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Large‐scale volcanic eruptions, such as the Hunga‐Tonga volcanic eruption that occurred in 2022, can impact the atmospheric structure and dynamics in a highly complex way. The response of Nitric oxide (NO) radiative emissions to the lower atmospheric forcing caused by the Hunga‐Tonga eruption has been examined in this study using Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) measurements. On 15 January, neutral densities and NOIRF (Nitric Oxide Infrared Radiative Flux) were found to be depleted over the Hunga‐Tonga following the volcanic eruption, as observed by Swarm and SABER. Subsequently, the following day, a significant and highly localized enhancement in NOIRF is observed. Using TIEGCM (Thermosphere Ionosphere Electrodynamics General Circulation Model) simulations with gravity wave input, it has been established that wave‐induced lower atmospheric forcing is primarily responsible for the compositional and temperature changes. These changes influence the vibrational excitation mechanism of NO, resulting in the observed emission pattern during the Hunga‐Tonga event.

Accurate quantification of terrestrial carbon dynamics is essential for assessing ecosystem–climate feedbacks and informing climate mitigation in the Anthropocene. China, as both the world’s largest emitter and a region of rapid ecological change, plays a key role in the global carbon cycle. Yet uncertainties in atmospheric forcing datasets remain a significant source of uncertainty in land surface model simulations and are rarely assessed systematically. Here, we assess China’s terrestrial carbon budget (1979–2014) using the Community Land Model (CLM5.0) driven by three widely used meteorological datasets: CRUNCEP, the Global Soil Wetness Project Phase 3 (GSWP3), and the China Meteorological Forcing Dataset (CMFD), and evaluated against more than 800 FLUXNET site-months and nine eddy covariance towers. Forcing choice strongly alters the magnitude and trend of carbon fluxes, and China’s terrestrial ecosystems acted as either a weak carbon sink or a net source, depending on the forcing. GSWP3 performed best overall in simulating gross primary productivity (GPP), CRUNCEP relatively poorly, and CMFD best in high-altitude and cold-dry regions. Total ecosystem carbon storage was estimated at 86.30–90.00 PgC, primarily in soil (84.1%) and vegetation (15.9%). Interannual GPP variability was mainly controlled by precipitation (29.4%), followed by temperature (17.2%), while shortwave radiation had negative effects (11.5%). Shapley additive explanations analysis further showed that moisture-related variables (precipitation and humidity) dominate interannual GPP variability. By combining process-based modeling and machine learning, this study shows how uncertainties in meteorological inputs affect terrestrial carbon dynamics. These findings underscore the limitations of single-forcing simulations in Earth system modeling and highlight the need for improved meteorological inputs to support robust carbon budgeting and climate neutrality goals.

Proudman resonance is a primary amplification mechanism for meteotsunamis, which are shallow-water waves generated by atmospheric forcings. The effect of tides, sloping bathymetry and the speed, amplitude and aspect ratio of the atmospheric forcing on Proudman resonant wave growth are investigated using analytical approximations and numerical models. With tides included, maximum wave growth through Proudman resonance occurred when the atmospheric-forcing speed matched the tidal-wave speed. Growth greater than Proudman resonance occurred with a positive tidal elevation together with a tidal current in the opposite direction to wave propagation, due to linear growth combined with further amplification from wave-flux conservation. Near-Proudman resonant growth occurred when the forced-wave speed or free-wave speed varied by either a small amount, or varied rapidly, around a speed appropriate for Proudman resonance. For a forcing moving at Proudman resonant speed, resultant wave growth was proportional to the total, time-integrated forcing amplitude. Finally, Proudman resonant wave growth was lower for forcings with lower aspect ratios (AP), partly because forced-wave heights are proportional to 1 + AP2, but also because free waves could spread in two dimensions. Whilst the assumptions of strict Proudman resonance are never met, near-Proudman resonant growth may occur over hundreds of kilometres if the effective Froude number is near 1 and the resultant wave propagates predominantly in one dimension.

Global estimates of the land carbon sink are often based on simulations by terrestrial biosphere models (TBMs). The use of a large number of models that differ in their underlying hypotheses, structure and parameters is one way to assess the uncertainty in the historical land carbon sink. Here we show that the atmospheric forcing datasets used to drive these TBMs represent a significant source of uncertainty that is currently not systematically accounted for in land carbon cycle evaluations. We present results from three TBMs each forced with three different historical atmospheric forcing reconstructions over the period 1850–2015. We perform an analysis of variance to quantify the relative uncertainty in carbon fluxes arising from the models themselves, atmospheric forcing, and model-forcing interactions. We find that atmospheric forcing in this set of simulations plays a dominant role on uncertainties in global gross primary productivity (GPP) (75% of variability) and autotrophic respiration (90%), and a significant but reduced role on net primary productivity and heterotrophic respiration (30%). Atmospheric forcing is the dominant driver (52%) of variability for the net ecosystem exchange flux, defined as the difference between GPP and respiration (both autotrophic and heterotrophic respiration). In contrast, for wildfire-driven carbon emissions model uncertainties dominate and, as a result, model uncertainties dominate for net ecosystem productivity. At regional scales, the contribution of atmospheric forcing to uncertainty shows a very heterogeneous pattern and is smaller on average than at the global scale. We find that this difference in the relative importance of forcing uncertainty between global and regional scales is related to large differences in regional model flux estimates, which partially offset each other when integrated globally, while the flux differences driven by forcing are mainly consistent across the world and therefore add up to a larger fractional contribution to global uncertainty.

