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Abstract The Surface Water and Ocean Topography (SWOT) mission provides a good opportunity to study fine‐scale processes in the global ocean but whether it can detect balanced submesoscale eddies is uncertain due to the “contamination” by unbalanced inertial gravity waves. Here, based on concurrent observations from SWOT and a mooring array in the northwestern Pacific, we successfully captured two submesoscale cyclonic eddies with negative sea level anomalies (SLAs) in spring 2023. We find that the SLA amplitude and equivalent radius of the first (second) eddy are 2.5 cm and 16.0 km (2.0 cm and 18.8 km), respectively. For both eddies, their vertical scales are around 150 m and their horizontal velocities and Rossby numbers exceed 15.0 cm/s and 0.4, respectively. Further analysis suggests that similar submesoscale eddies can commonly occur in the northwestern Pacific and that SWOT is capable to detect larger submesoscale eddies with scales greater than ∼10 km.

Abstract Introduction This study aimed to validate the effectiveness, safety and feasibility of water‐filtered infrared A radiation (WIRA) whole‐body hyperthermia combined with immune checkpoint inhibitor (ICI) therapy (HIT) and evaluate the real‐world clinical application prospects. Methods This open‐label single‐arm phase 2 clinical trial (NCT06022692) aimed to enrol advanced gastrointestinal tumour (GIT) patients with the MSS/pMMR phenotype. The patients were treated with whole‐body hyperthermia on Days 1 and 8 of each HIT cycle along with administration of tislelizumab on Day 2. Results Between 1 June 2020 and 31 May 2022, 18 patients were enrolled in the study, including those with gastric cancer (n = 6), colon cancer (n = 7), rectal cancer (n = 3) and appendiceal cancer (n = 2). As of 19 May 2023, 17 of the 18 patients had died, including 14 deaths caused by tumour progression and three deaths caused by diseases other than cancer, while one patient was still undergoing follow‐up. In terms of efficacy, the median DCR was 55.6%, while the median PFS and OS were 53.5 days and 134 days, respectively. Four patients (22.2%) experienced immune‐related adverse events, and none of the patients reported grade 3 or higher irAEs. Hyperthermia was followed by an increase in the number of tumour immune‐activated cells. Conclusions HIT can provide survival benefits in patients with GITs by activating antitumour immune function and shows good safety and feasibility.

Abstract The East China Sea Kuroshio (ECS‐Kuroshio) and the Ryukyu Current are the major poleward heat carriers in the North Pacific. Anomalous changes of ECS‐Kuroshio and Ryukyu Current could exert substantial influence on the climate in mid‐latitude regions. However, owing to limited observations and coarse resolution of climate models, how they might change under anthropogenic warming remains unknown. Here, we find an accelerating ECS‐Kuroshio (1.5 Sv) and a decelerating (−2.2 Sv) Ryukyu Current using in‐situ observation during 1958–2022, equivalent to 7% strengthening and 20% weakening in the 65 years. The trend is also simulated by four high‐resolution climate models, with multi‐model ensemble‐mean acceleration (deceleration) of the ECS‐Kuroshio (Ryukyu Current) of 1.2 ± 0.6 Sv (−6.2 ± 2.5 Sv) over 1950–2050. The weakening subtropical wind field reduces their summed transport o. Enhanced stratification, which induces uplift of current system and weaker topography‐flow interaction, leads to the intensifying ECS‐Kuroshio and disappearing Ryukyu Current.

Abstract Marine heatwaves (MHWs) are prolonged extreme warm water events, threatening marine ecosystems. Understanding drivers of MHWs over the global ocean is essential for their forecast. Here, we use an eddy‐resolving coupled global climate model with improved realism of MHWs to evaluate the drivers of MHWs at different spatial scales, that is, MHWs defined based on temperature anomalies at different spatial scales. The properties of MHWs are scale‐dependent, being generally weaker, less frequent, and longer with increasing spatial scales. The primary driver of MHWs shifts from local oceanic intrinsic advection to atmospheric forcing as their spatial scale becomes larger. The transition spatial scale between the ocean and atmosphere‐driven regimes varies geographically, being larger in eddy‐rich regions but smaller in gyre interior. This study suggests the complicated dynamics of MHWs at different spatial scales and provides guidance on improving their forecast capacity.

Abstract Air‐sea exchanges across oceanic fronts are critical in powering cloud formation, precipitation, and atmospheric storms. Oceanic submesoscale fronts of scales 1–10 km are characterized by strong sea surface temperature (SST) gradients. However, it remains elusive how submesoscale fronts affect the overlying atmosphere due to a lack of high‐resolution observations or models. Based on rare high‐resolution in situ observations in the Kuroshio Extension region, we quantify the air‐sea exchanges across an oceanic submesoscale front. The cross‐front SST and turbulent heat flux gradients reaches 2.4°C/km and 47 W/m2/km, respectively, far stronger than that typically found in mesoscale‐resolving products. The stronger SST gradient drives substantially stronger air‐sea fluxes and vertical mixing than mesoscale fronts, enhancing cloud formations. The intense air‐sea exchanges across submesoscale fronts are confirmed in idealized model simulations, but not resolved in mesoscale‐resolving climate models. Our finding provides essential knowledge for improving simulations of cloud formation, precipitation, and storms in climate models.

