المؤلفون: Zhang, Y, Andrade, T, Ravelo, AC, Gong, L, Holbourn, A, Connock, G, Liu, XL, Aiello, IW

المصدر: Paleoceanography and Paleoclimatology. 38(10)

مصطلحات موضوعية: Earth Sciences, Physical Geography and Environmental Geoscience, Geology, Climate Action, Life Below Water, tropical hydroclimate, tropical productivity, northwest Australia, the Indonesian throughflow, mid-early Pleistocene, Australian monsoon

الوصف: Studying tropical hydroclimate and productivity change in the past is critical for understanding global climate dynamics. Northwest Australia is an ideal location for investigating Australian monsoon dynamics, the variability of the Indonesian Throughflow (ITF), and their impact on past productivity and Pacific warm pool evolution, which remain poorly understood during the 40 kyr world in the mid-early Pleistocene. In this study, we present multi-proxy records from International Ocean Discovery Program (IODP) Site U1483 in the Timor Sea spanning the last 2,000 ka, including orbitally-resolved records from the 40 kyr world between 2,000 and 1,300 ka. Our results suggest that northwest Australia underwent a step of increased aridification and that productivity in the Timor Sea declined during the transition from ∼1,700 to ∼1,400 ka. We attribute this aridification to the reduced moisture supply to this region caused by the ITF restriction and warm pool contraction. We ascribe the declined productivity to a decrease in the nutrient supply of the Pacific source water associated with global nutrient redistribution. At orbital timescale, multiple mechanisms, including sea level changes, monsoon, and the Intertropical Convergence Zone (ITCZ) dynamics, and variations in the ITF and Walker circulation could have controlled variations of productivity and terrigenous input in the Timor Sea during the 40 kyr world. Our bulk nitrogen and benthic carbon isotope records suggest a strong coupling to biogeochemical changes in the Pacific during this period. This research contributes to a better understanding of tropical hydroclimate and productivity changes during the 40 kyr world.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/2bv3h618Test

المؤلفون: Matsuzaki, Kenji M

مصطلحات موضوعية: Australian Monsoon Monsoon, Indonesian Throughflow, Mid Pleistocene Transition, Radiolarians, Summer sea surface temperature, Integrated Ocean Drilling Program / International Ocean Discovery Program IODP

الوصف: Here we submitted modern core top radiolarian assemblage dataset in the Northwestern Australian Margin. The sample were collected during the German Sonne R/V Expedition SO 257. The dataset served as a calibration dataset to estimate past Summer Sea Surface Temperature (SST) of the Past using radiolarian species. We also submit herein IODP 363 Site U1483 (the Timor Sea), radiolarian assemblage data from the time interval between 500 and 1600 ka to discuss the impact of the Mid Pleistocene Transition on regional climate/ocean system such as the Indonesian Throughflow and the Australian Monsoon. For do so, we estimate the summer SST between 500 and 1600 ka relying on the SO 257 core top radiolarian assemblages. ...

وصف الملف: application/zip

العلاقة: https://dx.doi.org/10.1016/j.epsl.2023.118437Test

الإتاحة: https://doi.org/10.1594/pangaea.96399710.1016/j.epsl.2023.118437Test

المؤلفون: Cowan, Tim, Hinds, Emily, Marshall, Andrew G., Wheeler, Matthew C., Burgh-Day, Catherine

مصطلحات موضوعية: Australian monsoon, beef cattle, Bureau of Meteorolo, monsoon retreat, El Niño–Southern Oscillation, Madden–Julian Oscillation, prediction, wet season

