Publications

Journal article

Kilpua EKJ, Turner DL, Jaynes AN, Hietala H, Koskinen HEJ, Osmane A, Palmroth M, Pulkkinen T, Vainio R, Baker D, Claudepierre SGet al., 2019,

Outer Van Allen Radiation Belt Response to Interacting Interplanetary Coronal Mass Ejectionsy

, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 124, Pages: 1927-1947, ISSN: 2169-9380

Journal article

Graven H, Hocking T, Zazzeri G, 2019,

Detection of fossil and biogenic methane at regional scales using atmospheric radiocarbon

, Earth's Future, Vol: 7, Pages: 283-299, ISSN: 2328-4277

Regional emissions of methane and their attribution to a variety of sources presently have large uncertainties. Measurements of radiocarbon (14C) in methane (CH4) may provide a method for identifying regional CH4 emissions from fossil versus biogenic sources because adding 14C‐free fossil carbon reduces the 14C/C ratio (Δ14CH4) in atmospheric CH4 much more than biogenic carbon does. We describe an approach for estimating fossil and biogenic CH4 at regional scales using atmospheric Δ14CH4 observations. As a case study to demonstrate expected Δ14CH4 and Δ14CH4‐CH4 relationships, we simulate and compare Δ14CH4 at a network of sites in California using two gridded CH4 emissions estimates (Emissions Database for Global Atmospheric Research, EDGAR, and Gridded Environmental Protection Agency, GEPA) and the CarbonTracker‐Lagrange model for 2014, and for 2030 under business‐as‐usual and mitigation scenarios. The fossil fraction of CH4 (F) is closely linked with the simulated Δ14CH4‐CH4 slope and differences of 2–21% in median F are found for EDGAR versus GEPA in 2014, and 7–10% for business‐as‐usual and mitigation scenarios in 2030. Differences of 10% in F for >200 ppb of added CH4 produce differences of >10‰ in Δ14CH4, which are likely detectable from regular observations. Nuclear power plant 14CH4 emissions generally have small simulated median influences on Δ14CH4 (0–7‰), but under certain atmospheric conditions they can be much stronger (>30‰) suggesting they must be considered in applications of Δ14CH4 in California. This study suggests that atmospheric Δ14CH4 measurements could provide powerful constraints on regional CH4 emissions, complementary to other monitoring techniques.

Journal article

Goodrich KA, Ergun R, Schwartz SJ, Wilson LB, Johlander A, Newman D, Wilder FD, Holmes J, Burch J, Torbert R, Khotyaintsev Y, Lindqvist P-A, Strangeway R, Gershman D, Giles Bet al., 2019,

Impulsively Reflected Ions: A Plausible Mechanism for Ion Acoustic Wave Growth in Collisionless Shocks

, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 124, Pages: 1855-1865, ISSN: 2169-9380

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Citations: 15

Journal article

Stansby D, Perrone D, Matteini L, Horbury T, Salem Cet al., 2019,

Alpha particle thermodynamics in the inner heliosphere fast solar wind

, Astronomy and Astrophysics, Vol: 623, ISSN: 0004-6361

Context. Plasma processes occurring in the corona and solar wind can be probed by studying the thermodynamic properties ofdifferent ion species. However, most in-situ observations of positive ions in the solar wind are taken at 1 AU, where information ontheir solar source properties may have been irreversibly erased.Aims. In this study we aimed to use the properties of alpha particles at heliocentric distances between 0.3 and 1 AU to study plasmaprocesses occurring at the points of observation, and to infer processes occurring inside 0.3 AU by comparing our results to previousremote sensing observations of the plasma closer to the Sun.Methods. We reprocessed the original Helios positive ion distribution functions, isolated the alpha particle population, and computedthe alpha particle number density, velocity, and magnetic field perpendicular and parallel temperatures. We then investigated the radialvariation of alpha particle temperatures in fast solar wind observed between 0.3 and 1 AU.Results. Between 0.3 and 1 AU alpha particles are heated in the magnetic field perpendicular direction, and cooled in the magneticfield parallel direction. Alpha particle evolution is bounded by the alpha firehose instability threshold, which provides one possiblemechanism to explain the observed parallel cooling and perpendicular heating. Closer to the Sun our observations suggest that thealpha particles undergo heating in the perpendicular direction, whilst the large magnetic field parallel temperatures observed at 0.3 AUmay be due to the combined effect of double adiabatic expansion and alpha particle deceleration inside 0.3 AU.

