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Journal articleGoodwin P, Williams RG, Ceppi P, et al., 2025,
Climate feedbacks derived from spatial gradients in recent climatology
, Journal of Geophysical Research (JGR): Atmospheres, Vol: 130, ISSN: 2169-897XClimate feedbacks, including Planck, surface albedo, water vapor-lapse rate (WVLR) and cloud feedbacks, determine how much surface temperatures will eventually warm to balance anthropogenic radiative forcing. Climate feedbacks remain difficult to constrain directly from temporal variation in observed surface warming and radiation budgets due to the pattern effect and low signal-to-noise ratio, with only order 1°C historic rise in surface temperatures and high uncertainty in aerosol radiative forcing. This study presents a new method to analyze climate feedbacks from observations by empirically fitting simplified reduced-physics relations for outgoing radiation at the top of the atmosphere (TOA) to observed spatial variation in climate properties and radiation budgets. Spatial variations in TOA outgoing radiation are dominated by the dependence on surface temperature: around 91% of the spatial variation in clear sky albedo, and 77% of spatial variation in clear sky TOA outgoing longwave radiation, is functionally explained by variation in surface temperatures. These simplified and observationally constrained relations are then differentiated with respect to spatial contrasts in surface temperature to reveal the Planck, fixed-cloud albedo (𝜆albedo) and WVLR (𝜆WVLR) climate feedbacks spatially for both clear sky and all sky conditions. The resulting global all sky climate feedback values are 𝜆WVLR = 1.28 (1.13–1.45 at 66%) Wm⁻²K⁻¹, and 𝜆albedo = 0.64 (0.53–0.74) Wm−2 for the period 2003–2023, reducing to 0.35 (0.29–0.41) Wm⁻²K⁻¹ under 4°C warming after cryosphere retreat. Our findings agree well with complex Earth system model evaluations based on temporal climate perturbations, and our approach is complementary.
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Journal articleKartavykh Y, Rodriguez-Garcia L, Heber B, et 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 articleHuang J, Larson DE, Ervin T, et 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- Cite
- Citations: 3
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Journal articlePhan TD, Romeo OM, Drake JF, et 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 articleDakeyo J-B, Demoulin P, Rouillard A, et al., 2025,
Generalized Two Thermal Regime Approach: Bipoly Fluid Modeling
, ASTROPHYSICAL JOURNAL, Vol: 986, ISSN: 0004-637X -
Journal articleHamilton CW, Mcewen AS, Keszthelyi L, et al., 2025,
Comparing NASA discovery and new frontiers class mission concepts for the Io volcano observer
, The Planetary Science Journal, Vol: 6, ISSN: 2632-3338Jupiter’s moon Io is a highly compelling target for future exploration that offers critical insight into tidal dissipation processes and the geology of high heat flux worlds, including primitive planetary bodies, such as the early Earth, that are shaped by enhanced rates of volcanism. Io is important for understanding the development of volcanogenic atmospheres and mass exchange within the Jupiter system. However, fundamental questions remain about the state of Io’s interior, surface, and atmosphere, as well as its role in the evolution of the Galilean satellites. The Io Volcano Observer (IVO) would advance answers to these questions by addressing three key goals: (A) determine how and where tidal heat is generated inside Io, (B) understand how tidal heat is transported to the surface of Io, and (C) understand how Io is evolving. IVO was selected for Phase A study through the NASA Discovery program in 2020, and, in anticipation of the next New Frontiers (NF) opportunity, an enhanced IVO-NF mission concept would increase the Baseline mission from 10 flybys to 20, with an improved radiation design; employ a Ka-band communication system to double IVO’s total data downlink; add a wide-angle camera for color and stereo mapping; add a dust mass spectrometer; and lower the altitude of later flybys to enable new science. This study compares the architecture, instrument suite, and science objectives for Discovery (IVO) and NF (IVO-NF) missions to Io. IVO can achieve outstanding science results at the Discovery level, but we advocate for continued prioritization of Io for NF.
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Journal articleSeo G-Y, Min S-K, Lee D, et 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 articleGrillakis M, Voulgarakis A, 2025,
Diverse wildfire impacts on river flows across the globe
, Communications Earth & Environment, Vol: 6, ISSN: 2662-4435Forest 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.
