climate change and its effect on ocean biogeochemistry in the future, it is crucial to be able to distinguish between these influences; therefore, it is critical to identify and quantify the uncertainty in Earth System Models (ESMs). The researchers will use output from Community Earth System Model (CESM) and models participating in the Fifth Coupled Model Intercomparison Project (CMIP5) to isolate prediction uncertainty due to 1) internal variability, 2) model structure, and 3) emission scenario. This research will bridge an existing gap between Earth System Models and observational studies to assess how climate change will influence ocean biogeochemistry. Additionally, this project will support an early-career scientist and a graduate student, and the researchers are dedicated to mentoring undergraduate students through various programs at Colorado University - Boulder, National Center for Atmospheric Research, and the University of Wisconsin. Earth System Model (ESM) simulations used to predict future changes in ocean biogeochemistry attributed to either natural or anthropogenic influences suffer from uncertainties, particularly on regional scales. This is problematic because, as the ocean continues to undergo large-scale change under the current climate, it is crucial to have an accurate predictor of the future and to be able to delineate between natural and anthropogenic forcing. This research aims to quantify the uncertainty on three levels: uncertainty due to internal variability, model structure, and emission scenario. Using output from the Community Earth System Model (CESM) and models in the Fifth Coupled Model Intercomparison Project (CMIP5), this study will evaluate the degree to which uncertainty has changed with newer models. Additionally, observations from global databased, satellites, and time-series sites will be used to compare models and assess the varying levels of skill in predicting the biogeochemistry of a region. The researchers also plan to break down the various components of the driving mechanisms behind prediction uncertainty, so that future models can begin to take these factors into account.