الوصف: According to the Australian Bureau of Meteorology, the northern Australian wet season extends through to April, which also formally marks the end of Australia’s tropical cyclone season. Mid-autumn is when the tropical dry season transition period begins, when crop farmers prepare land for annual crops or pasture–fodder harvest, or when beef cattle producers make decisions regarding stock numbers and feed rationing. Potentially knowing if the last rains of the wet season will be later or earlier than normal would be valuable information for northern sectors such as agriculture, infrastructure and tourism. The Bureau of Meteorology provides seasonal forecasts of the Northern Rainfall Onset – the date when a location has accumulated 50 mm of rain from 1 September – yet there is currently no prediction of the rainy season retreat (the Northern Rainfall Retreat, NRR). In this study, we draw on three different NRR definitions and investigate how they vary with the El Niño–Southern Oscillation and the Madden–Julian Oscillation (MJO). In general, retreats occur ~1 week later than normal across the far northern tropics following La Niña events, but little change from normal occurs for El Niño. Although most retreats occur when the MJO is weak, if the MJO is active, retreats are mostly observed in phases 6 and 7, when convection is passing through the western Pacific. Utilising the Bureau of Meteorology’s sub-seasonal to seasonal forecast system, ACCESS-S2, we show that the model has some skill in forecasting the NRR across the far northern regions at a lead time of ~2.5 months, but poor skill in the subtropics and arid locations. Verification of the 2023 NRR forecasts, highlights the challenges of predicting the timing and magnitude of daily rainfall at such a long lead time.

وصف الملف: application/pdf

العلاقة: https://research.usq.edu.au/download/9ac300d2cf0ff0d715f8dc5be3afefe6f498817961572bcde807e87e86173e6b/7328360/ES23022.pdfTest; https://doi.org/10.1071/ES23022Test; Cowan, Tim, Hinds, Emily, Marshall, Andrew G., Wheeler, Matthew C. and Burgh-Day, Catherine. 2024. "Observing and forecasting the retreat of northern Australia’s rainy season." Journal of Southern Hemisphere Earth Systems Science. 74 (1). https://doi.org/10.1071/ES23022Test

الإتاحة: https://doi.org/10.1071/ES23022Test
https://research.usq.edu.au/item/z5qvy/observing-and-forecasting-the-retreat-of-northern-australia-s-rainy-seasonTest
https://research.usq.edu.au/download/9ac300d2cf0ff0d715f8dc5be3afefe6f498817961572bcde807e87e86173e6b/7328360/ES23022.pdfTest

المؤلفون: Chen, Mengyan, Yu, Jin‐Yi, Wang, Xin, Chen, Sheng

المصدر: Geophysical Research Letters. 48(14)

مصطلحات موضوعية: Climate Action, EP El Nino, CP-I El Nino, CP-II El Nino, Australian monsoon, Pacific Meridional Mode, Meteorology & Atmospheric Sciences

الوصف: This study analyzes two subtypes of Central Pacific (CP) El Niño and shows that they possess different sea surface temperature evolution patterns in the Indo-Pacific Oceans, distinct generation mechanisms, and can respond differently to global warming. The CP-I type is triggered in the tropical western Pacific by the weaker-than-normal Australian winter monsoon (AM) through a subsurface thermocline mechanism and is accompanied by significant Indian Ocean warming. The CP-II type onsets in the subtropical North Pacific by the Pacific Meridional Mode (PMM) through a surface coupling mechanism and is accompanied by weak warming anomalies in the Indian Ocean. Two climate models projections indicate that the CP-II type may occur more frequently than the CP-I type in the future due to changes in PMM and AM activities, which should weaken El Niño influences on the Indian Ocean and result in more El Niño events that onset from the North American coast.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/3hf434kpTest

المؤلفون: Noir P. Purba, Ibnu Faizal, Hind Azidane, Alexander M.A. Khan, Lantun P. Dewanti, Sanny T. Utami, Kalysta Fellatami

المصدر: Data in Brief, Vol 50, Iss , Pp 109609- (2023)

مصطلحات موضوعية: Regional climate, Wind pattern, Asian-Australian monsoon, Weather station, Computer applications to medicine. Medical informatics, R858-859.7, Science (General), Q1-390

