Abrupt reconfiguration (reconnection) of solar magentic fields is leading to active phenomena (flares and CMEs) which are efficient particle accelerators. These particles populations contain around 30% of total released magnetic energy. In the standard model of a solar flare particles (mainly electrons) transport energy to the chromosphere where they experience Coulomb collisions with ambient plasma leading to emission of bremsstrahlung (non-thermal radiation) and heating (thermal radiation). Other part of particles may escape the Sun and propagate in the interplanetary space where they can be investigated in situ. The multi-messenger analyses of energetic particles were proven to give extremely interesting results. On of the best examples is the existence of third radiation belt in the Earth magnetosphere which was supported by in situ (STEP-F) and remote (SphinX) instruments onboard CORONAS-Photon satellite. Recently, in February 2020, Solar Orbiter has been launched carrying onboard ten scientific instruments. Among them Spectrometer/Telescope for Imaging X-rays (STIX) and Energetic Particle Detector (EPD) are instruments that allow to observe energetic particles accelerated in the solar corona. STIX is measuring X-rays in the energy range 4-150 keV, in 32 energy channels, which gives opportunity for investigation of non-thermal part of a solar flare spectrum. From spectral analysis of STIX data we can obtain properties of non-thermal particle beams and compare them to remote data from ground based radio observatories (Ondrejov observatory). The comparison gives reach information about particles propagating down to the chromosphere (X-rays) and up to the solar corona and, eventually, interplanetary space (radio). Particles propagating in the interplanetary space may reach EPD onboard Solar Orbiter allowing for linking their properites observed in the acceleration site and after traveling large distance. The reacheness of data allows to investigate non-thermal particles (electrons in this case) properties from several points of view. Here we present few case studies of very interesting events that allow to look from a new perspective to flare-related particles acceleration and propagation problems.

We describe a new capability of the Wang-Sheeley-Arge (WSA) model to routinely derive the coronal separatrix web (S-web) as a standard data product. We use one Carrington rotation (CR) to demonstrate this tool, in which we derive the global coronal magnetic field and S-web using a sequence of synchronic photospheric field maps from the Air Force Data Assimilative Photospheric Flux Transport (ADAPT) model. We also derive a time series that quantitatively relates the in situ observed solar wind at ACE with the squashing factor ($Q$) derived at the model-determined source region of the solar wind, where high $Q$ indicates the source region proximity to a magnetic separatrix or quasi-separatrix layer (QSL) in the corona. We demonstrate that all intervals of high $Q$, including one associated with a pseudostreamer, correlate with times when the charge state and abundance measurements at L1 are enhanced and highly structured. This is predicted to occur for solar wind originating from the open-closed boundary, where closed field plasma with escapes out into the solar wind via interchange reconnection with open fields. Further, we relate $Q$ to expansion factor ($f_s$) and coronal hole boundary distance ($\theta_b$, DCHB), which are longstanding parameters used to empirically derive solar wind speed. We demonstrate that $Q$, though related to $f_s$ and DCHB, is a separate metric of the coronal magnetic field topology and a unique probe of solar wind formation. We conclude by highlighting the novel capabilities of this tool, and we discuss future uses for space weather forecasting.

    Project Shooting Interplanetary Garbage: Material Ablation conducts an in-depthanalysis of the solutions for space debris in Earth’s orbit. This work focuses on de-orbitingman-made debris between one and ten centimeters present within Low Earth Orbit. Withhundreds of thousands of objects around this size, each moving at high speeds of ten kilometersper second, even the smallest pieces can cause massive damage to satellite communicationsystems and other spacecraft.    Solutions for space debris can be categorized as either mitigation or remediation.Mitigation strategies involve preventing, avoiding, or protecting against space debris. However,actively moving or using the debris, known as remediation, is a more long-term and effectivesolution. Our plan is remedial and focuses on de-orbiting current space debris, causing it toburn up in Earth’s atmosphere. Of the various options we researched, the space-based laser wasthe most viable due to its combination of low price and superior performance. Our satellitewould be equipped with an excimer laser set on the NASA Robotic Servicing Arm. A convexlens would collimate and reduce the divergence of the laser beam. By firing powerful, 248nanometer pulses of ultraviolet light at debris, ablation would occur, slowing the target downand causing it to de-orbit significantly sooner. In order to power this laser, solar panels wouldbe stationed on each side of the spacecraft, thus supplying the energy needed to power the laseractivities.    We simulated a model of space debris by creating a graph of particles with differentpositions and orbital velocities, with one being the moving satellite and the rest representingorbiting debris. Our algorithm identified the distance to the closest debris and the angle thatthe laser had to be positioned to hit the debris, which was represented by a line drawn betweenthe particle and the satellite. Ultimately, as more spacecraft are launched into space, the risk ofcollisions increases. Orbital debris remains problematic and this proposed laser-based satellitewould be an efficient and inexpensive solution.

