Identifying Climate Model Biases in the Pattern of Ocean Warming and their Influence on Regional Climate Change

热带太平洋的地表温度观测显示，在过去的50年里，西太平洋的变暖速度高于东太平洋。然而，大多数最先进的气候模型显示了相反的情况。目前还不确定观察到的趋势是否会继续，或者海洋变暖模式最终是否会恢复到更像气候模型预测的模式。这些设想之间的差异是预测未来区域气候变化的一个主要不确定性来源，因为热带海洋不寻常的温度模式产生了影响全球区域气候的大规模大气波动扰动。该项目将利用气候模型和气候模型数据分析，以了解在最近的海洋变暖模式中气候模型与观测值之间存在差异的原因，了解导致不同气候模型预测未来海洋温度模式不同变化的过程，确定世界各地哪些区域的大气环流和降水预测可能受到热带太平洋气候模型偏差的影响，并了解将这些区域的变化与热带太平洋联系起来的过程。通过结合对热带太平洋在不同气候模型下未来如何变化的理解，以及对单个气候模型如何以及为什么与观测记录相比存在偏差的理解，这项研究有可能限制未来对海洋变暖模式的预测。改善对热带太平洋未来气候变化的制约，将反过来改善对北美等受热带太平洋发出的波浪扰动强烈影响的区域未来大气环流和区域气候变化的制约。这项工作将支持一名早期研究人员和一名研究生的职业发展，并包括通过华盛顿大学气候变化项目和西雅图太平洋科学中心的公共宣传活动。该项目弥合了基础科学问题之间的差距，这些问题涉及热带太平洋如何以及为什么对不同时间尺度的人为强迫做出反应，以及对美国西南部和其他受厄尔尼诺强烈影响的地区未来几十年水资源如何变化的更好预测的实际需要。这项研究还将在模拟当前气候和模拟气候趋势时，识别和调查气候模型偏差的原因。这项工作将为气候模型开发人员提供有价值的信息，他们正在努力解决这些偏见并改进气候模型，以及为使用气候模型的广大科学家了解和规划气候变化的区域影响提供有价值的信息。该项目将有助于培养下一代气候科学家。该项目的结果将通过出版物、会议报告、新闻稿和公众宣传广泛传播。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Surface temperature observations in the tropical Pacific Ocean show a higher rate of warming over the last 50 years in the West Pacific than in the East Pacific. However, most state-of-the-art climate models show the opposite. It is uncertain if the observed trend will continue or if the ocean warming pattern will eventually revert to something more like climate model projections. The difference between these scenarios is a primary source of uncertainty in projected future changes in regional climate because unusual temperature patterns in the tropical oceans generate large-scale atmospheric wave disturbances that influence regional climate throughout the globe. This project will use climate modeling and analysis of climate model data to understand the causes of the discrepancy between climate models and observations in the recent pattern of ocean warming, to understand the processes that lead different climate models to project different future changes in the ocean temperature pattern, to identify regions worldwide where atmospheric circulation and precipitation projections could be affected by climate model biases in the tropical Pacific, and to understand the processes linking changes in these regions to the tropical Pacific. By combining an understanding of how the tropical Pacific Ocean changes in the future in different climate models with an understanding of how and why individual climate models are biased compared to the observational record, this research has the potential to constrain future projections of ocean warming patterns. Improved constraints on future climate change in the tropical Pacific will in turn improve constraints on future changes in atmospheric circulation and regional climate in regions such as North America that are strongly influenced by wave disturbances emanating from the tropical Pacific. The work will support the career development of an early-career researcher and a graduate student as well as include public outreach activities through the University of Washington Program on Climate Change and the Pacific Science Center in Seattle.This project bridges the gap between fundamental science questions on how and why the tropical Pacific responds to anthropogenic forcing on different timescales with the practical need for better projections of how water resources will change in the coming decades in the U.S. Southwest and other regions that are strongly influenced by El Niño. This research will also identify and investigate the causes of climate model biases, in their simulation of the current climate and their simulation of climate trends. This work will provide valuable information for climate model developers, who are working to address these biases and improve climate models, and for the large community of scientists using climate models to understand and plan for the regional impacts of climate change. This project will help train the next generation of climate scientists. The results of this project will be disseminated widely through publications, conference presentations, press releases, and outreach to the public.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.