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Polar stratospheric clouds (PSCs) play a crucial role in ozone depletion in the polar stratosphere. In this study, the space-based PSCs record from CALISPO and an offline three-dimensional chemical transport model (SLIMCAT) are used to analyze the PSCs in the Arctic and the Antarctic for the period 2006−2021. Observations indicate that the seasonal evolution of the Antarctic PSC area is similar from year to year. In contrast, the Arctic PSCs show large differences in seasonal variations of coverage and duration in different years. The SLIMCAT simulations effectively capture the seasonal and interannual variations of PSCs. However, the simulated PSC areas are larger than CALIPSO observations, which can be attributed to the relatively high instrumental detection threshold of CALIPSO. SLIMCAT can capture the zonal asymmetry of PSCs in both the Antarctic and Arctic, and it can reproduce a more accurate spatial distribution of PSCs when the PSC coverage area is larger. In addition, accurate simulation of HNO3 is important for PSC simulation. Because the simulation of denitrification processes is poor in SLIMCAT, which uses the thermodynamic equilibrium PSC scheme, the PSCs modeled by SLIMCAT are located at higher altitudes compared to the observation in the Antarctic, where the denitrification processes are strong. In contrast, for ice PSCs of which HNO3 is not required in calculations and the Arctic where denitrification is weak, the simulated PSC at different altitudes closely matches the observations. [ABSTRACT FROM AUTHOR]

Based on multi‐model large‐ensemble experiments provided by Polar Amplification Model Intercomparison Project (PAMIP), we investigate the influence of the projected sea ice loss in Barents‐Kara Seas (BKS) and Sea of Okhotsk (SOK) on the Arctic stratospheric polar vortex (SPV). Results show that future BKS sea ice reduction leads to a weakened SPV during November‐February by enhancing the upward‐propagating planetary wave 1, which is more pronounced during Quasi‐Biennial Oscillation (QBO) easterly than westerly phase. Through weakening the upward‐propagating planetary wave 2, future SOK sea ice reduction is favorable for a strengthened SPV during January‐April. Inter‐model spread in the magnitudes of SPV responses to BKS sea ice reduction can be largely explained by the divergent planetary wave responses, but less so for SOK sea ice reduction. Results from a linearized baroclinic model further validate the importance of the planetary‐scale wave responses in explaining the differing SPV responses to sea‐ice loss over the two regions. Plain Language Summary: Arctic sea ice reduction influences the Northern Hemispheric weather and climate through modulating Arctic stratospheric polar vortex, which is a band of strong westerly encircling the pole during winter at ∼15–40 km above the Earth's surface. However, sea ice reduction over different regions could lead to different effects on the polar vortex. Here, we compare the effects of future sea ice reduction over the Barents‐Kara Seas, in the far‐north Atlantic Ocean, and the Sea of Okhotsk, in the northwest Pacific Ocean. We use carefully designed numerical simulations to estimate the effects of sea ice reduction, separately in the above‐mentioned two regions, on the polar vortex. Sea ice reduction over the Barents‐Kara Seas weakens the polar vortex, whereas sea ice reduction over Sea of Okhotsk strengthens the polar vortex. These contrasting effects are explained by opposing changes in wave activity entering the stratosphere from below. Barents‐Kara sea ice reduction leads to the strengthened upward propagating planetary waves, which break in the stratosphere and slow the polar vortex. Conversely, Okhotsk sea ice loss reduces upward waves and strengthens the polar vortex. Key Points: Barents‐Kara and Sea of Okhotsk sea ice loss weakens and strengthens polar vortex, respectively, with attendant changes in SSW frequencyPlanetary wave responses to Barents‐Kara and Okhotsk sea ice loss interfere constructively and destructively with mean flow, respectivelyPolar vortex weakening induced by Barents‐Kara sea ice loss is greater during easterly than westerly Quasi‐Biennial Oscillation phase [ABSTRACT FROM AUTHOR]