الوصف: This paper presents a collection of small-scale atmospheric datasets obtained from a PCE-FWS 20 N weather station in Pangandaraan, a region situated in the southern part of Java Island. The datasets cover a period from March 2022 to April 2023, with hourly measurements of air temperature, humidity, wind speed, wind direction, and daily rainfall. The instrument was cleaned and calibrated every three months according to the manufacturer's guidelines. Every week the data was downloaded from the memory card, resulting in a total of 48,468 data points available in a publicly accessible repository. The collected data were organized into .csv format and visualized to facilitate analysis. Our study aims to explore the microclimate of Pangandaraan over an extended period and highlights its potential applications in various fields, such as applied oceanography, meteorology, fishing grounds, and agriculture.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2352340923006960Test; https://doaj.org/toc/2352-3409Test

الوصول الحر: https://doaj.org/article/bc0997295e934e259c7da37c1c9dccb4Test

المؤلفون: Zhi Li, Zecheng Xu, Yunxia Zheng, Yue Fang

المصدر: Frontiers in Marine Science, Vol 10 (2023)

مصطلحات موضوعية: Indian Ocean Dipole (IOD), extreme event analysis, Asian–Australian monsoon, easterly wind anomaly, heat budget analysis, Science, General. Including nature conservation, geographical distribution, QH1-199.5

الوصف: The Indian Ocean Dipole (IOD) is one of the dominant interannual variabilities in the Indian Ocean (IO), and an extreme IOD, in particular, has dramatic effects on the weather, agriculture, and ecosystem around it. Therefore, the formation of an extreme IOD has been a worldwide research focus. Among 13 positive IOD (PIOD) events, two type-east and two type-comparable PIODs developed into extreme events during the 1960–2020 period. This investigation focuses on the cause of the formation of the type-east extreme PIOD, as previous studies have discussed the origin of the type-comparable extreme PIOD. Composite analysis showed that, as an entity, the strong East Asian and Australian monsoon (EAAM) may result in an evident easterly wind anomaly around the Indonesian region of the Marine Continent during May to August of the years when type-east PIODs occurred. The easterly wind anomaly associated with the EAAM was stronger in the extreme IOD group, whereas it was relatively weak in the regular group. The difference in the easterly wind anomaly between the extreme and regular groups could result in a vertical motion anomaly by enhancing the anomalous westward current. The stronger vertical motion created an upwelling in the deep-layer cold water, resulting in a more distinct difference in the vertical temperature gradient. All these conditions promoted the transformation of the type-east PIODs that occurred in 1961 and 1994 into extreme events and are indicative of the importance of vertical advection terms in the formation of type-east extreme PIODs. This study reveals the cause of the formation of type-east extreme PIODs, which will be helpful in understanding IOD diversity.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fmars.2023.1106130/fullTest; https://doaj.org/toc/2296-7745Test

الوصول الحر: https://doaj.org/article/e4ef4951be4e427ea20c8f47248fe1c6Test

المؤلفون: Heidemann, Hanna, Cowan, Tim, Henley, Benjamin J., Ribbe, Joachim, Freund, Mandy, Power, Scott

مصطلحات موضوعية: Australian monsoon, climate change, climate variability, ocean-atmosphere interactions, rainfall, rainfall driver, rainfall projection

الوصف: The Australian monsoon delivers seasonal rain across a vast area of the continent stretching from the far northern tropics to the semi-arid regions. This article provides a review of advances in Australian monsoon rainfall (AUMR) research and a supporting analysis of AUMR variability, observed trends, and future projections. AUMR displays a high degree of interannual variability with a standard deviation of approximately 34% of the mean. AUMR variability is mostly driven by the El Niño-Southern Oscillation (ENSO), although sea surface temperature anomalies in the tropical Indian Ocean and north of Australia also play a role. Decadal AUMR variability is strongly linked to the Interdecadal Pacific Oscillation (IPO), partially through the IPO's impact on the strength and position of the Pacific Walker Circulation and the South Pacific Convergence Zone. AUMR exhibits a century-long positive trend, which is large (approximately 20 mm per decade) and statistically significant over northwest Australia. The cause of the observed trend is still debated. Future changes in AUMR over the next century remain uncertain due to low climate model agreement on the sign of change. Recommendations to improve the understanding of AUMR and confidence in AUMR projections are provided. This includes improving the representation of atmospheric convective processes in models, further explaining the mechanisms responsible for AUMR variability and change. Clarifying the mechanisms of AUMR variability and change would aid with creating more sustainable future agricultural systems by increasing the reliability of predictions and projections. This article is categorized under: Paleoclimates and Current Trends > Modern Climate Change.

