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  • Journal article
    Krasnoselskikh V, Jebaraj IC, Cooper TRF, Voschepynets A, de Wit TD, Pulupa M, Mozer F, Agapitov O, Balikhin M, Bale SDet al., 2025,

    Plasma Instability in Front of Ejected Energetic Electrons and Type III Solar Radio Bursts

    , ASTROPHYSICAL JOURNAL, Vol: 990, ISSN: 0004-637X
  • Journal article
    Rovithakis A, Burke E, Burton C, Kasoar M, Grillakis MG, Seiradakis KD, Voulgarakis Aet al., 2025,

    Estimating future wildfire burnt area over Greece using the JULES-INFERNO model

    , NATURAL HAZARDS AND EARTH SYSTEM SCIENCES, Vol: 25, Pages: 3185-3200, ISSN: 1561-8633
  • Journal article
    Sakellaris IA, Bartzis JG, Grillakis E, Bakouros IL, Kyriazanos D, Saraga DE, Voulgarakis A, Maggos Tet al., 2025,

    Simulation of Air Pollution Produced by Forest Fires Using the WRF-SFIRE-CHEM Model in Greece: Study Cases

    , FIRE TECHNOLOGY, ISSN: 0015-2684
  • Journal article
    Elsden T, Southwood DJ, Allanson O, Archer MO, Hartinger MD, Wright ANet al., 2025,

    Theory and modeling of large scale plasmapause surface waves

    , Journal of Geophysical Research: Space Physics, Vol: 130, ISSN: 2169-9380

    The plasmapause in Earth's magnetosphere represents the boundary between the plasma which co-rotates with the Earth (plasmasphere), and the more tenuous plasmatrough outside. The density change across the plasmapause can be large, changing by approximately 1–2 orders of magnitude depending on the prevailing conditions. This would suggest it to be a location where magnetohydrodynamic (MHD) surface waves can form, and indeed, this has been proposed in previous works to explain ultra-low frequency (ULF) wave observations around the plasmapause location. The main question is how such a large scale surface wave on the plasmapause would be excited. In this paper, we propose a model whereby surface waves at the plasmapause are driven by energy input from the magnetopause through solar wind driving. We derive an analytical form for the amplitude of these surface waves with this new driven boundary condition at the magnetopause. The excitation of these waves is then tested in several MHD simulations, where the model geometry, wavenumbers and temporal dependence of the magnetopause driver are varied. We establish that surface waves on the plasmapause can be excited by driving from the magnetopause, and that this still occurs with impulsive and continuous broadband driving. The azimuthal scale of the wave is a critical factor for this excitation, with longer azimuthal scales more favorable for driving larger amplitude surface waves. This mechanism provides new insight for how large scale and large amplitude ULF waves can access the inner magnetosphere, with potential implications for their interaction with radiation belt particles.
  • Journal article
    Panditharatne S, Cox C, Song R, Siddans R, Bantges R, Murray J, Fox S, Fox C, Brindley Het al., 2025,

    Exploiting airborne far-infrared measurements to optimise an ice cloud retrieval

    , Atmospheric Chemistry and Physics, Vol: 25, Pages: 9981-9998, ISSN: 1680-7316

    Studies have indicated that far-infrared radiances hold significant information about the microphysics of ice clouds, particularly the ice crystal habit. In support of the European Space Agency's Far-Infrared Outgoing Radiation Understanding and Monitoring mission, we perform the first retrieval on an observation of coincident upwelling far- and mid-infrared radiances taken from an aircraft above a cirrus cloud layer. Four retrievals are performed: including and neglecting the far-infrared portion of the spectrum and assuming two different habit mixes. Results are compared to in situ measurements of the cloud optical thickness, cloud top height, cloud effective radius, and habit distributions. We find that despite the known limitations of ice cloud optical property models, all the retrievals show agreement within the in situ measurements of the cloud optical thickness, cloud top height, and cloud effective radius. However, the inclusion of the far-infrared enables a distinction between two different habits that is not possible using only mid-infrared channels. Furthermore, in this case study, the uncertainty in the retrieval of cloud top height and cloud optical thickness halves with the inclusion of the far-infrared. As with other studies, we also see an additional degree of freedom for the temperature and water vapour retrievals. Our study highlights the need for the improvement of current ice cloud optical models, with the radiance residuals from the converged retrievals still exceeding the instrument uncertainty within the far-infrared. However, it provides observational support for the theoretical improvement that far-infrared observations could bring to retrievals of ice cloud properties.
  • Journal article
    Frankignoul C, Hall R, Kwon Y-O, Czaja Aet al., 2025,