Amid growing attention to climate change, most coastal oceanographic studies have focused on long-term trends, with comparatively less emphasis on the impacts of short-lived synoptic weather systems, such as cold fronts, on coastal water quality. These transient events can drive rapid shifts in biogeochemical processes with significant ecological consequences. This study investigated the short-term variability of water quality parameters in the Louisiana Continental Shelf in response to wind-driven changes in coastal currents following a cold front. A vessel-based survey conducted in March 2021 involved repeated high-frequency sampling along a 30 km transect over a 36-hour period. Measurements included salinity, temperature, chlorophyll- a (chl- a ), pH, dissolved oxygen (DO), colored dissolved organic matter (CDOM), and turbidity from CTD casts; concentrations of dissolved organic carbon (DOC), nitrate (NO 3 − ), nitrite (NO 2 − ), ammonium (NH₄⁺), and phosphate (PO₄³⁻) from discrete water samples; and continuous velocity profiles from an onboard acoustic Doppler current profiler (ADCP). Results showed pronounced increases in salinity and temperature gradients following the cold front, accompanied by more than a threefold change in coastal current velocities associated with a transiting high-pressure system. Westward DOC transport peaked at 132 kg/s, equivalent to approximately 11,379 metric tons per day. Southward transport reached 68.7 kg/s, or roughly 5,940 metric tons per day, indicating significant along- and cross-shelf carbon transport. NH₄⁺ transport reached a maximum of 18.3 kg/s, while NO₃⁻ transport peaked at 18 kg/s, both reflecting strong nutrient pulses. Westward chl- a transport was highest at 0.554 kg/s during the first pass along the transect and declined thereafter, mirroring post-frontal shifts in primary productivity. CDOM transport decreased from 0.0386 kg/s to 0.0177 kg/s over the course of the survey, suggesting offshore dilution and mixing. These findings highlight the substantial influence of short-term atmospheric forcing on biogeochemical fluxes, revealing how compound hydrometeorological events, characterized by abrupt wind shifts, thermal gradients, and freshwater inputs, can drive rapid and nonlinear changes in coastal water quality. The results demonstrate the tight coupling between meteorological dynamics and near-shore biogeochemical processes on the LCS, and, when considered alongside evidence from other river-influenced coastal systems worldwide, underscore the broader global relevance of transient atmospheric events in shaping coastal circulation, nutrient transport, and ecosystem variability.

The recent major production of anomalously warm, salty deep water in the northwestern Mediterranean Sea (winters 2004–2005 and 2005–2006) is linked to extreme winter air‐sea heat and freshwater forcing of the basin. Fields of heat and density fluxes are determined both from the National Centers for Environmental Prediction‐National Center for Atmospheric Research reanalysis and a daily high‐resolution downscaling of the European Centre for Medium‐Range Weather Forecasts reanalysis and analysis data set ARPERA. In the deep water formation region, during winter 2004–2005, the net heat loss exceeds 300 W m−2 compared with typical values of 200 W m−2. The relationship between the deep water formation episodes and large‐scale atmospheric patterns is investigated and found to be more closely related to the East Atlantic Pattern than the North Atlantic Oscillation. The contributions of atmospheric forcing and lateral advection of anomalously warm, salty water to the convection region are discussed in order to determine their relative roles in causing massive renewal of Western Mediterranean Deep Water and its anomalous properties. The main result shows that the net evaporation during winter 2004–2005, even if very high compared to the climatology, could have induced only 49% of the actual observed increase in the salt content of the deep layer. Thus, lateral advection played a major role in setting the new deep water properties.

The generation and propagation of meteorological tsunamis (meteotsunamis) were numerically investigated in coastal waters of Buenos Aires Province. This study was carried out using a vertically integrated ocean model driven by a theoretical atmospheric forcing. This forcing simulates a train of nondispersive atmospheric gravity waves (AGW) propagating within a bounded area that moves at the speed of the synoptic systems. Firstly, a study case of simultaneous AGW and meteotsunami activity was simulated to validate the implemented methodology. Subsequently, after several numerical experiments, it was obtained that the amplitude, the dominant period, and the direction of propagation of the AGW train were the parameters that have the largest impact on the simulated meteotsunami amplitude. Maximum meteotsunami wave height (0.85 m) was obtained at Punta Rasa (the northern extreme of the coast of Buenos Aires Province) when the AGW reached this location. Numerical outcomes also showed that the meteotsunamis would propagate like ocean edge waves. In these cases, the continuous transference of energy from the atmosphere to the ocean could be possible (Greenspan resonance). Even though the implemented theoretical forcing is realistic, the numerical experiments revealed that some particular issues should be enhanced to better simulate the genesis and propagation of the meteotsunamis in coastal waters of the Buenos Aires Province. These issues are analyzed and discussed in this paper.