وصف الملف: application/pdf

العلاقة: https://research.usq.edu.au/download/066bd294a4370f41373511346fdaf87c049d3f717c9d8dfca64451e653f00294/8249233/WIREs%20Climate%20Change%20-%202023%20-%20Heidemann.pdfTest; https://doi.org/10.1002/wcc.823Test; Heidemann, Hanna, Cowan, Tim, Henley, Benjamin J., Ribbe, Joachim, Freund, Mandy and Power, Scott. 2023. "Variability and long-term change in Australian monsoon rainfall: A review ." Wiley Interdisciplinary Reviews: WIREs Climate Change. 14 (3). https://doi.org/10.1002/wcc.823Test

الإتاحة: https://doi.org/10.1002/wcc.823Test
https://research.usq.edu.au/item/ww9zy/variability-and-long-term-change-inTest-australian-monsoon-rainfall-a-review
https://research.usq.edu.au/download/066bd294a4370f41373511346fdaf87c049d3f717c9d8dfca64451e653f00294/8249233/WIREs%20Climate%20Change%20-%202023%20-%20Heidemann.pdfTest

المؤلفون: Liang, Mingqiang, Zhang, jian, Li, Ting-Yong, Chen, Chao-Jun, Li, Jun-Yun

المساهمون: UCL - SST/ELI/ELIC - Earth & Climate

المصدر: Asian-Australian monsoon evolution over the last millennium linked to ENSO in composite stalagmite δ18O records, Vol. 281, no.1, p. 107420 (2022)

مصطلحات موضوعية: The past millennium, Asian-Australian monsoon, Stalagmite d18O, Integrated research, ENSO

الوصف: The Asian-Australian monsoon (AAM) system distinctly influences global climate. However, the linkage between ENSO (El Ni~noeSouthern Oscillation) and AAM is still poorly understood over the last millennium. Here, we combined stalagmite d18O (d18Os) records with exceptionally high-resolution and high-precision chronologies to demonstrate a tight remote coupling between AAM and tropical ocean hydrology on the multi-year, decadal, and centennial timescales. Our results reveal that (1) There is a significant negative correlation between the multi-year weighted average precipitation d18O (d18Oaw) from the AAM and Southern Oscillation Index (SOI), providing a modern analogous coupling for linking stalagmite d18O (d18Os) and ENSO over the past 100 years. (2) Over the last millennium, the integrated d18Os record exhibit positive excursions during the Little Ice Age (LIA), marked by a tendency for more El Ni~no-like state conditions in the tropical Pacific, which is consistent in SST-gradient ENSO reconstruction but different to precipitation reconstruction. (3) Wavelet and power spectrum analysis for the integrated d18Os record in the AAM region show that there is a significant multi-year periodicity (2.2, 2.8, 3.5, 4.6 yr), conceding with the ENSO cycle (2e7 yr), whereas, some multi-decadal and centennial cycles (10.1, 17, 28.6, 52.7, 143 yr) are significant too. We provide evidence from instrumental and paleocliamte datasets (GNIP and NOAA) and propose a possible “circulation effect†mechanism responsible for variations of d18Os in the East Asian Monsoon (EAM) and Australian Monsoon (AM) region over the last millennium