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Journal articleDesai MI, Drake JF, Phan T, et 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- Cite
- Citations: 2
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Journal articleHorner 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: 1680-7316The 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.
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Journal articleMauritsen T, Tsushima Y, Meyssignac B, et al., 2025,
Earth's energy imbalance more than doubled in recent decades
, AGU Advances, Vol: 6, ISSN: 2576-604XGlobal warming results from anthropogenic greenhouse gas emissions which upset the delicate balance between the incoming sunlight, and the reflected and emitted radiation from Earth. The imbalance leads to energy accumulation in the atmosphere, oceans and land, and melting of the cryosphere, resulting in increasing temperatures, rising sea levels, and more extreme weather around the globe. Despite the fundamental role of the energy imbalance in regulating the climate system, as known to humanity for more than two centuries, our capacity to observe it is rapidly deteriorating as satellites are being decommissioned.
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Journal articleZomerdijk-Russell S, Jasinski J, Masters A, 2025,
Variation of model-predicted reconnection voltages applied to Uranus’ dayside magnetosphere
, JGR: Space Physics, Vol: 130, ISSN: 2169-9402Uranus 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 magnetopause of 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 to ∼31 kV in the modeled reconnection voltages is observed when the strength of the interplanetary magnetic 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 seasonal dependencies.
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Journal articleKim K, Edberg NJT, Modolo R, et al., 2025,
Electron Structures in Titan's Induced Magnetosphere and Low-Frequency Wave Activity
, JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS, Vol: 130, ISSN: 2169-9097 -
Journal articleLozinski AR, Kellerman AC, Bortnik J, et al., 2025,
Modeling the Internal Redistribution of Earth's Proton Radiation Belt by Interplanetary Shocks
, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 130, ISSN: 2169-9380 -
Journal articleColomban L, Agapitov OV, Krasnoselskikh V, et al., 2025,
Polarization Properties of Whistler Waves From the First 17 Parker Solar Probe Encounters
, GEOPHYSICAL RESEARCH LETTERS, Vol: 52, ISSN: 0094-8276 -
Journal articleBowen TA, Dunn CI, Mallet A, et al., 2025,
Nonlinear interactions in spherically polarized Alfvénic turbulence
, The Astrophysical Journal (ApJ), Vol: 985, ISSN: 0004-637XTurbulent magnetic field fluctuations observed in the solar wind often maintain a constant-magnitude magnetic field accompanied by spherically polarized velocity fluctuations; these signatures are characteristic of large-amplitude Alfvén waves. Nonlinear energy transfer in Alfvénic turbulence is typically considered in the small-amplitude limit where the constant-magnitude condition may be neglected; in contrast, nonlinear energy transfer of large-amplitude fluctuations remains relatively unstudied. We develop a method to analyze large-amplitude turbulence through studying fluctuations as constant-magnitude rotations in the de Hoffmann–Teller frame, in which the convected electric field of the fluctuations vanishes such that the frame and fluctuations are copropagating. Our analysis reveals signatures of large-amplitude effects deep into the inertial range. While the dominant fluctuations are consistent with spherically polarized large-amplitude Alfvén waves, the subdominant fluctuations are relatively compressible. Signatures of nonlinear interaction between the large-amplitude spherically polarized mode with the subdominant population reveal highly aligned transverse components. In many theoretical models of Alfvénic turbulence, alignment is thought to reduce nonlinearity; our observations suggest that the observed alignment is sufficient to either reduce shear nonlinearity such that non-Alfvénic interactions may be responsible for energy transfer in spherically polarized states, or alternatively that counterpropagating fluctuations maintain anomalous coherence, a predicted signature of reflection-driven turbulence.