    On the Atmospheric Response to Oyashio Extension Front Disturbance and Mesoscale SST Variations

    , JOURNAL OF CLIMATE, Vol: 38, Pages: 5055-5066, ISSN: 0894-8755
  • Journal article
    Koike M, Takigawa M, Morimoto S, Adachi K, Aizawa T, Chandra N, Fujita R, Goto D, Ishidoya S, Ishijima K, Ito A, Kawai K, Kanaya Y, Kim Y, Kinase T, Kondo Y, Machida T, Matsui H, Miyakawa T, Mochida M, Mori T, Moteki N, Murayama S, Ohata S, Oshima N, Patra PK, Taketani F, Tobo Y, Tohjima Y, Toyoda S, Tsuboi K, Rui OC, Yahara K, Yamaji K, Yoshida A, Zhu Cet al., 2025,

    Studies of atmospheric climate forcers in the Arctic during the ArCS II project

    , POLAR SCIENCE, Vol: 45, ISSN: 1873-9652
  • Journal article
    Pathak N, Ergun RE, Vo T, Chasapis A, Qi Y, Ahmadi N, Newman D, Schwartz SJ, Eriksson S, Usanova ME, George Het al., 2025,

    Observations of Large-Amplitude Parallel Electric Fields in the Turbulent Magnetotail

    , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 130, ISSN: 2169-9380
  • Journal article
    Kawaguchi K, Ceppi P, 2025,

    Responses to Lower-Tropospheric Stability Dominate Intermodel Differences in the Historical Pattern Effect

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 52, ISSN: 0094-8276
  • Journal article
    Toumi R, Sparks N, 2025,

    The Hurricane Damage Index (HurDI)

    , Journal of Catastrophe Risk and Resilience, Vol: 03, ISSN: 3049-7604

    Statistical hurricane risk assessments make long-term multi-decadal stationary climate assumptions, but there is large hurricane variability in the risk. It would be useful to also better estimate the “current” risk. The hurricane damage index (HurDI), is proposed as a measure of the underlying non-stationary risk. The HurDI is defined as the normalised annual average damage calculated with a stochastic wind only model, a single damage function, and uniform exposure across the continental U.S. The stochastic model is climate conditioned by weighting the historical basin hurricane counts, potential intensity, and tracks. The weights are chosen to give the best persistence forecast for each parameter for the next five years. There has been a substantial increase of the hurricane risk as measured by the HurDI. In 2024, the index was at a record high of 188, with a reference value of 100 in 1989. The HurDI is a dynamic view of risk based on the hurricane variability only and can be compared to U.S. property catastrophe reinsurance rates. There are periods of varying difference between the rates and the HurDI reflecting the volatile market cycles.
  • Journal article
    Bowen TA, Mallet A, Dunn CI, Squire J, Chandran BDG, Meyrand R, Davis N, Dudok de Wit T, Bale SD, Badman ST, Sioulas Net al., 2025,

    Formation of magnetic switchbacks via expanding Alfvén waves

    , ASTRONOMY & ASTROPHYSICS, Vol: 700, ISSN: 0004-6361
  • Journal article
    Norgren C, Chen L-J, Graham DB, Bessho N, Egedal J, Richard L, Khotyaintsev YV, Shuster J, Toledo-Redondo S, Lavraud B, Hasegawa H, Eastwood JP, Hesse M, Liu Y-H, Holmes JC, Argall Met al., 2025,

