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Changes in Arctic sea ice have exerted remarkably effects on the Eurasian climates, but it is unclear whether Arctic sea ice also contributes to Northwest China's ongoing summer drought. This study investigates the influence of the interannual variability of Arctic sea ice on the June drought in Northwest China from 1979 to 2021. It reveals that the early‐autumn sea ice in the East Siberian Sea is correlated with drought conditions in June in Northwest China, with a more pronounced connection during the period of 2000/2001–2020/2021 (P2) compared to 1979/1980–1999/2000 (P1). Mitigated drought in Northwest China is associated with anomalously high sea ice concentration (SIC) in the East Siberian Sea. Further analysis suggests that the strengthened link may be due to greater SIC variability in the East Siberian Sea during P2 than P1. In P2, positive early‐autumn SIC anomaly is linked to anomalous northeasterly winds, promoting drier soil and widespread cooling in the East European Plain. This dry soil signal may persist into the ensuing spring and early summer, inducing an anticyclonic circulation anomaly over Siberia, which could facilitate the water vapor convergence in Northwest China, thereby enhancing humidity conditions in the region. The insights from this study could offer valuable information for improved prediction of droughts in Northwest China. Plain Language Summary: This study examines the impact of Arctic sea ice changes on summer droughts in Northwest China. It was found that early‐autumn sea ice in the East Siberian Sea correlates with drought conditions in Northwest China. Increased sea ice concentration appears to help mitigate drought in Northwest China. This connection was stronger between 2000/2001 and 2020/2021 compared to 1979/1980 and 1999/2000. During 2000/2001–2020/2021, more sea ice leads to drier soil and cooling in the East European Plain, which may affect the following spring and early summer, thereby increasing humidity in Northwest China. These findings could improve predictions of drought conditions in Northwest China. Key Points: Study links East Siberian Sea ice to Northwest (NW) China's summer drought, especially after 2000Increased sea ice is linked to soil dryness and cooling in East European Plain, possibly subsequently enhance humidity in NW ChinaInsights on Arctic ice variability help predict NW China's droughts, aiding response strategies [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and heterogeneous interstitial lung disease with a median survival of 2–5 years. Though the diagnosis has been improved due to newly published guidelines, the recognition of the prognosis of IPF remains a challenge. Recently, several studies attempted to build prognostic models by extracting predictive variates from pulmonary function data, basic information, or chest computed tomography (CT) and CT-derived parameters with clinical characteristics. Artificial intelligence (AI) algorithms, including principal component analysis, support vector machine, random survival forest, and convolutional neural network, could be applied to the procedure of IPF prognostic model, that is, region of interest extraction, image feature selection, clinical feature selection, and model construction. Compared to human visualization, AI algorithms show a higher efficiency in calculating and extracting deep features and a lower inter-observer variation. Thus, this review provides a comprehensive CT evaluation of IPF prognostic models and discusses the role of AI in constructing IPF prognostic models. The potential improvements of AI in CT assessments, including time-series CT analysis, optimization of AI algorithms, utilization of multi-modal data, and discovery of new biomarkers through unsupervised algorithms, could be introduced to make a more accurate and convenient assessment for the prognosis of IPF patients. This review describes the status quo and future direction of AI applications in CT analysis for prognostic models of IPF. Take home message: The review summarizes the applications of CT and AI algorithms for prognostic models in IPF and procedures of model construction. It reveals the current limitations and prospects of AI-aid models, and helps clinicians to recognize the AI algorithms and apply them to more clinical work. [ABSTRACT FROM AUTHOR]

In this study, the mechanisms for the long‐lived and medium‐lived regional consecutive cloudy‐rainy events (RCCREs) in the Yangtze‐Huaihe River valley (YHRV) are investigated by comparing the influences of 10–30‐day and 30–90‐day intraseasonal oscillations (ISOs). The evolution of medium‐lived RCCREs is generally dominated by the 10–30‐day ISO, while the 10–30‐day and 30–90‐day ISOs synergistically contribute to the occurrence of long‐lived RCCREs. Further analysis reveals that, when the East Asian westerly jet (EAWJ) shifts northward to the north of YHRV, a RCCRE in the YHRV occurs in 2 days later. In the medium‐lived RCCREs, the EAWJ retreats southward rapidly; while in the long‐lived RCCREs, the stronger 30–90‐day ISO prevents the southward retreat of EAWJ, which favors the persistence of the RCCREs in the YHRV. The northward shifted EAWJ facilitates the RCCREs by modulating the secondary atmospheric circulation, consequently enhancing the moisture convergence and ascending motion anomalies over the YHRV. The RCCREs‐related precursor wave train originates from northern Europe with at least a 4‐day