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Journal articleAlnussirat ST, Larson DE, Livi R, et al., 2025,
Impulsive Solar Flares in the Parker Solar Probe Era. I. Low-energy Electron, Proton, and Alpha Beams
, ASTROPHYSICAL JOURNAL, Vol: 985, ISSN: 0004-637X -
Journal articleLi F, Lawrence DM, Rogers BM, et al., 2025,
The Fire Modeling Intercomparison Project (FireMIP) for CMIP7
, Geoscientific Model Development, Vol: 19, Pages: 3989-4007, ISSN: 1991-959XFire is a global phenomenon and a key Earth system process. Extreme fire events have increased in recent years, and fire frequency and intensity are projected to rise across most regions and biomes, posing substantial challenges for ecosystems, the carbon cycle, and society. The Fire Model Intercomparison Project (FireMIP), launched in 2014, has advanced global fire modeling in Dynamic Global Vegetation Models (DGVMs) and improved understanding of fire's local and direct drivers and its local impacts on vegetation and land carbon budgets through land offline simulations (i.e., uncoupled from the atmosphere). We now bring FireMIP into Coupled Model Intercomparison Project Phase 7 (CMIP7) to: (1) evaluate fire simulations in state-of-the-art fully coupled Earth system models (ESMs); (2) assess fire regime changes in the past, present, and future, and identify their primary natural and anthropogenic forcings and causal pathways within the Earth system, including the associated uncertainties; and (3) quantify the impacts of fires and fire changes on climate, ecosystems, and society across Earth system components, regions, and timescales, and elucidate the underlying mechanisms. FireMIP in CMIP7 will advance the fire and fire-related modeling in fully coupled ESMs, and provide a quantitative, comprehensive, and process-based understanding of fire's role in the Earth system by using models that incorporate critical climate feedbacks and CMIP7 multi-model, multi-initial-condition, and multi-scenario ensemble. This protocol paper presents the motivation, scientific questions, experimental design and rationale, model inputs and outputs, and recommended analysis framework for FireMIP in CMIP7, providing guidance to Earth system modeling teams conductin
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Journal articleCuesta ME, Livadiotis G, Mccomas DJ, et al., 2025,
Transfer of Entropy between the Magnetic Field and Solar Energetic Particles during an Interplanetary Coronal Mass Ejection
, ASTROPHYSICAL JOURNAL LETTERS, Vol: 984, ISSN: 2041-8205- Cite
- Citations: 2
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Journal articleShen MM, Szalay JR, Pokorny P, et al., 2025,
Diverse Dust Populations in the Near-Sun Environment Characterized by PSP/IS⊙IS
, ASTROPHYSICAL JOURNAL, Vol: 984, ISSN: 0004-637X- Cite
- Citations: 1
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Journal articleVallim D, Grillakis M, Manoudakis S, et al., 2025,
Stakeholder Engagement Drivers: Insights from an Information System Innovation Project Supporting Wildfire Evacuation in Greece
, Proceedings of the International Iscram ConferenceThe Samaria Gorge, a tourist destination in Crete, faces wildfire risk due to its dense forest, topography, number of visitors, and climate. As part of a H2020 project, the Gorge serves as a testing pilot for a new wildfire management platform that integrates technologies to improve fire detection, risk assessment, and resource allocation during a wildfire evacuation. A central component of the project is a multi-stakeholder network, which supports both governance and acceptance of solutions. To understand the drivers of network formation, we used a Social Network Analysis and Exponential Random Graphs Model approaches to identify the drivers of stakeholder collaboration. Our findings indicate that sectoral and wildfire management focus phase are factors driving connections, while the working in intersecting jurisdictions is not. The results highlight the challenges of multi-stakeholder collaboration, suggesting that policy frameworks and information systems need to develop specific mechanisms to encourage stakeholders to bridge collaborative gaps.
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Journal articlePerkins O, Kasoar M, Voulgarakis A, et al., 2025,
The spatial distribution and temporal drivers of changing global fire regimes: a coupled socio-ecological modeling approach
, Earth's Future, Vol: 13, ISSN: 2328-4277The limited capacity of fire-enabled vegetation models to represent human influences on fire regimes is a fundamental challenge in fire science. This limitation places a major constraint on our capacity to understand how vegetation fire may change under future scenarios of climate change and socio-economic development. Here, we address this challenge by presenting a novel integration of two process-based models. The first is the Wildfire Human Agency Model (WHAM!), which draws on agent-based approaches to represent anthropogenic fire use and management. The second is JULES-INFERNO, a fire-enabled dynamic global vegetation model, which takes a physically grounded approach to the representation of vegetation-fire dynamics. The combined model enables a coupled socio-ecological simulation of historical burned area. We calibrate the combined model using GFED5 burned area data and perform an independent evaluation using MODIS-based fire radiative power observations. Results suggest that as much as half of all global burned area is generated by managed anthropogenic fires—typically small fires that are lit for, and then spread according to, land user objectives. Furthermore, we demonstrate that including representation of managed anthropogenic fires in a coupled socio-ecological simulation improves understanding of the drivers of unmanaged wildfires. For example, we show how vegetation flammability and landscape fragmentation control inter-annual variability and longer-term change in unmanaged fires. Overall, findings presented here indicate that both socio-economic and climate change will be vital in determining the future trajectory of fire on Earth.