    Electron and ion dynamics in reconnection diffusion regions

    , Space Science Reviews, Vol: 221, ISSN: 0038-6308

    Magnetic reconnection is a fundamental plasma process responsible for the sometimes explosive release of magnetic energy in space and laboratory plasmas. Inside the diffusion regions of magnetic reconnection, the plasma becomes demagnetized and decouples from the magnetic field, enabling the change in magnetic topology necessary to power the energy release over larger scales. Since it was launched in 2015, the Magnetospheric MultiScale (MMS) mission has significantly advanced the understanding of the particle dynamics key to magnetic reconnection by providing high-resolution, in-situ measurements able to resolve ion and electron kinetic scales, i.e. a fraction of a gyroradius, that have confirmed theoretical predictions, revealed new phenomena, and refined existing models. These breakthroughs are critical for understanding not only space plasmas but also laboratory and astrophysical plasmas where magnetic reconnection occurs. In this work, we review the ion and electron dynamics occurring within the diffusion regions, in the inflow, along the separatrices, and downstream of the diffusion regions, in different reconnection configurations: symmetric, asymmetric, antiparallel, and guide field reconnection.
  • Journal article
    Lewis ZM, Stephenson P, Beth A, Galand M, Kallio E, Moeslinger Aet al., 2025,

    Cometary ion dynamics at 67P: a collisional test-particle approach with Rosetta data comparison

    , Monthly Notices of the Royal Astronomical Society, Vol: 541, Pages: 3590-3605, ISSN: 0035-8711

    The Rosetta spacecraft escorted comet 67P/Churyumov–Gerasimenko for two years, gathering a rich and variable data set.Amongst the data from the Rosetta Plasma Consortium (RPC) suite of instruments are measurements of the total electron densityfrom the Mutual Impedance Probe (MIP) and Langmuir Probe (LAP). At low outgassing, the plasma density measurements canbe explained by a simple balance between the production through ionization and loss through transport. Ions are assumed totravel radially at the outflow speed of the neutral gas. Near perihelion, the assumptions of this field-free chemistry-free modelare no longer valid, and plasma density is overestimated. This can be explained by enhanced ion transport by an ambipolarelectric field inside the diamagnetic cavity, where the interplanetary magnetic field does not reach. In this study, we explore thetransition between these two regimes, at intermediate outgassing (5.4 × 1026 s−1), when the interaction between the cometaryand solar wind plasma influences the transport of the ions. We use a 3D collisional test-particle model, adapted from Stephensonet al. to model the cometary ions with input electric and magnetic fields from a hybrid simulation for 2.5–3 au. The total plasmadensity from this model is then compared to data from MIP/LAP and to the field-free chemistry-free model. In doing so, wehighlight the limitations of the hybrid approach and demonstrate the importance of modelling collisional cooling of the electronsto understand the ion dynamics close to the nucleus.
  • Journal article
    Page B, Lecacheux A, Pulupa M, Bale SDet al., 2025,

    Calibration of Electrically Short Antennas Using the <i>l</i>=2 Spherical Harmonic Expansion Coefficients of the Radio Brightness Distribution on the Sky Between 0.5 and 6.8 MHz

    , RADIO SCIENCE, Vol: 60, ISSN: 0048-6604
  • Journal article
    Kretzschmar M, Brochot J-Y, Horbury TS, Rackovic K, Maksimovic M, Alexandrova O, Bonnin X, Jannet G, O'Brien H, Crabtree A, Morris J, Krasnoselskikh V, Dudok de Wit T, Le Contel O, Chust T, De Gelis P-M, Da Silva Goncalves L, Fauchon-Jones Eet al., 2025,

    The Solar Orbiter merged magnetic field

    , ASTRONOMY & ASTROPHYSICS, Vol: 699, ISSN: 0004-6361
  • Journal article
    Pulupa M, Bale SD, Jebaraj IC, Romeo O, Krucker Set al., 2025,

