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While a large latitudinal displacement of the westerly jet brings about disproportionate socioeconomic impacts over Northern Hemisphere midlatitude continents, it is not well understood as to whether the winter circulation will become wavier or less in response to climate change. Here, using observations and large ensembles of climate models, we show that changes in atmospheric waviness can be estimated from the optimal structures of the westerly jet for wavier circulation, which are obtained from an advection‐diffusion model. Thus, the changes in westerly jet structure in climate models under climate change provide a physical constraint on changes in atmospheric waviness, indicating that the North Atlantic wave activity will experience a robust decline in a warmer climate, while future North Pacific wave activity is obscured by model uncertainty rather than internal variability. These findings highlight the changes to jet stream structure as a constraint for regional circulation waviness in a changing climate. Plain Language Summary: A large latitudinal meandering of Northern Hemisphere winter circulation can induce stagnant weather that causes severe impacts on densely populated East Asia, Western North America, or Western Europe, yet whether the winter circulation will become wavier or less under climate change remains uncertain. Here we analyze observations and large ensembles of climate models and show that changes to atmospheric wave activity under climate change are largely constrained by changes to zonal advecting wind for the Lagrangian motion of air parcels in an advection‐diffusion model. This constraint further indicates a consistent decline in future waviness over the North Atlantic, while changes to future wave activity over the North Pacific are uncertain, due to model uncertainty rather than internal variability of the climate system. Key Points: Changes in atmospheric waviness can be roughly estimated by changes in zonal advecting wind in an advection‐diffusion modelChanges in the optimal structure of jet stream help constrain regional circulation waviness in a changing climateModel results suggest future waviness will robustly decline in North Atlantic but is less clear in North Pacific due to model uncertainty [ABSTRACT FROM AUTHOR]

Predicting how regional precipitation will respond to future warming is among the most challenging undertaking in climate change projection. Despite sustained efforts to improve modeling and understanding of precipitation, the overall uncertainty in projecting regional precipitation has not been reduced substantially. Here, the potential for more robust precipitation projections is demonstrated through the use of discriminating metrics to subsample a multimodel ensemble. Using a two‐dimensional metric of precipitation and its relationship with large‐scale circulation indices in East Asia, 31 models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) are classified into three groups. Models in the top performing group projected statistically significant increasing trends in precipitation and the regional precipitation patterns are more similar to each other than to the patterns in the bottom performing group. In contrast, models in the bottom performing group projected diverse responses, with overall small drying or no significant trends in precipitation. Plain Language Summary: Precipitation is a fundamental driver of land surface hydrology and water resources, but large biases in climate model simulations of precipitation and large uncertainties in the future projections hinder the use of climate models in climate impact studies. Metrics of precipitation used in climate model evaluation usually focus on different precipitation characteristics, while ignoring important physical mechanisms linking precipitation with its environments. In this study, a two‐dimensional metric is proposed to evaluate both the simulated precipitation and its relationship with large‐scale circulation patterns in East Asia. This metric is applied to the Coupled Model Intercomparison Project Phase 5 (CMIP5) models to classify 31 models into three groups based on model performances. The metric is able to discriminate model responses: models in the top performing group show more consistent and similar responses of precipitation to future warming, featuring larger increases of future precipitation than the CMIP5 ensemble mean over China. Key Points: A two‐dimensional metric is developed to evaluate precipitation and its relationships with the large‐scale circulation in climate modelsThe new metric identifies a subset of models skillful in simulating both precipitation and its relationship with the monsoon circulationThis subset of models projects a more robust and larger increase of future precipitation than the multimodel ensemble mean over China [ABSTRACT FROM AUTHOR]

ABSTRACT Background and Objective: Pemetrexed plus platinum has shown efficacy as a first-line treatment for advanced non-small cell lung cancer (NSCLC), but little is known about its efficacy and safety in East Asian patients. We report the final analysis of overall survival (OS) from a multicentre, randomized, phase II trial in chemotherapy-naive Chinese patients with advanced NSCLC. An additional meta-analysis was performed to systematically evaluate pemetrexed/platinum as first-line treatment for advanced NSCLC. Methods: Eligible patients received up to six cycles of pemetrexed, 500 mg/m2 plus cisplatin, 75 mg/m2 (day 1) or gemcitabine, 1000 mg/m2 (days 1 and 8) plus cisplatin, 75 mg/m2 (day 1). OS and toxicity were assessed. Results: A total of 254 patients were randomized, and 251 were eligible for inclusion in the efficacy and safety analyses. Median OS in the pemetrexed/cisplatin arm was 15.3 months, compared with 16.9 months in the gemcitabine/cisplatin arm [hazard ratio (HR) 1.09; 95% confidence interval (CI) 0.80-1.48; log-rank P = 0.4888). There was a trend towards improved survival in both arms. Patients in the pemetrexed/cisplatin arm showed a lower incidence of drug-related grade 3 to 4 leukopenia and thrombocytopenia. Meta-analysis showed that pemetrexed-platinum treatment was associated with 19% longer survival among females (HR 0.81; 95% CI 0.69-0.96) and 17% longer survival among patients with non-squamous cell lung cancer (HR 0.83; 95% CI 0.73-0.95). Conclusions: In Chinese patients with advanced NSCLC, pemetrexed/cisplatin treatment resulted in comparable OS outcomes and was better tolerated than gemcitabine/cisplatin. Meta-analysis supports the use of pemetrexed-platinum as first-line treatment for female patients and those with the non-squamous cell subtype of advanced NSCLC. [ABSTRACT FROM AUTHOR]

• Mud deposits provide a decadal-resolution record of the EAWM changes from 3500 to 1300 cal. yr BP. • A long-term progressively increased EAWM trend and 9 short-lived strong EAWM episodes. • The collapses of ancient Chinese dynasties corresponded to cold periods with strong EAWM. • EAWM-related temperature and precipitation changes affect ancient Chinese dynasties. Changes in paleoenvironments from 3500 to 1300 cal. yr BP have been documented by a high-resolution grain-size and organic carbon isotope record in core Z8 from the Shandong mud wedge in the southern Yellow Sea (YS). The sensitive grain-size component, sorting coefficients and δ13 C org values were used to identify the paleohydrologic variations and the intensity of the East Asian winter monsoon (EAWM). The coarse fraction of sediment, together with organic isotope and sea surface temperature (SST) data, shows a weak EAWM during 3500–2300 cal. yr BP, a gradual increase in the EAWM from 2300 to 1700 cal. yr BP and an enhanced EAWM since 1700 cal. yr BP. Superimposed on this general trend, several prominent short-lived strong EAWM episodes peaked at approximately 3300, 3100, 2900, 2750, 2620, 2220, 1900, 1700 and 1400 cal. yr BP. The paleoenvironmental record matches ancient Chinese historical climate records as well as socioeconomic changes, with lower economic levels occurring during stronger EAWM episodes. The results show that prosperous stages of ancient Chinese dynasties mainly occurred in weak EAWM periods, while collapses and/or changes in ancient Chinese dynasties generally occurred during cold periods with a strong EAWM. We suggest that the persistent short-lived strengthening of the EAWM could have exerted a remarkable influence on ancient agricultural societies through decreases in both winter temperature and monsoonal precipitation. [ABSTRACT FROM AUTHOR]