Results
- Showing results for:
- Reset all filters
Search results
-
Journal articleJensen EA, Gopalswamy N, Wilson LB, et al., 2023,
The Faraday Effect Tracker of Coronal and Heliospheric Structures (FETCH) instrument
, FRONTIERS IN ASTRONOMY AND SPACE SCIENCES, Vol: 10, ISSN: 2296-987X- Cite
- Citations: 6
-
Journal articleFroment C, Agapitov OV, Krasnoselskikh V, et al., 2023,
Whistler waves generated inside magnetic dips in the young solar wind: Observations of the search-coil magnetometer on board Parker Solar Probe
, ASTRONOMY & ASTROPHYSICS, Vol: 672, ISSN: 0004-6361- Cite
- Citations: 13
-
Journal articleGryspeerdt E, Povey AC, Grainger RG, et al., 2023,
Uncertainty in aerosol-cloud radiative forcing is driven by clean conditions
, Atmospheric Chemistry and Physics, Vol: 23, Pages: 4115-4122, ISSN: 1680-7316Atmospheric aerosols and their impact on cloud properties remain the largest uncertainty in the human forcing of theclimate system. By increasing the concentration of cloud droplets (Nd ), aerosols reduce droplet size and increase the reflectivity of clouds (a negative radiative forcing). Central to this climate impact is the susceptibility of cloud droplet number to aerosol (β ), the diversity of which explains much of the variation in the radiative forcing from aerosol-cloud interactions (RFaci) in global climate models. This has made measuring β a key target for developing observational constraints of the aerosol forcing. While the aerosol burden of the clean, pre-industrial atmosphere has been demonstrated as a key uncertainty for the aerosol forcing, here we show that the behaviour of clouds under these clean conditions is of equal importance for understanding the spread in radiative forcing estimates between models and observations. This means that the uncertainty in the aerosol impact on clouds is, counterintuitively, driven by situations with little aerosol. Discarding clean conditions produces a close agreement between different model and observational estimates of the cloud response to aerosol, but does not provide a strong constraint on the RFaci. This makes constraining aerosol behaviour in clean conditions an important goal for future observational studies.
-
Journal articleHuang J, Kasper JC, Larson DE, et al., 2023,
Parker Solar Probe Observations of High Plasma <i>β</i> Solar Wind from the Streamer Belt
, ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, Vol: 265, ISSN: 0067-0049- Cite
- Citations: 12
-
Journal articleKarbashewski S, Agapitov OV, Kim HY, et al., 2023,
Whistler Wave Observations by Parker Solar Probe During Encounter 1: Counter-propagating Whistlers Collocated with Magnetic Field Inhomogeneities and their Application to Electric Field Measurement Calibration
, ASTROPHYSICAL JOURNAL, Vol: 947, ISSN: 0004-637X- Cite
- Citations: 14
-
Journal articleSafrankova J, Nemecek Z, Nemec F, et al., 2023,
Evolution of Magnetic Field Fluctuations and Their Spectral Properties within the Heliosphere: Statistical Approach
, ASTROPHYSICAL JOURNAL LETTERS, Vol: 946, ISSN: 2041-8205- Cite
- Citations: 10
-
Journal articleSeo H, Oneill LW, Bourassa MA, et al., 2023,
Ocean Mesoscale and Frontal-Scale Ocean-Atmosphere Interactions and Influence on Large-Scale Climate: A Review
, JOURNAL OF CLIMATE, Vol: 36, Pages: 1981-2013, ISSN: 0894-8755- Cite
- Citations: 114
-
Journal articleShuster JR, Gershman DJ, Giles BL, et al., 2023,
Temporal, Spatial, and Velocity-Space Variations of Electron Phase Space Density Measurements at the Magnetopause
, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 128, ISSN: 2169-9380 -
Journal articleBadman ST, Riley P, Jones SI, et al., 2023,
Prediction and Verification of Parker Solar Probe Solar Wind Sources at 13.3 R<sub>⊙</sub>
, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 128, ISSN: 2169-9380- Cite
- Citations: 32
-
Journal articleWells C, Kasoar M, Bellouin N, et al., 2023,
Local and remote climate impacts of future African aerosol emissions