    Highly Polarized Type III Storm Observed with Parker Solar Probe

    , ASTROPHYSICAL JOURNAL LETTERS, Vol: 987, ISSN: 2041-8205
  • Journal article
    Niwa Y, Tohjima Y, Terao Y, Saeki T, Ito A, Umezawa T, Yamada K, Sasakawa M, Machida T, Nakaoka SI, Nara H, Tanimoto H, Mukai H, Yoshida Y, Morimoto S, Takatsuji S, Tsuboi K, Sawa Y, Matsueda H, Ishijima K, Fujita R, Goto D, Lan X, Schuldt K, Heliasz M, Biermann T, Chmura L, Necki J, Xueref-Remy I, Sferlazzo Det al., 2025,

    Multi-observational estimation of regional and sectoral emission contributions to the persistent high growth rate of atmospheric CH4 for 2020-2022

    , Atmospheric Chemistry and Physics, Vol: 25, Pages: 6757-6785, ISSN: 1680-7316

    Atmospheric methane (CH4) growth rates reached unprecedented values in the years 2020-2022. To identify the main drivers of this increase, an inverse modeling study estimated regional and sectoral emission changes for 2016-2022. Three inverse estimates based on different sets of atmospheric CH4 observations (surface observations only, surface and aircraft observations, and GOSAT observations) consistently suggest notable emission increases from 2016-2019 to 2020-2022 in the tropics (15° S-10° N) (10-18 Tg CH4 yr-1) and in northern low latitudes (10-35° N) (ca. 20 Tg CH4 yr-1), the latter of which likely contributed to the growth rate surge from 2020. The emission increase in the northern low latitudes is attributed to emissions in South Asia and northern Southeast Asia, which abruptly increased from 2019 to 2020, and elevated emissions continued until 2022. Meanwhile, the tropical emission increase is dominated by Tropical South America and Central Africa, but emissions were continuously increasing before 2019. Agreement was found in the sectoral estimates of the three inversions in the tropics and northern low latitudes, suggesting the largest contribution of biogenic emissions. Uncertainty reductions demonstrate that the flux estimates in Asia are well constrained by surface and aircraft observations. Furthermore, a sensitivity test with the probable reduction of OH radicals showed smaller emissions by up to 2-3 Tg CH4 yr-1 in each Asian region for 2020, still suggesting notable emission contributions. These results highlight the importance of biogenic emissions in Asian regions for the persistent high growth rate observed during 2020-2022.
  • Journal article
    Wilson III LB, Mitchell JG, Szabo A, Jebaraj IC, Stevens ML, Malaspina DM, Berland GD, Kouloumvakos A, Bale SD, Livi R, Halekas JS, Cohen CMSet al., 2025,

    Large-amplitude Whistler Precursors and >MeV Particles Observed at a Weak Interplanetary Shock by Parker Solar Probe

    , ASTROPHYSICAL JOURNAL, Vol: 987, ISSN: 0004-637X
  • Journal article
    Ren T, Yang P, Brindley HE, L'Ecuyer TS, Maestri Tet al., 2025,

    Temperature-Dependent Optical Properties of Ice Crystals in the Far-Infrared Regime

    , GEOPHYSICAL RESEARCH LETTERS, Vol: 52, ISSN: 0094-8276
  • Journal article
    Goodwin P, Williams RG, Ceppi P, Cael BBet al., 2025,

    Climate Feedbacks Derived From Spatial Gradients in Recent Climatology

    , JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, Vol: 130, ISSN: 2169-897X
  • Journal article
    Turc L, Archer MO, Zhou H, PfauKempf Y, Suni J, Kajdič P, BlancoCano X, Dahani S, Battarbee M, Raptis S, Liu TZ, Zhang H, Escoubet CP, LaMoury AT, Tao S, Lipsanen V, Hao Y, Palmroth Met al., 2025,

    Interplay between a foreshock bubble and a hot flow anomaly forming along the same rotational discontinuity

