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

由于人为气候变化，海洋的地球化学正在发生大规模的变化。最近的研究表明，这些变化在区域尺度上发生得很大，但由于模型的不确定性，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地球化学的影响时，能够区分这些影响至关重要;因此，识别和量化地球系统模式（ESM）中的不确定性至关重要。研究人员将使用社区地球系统模型（CESM）和参与第五耦合模型相互比较项目（CMIP 5）的模型的输出来隔离由于1）内部变异，2）模型结构和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，以评估气候变化将如何影响海洋地球化学。 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州大学的各种项目指导本科生。地球系统模式（ESM）模拟用于预测未来海洋地球化学变化归因于自然或人为影响遭受不确定性，特别是在区域尺度上。这是有问题的，因为随着海洋在目前的气候下继续经历大规模的变化，至关重要的是要有一个准确的预测未来，并能够区分自然和人为强迫。本研究的目的是量化三个层次的不确定性：由于内部变异，模型结构和排放情景的不确定性。利用社区地球系统模型（CESM）和第五次耦合模型相互比较项目（CMIP 5）中的模型的输出，本研究将评估新模型的不确定性变化程度。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，并评估预测一个区域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.