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Anthropogenic climate warming is predicted to increase the intensity of global tropical cyclones (TCs) on decadal timescales, known as the 'temperature-TC intensity' paradigm. However, no proxy is currently available to directly quantify TC intensity in the northwestern Pacific region over centennial to millennial timescales. Here, we reconstruct the intensity of past TCs inferred from event-beds detected in two sedimentary systems in eastern China spanning approximately 1910 to 645 yr BP using an instrumental-calibrated technique, thereby encompassing a sufficiently wide range of temperatures to test the paradigm in the time domain. Intriguingly, our two intensity indices, based on flooding depth and wind speed, provide the initial quantitative evidence that TC intensity in eastern China has been anomalously weak since around 1485 ± 45 yr BP, with a reduction of approximately 30 ± 8% in intensity, despite no concurrent temperature shift. This reduction appears to have been pre-conditioned by a combined influence of a weaker El Niño-Southern Oscillation, a stronger Atlantic Meridional Overturning Circulation, and an increased level of Saharan dust. We suggest that the magnitudes of these factors may have crossed a tipping point and have not reverted to their pre-shift levels since that time, resulting in their impact on TC intensity exceeding that of temperature by triggering changes in the oceanic and atmospheric state within the tropical Pacific region where TCs originate. [ABSTRACT FROM AUTHOR]

Frequency changes in intense typhoons are of great concern to modern society. However, current understanding of the influence of climate on typhoon activity on the millennial scale is restricted by the sparseness of pre‐observational reconstructions in the north‐western Pacific. This study presents a 5500 year long typhoon record from the Jiangsu coast that provides the first >2 ka record in eastern China. Variations in the D90 grain size are the best predictor of recent typhoons in a second short high‐resolution core. Comparison with other typhoon records from south‐eastern China establishes a China millennial typhoon variability index during the middle to late Holocene, with maxima at ca 4750 ± 170, 3500 ± 220, 1500 ± 480 and 250 ± 170 yr bp and minima at ca 5200 ± 300, 4150 ± 430, 2600 ± 650 and 750 ± 270 yr bp. Peaks in typhoon activity in south‐eastern China (compared with Japan) correlate with damped (enhanced) El Niño–Southern Oscillation and weak (strong) East Asian Summer Monsoon, indicating a seesaw pattern in typhoon activity between the two regions. A shift in typhoon frequency pattern was also identified around 2000 yr bp in south‐eastern China, with subsequent more frequent typhoon activity. At that time there was sustained Atlantic Meridional Overturning Circulation reduction and its associated El Niño–Southern Oscillation enhancement, so Atlantic Meridional Overturning Circulation‐driven El Niño–Southern Oscillation changes are likely to be the major cause of the significant increase in typhoon activity since 2000 yr bp, resulting in the 1500 ± 480 and 250 ± 170 yr bp China millennial typhoon variability peaks. To accurately predict changes in intense typhoon activity, it is therefore important to understand how the Atlantic Meridional Overturning Circulation and El Niño–Southern Oscillation will respond to future climate change. [ABSTRACT FROM AUTHOR]

There are concerns that intense tropical cyclones (TCs) are expected to become more frequent and powerful in warming climates. However, the long-term trend of TC activities, the spatiotemporal variability of such trends across different latitudes of the Western North Pacific (WNP), and the drives of the variability remain unclear. Here, we present a reconstruction of a 1600-year paleo-TCs activity using a sediment core taken in Li'an Lagoon located in southeastern Hainan Island, South China Sea. We used muti-dating methods (210Pb and AMS 14C dating) for age control and muti-proxy analysis (XRF geochemical element scanning and grain size analysis) for identifying periods of frequent intense TC activities. Based on an updated compilation of basin-wide paleo-TC records, we confirm that there exists a seesaw pattern of intense TC frequency between low and middle latitude in the WNP. Comparing with global and regional paleoclimate proxies, we propose that the basin-wide latitudinal TC activity variation in the WNP can be linked to the migration of Western Pacific Subtropical High (WPSH) and its associated high-latitude forcings (e.g., NAO) and low-latitude internal variability forcings (i.e., El Niño Southern Oscillation, sea surface temperature (SST)). More intense TC will occur at low latitudes in the future, though with less frequency. • A 1600 years high-resolution paleo-TCs records are reconstructed. • A clearly seesaw pattern were identified between TC activity at low and middle latitude over the WNP were found. • WPSH play an intermediate regulation role in controlling the TC latitudinal shift. [ABSTRACT FROM AUTHOR]