Abstract Ocean vertical velocity (w) plays a key role in regulating the exchanges of mass, heat and nutrients between the surface and deep ocean. However, direct observation remains difficult due to its small magnitude and large spatiotemporal variability. Therefore, w fields are generally diagnosed using dynamic‐based methods. In this study, we developed a deep neural network (DNN) to reconstruct three‐dimensional fields of ocean vertical velocity based on sea surface height (SSH) fields. Compared to dynamic‐based methods, the DNN shows improved performance in the w reconstruction within upper 500 m in terms of higher correlation and less error. Remarkably, the DNN requires only a ∼45 × 45 km size SSH image as input to estimate w at the center. This suggests that the DNN has great potential for w reconstruction in the future combined with high‐resolution observations such as the Surface Water and Ocean Topography mission.

Abstract Oceanic lee waves play an important role in dissipating wind‐driven ocean circulations and powering turbulent diapycnal mixing. Here we investigate impacts of the greenhouse warming on global energy conversion into lee waves using a linear theory of lee wave generation and output from a high‐resolution (0.1° for the ocean) coupled global climate model. The global energy conversion rate into lee waves under the historical (1930s) climate condition is estimated to be 193.0 ± 3.0 GW. Under the high carbon emission scenario, this conversion rate is projected to decrease by about 20% by the end of 21st century, due to weakened bottom large‐scale mean flows, mesoscale eddies and stratification. The decrease of the conversion rate is widespread and particularly pronounced in the Gulf Stream and Drake Passage.

Abstract The response of upwelling in the eastern boundary upwelling systems (EBUSs) to anthropogenic climate change has attracted much scientific attention due to its core role in nourishing marine ecosystems. A decade‐old hypothesis suggests that greenhouse warming may intensify upwelling‐favorable winds and subsequently the upwelling in EBUSs, but the impact of greenhouse warming on the seasonal cycle of upwelling remains unknown. Using the recent generation of global climate simulations under a high carbon emission scenario, we show a universal weakening of the upwelling seasonal cycle in the major EBUSs. This is mainly ascribed to the projected weakened seasonal cycle of the upwelling‐favorable winds. In addition, long‐term changes in geostrophic transport exert a nonnegligible contribution to the changes in the upwelling seasonal cycle. Our study suggests that the upwelling in the EBUSs is likely to have a more complicated response to greenhouse warming than previously thought.

Abstract El Niño/Southern Oscillation (ENSO) exhibits evident amplitude asymmetry with stronger El Niño than La Niña events. Equatorial submesoscale eddies act as an important damper of ENSO via their induced upward heat flux (Qeddy,vsub) from the subsurface to the surface ocean. Yet their effect on ENSO amplitude asymmetry remains unexplored. Using a high‐resolution global climate simulation, we found that strengthening of Qeddy,vsub in the Niño3.4 region during La Niña is more evident than weakening of Qeddy,vsub during El Niño, resulting in stronger damping of La Niña than El Niño events. This asymmetric response of Qeddy,vsub to ENSO is primarily ascribed to that of the temperature fronts associated with larger‐scale processes. Using a recharge oscillator model modified to include the effects of Qeddy,vsub, we show that the asymmetric damping of ENSO by Qeddy,vsub contributes importantly to the ENSO amplitude asymmetry.

Abstract Objective Tumor cells could acquire drug resistance through cell autophagy. This study aimed to explore the role of SNHG16 in sorafenib‐resistant HCC cells and its mechanism with miR‐23b‐3p. Methods The sorafenib‐resistant Hep3B cell model was established. The SNHG16 and miR‐23b‐3p gene expressions were determined in normal HCC and sorafenib‐resistant HCC tissues. Detection of the expression of SNHG16 and miR‐23b‐3p and its respective correlation with survival rate were performed. Target genes to SNHG16 and miR‐23b‐3p were predicted, and verified by dual‐fluorescent reporter assay. The effects of SNHG16 and miR‐23b‐3p on SNHG16, miR‐23b‐3p, EGR1 expression, viability, apoptosis as well as LC3II/LC3 expression in Hep3B and Hep3B/So cells were detected by qRT‐PCR, CCK‐8, flow cytometry, and western blot. In in vivo studies, the NOD/SCID mice model was established to explore the effects of Hep3B and Hep3B/So cells with inhibited SNHG16 or miR‐23b‐3p on tumor size, EGR1 expression, and autophagy. Results High SNHG16 expression in HCC‐resistant tissues and low miR‐23b‐3p expression in all HCC tissues were detected, and the two were negatively correlated. Low SNHG16 and high miR‐23b‐3p were related to a high survival rate of HCC patients. Moreover, SNHG16 overexpression promoted Hep3B/So cell viability and autophagy, suppressed apoptosis by inhibiting miR‐23b‐3p expression through up‐regulating EGR1, however, the effect of si‐SNHG16 was opposite. In in vivo studies, miR‐23b‐3p inhibitor suppressed the high sorafenib sensitivity in Hep3B/So cells caused by SNHG16 silencing through promoting viability, autophagy, and suppressing apoptosis. Conclusion SNHG16 promotes Hep3B/So cell viability, autophagy, and inhibits apoptosis to maintain its resistance to sorafenib through regulating the expression of miR‐23b‐3p via sponging EGR1.