A document by Ryan Joseph M. Felicidario. Click on the document to view its contents.

Existing comparative studies on conceptual hydrological model structures have generally focused on streamflow, with less attention to evapotranspiration (ET). Studies have shown that an appropriate ET representation in conceptual models is crucial for obtaining reliable hydrological simulations and predictions, especially under climate change and for ungauged basins. To address this gap, we investigated 30 conceptual models in terms of how they represent ET process and their ability on reproducing two state-of-the-art ET products (PML-V2 and FLUXCOM-X-BASE) in 507 catchments across different climates and landscapes. We found significant differences in ET simulation performance between models with different ET representations. Models employing a linear-relationship between ET from soil and soil moisture storage generally outperformed those that equate ET from soil directly with potential ET (PET). For each catchment, at least one model could well reproduce at least one ET product. Models’ performance in the ET simulation varied with climatic and vegetation characteristics. In humid catchments with summer-dominated rainfall or mild rainfall seasonality, a concise linear-type ET representation could effectively replicate ET products. Adding parameter(s) controlling the long-term ratio between ET and PET could further improve performance. In humid winter-rainfall-dominated catchments, explicitly representing an interception evaporation (Ei) component and constraining Ei by the interception capacity or storage was critical for reproducing ET products. In some arid catchments, considering the contribution of lower storage to ET generation was necessary to reproducing ET products. This study provides insights into how to appropriately represent the conversion process from PET and precipitation to ET in various climates.

Methane (CH4) consumption in well-drained soils is a key process for global CH4 sink. Yet, the temporal and depth-specific CH4 oxidation is rarely described despite being critical for the surface net CH4 uptake. Here, we linked year-round field observations of CH4 fluxes in well-drained cultivated soils with subsurface CH4 concentrations, laboratory incubations, and process-based modeling to uncover these mechanisms. Field observed CH4 fluxes ranged from –0.43 to 0.19 mg CH4 m-2 day-1 with an average of –0.15 ± 0.01 mg CH4 m-2 day-1 over the year-round study period. Much lower CH4 fluxes were observed in summer than in winter, indicating significant seasonal variations. Modeling using the CoupModel to simulate soil temperatures and water content as drivers, along with an analytic reaction-based model to simulate CH4 fluxes, show that the depth penetration of atmospheric CH4 is a critical parameter for defining a CH4 oxidation reaction zone below the surface. The thickness of the reaction zone varied seasonally. Sensitivity tests of CH4 concentrations and oxidation profiles in response to contrasting precipitation scenarios reveal that CH4 oxidation during drought scenario is increased at deeper depths due to higher CH4 availability. However, CH4 oxidation in near-surface layers decreased due to low soil water content, resulting in a significantly lower net surface CH4 uptake. Our findings suggest that both the depth-specific CH4 oxidation profile and net surface CH4 fluxes will likely change under future warmer and drier periods.

