气候变化领域集成服务门户(CCPortal): The Role of Isotope-Enabled GCM Complexity in Simulating Tropical Circulation Changes in High-CO2 Scenarios

CCPortal

DOI	10.1029/2020MS002163
	The Role of Isotope-Enabled GCM Complexity in Simulating Tropical Circulation Changes in High-CO2 Scenarios
	Hu J.; Dee S.; Nusbaumer J.
发表日期	2020
ISSN	19422466
卷号	12 期号:8
英文摘要	Stable water isotopes are data-rich tracers of the hydrological cycle, and, recently, the advent of isotope-enabled climate models has allowed for investigations into the utility of water isotopes for tracking changes in the large-scale atmospheric circulation. Among the suite of published isotope-enabled climate models, those with intermediate complexity offer the benefits of efficiency, allowing for long ensemble runs. However, the ability of these models to simulate the response to global warming with the same fidelity as state-of-the-art models is questionable. Here we evaluate an intermediate complexity model, SPEEDY-IER, in a high-CO2 scenario and compare its performance to an Intergovernmental Panel on Climate Change (IPCC)-class model, iCAM5. SPEEDY-IER can generally simulate changes in tropical circulation, the weakening of the Walker circulation, and the narrowing of the deep tropics. A deeper investigation of water isotope fields indicates SPEEDY-IER simulates qualitative trends in precipitation and vapor isotopes with fidelity, but it does not simulate amplitudes or spatial patterns of water isotope changes shown in iCAM5. This bias in SPEEDY-IER is mainly due to its coarse resolution and simplified convection scheme. We then modify the model by introducing condensation and detrainment in intermediate convection levels; this modification successfully improves SPEEDY-IER's simulation of water isotope fields, though the response of the Walker circulation to climate change is weakened. We demonstrate that evaluating water isotope fields reveals hidden biases in a climate model and guides improvements to the model's performance. Thus, the examination of water isotope fields and validation against available observations likely provides more stringent constraints for model physics. © 2020. The Authors.
语种	英语
scopus关键词	Carbon dioxide; Global warming; Isotopes; Tropics; Atmospheric circulation; Circulation changes; Hydrological cycles; Intergovernmental panel on climate changes; Intermediate complexity; Intermediate convections; Stable water isotopes; Stringent constraints; Climate models; atmospheric circulation; atmospheric convection; climate change; climate modeling; complexity; general circulation model; global warming; hydrological cycle; Intergovernmental Panel on Climate Change; scenario analysis; Walker circulation
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156668
作者单位	Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX, United States; Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, United States
推荐引用方式 GB/T 7714	Hu J.,Dee S.,Nusbaumer J.. The Role of Isotope-Enabled GCM Complexity in Simulating Tropical Circulation Changes in High-CO2 Scenarios[J],2020,12(8).
APA	Hu J.,Dee S.,&Nusbaumer J..(2020).The Role of Isotope-Enabled GCM Complexity in Simulating Tropical Circulation Changes in High-CO2 Scenarios.Journal of Advances in Modeling Earth Systems,12(8).
MLA	Hu J.,et al."The Role of Isotope-Enabled GCM Complexity in Simulating Tropical Circulation Changes in High-CO2 Scenarios".Journal of Advances in Modeling Earth Systems 12.8(2020).