, Atmospheric Chemistry and Physics, Vol: 23, Pages: 3575-3593, ISSN: 1680-7316The potential future trend in African aerosol emissions is uncertain, with a large range found in future scenarios used to drive climate projections. The future climate impact of these emissions is therefore uncertain. Using the Shared Socioeconomic Pathway (SSP) scenarios, transient future experiments were performed with the UK Earth System Model (UKESM1) to investigate the effect of African emissions following the high emission SSP370 scenario as the rest of the world follows the more sustainable SSP119, relative to a global SSP119 control. This isolates the effect of Africa following a relatively more polluted future emissions pathway. Compared to SSP119, SSP370 projects higher non-biomass-burning (non-BB) aerosol emissions, but lower biomass burning emissions, over Africa. Increased shortwave (SW) absorption by black carbon aerosol leads to a global warming, but the reduction in the local incident surface radiation close to the emissions is larger, causing a local cooling effect. The local cooling persists even when including the higher African CO2 emissions under SSP370 than SSP119. The global warming is significantly higher by 0.07 K when including the non-BB aerosol increases and higher still (0.22 K) when including all aerosols and CO2. Precipitation also exhibits complex changes. Northward shifts in the Inter-tropical Convergence Zone (ITCZ) occur under relatively warm Northern Hemisphere land, and local rainfall is enhanced due to mid-tropospheric instability from black carbon absorption. These results highlight the importance of future African aerosol emissions for regional and global climate and the spatial complexity of this climate influence.
-
Journal articleDandouras I, Taylor MGGT, De Keyser J, et al., 2023,
Space plasma physics science opportunities for the lunar orbital platform - Gateway
, Frontiers in Astronomy and Space Sciences, Vol: 10, Pages: 1-30, ISSN: 2296-987XThe Lunar Orbital Platform - Gateway (LOP - Gateway, or simply Gateway) is a crewed platform that will be assembled and operated in the vicinity of the Moon by NASA and international partner organizations, including ESA, starting from the mid-2020s. It will offer new opportunities for fundamental and applied scientific research. The Moon is a unique location to study the deep space plasma environment. Moreover, the lunar surface and the surface-bounded exosphere are interacting with this environment, constituting a complex multi-scale interacting system. This paper examines the opportunities provided by externally mounted payloads on the Gateway in the field of space plasma physics, heliophysics and space weather, and also examines the impact of the space environment on an inhabited platform in the vicinity of the Moon. It then presents the conceptual design of a model payload, required to perform these space plasma measurements and observations. It results that the Gateway is very well-suited for space plasma physics research. It allows a series of scientific objectives with a multi-disciplinary dimension to be addressed.
-
Journal articleLai T-K, Toumi R, 2023,
Has there been a recent shallowing of tropical cyclones?
, Geophysical Research Letters, Vol: 50, Pages: 1-9, ISSN: 0094-8276Many aspects of tropical cyclone (TC) properties at the surface have been changing but any systematic vertical changes are unknown. Here, we document a recent trend of high thick clouds of TCs. The global inner-core high thick cloud fraction measured by satellite has decreased from 2002 to 2021 by about 10% per decade. The TC inner-core surface rain rate is also found to have decreased during the same period by a similar percentage. This suppression of high thick clouds and rain has been largest during the intensification phase of the strongest TCs. Hence, these two independent and consistent observations suggest that the TC inner-core convection has weakened and that TCs have become shallower recently at least. For this period, the lifetime maximum intensity of major TCs has not changed and this suggests an increased efficiency of the spin-up of TCs.