Serrano, M.A.; Díez-Minguito, M.; Valle-Levinson, A., and Ortega-Sánchez, M., 2020. Circulation in a short, microtidal submarine canyon in the Alborán Sea. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 1531–1535. Coconut Creek (Florida), ISSN 0749-0208. This study analyzes the circulation of a short, microtidal submarine canyon from observations and an analytical model. The Jolúcar submarine canyon is located near the Carchuna beach (Granada, southern Spain) in the northern continental shelf of the Alborán Sea. Observations were analyzed with harmonic and spectral analyses techniques. Observations showed two layers flowing in opposite directions: down-canyon in the bottom layer and up-canyon in the upper layer. This suggest that the canyon might flush out dense materials form the nearshore. Moevoer, observed currents were mainly driven by tidal (10%) and, more significantly, by atmospheric forcing, i.e., by wind stress and local atmospheric pressure gradients, as shown by cross-spectral analysis. In order to explore the dynamics associated with these results, a classical analytical solution of wind-induced current profile in a non-homogeneous water column was extended to include the influence of pressure gradients. This result demonstrated that the circulation in Jolúcar canyon could be influenced by atmospheric pressure gradients.

Based on our previous study (Yu et al., Clim Dyn 49:1139–1156, 2017), this paper further investigates the interdecadal change in the relationship between the Kuroshio Extension (KE; 27°–37°N, 140°–158°E) and the East Asian summer monsoon (EASM) in the late 1980s. The summer KE sea surface temperature anomalies (SSTAs) show a significant positive relationship with the EASM over the period 1968–1987 (P1), but a significant negative connection with the EASM between 1991 and 2010 (P2). This interdecadal change in the KE–EASM relationship can be interpreted by considering the difference in the relationships of summer KE SSTAs with the East Asian subtropical westerly jet (EASWJ) and western North Pacific subtropical high (WNPSH) during the two periods. During P1, summertime KE SST warming is significantly related to the strengthened EASWJ and WNPSH, but it has close relationships with the weakened and northward-moving EASWJ and WNPSH during P2. These anomalous EASWJ and WNPSH associated with the summertime KE SST warming in P1 (P2) then favors increased (reduced) rainfall over the Yangtze River Valley that corresponds to a strong (weak) EASM, thereby leading to the significant positive (negative) KE–EASM relationship during this period. This change in the relationships of summer KE SSTAs with the EASWJ and WNPSH may be attributed to the increased KE SST variability associated with an enhanced Pacific Decadal Oscillation (PDO) in summer during P2, which is most probably induced by the stronger North Pacific Oscillation (NPO)-like atmospheric forcing, especially its southern pole (SP), in the preceding spring during this period. The spring NPO-like SP forces the KE SSTAs and PDO more directly during the following summer and can thus have been a better precursor for the following EASM than the full NPO-like dipole after the late 1980s.

On the morning of 21 June 1978, exceptional sea level oscillations with a trough‐to‐crest height of 6 m and a period of 10–20 min were observed in Vela Luka Bay. Slightly less pronounced variability was observed in a wider middle and south Adriatic east coastal area and, with some delay, along the west coast. In this paper, one of the original hypotheses put forward to interpret the event, relating it to a mesoscale air pressure disturbance, is reconsidered by using all the available data as well as state‐of‐the‐art meteorological and oceanographic models. A fresh look at the meteorological data confirms that the atmospheric disturbance propagated at about 22 m/s in a northeastward direction. Additionally, the data suggest that it had the shape of the boxcar function characterized by an air pressure offset of 3 mbar and duration of 10 min. The meteorological model employed (Weather Research and Forecasting (WRF)‐Advanced Research WRF) proves unable to reproduce the mesoscale disturbance coinciding with the surge, but it shows that the background atmospheric conditions were favorable for the development of such disturbances. The oceanographic model Advanced Circulation Model for Shelves, Coasts and Estuaries (two‐dimensional depth integrated), forced by the described air pressure disturbance, successfully reproduces sea level variability in Vela Luka Bay reaching a few meters and thus surpassing the inverted barometer response by two orders of magnitude. The enhancement appears to be due to a four‐phase process. The model also suggests that the scattering due to the variable bathymetry and the reflection from the east Adriatic coast resulted in waves that returned towards the west coast and generated considerable sea level activity there.