This poster shows the means and measures taken to increase female attendance in the Geo-INQUIRE training program and their impact. Geo-INQUIRE is an EU-funded Earth Science project that focuses on the integration and homogenization of many different kinds of services (data, software, HPC, etc.) to facilitate (interdisciplinary) work in fields such as  seismology, tsunami research and volcanology, risk assessment, and analysis. Geo-INQUIRE addresses both big data challenges and HPC software challenges, offering access to high-end machines in Europe (e.g., Leonardo, Marenostrum5, SuperMUC-NG). The aim of the training program is to increase awareness of the Geo-INQUIRE services, show how they can be used interdisciplinary and provide training to support proposals for the Transnational Access (TA) Calls that Geo-INQUIRE is issuing regularly. At the start of this 4-year project, two goals were proposed by Geo-INQUIRE’s Equality and Diversity Panel (EDIP): to aim for at least 40% female engagement and 35% participants from widening countries. Recent studies (Ermert et. al, 2023) have shown that females are still underrepresented in Earth Science, especially in authorships of publications, a key factor of career advances. Many Geo-INQUIRE services focus on High-Performance Computing or Big Data analysis, leading to skepticism if those ambitious goals could be reached. We implemented several targeted measures to increase female engagement including making asynchronous training options available by providing recordings, ensuring that trainings were lead by female lecturers  to provide role models  or to explicitly state in the training announcements that “Geo-INQUIRE promotes diversity and inclusion within the scope of the project”. We have managed to attract one third female applications in nearly all trainings, and surpassed the 40% goal in 60% of the training events, going up to 65+% for the first two “FAIR” training events that Geo-INQUIRE also offers.We believe that setting ambitious gender balance goals and putting targeted effort into achieving these goals  has substantially increased female engagement in Geo-INQUIRE. We hope that the trainees from today will become the trainers of tomorrow and propose to extend this approach to other HPC training programs like the PRACE training program to increase the number of female researchers in High-Performance Computing. Geo-INQUIRE is funded by the European Commission under project number 101058518 within the HORIZON-INFRA-2021-SERV-01 call.References:Ermert, L. A., Koroni, M., and Korta Martiartu, N.: Quantifying gender gaps in seismology authorship, Solid Earth, 14, 485–498, https://doi.org/10.5194/se-14-485-2023, 2023.

A document by Suma Bhanu Battula. Click on the document to view its contents.

Arctic Amplification, the accelerated warming of the Arctic compared to lower latitude, remains incompletely understood, particularly regarding the role of clouds. In this study, we analyze 26 years of Downwelling Longwave Radiation (DLR) measurements from an Extended-range Atmospheric Emitted Radiance Interferometer (E-AERI) at the U.S. Department of Energy’s North Slope Alaska site. Our analysis reveals a pan-spectral increase in DLR under all sky conditions, primarily driven by an enhanced greenhouse effect from thick/low clouds and greenhouse gases. Changes in radiance, rather than cloud fraction, dominate these trends, suggesting fundamental shifts in atmospheric emissivity and/or temperature. Comparative analysis between mid- and high-latitudes demonstrates that cloud impacts the longwave surface energy balance differently between the two locations. In the Arctic, the pan-spectral increase in DLR trend dampens out the radiative cooling of the warming surface, contributing significantly to Arctic Amplification. Consistent positive trends are found in the far-infrared, a spectral region particularly sensitive to the dry and cold Arctic’s atmosphere and of significant interest in the current warming context. Additionally, we observe a relatively weaker DLR trend in the ozone absorption band under every sky condition, indicating a tropospheric ozone radiative forcing in the Arctic climate.

Monitoring and understanding volcano-seismic signals like long-period events and tremor can improve eruption forecasting. Rotational sensors are newly developed instruments that offer enhanced monitoring capabilities by providing additional information on rotational motion and enabling the differentiation of wave types and seismic sources. In 2019 a seismic array and a rotational sensor along with a co-located seismometer (6C) recorded for 25 days spanning an eruption with ash emissions and Strombolian activity, characterized by long-period events and tremor. We compare the performance of a rotational sensor to those of a seismic array by determining the back azimuth of seismic events. As a reference for our comparison we use the routine event locations from the Istituto Nazionale di Geofisica e Vulcanologia-Osservatorio Etneo (INGV-OE) network on Mt. Etna volcano, Italy. We find that tremor back azimuths obtained from the north and vertical array components fit the INGV-OE reference best during higher eruption tremor amplitudes, while the combined rotational sensor and seismometer (6C) directions provide the most accurate results at the eruption start with low amplitudes. Long-period event directions derived using the north and vertical components of the array are closer to the network reference than those from the east and 6C. The east component results show a systematic bias, likely due to topographic effects, a heterogeneous subsurface medium or nearby faults. Our results demonstrate the contribution of rotational sensors in the understanding and monitoring of volcanic activity. More studies on active volcanoes are needed to better assess their potential to complement conventional seismic investigations.