-
Journal articleBassett N, Rapetti D, Nhan BD, et al., 2023,
Constraining a Model of the Radio Sky below 6 MHz Using the Parker Solar Probe/FIELDS Instrument in Preparation for Upcoming Lunar-based Experiments
, ASTROPHYSICAL JOURNAL, Vol: 945, ISSN: 0004-637X- Cite
- Citations: 2
-
Journal articleRaouafi NE, Stenborg G, Seaton DB, et al., 2023,
Magnetic Reconnection as the Driver of the Solar Wind
, ASTROPHYSICAL JOURNAL, Vol: 945, ISSN: 0004-637X- Cite
- Citations: 103
-
Journal articleElsden T, Southwood DJ, 2023,
Modeling features of field line resonance observable by a single spacecraft at Saturn
, JGR: Space Physics, Vol: 128, Pages: 1-21, ISSN: 2169-9402The observations of Southwood et al. (2021, https://doi.org/10.1029/2020JA028473), using data from the Cassini magnetometer from the final (proximal) orbits of the mission at Saturn, show large scale azimuthally polarized magnetic signals are always present near periapsis. The signals were attributed to standing Alfvén waves excited on the magnetic shells planetward of the Saturn D-ring. The apparent absence of any systematic variation in frequency as the spacecraft crossed magnetic shells, implied that the signals were not simply locally excited standing Alfvén modes, but were pumped by coupling to global compressional eigenmodes excited in a cavity formed in the dayside magnetosphere. In this study, we use a numerical magnetohydrodynamic (MHD) model to test such theoretical explanations for the observations, by examining in detail the MHD wave coupling and large scale spatial structure of the signals. The modeling not only shows good agreement with the data but further provides new insight into features previously overlooked in the data. In particular, we show how the apparent frequency of a single spacecraft observation is affected by the phase variation present in a local field line resonance.
-
Journal articleArcher M, Hartinger MD, Rastatter L, et al., 2023,
Auroral, ionospheric and ground magnetic signatures of magnetopause surface modes
, Journal of Geophysical Research: Space Physics, Vol: 128, Pages: 1-25, ISSN: 2169-9380Surface waves on Earth's magnetopause have a controlling effect upon global magnetospheric dynamics. Since spacecraft provide sparse in situ observation points, remote sensing these modes using ground-based instruments in the polar regions is desirable. However, many open conceptual questions on the expected signatures remain. Therefore, we provide predictions of key qualitative features expected in auroral, ionospheric, and ground magnetic observations through both magnetohydrodynamic theory and a global coupled magnetosphere-ionosphere simulation of a magnetopause surface eigenmode. These show monochromatic oscillatory field-aligned currents (FACs), due to both the surface mode and its non-resonant Alfvén coupling, are present throughout the magnetosphere. The currents peak in amplitude at the equatorward edge of the magnetopause boundary layer, not the open-closed boundary as previously thought. They also exhibit slow poleward phase motion rather than being purely evanescent. We suggest the upward FAC perturbations may result in periodic auroral brightenings. In the ionosphere, convection vortices circulate the poleward moving FAC structures. Finally, surface mode signals are predicted in the ground magnetic field, with ionospheric Hall currents rotating perturbations by approximately (but not exactly) 90° compared to the magnetosphere. Thus typical dayside magnetopause surface modes should be strongest in the East-West ground magnetic field component. Overall, all ground-based signatures of the magnetopause surface mode are predicted to have the same frequency across L-shells, amplitudes that maximize near the magnetopause's equatorward edge, and larger latitudinal scales than for field line resonance. Implications in terms of ionospheric Joule heating and geomagnetically induced currents are discussed.
-
Journal articleBrandt PC, Provornikova E, Bale SD, et al., 2023,
Future Exploration of the Outer Heliosphere and Very Local Interstellar Medium by Interstellar Probe
, SPACE SCIENCE REVIEWS, Vol: 219, ISSN: 0038-6308- Cite
- Citations: 16
-
Journal articleSibeck DGG, Murphy KRR, Porter FS, et al., 2023,
Quantifying the global solar wind-magnetosphere interaction with the Solar-Terrestrial Observer for the Response of the Magnetosphere (STORM) mission concept
, FRONTIERS IN ASTRONOMY AND SPACE SCIENCES, Vol: 10, ISSN: 2296-987X- Cite
- Citations: 9
-
Journal articleKrasnoselskikh V, Tsurutani BT, Dudok de Wit T, et al., 2023,
ICARUS: in-situ studies of the solar corona beyond Parker Solar Probe and Solar Orbiter
