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<jats:title>Abstract</jats:title><jats:p>Due to their potential role in organizing tropical mesoscale convective systems, a better understanding of cold pool (CP) dynamics in such regions is critical, particularly over land where the diurnal cycle further concentrates convective activity. Numerical models help disentangle the processes involved but often lack observational benchmarks. To close this gap, we analyze nearly 43 years of five‐minute resolution near‐surface timeseries, recorded from 12 automatic weather stations across equatorial Africa during 2019–2023. We identify 4,218 CPs based on criteria for temperature and wind. The identified CP gust fronts, which exhibit respective median temperature and specific humidity decreases of 5.3 K and 2.8 g kg<jats:sup>−1</jats:sup>, closely correlate with satellite‐observed brightness temperature discontinuities. Despite weak diurnal variation in precipitation, observed CP occurrence shows a pronounced diurnal cycle with an afternoon peak — a feature we attribute to low‐level moisture conditions. Our findings can serve as observational benchmark to improve simulations of CP organization.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The phenomenon of differential rotation of the Earth's inner core relative to the mantle is a subject of interest in geodynamo modeling that has been validated by seismological observations, mainly via the earthquake‐doublets method. Although recent studies converge on the time‐varying differential rotation of the inner core relative to the mantle, favoring a decadal variation, the inferred models significantly differ. Here, considering the data selection, the observed data structure, and the subjective model parameterizations, which we avoid by employing a Bayesian transdimensional approach, we show that the recent best‐fit model by Yang and Song (2023, <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://doi.org/10.1038/s41561-022-01112-z">https://doi.org/10.1038/s41561‐022‐01112‐z</jats:ext-link>) featuring the 70‐year decadal variation is not obtained when all available data are considered. Namely, including only a small number of discarded earthquake doublets (&lt;10%) changes the period of the inner‐core differential rotation fluctuation to 20–30 years. More earthquake‐doublet data are required to address the non‐uniqueness of the inversion problem.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Sap flow offers key insights about transpiration dynamics and forest‐climate interactions. Accurately simulating sap flow remains challenging due to measurement uncertainties and interactions between global and local environmental controls. Addressing these complexities, this study leveraged Long Short‐Term Memory networks (LSTMs) with SAPFLUXNET to predict hourly tree‐level sap flow across Europe. We built models with diverse training sets to assess performance under previously unseen conditions. The average Kling‐Gupta Efficiency was 0.77 for models trained on 50% of time series across all forest stands, and 0.52 for models trained on 50% of the forest stands. Continental models not only matched but surpassed the performance of specialized and baselines for all genera and forest types, showcasing the capacity of LSTMs to effectively generalize across tree genera, climates, and forest ecosystems given minimal inputs. This study underscores the potential of LSTMs in generalizing state‐dependent ecohydrological processes and bridging tree level measurements to continental scales.</jats:p>

<jats:title>Abstract</jats:title><jats:p>We reassessed several orbital topographic data sets for the Perseverance rover landing site at Jezero Crater, Mars to better understand its floor units. Tens‐of‐meters deep topographic anomalies occur in the volcanic floor of Jezero crater and are not a result of impact cratering. Eight km‐scale steep escarpment‐bounded depressions may be locations of paleotopographic highs that were embayed by the volcanic floor lava flows, forming inverted topography from either contemporaneous upward inflation of embaying lavas or later deep scour due to differential erosion over 10<jats:sup>7−9</jats:sup> years. Five multi km‐scale shallow‐sloped depressions linked by channel‐like forms may record locations of buried paleolakes and channels that predate the volcanic floor units or a drained magma system. These results indicate Jezero experienced multiple closed‐basin or dry phases, allowing erosion of the crater floor and creation of topography, which provides new geologic context for the samples gathered by Perseverance.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Intrashell oxygen isotope (δ<jats:sup>18</jats:sup>O<jats:sub>s</jats:sub>) analyses of terrestrial snails have been carried out over two decades. However, the intraspecies/interspecies differences are not yet well understood. Here, we conducted a high‐resolution intrashell δ<jats:sup>18</jats:sup>O<jats:sub>s</jats:sub> study on 43 shells from <jats:italic>Cathaica fasciola</jats:italic> and <jats:italic>Bradybaena ravida</jats:italic>, and 1449 δ<jats:sup>18</jats:sup>O<jats:sub>s</jats:sub> data were obtained. These large amounts of data demonstrate the reproducibility of intrashell δ<jats:sup>18</jats:sup>O<jats:sub>s</jats:sub>. Our results suggest that <jats:italic>C</jats:italic>. <jats:italic>fasciola</jats:italic> and <jats:italic>B</jats:italic>. <jats:italic>ravida</jats:italic> have similar growing seasons mainly from March to October in the studied region. The ecological habits of the two species could explain the distinctive variations in their δ<jats:sup>18</jats:sup>O<jats:sub>s</jats:sub> sequences. Therefore, our study may interpret the discrepancy between the studies of land snail species and the stable/clumped isotopes of their shells. Moreover, the calculated average growth rate is ∼290 μm/day (from 250 to 330 μm/day) for nonadult <jats:italic>C</jats:italic>. <jats:italic>fasciola</jats:italic>. Thus, the use of snail shells for reconstructing high‐resolution terrestrial climate changes is promising.</jats:p>

