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Marine heatwaves (MHWs) have adverse impacts on marine ecosystems and fisheries, yet extreme MHWs in the western tropical Pacific Ocean remain largely unexplored. Here, we investigate the evolution and drivers of the two strongest subsurface MHWs in the western tropical Pacific Ocean on record, in 2008 (MHW-08) and 2010–11 (MHW-11). The two events have similar evolutions, as they were both initiated and developed locally in tropical regions during their onset phase and gradually dissipated with multiple cores during the decay phase. We examined the physical processes during the evolution of MHW-08 and MHW-11 and performed a heat budget analysis for the subsurface layer in each case. We find that the onset of both events were mainly controlled by convergence and vertical heat advection due to anomalous Ekman downwelling, while the decay of both events was mainly controlled by horizontal heat advection due to anomalous horizontal currents and withdrawal of anomalous convergence. The relationship between the subsurface MHWs and El Niño–Southern Oscillation is discussed. We suggest that the anomalous heat advections plus the La Niña–related background warming lead to the extreme subsurface MHW events. Our findings may have important implications for environmental change and marine life in the western tropical Pacific Ocean. [ABSTRACT FROM AUTHOR]

While the pivotal role of the Indonesian Throughflow (ITF) in the global ocean circulation and climate has been widely recognized, accurate estimation of its volume transport based on observational data remains challenging. This work provides an updated estimate of the monthly ITF geostrophic transport (ITFG) in the upper 700 m at the IX1 section between Indonesia and Australia. The ITFG estimate is better constrained by improved data correction and new salinity data products. The mean ITFG of 1993–2018 is 8.2 ± 0.2 Sv, in which contributions of the temperature and salinity components (ITFT and ITFS) are 5.5 ± 0.2 and 2.8 ± 0.1 Sv, respectively. The interannual variability (∼4.4 Sv in standard deviation) is dominated by ITFT, as the result of wind‐driven thermocline dynamics, and slightly attenuated in amplitude by ITFS. The strengthening trend of 1.33 Sv decade−1 during 1993–2018 primarily arises from ITFS and secondarily from ITFT. Plain Language Summary: The Indonesian Throughflow (ITF) is of worldwide importance for the ocean circulation and climate. Existing estimates of the ITF's volume transport are subjected to uncertainties associated with data biases and simplified approaches. Here, we provide a more accurate estimate of the ITF geostrophic transport (ITFG) at the IX1 line, by adopting improved historical data correction and more realistically considering the ocean salinity effect. The IX1 line has the best and longest data coverage to represent the net transport of the upper‐layer throughflow. The mean ITFG of 0–700 m is 8.2 ± 0.2 Sv, wherein the contributions of temperature and salinity are 5.5 ± 0.2 and 2.8 ± 0.1 Sv, respectively. The ITFG variabilities on seasonal and interannual timescales are dominated by the temperature component, whereas most part of the increasing trend of 1.33 Sv decade−1 during 1993–2018 arises from the salinity component. Key Points: An updated estimate of the Indonesian Throughflow (ITF) is provided, with improvements in data correction, uncertainty estimation, and salinity effectThe ITF in the upper 700 m is of a mean geostrophic transport of 8.2 ± 0.2 Sv and interannual variability of ∼4.4 SvSalinity exerts a weak damping effect on ITF's interannual variability but fundamentally contributes to its strengthening trend since 1993 [ABSTRACT FROM AUTHOR]

Pacific Ocean western boundary currents and the interlinked equatorial Pacific circulation system were among the first currents of these types to be explored by pioneering oceanographers. The widely accepted but poorly quantified importance of these currents--in processes such as the El Niño/Southern Oscillation, the Pacific Decadal Oscillation and the Indonesian Throughflow--has triggered renewed interest. Ongoing efforts are seeking to understand the heat and mass balances of the equatorial Pacific, and possible changes associated with greenhouse-gas-induced climate change. Only a concerted international effort will close the observational, theoretical and technical gaps currently limiting a robust answer to these elusive questions., Author(s): Dunxin Hu [1]; Lixin Wu (corresponding author) [2]; Wenju Cai (corresponding author) [2, 3]; Alex Sen Gupta [4]; Alexandre Ganachaud [5]; Bo Qiu [6]; Arnold L. Gordon [7]; Xiaopei [...]

(D) Contrast-enhanced chest computed tomography scan showing an irregular and poorly defined mass (asterisk) in the right superior mediastina with deformation and partial occlusion of the superior vena cava. A 58-year-old woman was hospitalized in our rheumatology department with a 1-month history of myalgia, edema on bilateral hands and feet, and puffy face, without systemic symptoms such as fever, weight loss, or anorexia. Subsequent contrast-enhanced chest computed tomography scan showed an irregular and poorly defined mass (Figure 1D, asterisk) in the right superior mediastina with deformation and partial occlusion of the superior vena cava. [Extracted from the article]