, Experimental Astronomy, Vol: 54, Pages: 277-315, ISSN: 0922-6435The primary scientific goal of ICARUS (Investigation of Coronal AcceleRation and heating of solar wind Up to the Sun), a mother-daughter satellite mission, proposed in response to the ESA “Voyage 2050” Call, will be to determine how the magnetic field and plasma dynamics in the outer solar atmosphere give rise to the corona, the solar wind, and the entire heliosphere. Reaching this goal will be a Rosetta Stone step, with results that are broadly applicable within the fields of space plasma physics and astrophysics. Within ESA’s Cosmic Vision roadmap, these science goals address Theme 2: “How does the Solar System work?” by investigating basic processes occurring “From the Sun to the edge of the Solar System”. ICARUS will not only advance our understanding of the plasma environment around our Sun, but also of the numerous magnetically active stars with hot plasma coronae. ICARUS I will perform the first direct in situ measurements of electromagnetic fields, particle acceleration, wave activity, energy distribution, and flows directly in the regions in which the solar wind emerges from the coronal plasma. ICARUS I will have a perihelion altitude of 1 solar radius and will cross the region where the major energy deposition occurs. The polar orbit of ICARUS I will enable crossing the regions where both the fast and slow winds are generated. It will probe the local characteristics of the plasma and provide unique information about the physical processes involved in the creation of the solar wind. ICARUS II will observe this region using remote-sensing instruments, providing simultaneous, contextual information about regions crossed by ICARUS I and the solar atmosphere below as observed by solar telescopes. It will thus provide bridges for understanding the magnetic links between the heliosphere and the solar atmosphere. Such information is crucial to our understanding of the plasma physics and electrodynamics of the solar atmosph
-
Journal articleMcComas DJ, Sharma T, Christian ER, et al., 2023,
Parker Solar Probe Encounters the Leg of a Coronal Mass Ejection at 14 Solar Radii
, ASTROPHYSICAL JOURNAL, Vol: 943, ISSN: 0004-637X- Cite
- Citations: 12
-
Journal articleRaouafi NE, Matteini L, Squire J, et al., 2023,
Parker solar probe: four years of discoveries at solar cycle minimum
, Space Science Reviews, Vol: 219, Pages: 1-140, ISSN: 0038-6308Launched on 12 Aug. 2018, NASA’s Parker Solar Probe had completed 13 of its scheduled 24 orbits around the Sun by Nov. 2022. The mission’s primary science goal is to determine the structure and dynamics of the Sun’s coronal magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what processes accelerate energetic particles. Parker Solar Probe returned a treasure trove of science data that far exceeded quality, significance, and quantity expectations, leading to a significant number of discoveries reported in nearly 700 peer-reviewed publications. The first four years of the 7-year primary mission duration have been mostly during solar minimum conditions with few major solar events. Starting with orbit 8 (i.e., 28 Apr. 2021), Parker flew through the magnetically dominated corona, i.e., sub-Alfvénic solar wind, which is one of the mission’s primary objectives. In this paper, we present an overview of the scientific advances made mainly during the first four years of the Parker Solar Probe mission, which go well beyond the three science objectives that are: (1) Trace the flow of energy that heats and accelerates the solar corona and solar wind; (2) Determine the structure and dynamics of the plasma and magnetic fields at the sources of the solar wind; and (3) Explore mechanisms that accelerate and transport energetic particles.
-
Journal articleLiu YD, Ran H, Hu H, et al., 2023,
On the Generation and Evolution of Switchbacks and the Morphology of the Alfvenic Transition: Low Mach-number Boundary Layers
, ASTROPHYSICAL JOURNAL, Vol: 944, ISSN: 0004-637X- Cite
- Citations: 18
-
Journal articleShi C, Velli M, Lionello R, et al., 2023,
Proton and Electron Temperatures in the Solar Wind and Their Correlations with the Solar Wind Speed
, ASTROPHYSICAL JOURNAL, Vol: 944, ISSN: 0004-637X- Cite
- Citations: 17
-
Journal articleMoses JI, Brown ZL, Koskinen TT, et al., 2023,
Saturn’s atmospheric response to the large influx of ring material inferred from Cassini INMS measurements
, Icarus, Vol: 391, Pages: 1-40, ISSN: 0019-1035During the Grand Finale stage of the Cassini mission, organic-rich ring material was discovered to be flowing into Saturn’s equatorial upper atmosphere at a surprisingly large rate. Through a series of photochemical models, we have examined the consequences of this ring material on the chemistry of Saturn’s neutral and ionized atmosphere. We find that if a substantial fraction of this material enters the atmosphere as vapor or becomes vaporized as the solid ring particles ablate upon atmospheric entry, then the ring-derived vapor would strongly affect the composition of Saturn’s ionosphere and neutral stratosphere. Our surveys of Cassini infrared and ultraviolet remote-sensing data from the final few years of the mission, however, reveal none of these predicted chemical consequences. We therefore conclude that either (1) the inferred ring influx represents an anomalous, transient situation that was triggered by some recent dynamical event in the ring system that occurred a few months to a few tens of years before the 2017 end of the Cassini mission, or (2) a large fraction of the incoming material must have been entering the atmosphere as small dust particles less than 100 nm in radius, rather than as vapor or as large particles that are likely to ablate. Future observations or upper limits for stratospheric neutral species such as HCN, HCN, and CO at infrared wavelengths could shed light on the origin, timing, magnitude, and nature of a possible vapor-rich ring-inflow event.