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Journal articleBeggan CD, Eastwood JP, Eggington JWB, et al., 2025,
Implementing an operational cloud‐based now‐ and forecasting system for space weather ground effects in the UK
, Space Weather, Vol: 23, ISSN: 1539-4956The enhanced variation of the magnetic field during severe to extreme geomagnetic storms induces a large geoelectric field in the subsurface. Grounded infrastructure can be susceptible to geomagnetically induced currents (GICs) during these events. Modeling the effect in real-time and forecasting the magnitude of GICs are important for allowing operators of critical infrastructure to make informed decisions on potential impacts. As part of the UK-funded Space Weather Innovation, Measurement, Modeling and Risk (SWIMMR) program, we implemented nine research-level models into operational codes capable of running consistently and robustly to produce estimates of GICs in the Great Britain high voltage power transmission network, the high pressure gas pipeline network and the railway network. To improve magnetic coverage and geoelectric field modeling accuracy, three new variometer sites were installed in the UK and a 3 year campaign of magnetotelluric measurements at 53 sites was undertaken. The models rely on real-time ground observatory data and solar wind data from satellites at the L1 Lagrange point. A mixture of empirical machine learning and numerical magnetohydrodynamic models are used for forecasting. In addition to nowcast capabilities, contextual information on the likelihood of substorms, sudden commencements and large rates of change of the magnetic field were developed. The final nowcast and forecast codes were implemented in a cloud-based environment using modern software tools and practices. We describe the process to move from research to operations (R2O).
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Journal articleNair R, Halekas JS, Cattell C, et al., 2025,
Suprathermal Electron Scattering by Narrowband Whistler Waves and Broadband Electrostatic Waves: Parker Solar Probe Observations
, ASTROPHYSICAL JOURNAL, Vol: 984, ISSN: 0004-637X -
Journal articleEastwood J, Brown P, Oddy T, et al., 2025,
In flight performance of the MAGIC magnetoresistive magnetometer on the RadCube CubeSat
, Space Science Reviews, Vol: 221, ISSN: 0038-6308In studying space physics, planetary science, and space weather, space-based in situ measurements of the magnetic field are fundamental to understanding underlying physical processes, as well as providing context for other observations. Whilst in many cases instrument design is not severely constrained by the available resource envelope, there are many applications, particularly when using new generations of spacecraft platforms such as CubeSats, that require very low resource sensors. In this context we review the design, development, construction, and flight of the highly miniaturised MAGIC (MAGnetometer from Imperial College) instrument on the RadCube Technology Demonstration CubeSat. MAGIC consists of a boom-mounted (outboard) Anisotropic Magneto-Resistive (AMR) vector sensor connected by harness to a single electronics card inside RadCube. A second inboard AMR vector sensor is mounted on the electronics card. RadCube launched on 17 August 2021 to a sun-synchronous low-Earth polar orbit, with the main mission lasting until April 2022. Routine operations were subsequently extended to the end of 2022, with further special operations in 2023 and 2024 before re-entry on 20 August 2024. Here we review RadCube observations made over more than two years in orbit. Key results from MAGIC on RadCube include meeting ESA space weather magnetic field measurement requirements with both the outboard and inboard sensor, as well as detection of field aligned current signatures at high latitude.
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Journal articleMackie A, Byrne MP, Van de Koot EK, et al., 2025,
Circulation and Cloud Responses to Patterned SST Warming
, Geophysical Research Letters, Vol: 52, ISSN: 0094-8276The climatological atmospheric circulation is key to establishing the tropical “pattern effect”, whereby cloud feedbacks induced by sea surface temperature (SST) warming depend on the spatial structure of that warming. But how patterned warming-induced circulation changes affect cloud responses is less clear. Here we use idealized simulations with prescribed SST perturbations to understand the contributions to changes in tropical-mean cloud radiative effects (CRE) from different circulation regimes. We develop a novel framework based on moist static energy to understand the circulation response, targeting in particular the bulk circulation metric of ascent fraction. Warming concentrated in regions of ascent leads to a strong “upped-ante” effect and spatial contraction of the ascending region. Our framework reveals substantial contributions to tropical-mean CRE changes not only from traditional “pattern effect” regimes, but also from the intensification of convection in ascent regions as well as a smaller contribution from cloud changes in convective margins.