العلاقة: info:eu-repo/grantAgreement/National Natural Science Foundation of China/c13/No. 42172204; boreal:268999; http://hdl.handle.net/2078/268999Test; urn:ISSN:0277-3791; urn:EISSN:1873-457X

الإتاحة: http://hdl.handle.net/2078/268999Test

المؤلفون: Jieyu Liu, Shaobo Qiao, Chao Li, Shankai Tang, Dong Chen, Guolin Feng

المصدر: Atmospheric Science Letters, Vol 22, Iss 8, Pp n/a-n/a (2021)

مصطلحات موضوعية: Asian‐Australian monsoon region, climate warming, extreme precipitation, quantile regression, Meteorology. Climatology, QC851-999

الوصف: Abstract The Asian‐Australian monsoon (AAM) region is characterized as abundant summer monsoon rainfall, which provides fresh water resources for high‐density population there. The research uses HadGEM3‐A‐N216 model simulations to compare the change of extreme rainfall intensity in the AAM region with and without anthropogenic influences. Although the anthropogenic forcing exerts a weak impact on the climatological mean distribution of the extreme precipitation, it significantly increases the extreme precipitation intensity at each degree in most parts of the AAM region, especially for the northern East Asia, the Bay of Bengal, and Australia. As the extreme degree increases from the 50–98%, the extreme precipitation intensity in the northern East Asia, the Bay of Bengal, and the Australia increase more and more rapidly, while that in the southern East Asia changes from a decreasing trend to an increasing trend. Overall, the stronger extreme precipitation is accompanied by a stronger growth trend under the anthropogenic forcing.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/1530-261XTest

الوصول الحر: https://doaj.org/article/d140a3d2cceb42d8a123a34ef9730ab5Test

المؤلفون: Pei, Renjie, Kuhnt, Wolfgang, Holbourn, Ann, Jöhnck, Janika, Hingst, Johanna, Beil, Sebastian, Lübbers, Julia, Andersen, Nils, 1 Institute of Geosciences Christian‐Albrechts‐University Kiel Germany, 3 Laboratory for Radiometric Dating and Stable Isotope Research Christian‐Albrechts‐University Kiel Germany

مصطلحات موضوعية: ddc:551.46, Australian monsoon, Mg/Ca paleothermometry, SST, IODP, IPWP, SSS

الوصف: We collected a suite of core top samples during R/V Sonne Cruise SO257 in May 2017 along the southwestern front of the Indo‐Pacific Warm Pool (IPWP) to monitor the variability of Southern Hemisphere tropical and subtropical sea surface hydrology and to assess temperature and salinity reconstructions with data sets reflecting conditions in the post‐monsoonal season. In our core top samples, a steep increase in planktic δ18O, associated with a decrease in sea surface temperature (SST), indicates that the southwestern front of the IPWP is located between 23° and 24°S during austral fall. We additionally reconstructed SST, sea surface salinity ,and δ18O seawater (δ18Osw) over the last 450 kyr in two sediment successions located within and beyond the monsoonal rain belt. Our records show that SST was highly coherent and phase‐locked with atmospheric pCO2 during the last 450 kyr. The regional differences in the δ18Osw records reveal that the Western Australian Margin north of 15°S remained seasonally under the influence of IPWP water masses, even during glacials. The temporal variability in upper ocean hydrology along the Western Australian Margin is not directly coupled to local monsoonal precipitation, but is strongly affected by advective mixing of Indonesian Throughflow derived water masses. ; Key Points: Southwest front of modern Indo‐Pacific Warm Pool (IPWP) during austral fall is located between 23° and 24°S. Western Australian Margin north of 15°S remained seasonally influenced by IPWP throughout past 450 kyr. Upper ocean hydrology off Western Australia represents an integrated signal of monsoonal precipitation and advective mixing. ; China Scholarship Council ; German Federal Ministry of Education and Research

العلاقة: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/9765Test

الإتاحة: https://doi.org/10.1029/2021PA004222Test
http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/9765Test