Among all marine hazards, storm surges cause the most severe damage, and East Asia is one of the regions in the world most affected by tropical cyclones (TCs). With the increase in global mean temperature, the future changes of tropical cyclone (TC) activities are of great concern in East Asian countries. However, due to the inconsistency among different TC datasets, there is no uniform understanding of the spatial and temporal distribution and trends of TC activities in the eastern sea area of China (ESAC). In this study, all TC wind fields affecting ESAC during 1949–2019 were calculated using the Fujita-Takahashi formula, and a new TC dataset with a spatial resolution of 0.1° × 0.1° was thus obtained. Based on this dataset, the spatial-temporal variations of TC activity were analyzed. Three stages (1949–1967, 1968–1993, 1994–2019) of TC activities in ESAC can be identified using Mann Kendall Trend Test, which is closely related to El Niño-Southern Oscillation, sunspot activity, and Pacific Decadal Oscillation. A comparison of the accumulative number and duration of TCs in the three stages shows increasing trend toward the coasts and an northward. To address the issue of shelf storm deposition records on ESAC, we compared the published storm depositional records retrieved from several cores with typhoon impact data from the same sites based on the dataset of this study. We found that the preservation potential of the storm deposition record on ESAC ranged from 8% to 33%, with a high preservation potential in shallow water. These findings reveal the distribution and variability of TC impacts, which can be used to provide a scientific basis for disaster prevention and mitigation planning and adjustment of key coastal protection zones, as well as to evaluate the value of marine sedimentary records better. We have established a new and more comprehensive dataset (0.1° × 0.1°) to analyze the spatial-temporal distribution of tropical cyclone(TC) activity on the seas. Also due to the latitudinal and longitudinal effects of TC effect, the coastal cities in northern China may suffer from more severe storm surge disasters in the future. We also included sedimentary records to help us understand more ancient TC activity. [Display omitted] • We provide a new high-resolution (0.1° x 0.1°) and more detailed dataset of tropical cyclones.. • Coastal cities in northern China are likely to suffer from more severe storm surge disasters in the future. • The tropical cyclone dataset coupled with the sedimentary record can provide a better understanding of paleostorm activity. [ABSTRACT FROM AUTHOR]

Climate change and human activity have exerted significant influences on the sediment load and channel morphology of the Changjiang River system, China. However, our knowledge of their influence on flood regime on the centennial to millennial timescales remains limited, and this is mainly because of the difficulty in directly determining the long-term hydrological variability of the Changjiang River over the period before hydrological gauges were established. Based on multiproxy analysis that combines chronological, sedimentological, and geochemical analysis of a 4.8-m-long sediment core retrieved from the subaqueous delta of the Changjiang River, this study establishes a flood history for the Changjiang River during the late Holocene. Our palaeoflood reconstruction revealed 14 multi-decadal periods of extreme floods (19–66 BCE, 25–80, 255–350, 415–475, 550–710, 740–835, 970–990, 1080–1130, 1170–1235, 1275–1390, 1440–1500, 1560–1730, 1810–1830, and 1950–2011 CE). These flood units match well with the observed large floods, documentary records of floods, and sedimentary flood deposits, confirming that the coarse units in the sequence are flood-derived and are regionally representative. Comparing with regional and global palaeoclimate records indicates that major flood events of the Changjiang are strongly modulated by the Asian summer monsoon and the El Niño–Southern Oscillation (ENSO), but that anthropogenic impacts (e.g. artificial channelization and land clearance) have also greatly amplified the flooding frequency over the past 600 yr. • We report a history of extreme flood events on the Chanjiang River over the past 2000 yr. • Periods of increased extreme flood activity in the Changjiang River typically coincide with El Niño periods and weak EASM phases. • Human modifications have greatly amplified flood activities in the Changjiang River over the past 600 yr. [ABSTRACT FROM AUTHOR]

The link between tropical cyclone (TC) activity in the South China Sea (SCS) and global climate change is commonly debated and there is a clear need for long-term geological records of TC activity if we are to clarify this connection. Multi-millennial, high-resolution paleo-storm records from the SCS are rare in the region and this causes difficulties for those exploring potential climate drivers of TC variability over centennial to millennial timescales and reduces our ability to fully assess the risks associated with future TC activity. This paper presents an age-constrained, mud-dominated sedimentary sequence from a coastal lagoon on Hainan Island, China. Multiproxy analyses incorporating chronological, lithological, sedimentological, and geochemical evidence were used to infer storm deposits preserved within the sequence and to reconstruct a time series of storm activity in the SCS during the mid-to-late Holocene. This long sedimentary record shows that TCs were highly active over the periods 5500 to 3500 and 1700 to 0 cal yrs. BP, and these periods contrast with a relatively quiet period 3500–1700 cal yrs. BP. An apparent inverse correlation between TC reconstructions from the SCS and those from the Korean Peninsula and Japan implies an oscillating pattern across the SCS and western North Pacific (WNP) over centennial to millennial timescales. A comparison between the sedimentary and paleoclimatic records implies that the El Niño–Southern Oscillation was not the only mechanism responsible for typhoon variability over the past 7500 cal yrs. BP, suggesting that other factors such as the thermal state of the western Pacific warm pool likely also had a strong influence on both SCS and WNP TC variability. • Sedimentological evidence from Hainan Island was used to reconstruct typhoon activity in the SCS over the mid–late Holocene. • There exists a well-defined seesaw pattern in storm activity across the WNP basin during the study period. • Periods of increased (reduced) storm activity in the SCS typically coincide with La Niña (El Niño) periods and warm (cold) phases of the WPWP during the mid-late Holocene. [ABSTRACT FROM AUTHOR]