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Journal articleWilson Kemsley S, Nowack P, Ceppi P, 2025,
Climate models underestimate global decreases in high‐cloud amount with warming
, Geophysical Research Letters, Vol: 52, ISSN: 0094-8276Cloud feedback has prevailed as a leading source of uncertainty in climate model projections under increasing atmospheric carbon dioxide. Cloud-controlling factor (CCF) analysis is an approach used to observationally constrain cloud feedback, and subsequently the climate sensitivity. Although high clouds contribute significantly toward uncertainty, they have received comparatively little attention in CCF and other observational analyses. Here we use CCF analysis for the first time to constrain the high-cloud radiative feedback, focusing on the cloud amount component owing to its dominant contribution to uncertainty in high-cloud feedback. Globally, observations indicate larger decreases in high cloudiness than state-of-the-art climate models suggest. In fact, half of the 16 models considered here predict radiative feedbacks inconsistent with observations, likely due to misrepresenting the stability iris mechanism. Despite the suggested strong high-cloud amount decreases with warming, observations point toward a near-neutral net high-cloud amount radiative feedback, owing to almost canceling longwave and shortwave contributions.
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Journal articleDing M, 2025,
Challenges in Atomic Spectroscopy of Low-Ionisation-Stage Heavy Elements for Astrophysics
, ATOMS, Vol: 13 -
Conference paperBeth A, Galand M, Modolo R, et al., 2025,
Ionospheric environment of Ganymede during the Galileo flybys
, EGU General Assembly, Publisher: EGUThe Galileo spacecraft flew by Ganymede, down to 0.1 RG from the surface for the closest, six times giving us insight into its plasma environment. Its ionosphere, made of ions born from the ionisation of neutrals present in Ganymede’s exosphere, represents the bulk of the plasma near the moon around closest approach. As it has been revealed by Galileo and Juno, near closest approach the ion population is dominated by low-energy ions from the water ion group (O+, HO+, H2O+) and O2+. However, little is known about their density, spatial distribution, and effect on the surface weathering of the moon itself. Galileo G2 flyby has been extensively studied. Based on a comparison between observations and 3D test-particle simulations, Carnielli et al. (2020a and 2020b) confirmed the ion composition (debated at the time), highlighted the inconsistency between the assumed exospheric densities and the observed ionospheric densities, and derived the contribution of ionospheric ions as an exospheric source. However, other flybys of Ganymede are also available (e.g. G1, G7, G8, G28, and G29) providing in-situ measurements at different phases of Ganymede around Jupiter or jovian magnetospheric conditions at the moon. We extend the original study by Carnielli et al. to other flybys, and compare our modelled ion moments (ion number density, velocity, and energy distribution) with Galileo in-situ data. We discuss our results and contrast them with those obtained for the G2 flyby.
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Journal articleKim H, Kang SM, Pendergrass AG, et al., 2025,
Higher precipitation in East Asia and western United States expected with future Southern Ocean warming
, Nature Geoscience, Vol: 18, Pages: 313-321, ISSN: 1752-0894Precipitation over East Asia and the western United States is projected to increase as a result of global warming, although substantial uncertainties persist regarding the magnitude. A key factor driving these uncertainties is the tropical surface warming pattern, yet the mechanisms behind both this warming pattern and the resulting regional precipitation changes remain elusive. Here we use a set of climate model experiments to argue that these changes are partly driven by global teleconnection from the Southern Ocean, which rapidly absorbs anthropogenic heat but releases it with a delay of decades to a century. We show that the delayed Southern Ocean warming contributes to broad tropical ocean warming with an El Niño-like pattern, enhancing precipitation during summer in East Asia and winter in the western United States. The atmospheric teleconnections from the tropical ocean link the Southern Ocean warming to the Northern Hemisphere regional wetting. Southern Hemisphere low clouds are a key regulator of this teleconnection, partly explaining the projected uncertainty of regional precipitation. The documented teleconnection has practical implications: even if climate mitigation reduces carbon dioxide levels, the delayed Southern Ocean warming will sustain a wetter East Asia and western United States for decades to centuries.
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