lead. The wave train propagates southeastward to excite an anomalous high over East Asia, which contributes to the northward shift of EAWJ and subsequently the occurrence of RCCREs. Different from the rapid weakness of the precursor wave train associated with the medium‐lived RCCREs, the precursor wave train associated with the long‐lived RCCREs can be maintained by the 30–90‐day ISO, which consequently leads to a persistence of the northward located EAWJ and long‐lived RCCREs in the YHRV. Plain Language Summary: Regional consecutive cloudy‐rainy events (RCCREs) have a disastrous impact on economy, agriculture, and natural environment over the Yangtze‐Huaihe River valley (YHRV). This study investigates the mechanisms contributing to the long‐ and medium‐lived RCCREs in the YHRV by comparing the role of 10–30‐day and 30–90‐day intraseasonal oscillations (ISOs). The medium‐lived RCCREs are dominated by the 10–30‐day ISO, while the long‐lived RCCREs are caused by a combination of the 10–30‐day and 30–90‐day ISOs. The East Asian westerly jet (EAWJ) plays a crucial role in RCCRE occurrence. When the EAWJ shifts northward, it triggers RCCREs by enhancing moisture convergence and ascending motion over the YHRV. The EAWJ retreats southward rapidly in the medium‐lived RCCREs. Conversely, the stronger 30–90‐day ISO prevents its southward retreat in the long‐lived RCCREs, favoring the persistence of RCCRE in the YHRV. Additionally, the precursor wave train originating from northern Europe contributes to the northward shift of the EAWJ and the occurrence of the RCCREs over the YHRV. Although both the long‐ and medium‐lived RCCREs exhibit similar precursor wave train, the influence of different ISOs varies, with the 30–90‐day ISO showing a larger impact on the precursor wave train and northward shift of the EAWJ in the long‐lived RCCREs. Key Points: Medium (long)‐lived RCCREs are mainly influenced by 10–30‐day intraseasonal oscillation (ISO) (both 10–30‐day and 30–90‐day ISOs)In the long (medium)‐lived RCCREs, the East Asian westerly jet (EAWJ) remains stable (retreats southward rapidly) after shifting northwardThe precursor wave train of the medium‐lived RCCREs weakens rapidly, while that of the long‐lived RCCREs is maintained by 30–90‐day ISO [ABSTRACT FROM AUTHOR]

This study investigates the influences of intraseasonal oscillation on two types of regional extreme consecutive dry days events (RECDD) in spring over Southern China (SC). For type‐1 RECDD occurring in entire SC, the 7–25 days and 25–90 days high over Lake Balkhash‐Baikal are important. The 7–25 days high first causes lower‐tropospheric northerlies and moisture deficit in SC, then propagates to Yangtze River Basin and causes lower‐tropospheric warming and decaying moisture deficit in SC. These processes favor dry condition in SC for 1 week. In comparison, the 25–90 days high and associated lower‐tropospheric warming and moisture deficit in SC favor dry condition there for more than one week. For type‐2 RECDD occurring in the southern part of SC, the 7–25 days and 25–90 days high over Northeast Asia are important. The 7–25 days high contributes for one week. It first causes lower‐tropospheric anticyclone around the East China Sea and south‐negative–north‐positive moisture pattern in SC, then propagates to the Sea of Japan and causes lower‐tropospheric south‐warming–north‐cooling pattern and decaying south‐negative–north‐positive moisture pattern in SC. In comparison, the 25–90 days high and associated lower‐tropospheric south‐warming–north‐cooling pattern and south‐negative–north‐positive moisture pattern in SC favor south‐dry–north‐wet pattern there for more than one week. Moreover, the 7–25 days low and decaying 25–90 days high over Lake Balkhash‐Baikal, concurring with 7–25 days low over Bay of Bengal, favor the end of type‐1 RECDD; the 7–25 days low and decaying 25–90 days high over Northeast Asia favor the end of type‐2 RECDD. Plain Language Summary: The extreme consecutive dry days with long duration could increase the risk of drought, even if the mean precipitation does not show significant change. In this study, we identify two types of regional extreme consecutive dry days events in spring over Southern China (type‐1 occurs in entire Southern China, type‐2 occurs in southern part of Southern China), with the aim of understanding the direct physical processes responsible for the persistence of extreme consecutive dry days. The results show that anomalous high over Lake Balkhash‐Baikal/Northeast Asia on two time‐scales (7–25 days and 25–90 days) are important for the persistence of type‐1/type‐2 events. In comparison, the 7–25 days high favors the persistence of regional events for approximately one week, whereas the 25–90 days high favors longer. Moreover, the 7–25 days low and decaying 25–90 days high over Lake Balkhash‐Baikal, combined with 7–25 days low over Bay of Bengal, provide a favorable condition for the end of type‐1 events. The 7–25 days low and decaying 25–90 days high over Northeast Asia favor the end of type‐2 events. Key Points: Two types of regional extreme consecutive dry days events in Southern China (SC) are identified in this study7–25 days high over Lake Balkhash‐Baikal/Northeast Asia favors type‐1/type‐2 events for one week, and 25–90 days high over there favors longer7–25 days low over Lake Balkhash‐Baikal/Northeast Asia, combined with decaying 25–90 days high there, favors the end of type‐1/type‐2 events [ABSTRACT FROM AUTHOR]