Using observations and CMIP6 historical simulations, the seasonal responses of Southern Ocean (50°S–70°S) sea surface temperature (SST) to Southern Annular Mode (SAM) variations are investigated in this study. The results suggest that the averaged Southern Ocean SST in austral spring and summer show a significant cooling in response to a positive SAM, while the responses in austral autumn and winter are negligible. The cooling effect is resulted from the cold water in higher latitudes and deeper oceans brought by the equatorward Ekman transport and the Ekman pumping associated with the positive SAM. Among CMIP6 models, the magnitude of the simulated cooling response connects to the climatological meridional and vertical ocean temperature gradients, and the magnitude of Ekman motion in response to SAM. In addition, the spring and summer SAM plays a more important role in modulating Southern Ocean SST in autumn and winter than the autumn and winter SAM. Plain Language Summary: Southern Annular Mode (SAM) is the first leading mode of atmospheric circulation in extratropical Southern Hemisphere and has an important influence on climate. This study evaluates the seasonal response of Southern Ocean SST to SAM variations in the CMIP6 historical simulations. We found that the regional averaged Southern Ocean sea surface temperature (SST) in austral spring and summer shows significant cooling signals in response to positive SAM. The responses of mean SST over Southern Ocean in austral autumn and winter to SAM during same seasons are not significant. The strengthening in Ekman transport and Ekman pumping in response to positive SAM would bring cold water from higher latitudes and deeper ocean to ocean surface, and hence, lead to a cooling effect. In addition, the simulations with a larger climatological meridional or vertical temperature gradient and stronger Ekman movements in response to positive SAM tends to generate a stronger cooling signal over Southern Ocean driven by positive SAM. Further analysis indicates that the austral spring and summer SAM has a more significant impact on Southern Ocean SST in austral autumn and winter, which might explain why the responses of Southern Ocean SST in austral autumn and winter to simultaneous SAM are not statistically significant. Key Points: The Southern Ocean sea surface temperature (SST) show a significant cooling in response to positive Southern Annular Mode (SAM) in austral spring and summerThe Ekman movements associated with enhanced SAM bring cold water from higher latitudes and deeper ocean, causing cooling effectsSAM in spring and summer play a more important role in modulating the autumn and winter SST than the SAM in autumn and winter [ABSTRACT FROM AUTHOR]

The interface of perovskite solar cells (PSCs) plays an important role in transferring and collecting charges. Interface defects are important factors affecting the efficiency and stability of PSCs. Here, the buried interface between SnO2 and the perovskite layer is bridged by two‐dimensional (2D) MBene, which improves charge transfer. MBene can deposit additional electrons on the surface of SnO2, passivate its surface defects and facilitate the charge collection. Moreover, the dipole moment formed at the interface increases the electron transfer ability in the PSCs. MBene also regulates the growth of perovskite crystals, improves the quality of perovskite films, and reduces its grain boundary defects. As a result, PSCs based on FA0.2MA0.8PbI3 and (FAPbI3)0.95(MAPbBr3)0.05 get the enhanced efficiencies of 22.34 % and 24.32 % with negligible hysteresis. Furthermore, the optimized device exhibits better stability. This work opens up the application of MBene materials in PSCs, reveals a deeper understanding of the mechanism behind using 2D materials as an interface modification layer, and shows opportunities for using MBene as potential material in photoelectric devices. [ABSTRACT FROM AUTHOR]

Climate change represents a profound threat to the diversity and stability of global climate zones. However, the complex interplay between climate change and elevation in shaping climate heterogeneity is not yet fully understood. Here, we combine Shannon's diversity index (SHDI) with the Köppen‐Geiger climate classification to explore the altitudinal distributions of global climate heterogeneity; and their responses to climate change. The study reveals a distinctive pattern: SHDI, a proxy for climate heterogeneity tends to slow down or decline at lower elevations with increasing temperatures, while at higher elevations, it continues to rise due to continuing cold conditions. Examination of climate simulations, both with and without anthropogenic forcing, confirms that observed changes in climate heterogeneity are primarily attributable to anthropogenic climate change within these high‐elevation regions. This study underscores the importance of high‐elevation regions as not only custodians of diverse climate types but also potential refuges for species fleeing warmer climates. Plain Language Summary: Climate change is threatening the diversity and stability of global climate patterns. But we're still not completely sure how climate change interacts with elevation to affect climate heterogeneity. In this study, we looked at how climate heterogeneity changes with altitude and responds to climate change. We found that as temperatures rise, the climate diversity tends to decrease at lower elevations, but it increases at higher elevations. We used climate simulations to show that these changes can be attributed to anthropogenic climate change. This study shows that high‐elevation regions are important because they can sustain diverse climates and are likely to be a safe haven for plants and animals when climate diversity continues to decline at lower elevations. Key Points: We employed a high‐resolution climate data set to analyze changes in global climate heterogeneityWith increasing temperatures, global climate heterogeneity amplifies at higher elevations, while diminishing at lower altitudesAnthropogenic climate change primarily drives alterations in climate heterogeneity at higher elevations [ABSTRACT FROM AUTHOR]

The paint remover containing benzyl alcohol and hydrogen peroxide is safe and environmental friendly. To improve the paint removing efficiency, it is necessary to increase the amount of hydrogen peroxide. However, it might cause the corrosion of titanium alloys. The effects of different hydrogen peroxide content (e.g., 4.5%, 9%, 13.5% and 18%), different pH values (e.g., 5.0, 6.0, 7.0, 8.0 and 9.0), different hydrogen peroxide decomposition inhibitors (e.g., polyacrylamide, magnesium stearate, sodium tripolyphosphate and EDTA-Na2), and different corrosion inhibitor formulations (e.g., EP030, benzotriazole, IDS magnesium and CTAB) are tested.The results show that the corrosion of titanium alloy is minimum and the paint removing efficiency meet the requirements when the amount of hydrogen peroxide is 3%, the pH of the paint remover is 5-6 and the ratio of A and B agents is 1:1. [ABSTRACT FROM AUTHOR]