<jats:title>Abstract</jats:title><jats:p>A realistic representation of top‐of‐the‐atmosphere (TOA) radiation response to surface warming is key for trusting climate model projections. We show that coupled models with freely evolving ocean‐atmosphere interactions systematically underestimate the observed global TOA radiation trend during 2001–2022 in 552 simulations. Locally, even if a simulation spontaneously reproduces observed surface temperature trends, TOA radiation trends are more likely under‐ than overestimated. This response bias stems from the models' inability to reproduce the observed large‐scale surface warming pattern and from errors in the atmospheric physics affecting short‐ and longwave radiation. Models with a better representation of the TOA radiation response to local surface warming have a relatively low equilibrium climate sensitivity. Our bias metric is a novel process‐based approach which links a model's current response to climate change to its behavior in the future.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Jupiter's equatorial eastward zonal flows reach wind velocities of ∼100 m s<jats:sup>−1</jats:sup>, while on Saturn they are three times as strong and extend about twice as wide in latitude, despite the two planets being overall dynamically similar. Recent gravity measurements obtained by the Juno and Cassini spacecraft uncovered that the depth of zonal flows on Saturn is about three times greater than on Jupiter. Here we show, using 3D deep convection simulations, that the atmospheric depth is the determining factor controlling both the strength and latitudinal extent of the equatorial zonal flows, consistent with the measurements for both planets. We show that the atmospheric depth is proportional to the convectively driven eddy momentum flux, which controls the strength of the zonal flows. These results provide a mechanistic explanation for the observed differences in the equatorial regions of Jupiter and Saturn, and offer new understandings about the dynamics of gas giants beyond the Solar System.</jats:p>

<jats:p>No abstract is available for this article.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Wildfires are increasing across the USA. While smoke events affect human exposure and air quality, wildfire smoke effects on ecosystem‐atmosphere interactions are poorly understood. We investigate smoke effects on biogenic volatile organic compound (VOC) emissions and photosynthesis for ponderosa pines. During several wildfire smoke events, we observed photosynthetic reduction with evidence for stomatal plugging and changes in leaf‐level uptake and emission of both biogenic and wildfire VOCs. During intense smoke events, photosynthesis and VOC emissions were almost entirely suppressed, but increased dramatically upon stomatal opening. We propose four types of VOC responses to this burst in stomatal opening: post‐burst emissions, pulsed emissions, surge emissions, and post‐burst uptake. Our observations suggest that wildfire smoke can affect plant physiology and leaf‐atmosphere gas exchange.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Submesoscale vertical velocities, <jats:italic>w,</jats:italic> are important for the oceanic transport of heat and biogeochemical properties, but observing <jats:italic>w</jats:italic> is challenging. New remote sensing technologies of horizontal surface velocity at <jats:italic>O</jats:italic>(1) km resolution can resolve surface submesoscale dynamics and offer promise for diagnosing <jats:italic>w</jats:italic> subsurface. Using machine learning models, we examine relationships between the three‐dimensional <jats:italic>w</jats:italic> field and remotely observable surface variables such as horizontal velocity, density, and their horizontal gradients. We evaluate the machine learning models' sensitivities to different inputs, spatial resolution of surface fields, the addition of noise, and information about the subsurface density. We find that surface data is sufficient for reconstructing <jats:italic>w</jats:italic>, and having high resolution horizontal velocities with minimal errors is crucial for accurate <jats:italic>w</jats:italic> predictions. This highlights the importance of finer scale surface velocity measurements and suggests that data‐driven methods may be effective tools for linking surface observations with vertical velocity and transport subsurface.</jats:p>