-
Journal articleTrattner KJ, Fuselier SA, Schwartz SJ, et al., 2023,
Ion Acceleration at the Quasi-Parallel Shock: The Source Distributions of the Diffuse Ions
, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 128, ISSN: 2169-9380- Cite
- Citations: 2
-
Journal articlePhillips C, Bandyopadhyay R, McComas DJ, et al., 2023,
Association of intermittency with electron heating in the near-Sun solar wind
, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Vol: 519, Pages: L1-L4, ISSN: 0035-8711- Cite
- Citations: 5
-
Journal articleTrotta D, Hietala H, Horbury T, et al., 2023,
Multi-spacecraft observations of shocklets at an interplanetary shock
, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Vol: 520, Pages: 437-445, ISSN: 0035-8711- Cite
- Citations: 19
-
Journal articleZomerdijk-Russell S, Masters A, Korth H, et al., 2023,
Modelling the time-dependent magnetic fields that BepiColombo will use to probe down into Mercury’s mantle
, Geophysical Research Letters, Vol: 50, ISSN: 0094-8276External solar wind variability causes motion of the magnetopause and changes of this boundary's current structure, and the resulting inductive processes, may be exploited to determine the interior structure of magnetized planets. In preparation for the arrival of the BepiColombo spacecraft at Mercury, we here assess solar wind ram pressure forcing in this planet's environment, through analysis of data acquired by the Helios spacecraft, and the impact on the magnetopause's inducing field. These measurements suggest that BepiColombo will see highly unpredictable solar wind conditions and that the inducing field generated in response to variable solar wind ram pressure is non-uniform across the planet's surface. The inducing magnetic field spectrum, with frequencies in the range of ∼5.5 x10¯⁵ -1.5 x 10¯²Hz, suggests that the transfer functions derived from the two BepiColombo spacecraft could allow us to obtain a profile of conductivity through Mercury's crust and mantle.
-
Journal articleDe Marco R, Bruno R, Jagarlamudi VK, et al., 2023,
Innovative technique for separating proton core, proton beam, and alpha particles in solar wind 3D velocity distribution functions
, ASTRONOMY & ASTROPHYSICS, Vol: 669, ISSN: 0004-6361- Cite
- Citations: 13
-
Journal articleMaffei S, Eggington JWB, Livermore PW, et al., 2023,
Climatological predictions of the auroral zone locations driven by moderate and severe space weather events
, Scientific Reports, Vol: 13, Pages: 1-11, ISSN: 2045-2322Auroral zones are regions where, in an average sense, aurorae due to solar activity are most likely spotted. Their shape and, similarly, the geographical locations most vulnerable to extreme space weather events (which we term ‘danger zones’) are modulated by Earth’s time-dependent internal magnetic field whose structure changes on yearly to decadal timescales. Strategies for mitigating ground-based space weather impacts over the next few decades can benefit from accurate forecasts of this evolution. Existing auroral zone forecasts use simplified assumptions of geomagnetic field variations. By harnessing the capability of modern geomagnetic field forecasts based on the dynamics of Earth’s core we estimate the evolution of the auroral zones and of the danger zones over the next 50 years. Our results predict that space-weather related risk will not change significantly in Europe, Australia and New Zealand. Mid-to-high latitude cities such as Edinburgh, Copenhagen and Dunedin will remain in high-risk regions. However, northward change of the auroral and danger zones over North America will likely cause urban centres such as Edmonton and Labrador City to be exposed by 2070 to the potential impact of severe solar activity.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.