The time needed by deep convection to bring the atmosphere back to equilibrium is called convective adjustment timescale or simply adjustment timescale, typically denoted by $ au$. In the Community Atmospheric Model (CAM), $tau$ is the convective available potential energy (CAPE) relaxation timescale and is 1 hour, worldwide. Observational evidence suggests that $tau$ is generally longer than 1 hour. Further, continental and oceanic convection are different in terms of the vigor of updrafts and can have different longevities. So using $tau=1$ hour worldwide in CAM has two potential caveats.   A longer $tau$ improves the simulation of the mean climate. However, it does not address the land-ocean heterogeneity of atmospheric deep convection. We investigate the prescription of two different CAPE relaxation timescales for land ($tau_L=1$ hr) and ocean ($tau_O=1$ to $4$ hrs). It is arguably an extremely crude parameterization of boundary layer control on atmospheric convection. We contrast a suite of 5-year-long simulations with two different $tau$ for land and ocean to having one $tau$ globally. The choice of longer $tau$ over ocean is guided by previous studies and inspired by observational pieces of evidence. Nonetheless, to complement our variable $tau_O$ experiments, we perform a simulation with $tau_O=1$ hr and $tau_L=4$ hrs. Most importantly, our key findings are immune to the exact values of prescribed $tau_L$ and $tau_O$. The CAM model, with two $tau$ values ($tau_O>tau_L$), improves convective-stratiform rainfall partitioning and the Madden–Julian oscillation (MJO) propagation characteristics. With $tau_O

The Atlantic Meridional Overturning Circulation (AMOC) impacts temperatures, ecosystems, and the carbon cycle. However, how AMOC affects the carbon cycle remains poorly understood, in part because the respective contributions of different physical and biological mechanisms that impact carbon storage in the ocean are not typically diagnosed in climate models. Here we explore modeled effects of an AMOC shutdown on Dissolved Inorganic Carbon (DIC) in the ocean by applying a new decomposition that explicitly calculates preformed and regenerated DIC components and separates physical and biological contributions. An extensive evaluation of the method in transient simulations finds that, in most cases, it is accurate and reliable, especially for basin-wide changes, whereas errors can be significant at global and local scales. In contrast, estimates of respired carbon based on Apparent Oxygen Utilization lead to large errors and are generally not reliable. In response to a shutdown of the AMOC, ocean carbon increases and then decreases, leading to opposite changes in atmospheric CO2. DIC changes are dominated by opposing changes in biological carbon storage. Whereas regenerated components increase in the Atlantic and dominate the initial increase in global ocean DIC, preformed components decrease in the other ocean basins and dominate the long-term DIC decrease. Biological disequilibrium is an important contribution to preformed carbon changes. Biological saturation carbon decreases in the Pacific, Indian, and Southern Oceans due to a decrease in surface alkalinity. The spatial patterns of the DIC components and their changes in response to an AMOC collapse are presented.

Dynamic topography results in uplift and subsidence events on Earth’s surface with amplitudes on the order of a kilometer over time periods of a few million years. These vertical motions are known to have influenced ice sheet evolution, but how dynamic topography has controlled the current state of present ice sheets is unknown. Here, we explore this by running ice sheet models to their equilibrium state after removing present-day dynamic topography. We find that Antarctic ice cover is significantly different without dynamic topography; the Marie Byrd Land sector of West Antarctica loses 1.542 ×106 gigatonnes of ice, while the Weddell Sea sector gains 1.23623 ×106 gigatonnes. In Greenland, we see ice loss in the east and large sectors of the ice sheet become marine based. Taken together, these findings indicate that present-day dynamic topography has played a major role in the equilibrium geometries of modern ice sheets.

Hypoxia is an increasing concern along the Northeast Pacific continental margin, driven by oxygen (O₂) declines related to a warming climate. Despite a declining North Pacific O₂ inventory, historical observations of hypoxia on the central coast of British Columbia, Canada, were rare before 2020. However, recent observations from Queen Charlotte Sound (QCS)—a 120 km-wide shelf sea supporting an ecologically and economically significant ecosystem—indicate that hypoxia is now an emerging issue in this region. This study synthesizes regional observations from numerous platforms to describe O₂ distributions during 2022 and 2023, identifying persistent shelf-wide hypoxia during summer months, including periods of statistically defined extreme hypoxia. Comparisons with the hydrographic record from 2003–2023 show that O₂ concentrations were lower and hypoxia more common in 2022/23 than in previous years. Long-term deoxygenation trends of approximately 5–10 μmol kg⁻¹ per decade are identified at isopycnals representing QCS deep waters, in addition to seasonal and interannual variability of similar magnitude. On annual and seasonal timescales, upwelling strength, timing, and O₂ consumption modulate O₂ variability, while the offshore supply of O₂ modulates variability on interannual and decadal timescales. This low-frequency signal propagates from the Northwestern Pacific via North Pacific Gyre circulation with an 8-year lag. The North Pacific Gyre Oscillation (NPGO) is also identified as a strong driver of O₂ variability through its influence on upwelling. The regional emergence of hypoxia has resulted from progressive O₂ declines rather than a sudden shift, and projections suggest that summer hypoxia will become the norm by 2050 in the absence of regional O₂ recovery.