    , Geophysical Research Letters, Vol: 52, ISSN: 0094-8276

    Solar wind directional discontinuities can generate transient mesoscale structures such as foreshock bubbles and hot flow anomalies (HFAs) upstream of Earth's bow shock. These structures can have a global impact on near-Earth space, so understanding their formation conditions is essential. We investigate foreshock transient generation at a rotational discontinuity using a global 2D hybrid-Vlasov simulation. As expected, a foreshock bubble forms on the sunward side of the discontinuity. Later, when the discontinuity reaches the shock, new structures identified as HFAs develop, despite the initial discontinuity not being favorable to HFA formation. We demonstrate that the foreshock bubble provides the necessary conditions for their generation. We then investigate the evolution of the transient structures and the large-scale bow shock deformation they induce. Our results provide new insights on the formation and evolution of foreshock transients and their impact on the shock.
  • Journal article
    Kartavykh Y, Rodriguez-Garcia L, Heber B, Wimmer-Schweingruber RF, Trotta D, Gieseler J, Droege H, Kollhoff A, Droege W, Kilpua E, Horbury T, Espinosa Lara F, Gomez-Herrero R, Rodriguez-Pacheco J, Lario D, Dresing N, Klassen A, Vainio Ret al., 2025,

    A statistical study of energetic particle events associated with interplanetary shocks observed by Solar Orbiter in solar cycle 25

    , ASTRONOMY & ASTROPHYSICS, Vol: 699, ISSN: 0004-6361
  • Journal article
    Phan TD, Romeo OM, Drake JF, Larson D, Oieroset M, Eriksson S, Lavraud B, Bale SD, Rahmati A, Livi R, Whittlesey P, Pulupa M, Huang J, Halekas J, Stevens ML, Szabo A, Raouafi Net al., 2025,

    Parker Solar Probe Observations of a Highly Energetic and Asymmetric Reconnecting Heliospheric Current Sheet during Encounter 13

    , ASTROPHYSICAL JOURNAL, Vol: 986, ISSN: 0004-637X
  • Journal article
    Huang J, Larson DE, Ervin T, Liu M, Ortiz O, Martinovic MM, Huang Z, Chasapis A, Chu X, Alterman BL, Huang Z, Wei W, Verniero JL, Jian LK, Szabo A, Romeo O, Rahmati A, Livi R, Whittlesey P, Alnussirat ST, Kasper JC, Stevens M, Bale SDet al., 2025,

    The Temperature Anisotropy and Helium Abundance Features of Alfvénic Slow Solar Wind Observed by Parker Solar Probe, Helios, and Wind Missions

    , ASTROPHYSICAL JOURNAL LETTERS, Vol: 986, ISSN: 2041-8205
  • Journal article
    Dakeyo J-B, Demoulin P, Rouillard A, Maksimovic M, Chapiron A, Bale Set al., 2025,

    Generalized Two Thermal Regime Approach: Bipoly Fluid Modeling

    , ASTROPHYSICAL JOURNAL, Vol: 986, ISSN: 0004-637X
  • Journal article
    Seo G-Y, Min S-K, Lee D, Son S-W, Park C, Cha D-Het al., 2025,

    Hourly extreme rainfall projections over South Korea using convection permitting climate simulations

    , NPJ CLIMATE AND ATMOSPHERIC SCIENCE, Vol: 8, ISSN: 2397-3722
  • Journal article
    Grillakis M, Voulgarakis A, 2025,

    Diverse wildfire impacts on river flows across the globe

    , Communications Earth & Environment, Vol: 6, ISSN: 2662-4435

    Forest fires can significantly impact the hydrological regime of river basins, affecting short-term flood propensity and long-term water resource availability until vegetation is reestablished. While basin-level studies have extensively investigated these impacts, regional and global-scale assessments remain limited. Here we use a comprehensive global dataset of river discharge observations to systematically assess the hydrological response to wildfires for a range of hydrologically homogenous world regions and biomes. Our analysis reveals contrasting hydrological impacts by region, with high-latitude discharge ratios declining by 7.5% and 16% in the first and second year after wildfire, respectively, while Northern mid-latitude regions showing a marginal 3.3% median increase in discharge ratio the first-year post-fire. Sub-tropical and equatorial regions display negative and positive effects, respectively. We further discuss how potential ecological and hydroclimatic factors, along with human river and watershed management, shape these diverse hydrological responses per hydroclimatic region.
  • Journal article
    Zomerdijk-Russell S, Jasinski J, Masters A, 2025,