Journal article

Øieroset M, Phan TD, Drake JF, Eastwood JP, Fuselier SA, Strangeway RJ, Haggerty C, Shay MA, Oka M, Wang S, Chen L-J, Kacem I, Lavraud B, Angelopoulos V, Burch JL, Torbert RB, Ergun RE, Khotyaintsev Y, Lindqvist PA, Gershman DJ, Giles BL, Pollock C, Moore TE, Russell CT, Saito Y, Avanov LA, Paterson Wet al., 2019,

Reconnection with magnetic flux pileup at the interface of converging jets at the magnetopause

, Geophysical Research Letters, Vol: 46, Pages: 1937-1946, ISSN: 0094-8276

We report Magnetospheric Multiscale observations of reconnection in a thin current sheet at the interface of interlinked flux tubes carried by converging reconnection jets at Earth's magnetopause. The ion skin depth‐scale width of the interface current sheet and the non‐frozen‐in ions indicate that Magnetospheric Multiscale crossed the reconnection layer near the X‐line, through the ion diffusion region. Significant pileup of the reconnecting component of the magnetic field in this and three other events on approach to the interface current sheet was accompanied by an increase in magnetic shear and decrease in Δβ, leading to conditions favorable for reconnection at the interface current sheet. The pileup also led to enhanced available magnetic energy per particle and strong electron heating. The observations shed light on the evolution and energy release in 3‐D systems with multiple reconnection sites.

Journal article

Dimmock AP, Russell CT, Sagdeev RZ, Krasnoselskikh V, Walker SN, Carr C, Dandouras I, Escoubet CP, Ganushkina N, Gedalin M, Khotyaintsev YV, Aryan H, Pulkkinen TI, Balikhin MAet al., 2019,

Direct evidence of nonstationary collisionless shocks in space plasmas

, Science Advances, Vol: 5, ISSN: 2375-2548

Collisionless shocks are ubiquitous throughout the universe: around stars, supernova remnants, active galactic nuclei, binary systems, comets, and planets. Key information is carried by electromagnetic emissions from particles accelerated by high Mach number collisionless shocks. These shocks are intrinsically nonstationary, and the characteristic physical scales responsible for particle acceleration remain unknown. Quantifying these scales is crucial, as it affects the fundamental process of redistributing upstream plasma kinetic energy into other degrees of freedom-particularly electron thermalization. Direct in situ measurements of nonstationary shock dynamics have not been reported. Thus, the model that best describes this process has remained unknown. Here, we present direct evidence demonstrating that the transition to nonstationarity is associated with electron-scale field structures inside the shock ramp.

Journal article

Dubois D, Carrasco N, Bourgalais J, Vettier L, Desai RT, Wellbrock A, Coates AJet al., 2019,

Nitrogen-containing Anions and Tholin Growth in Titan's Ionosphere: Implications for Cassini CAPS-ELS Observations

, ASTROPHYSICAL JOURNAL LETTERS, Vol: 872, ISSN: 2041-8205

Journal article

Provan G, Cowley SWH, Bunce EJ, Bradley TJ, Hunt GJ, Cao H, Dougherty MKet al., 2019,

Variability of Intra-D Ring Azimuthal Magnetic Field Profiles Observed on Cassini's Proximal Periapsis Passes

, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 124, Pages: 379-404, ISSN: 2169-9380

Journal article

Gingell I, Schwartz SJ, Eastwood JP, Burch JL, Ergun RE, Fuselier S, Gershman DJ, Giles BL, Khotyaintsev Y, Lavraud B, Lindqvist P-A, Paterson WR, Phan TD, Russell CT, Stawarz JE, Strangeway RJ, Torbert RB, Wilder Fet al., 2019,

Observations of magnetic reconnection in the ransition region of quasi-parallel hocks

, Geophysical Research Letters, Vol: 46, Pages: 1177-1184, ISSN: 0094-8276

Using observations of Earth's bow shock by the Magnetospheric Multiscale mission, we show for the first time that active magnetic reconnection is occurring at current sheets embedded within the quasi‐parallel shock's transition layer. We observe an electron jet and heating but no ion response, suggesting we have observed an electron‐only mode. The lack of ion response is consistent with simulations showing reconnection onset on sub‐ion time scales. We also discuss the impact of electron heating in shocks via reconnection.