We have recently argued that a simple nonlinear law could be important for the origin of the Universe resulting in fractal or multifractal features [1]. Various fractal scaling models of the large-scale mass distribution have already been proposed. The expected universal multifractal function for galaxies is similar to that identified by NASA's Voyager mission in the Solar System [2]. Now we apply the similar method to determine a reliable multifractal spectrum of distribution of galaxies on cosmological scales, based on selected observations from a million of galaxies in the Redshift Catalog (June 2008) [3]. We show that the observed spectrum is consistent with the weighted oneor two-scale Cantor set models characteristic for turbulence in laboratory and inside the Sun's heliosphere immersed in the very local interstellar medium. However, the total degree of multifractality ∆ ≈ 0.2 is much smaller then that inside the heliosphere. This would be characteristic for a simple linear fractal scaling of galaxy distribution, but somewhat varying for nearby (∆ ≈ 0.1) and the most remote galaxies (∆ ≈ 0.2) receding from our Solar System. The parameters p ≈ 0.45 and λ ≤ 1/2 for one-scale model are apparently related to some voids in the large-scale distribution of matter. A possible asymmetry (A ≈ 0.75) of the total spectrum for two-scale weighted Cantor set (A ̸ = 1) could admittedly be attributed to some deviations from the Hubble's law for the ideal uniform expansion of the Universe.

The increasing frequency of wildfires in California, driven by climate change, poses unclear risks from repeated wildfire smoke exposure. This study explores the ”recovery period,” the time between smoke waves, which may offer respite from smoke impacts. We examine trends in wildfire smoke wave frequency, duration, and recovery periods in California from 2006 to 2020, aiming to assess repeated exposures and create a framework to explore health impacts via recovery periods. We define a smoke wave as two or more consecutive days with wildfire-specific fine particulate matter (PM2.5) >1 µg/m³, at the census tract level. Recovery periods are calculated as the days between smoke waves, ending with the first wave of 2021. We also examine community characteristics such as income, race, and education. From 2006–2010 to 2016–2020, we observed a 60% reduction in recovery periods, an 85% increase in smoke events, and longer durations. Spatial variability was substantial across census tracts, with the greatest reductions in recovery periods in Southern and Central Valley regions. Northern California, with the shortest recovery periods, showed minimal changes. Communities with higher proportions of minority race groups, single female householders, and lower incomes experienced the largest reductions in recovery period length. This study introduces a framework to assess the repeated impacts of smoke waves, highlighting changing spatio-temporal patterns. Incorporating recovery periods into health risk assessments can guide public health strategies to address compounding risks from wildfire smoke.

In this work, a team of globally distributed space science researchers come together to voice their perspectives on space weather research globally and locally. We highlight the importance of studying Heliophysics and space weather research efforts and discuss the challenges the field faces in different parts of the world. We emphasize the importance of focusing on local matters, emphasizing that space weather science can look and mean different things in various parts of the world. Local stories and regional challenges are often lost in chasing the broadly defined issues by the community. We highlight this issue and the importance of global voices, focusing on three different regions: India, Africa, and Latin America. The regions are demographically and culturally distinct, and each region offers a unique perspective on space weather research. We then discuss these challenges in terms of data, software, and technological infrastructure, diving into the guidelines and vision of the globally united space weather research community. This leads to a discussion of shared global challenges and an offering of solutions in today's digital world incorporating open science initiatives. Lastly, we describe what emerging technologies such as artificial intelligence and augmented/virtual reality can offer the space weather community, taking inspiration from other fields.

A document by Ankita. Click on the document to view its contents.