    Variation of model-predicted reconnection voltages applied to Uranus’ dayside magnetosphere

    , JGR: Space Physics, ISSN: 2169-9402

    Uranus provides a key missing piece for fundamentally understanding solar wind-magnetospheric interactions due to its location in the outer solar system. Whether the viscous-like interaction overtakes global magnetic reconnection as the dominant process at the magnetopauseof the outer planets remains unresolved. Here, we present theoretical predictions of dayside reconnection voltages applied to the Uranian system under different magnetospheric configurations to assess the effectiveness of global magnetic reconnection in the driving of Uranus’magnetosphere. We find the median model-predicted dayside reconnection voltage applied to Uranus’ magnetosphere is 22.4 kV. Over just one full planetary rotation, the reconnection voltages are found to vary by tens of kV under Uranus’ magnetospheric configuration during its solstice and equinox seasons with fixed solar wind conditions. However, we do not find a significant difference between average voltages at the different seasons, despite the large differences in magnetospheric configuration between solstice and equinox at Uranus. An increase from ~17 kV to ~31 kV in the modeled reconnection voltages is observed when the strength of the interplanetarymagnetic field is increased corresponding to expected conditions during solar maximum. Our results suggest that variability resulting from the planet’s diurnal rotation and changing solar wind conditions, are more important in controlling the reconnection voltages than seasonaldependencies.
  • Journal article
    Horner G, Gryspeerdt E, 2025,

    How does the lifetime of detrained cirrus impact the high-cloud radiative effect in the tropics?

    , Atmospheric Chemistry and Physics, Vol: 25, Pages: 5617-5631, ISSN: 1680-7316

    The lifetime of cirrus clouds from deep convection plays an important role in determining their overall cloud radiative effect (CRE). The net CRE of cirrus clouds from deep convection is close to zero over their whole lifetime. This CRE is the result of a near-cancellation of a large shortwave (SW) cooling and large longwave (LW) warming, such that small changes in cirrus properties have the potential to produce a significant net radiative effect. Changes in the atmospheric and sea surface temperature structure, along with changes in anthropogenic aerosol, have been hypothesised to impact the lifetime of detrained cirrus clouds, altering this radiative balance. Constraining the potential CRE response to changes in cirrus lifetime is therefore vital to understand the strength of these proposed climate forcings and feedbacks.This paper tracks the evolution of detrained cirrus clouds along trajectories from deep convection. The total cirrus CRE in the tropics is found to be warming, at 11.2 ± 0.4 W m−2. It is found that cirrus clouds along trajectories from oceanic origin convection have a warming CRE of 10.0 ± 0.4 W m−2. In contrast, cirrus clouds along trajectories from land convection have a warming of 15.9 ± 0.7 W m−2 throughout their lifetime. This contrast is predominantly due to differences in the diurnal cycle of the initial convection over land and ocean.A proposed extension to the lifetime of the detrained cirrus leads to changes in the total cirrus CRE in the tropics. In all cases, doubling the lifetime of the detrained cirrus leads to an increase in the total cirrus CRE of 0.6 ± 0.1 W m−2. Whilst there is uncertainty in the strength of mechanisms responsible for a change in cirrus lifetime, this work provides an important constraint on the impact that any potential lifetime extension may have.
  • Journal article
    Desai MI, Drake JF, Phan T, Yin Z, Swisdak M, Mccomas DJ, Bale SD, Rahmati A, Larson D, Matthaeus WH, Dayeh MA, Starkey MJ, Raouafi NE, Mitchell DG, Cohen CMS, Szalay JR, Giacalone J, Hill ME, Christian ER, Schwadron NA, McNutt Jr RL, Malandraki O, Whittlesey P, Livi R, Kasper JCet al., 2025,

    Magnetic Reconnection-driven Energization of Protons up to ∼400 keV at the Near-Sun Heliospheric Current Sheet

    , ASTROPHYSICAL JOURNAL LETTERS, Vol: 985, ISSN: 2041-8205

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