Journal article

Ball WT, Rozanov EV, Alsing J, Marsh DR, Tummon F, Mortlock DJ, Kinnison D, Haigh JDet al., 2019,

The upper stratospheric solar cycle ozone response

, Geophysical Research Letters, Vol: 46, Pages: 1831-1841, ISSN: 0094-8276

The solar cycle (SC) stratospheric ozone response is thought to influence surface weather and climate. To understand the chain of processes and ensure climate models adequately represent them, it is important to detect and quantify an accurate SC ozone response from observations. Chemistry climate models (CCMs) and observations display a range of upper stratosphere (1–10 hPa) zonally averaged spatial responses; this and the recommended data set for comparison remains disputed. Recent data-merging advancements have led to more robust observational data. Using these data, we show that the observed SC signal exhibits an upper stratosphere U-shaped spatial structure with lobes emanating from the tropics (5–10 hPa) to high altitudes at midlatitudes (1–3 hPa). We confirm this using two independent chemistry climate models in specified dynamics mode and an idealized timeslice experiment. We recommend the BASIC v2 ozone composite to best represent historical upper stratospheric solar variability, and that those based on SBUV alone should not be used.

Journal article

Archer MO, Hietala H, Hartinger MD, Plaschke F, Angelopoulos Vet al., 2019,

Direct observations of a surface eigenmode of the dayside magnetopause

, Nature Communications, Vol: 10, ISSN: 2041-1723

The abrupt boundary between a magnetosphere and the surrounding plasma, the magnetopause, has long been known to support surface waves. It was proposed that impulses acting on the boundary might lead to a trapping of these waves on the dayside by the ionosphere, resulting in a standing wave or eigenmode of the magnetopause surface. No direct observational evidence of this has been found to date and searches for indirect evidence have proved inconclusive, leading to speculation that this mechanism might not occur. By using fortuitous multipoint spacecraft observations during a rare isolated fast plasma jet impinging on the boundary, here we show that the resulting magnetopause motion and magnetospheric ultra-low frequency waves at well-defined frequencies are in agreement with and can only be explained by the magnetopause surface eigenmode. We therefore show through direct observations that this mechanism, which should impact upon the magnetospheric system globally, does in fact occur.

Journal article

Ferri F, Karatekin O, Lewis SR, Forget F, Aboudan A, Colombatti G, Bettanini C, Debei S, Van Hove B, Dehant V, Harri A-M, Leese M, Makinen T, Millour E, Muller-Wodarg I, Ori GG, Pacifici A, Paris S, Patel M, Schoenenberger M, Herath J, Siili T, Spiga A, Tokano T, Towner M, Withers P, Asmar S, Plettemeier Det al., 2019,

ExoMars Atmospheric Mars Entry and Landing Investigations and Analysis (AMELIA)

, SPACE SCIENCE REVIEWS, Vol: 215, ISSN: 0038-6308

Journal article

Vasko IY, Krasnoselskikh V, Tong Y, Bale SD, Bonnell W, Mozer FSet al., 2019,

Whistler Fan Instability Driven by Strahl Electrons in the Solar Wind

, ASTROPHYSICAL JOURNAL LETTERS, Vol: 871, ISSN: 2041-8205

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Citations: 57

Journal article

Nakamura R, Genestreti KJ, Nakamura T, Baumjohann W, Varsani A, Nagai T, Bessho N, Burch JL, Denton RE, Eastwood JP, Ergun RE, Gershman DJ, Giles BL, Hasegawa H, Hesse M, Lindqvist P-A, Russell CT, Stawarz JE, Strangeway RJ, Torbert RBet al., 2019,

