Possible mechanisms for persistent anomalous rainfall over the middle and lower reaches of <scp>Yangtze River</scp> in winter 2018/2019

Da-Quan, Zhang; Chen, Lijuan

doi:10.1002/joc.7197

Cited by 6 publications

(3 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The intensification of positive SST anomalies in the mid-latitudes of the North Atlantic (figures 3(e) and (f)), accompanied by the positive phase of the North Atlantic oscillation in August, contributed to the propagation of the SRP. The SRP also modulates the intensity and location of both the SAH and WNPSH (Kosaka et al 2012, Ren et al 2015, Cen et al 2020, Zhang and Chen 2021. The correlation coefficient between the SRP index and the longitude of SAH center in August was −0.39, whereas the correlation coefficients between the SRP index and the intensity and longitude of the western end of the WNPSH were −0.33 and 0.45, passing the significance test at 90 and 95%, respectively.…”

Section: Climate Contributor To the Intensification Of Heat Wave In L...mentioning

confidence: 98%

Why was the heat wave in the Yangtze River valley abnormally intensified in late summer 2022?

Da-Quan

Chen

Yuan

et al. 2023

Environ. Res. Lett.

Self Cite

View full text Add to dashboard Cite

A record-breaking heat wave hit the Yangtze River valley during the boreal summer of 2022, and caused severe social and economic losses. One prominent feature of this long-lived heat event was its persistence and abnormal intensification in August. This study investigated the physical mechanisms be responsible for the intensification of this heat event in late summer under the background of a La Niña event. The prolonged heat event was directly related to the intensification and westward extension of the western North Pacific subtropical high, which can be attributed to the synergistic effects of an anomalous western North Pacific anticyclone and the eastward extension of the South Asian high in the upper troposphere. The anomalous anticyclone in the western North Pacific, which was induced by negative sea surface temperature anomalies in the central tropical Pacific, strengthened in August. The positive sea surface temperature anomaly in the western Pacific warm pool and enhanced in-situ convection led to anomalous high pressure over the Yangtze River valley via the local meridional circulation. Atmospheric convergence and descending motion over the Yangtze River valley was amplified in August as a result of the zonal shift in the South Asian high from the Iranian Plateau to the Tibetan Plateau. The Silk Road pattern index of August 2022 was the lowest since the 1990s. The abnormal negative phase of the Silk Road pattern contributed to both the zonal shift in the South Asian high and the westward extension of the western North Pacific subtropical high, which led to the abnormal intensification of the heat event over the Yangtze River valley in August 2022.

show abstract

Section: Climate Contributor To the Intensification Of Heat Wave In L...mentioning

confidence: 98%

Why was the heat wave in the Yangtze River valley abnormally intensified in late summer 2022?

Da-Quan

Chen

Yuan

et al. 2023

Environ. Res. Lett.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, the catchment area of the Yangtze River is the most concentrated area of freshwater lakes in China. Most parts of the study area are relatively flat and low-lying, including the famous Poyang and Dongting Lakes [44,45].…”

Section: Study Areamentioning

confidence: 99%

Monitoring Meteorological Drought in Southern China Using Remote Sensing Data

Liu

Huang

Cheng³

et al. 2021

Remote Sensing

View full text Add to dashboard Cite

Severe meteorological drought is generally considered to lead to crop damage and loss. In this study, we created a new standard value by averaging the values distributed in the middle 30–70% instead of the traditional mean value, and we proposed a new index calculation method named Normalized Indices (NI) for meteorological drought monitoring after normalized processing. The TRMM-derived precipitation data, GLDAS-derived soil moisture data, and MODIS-derived vegetation condition data from 2003 to 2019 were used, and we compared the NI with commonly used Condition Indices (CI) and Anomalies Percentage (AP). Taking the mid-to-lower reaches of the Yangtze River (MLRYR) as an example, the drought monitoring results for paddy rice and winter wheat showed that (1) NI can monitor well the relative changes in real precipitation/soil moisture/vegetation conditions in both arid and humid regions, while meteorological drought was overestimated with CI and AP, and (2) due to the monitoring results of NI, the well-known drought event that occurred in the MLRYR from August to October 2019 had a much less severe impact on vegetation than expected. In contrast, precipitation deficiency induced an increase in sunshine and adequate heat resources, which improved crop growth in 78.8% of the area. This study discusses some restrictions of CI and AP and suggests that the new NI index calculation provides better meteorological drought monitoring in the MLRYR, thus offering a new approach for future drought monitoring studies.

show abstract

“…Thus, both of the variation in the intensity and meridional shift of the EASJ are important to the occurrence of rainfall over southern China (Zhang et al, 2019;Liu et al, 2022). The EASJ was also an important bridge that linked the remote upstream disturbance to the winter precipitation over East Asian (Watanabe, 2004;Hu et al, 2018;Zhang and Chen, 2021). Previous studies have shown that a Rossby wave train originating from the North Atlantic or Mediterranean region may propagate eastward along the subtropical westerly jet into East Asia and have an important role in generating circulation patterns conducive to persistent heavy rainfall events over southern China (Zong et al, 2012;Li and Sun, 2015;Ding and Li, 2017;Li et al, 2017;Huang et al, 2019;Li et al, 2020;Chen and Li, 2022;Tan et al, 2022).…”

Section: Introductionmentioning

confidence: 99%

Role of the subtropical westerly jet wave train in the eastward-moving heavy rainfall event over southern China in winter: A case study

Yin

Yuan²,

Peng³

et al. 2023

Front. Earth Sci.

View full text Add to dashboard Cite

Under the wintertime background of westerly flows, heavy rainfall often occurs first over southwestern China and then spreads eastward downstream to southeastern China, causing serious impact on a large scope of southern China. By using the synoptic diagnosis and dynamic analysis methods, we examined a typical eastward-moving heavy rainfall event that occurred over southwestern China on January 8–9, 2015 and then gradually spread eastward to southeastern China on January 10–13. The results show the important role of the Rossby wave train propagating along the subtropical westerly jet in “pushing” the eastward movement of heavy rainfall over southern China. The remote Rossby wave train influenced the variation of heavy rainfall by modifying the local circulation. The Rossby wave train can change the morphology of the East Asian subtropical jet via wave—jet interactions and modify the related secondary upward circulation in the entrance area of the jet, providing favorable dynamic conditions for the occurrence of heavy rainfall. The Rossby wave train can also influence the low-level south branch trough by modifying the associated baroclinic energy conversion process under a background of deep layer subsidence, which favors the transport of plentiful water vapor to the region of heavy rainfall over southern China. The eastward-propagating Rossby wave train pushed the upper level East Asian subtropical jet and the lower level south branch trough as a whole while simultaneously moving east, which caused the region of heavy rainfall to move from southwestern to southeastern China. These results will help to provide a scientific basis for forecasting winter rainfall over southern China.

show abstract

Possible mechanisms for persistent anomalous rainfall over the middle and lower reaches of Yangtze River in winter 2018/2019

Cited by 6 publications

References 50 publications

Why was the heat wave in the Yangtze River valley abnormally intensified in late summer 2022?

Why was the heat wave in the Yangtze River valley abnormally intensified in late summer 2022?

Monitoring Meteorological Drought in Southern China Using Remote Sensing Data

Role of the subtropical westerly jet wave train in the eastward-moving heavy rainfall event over southern China in winter: A case study

Contact Info

Product

Resources

About