Structure of the current sheet in the 11 July 2017 Electron Diffusion Region Event

, Journal of Geophysical Research: Space Physics, Vol: 124, Pages: 1173-1186, ISSN: 2169-9380

The structure of the current sheet along the Magnetospheric Multiscale (MMS) orbit is examined during the 11 July 2017 Electron Diffusion Region (EDR) event. The location of MMS relative to the X‐line is deduced and used to obtain the spatial changes in the electron parameters. The electron velocity gradient values are used to estimate the reconnection electric field sustained by nongyrotropic pressure. It is shown that the observations are consistent with theoretical expectations for an inner EDR in 2‐D reconnection. That is, the magnetic field gradient scale, where the electric field due to electron nongyrotropic pressure dominates, is comparable to the gyroscale of the thermal electrons at the edge of the inner EDR. Our approximation of the MMS observations using a steady state, quasi‐2‐D, tailward retreating X‐line was valid only for about 1.4 s. This suggests that the inner EDR is localized; that is, electron outflow jet braking takes place within an ion inertia scale from the X‐line. The existence of multiple events or current sheet processes outside the EDR may play an important role in the geometry of reconnection in the near‐Earth magnetotail.

Journal article

Turner DL, Kilpua EKJ, Hietala H, Claudepierre SG, O'Brien TP, Fenneill JF, Blake JB, Jaynes AN, Kanekal S, Baker DN, Spence HE, Ripoll J-F, Reeves GDet al., 2019,

The Response of Earth's Electron Radiation Belts to Geomagnetic Storms: Statistics From the Van Allen Probes Era Including Effects From Different Storm Drivers

, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 124, Pages: 1013-1034, ISSN: 2169-9380

Journal article

Angelopoulos V, Cruce P, Drozdov A, Grimes EW, Hatzigeorgiu N, King DA, Larson D, Lewis JW, McTiernan JM, Roberts DA, Russell CL, Hori T, Kasahara Y, Kumamoto A, Matsuoka A, Miyashita Y, Miyoshi Y, Shinohara I, Teramoto M, Faden JB, Halford AJ, McCarthy M, Millan RM, Sample JG, Smith DM, Woodger LA, Masson A, Narock AA, Asamura K, Chang TF, Chiang C-Y, Kazama Y, Keika K, Matsuda S, Segawa T, Seki K, Shoji M, Tam SWY, Umemura N, Wang B-J, Wang S-Y, Redmon R, Rodriguez JV, Singer HJ, Vandegriff J, Abe S, Nose M, Shinbori A, Tanaka Y-M, UeNo S, Andersson L, Dunn P, Fowler C, Halekas JS, Hara T, Harada Y, Lee CO, Lillis R, Mitchell DL, Argall MR, Bromund K, Burch JL, Cohen IJ, Galloy M, Giles B, Jaynes AN, Le Contel O, Oka M, Phan TD, Walsh BM, Westlake J, Wilder FD, Bale SD, Livi R, Pulupa M, Whittlesey P, DeWolfe A, Harter B, Lucas E, Auster U, Bonnell JW, Cully CM, Donovan E, Ergun RE, Frey HU, Jackel B, Keiling A, Korth H, McFadden JP, Nishimura Y, Plaschke F, Robert P, Turner DL, Weygand JM, Candey RM, Johnson RC, Kovalick T, Liu MH, McGuire RE, Breneman A, Kersten K, Schroeder Pet al., 2019,

The Space Physics Environment Data Analysis System (SPEDAS)

, SPACE SCIENCE REVIEWS, Vol: 215, ISSN: 0038-6308

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Citations: 290

Journal article

Janvier M, Winslow RM, Good S, Bonhomme E, Demoulin P, Dasso S, Moestl C, Lugaz N, Amerstorfer T, Soubrie E, Boakes PDet al., 2019,

Generic Magnetic Field Intensity Profiles of Interplanetary Coronal Mass Ejections at Mercury, Venus, and Earth From Superposed Epoch Analyses

, JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 124, Pages: 812-836, ISSN: 2169-9380

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Citations: 58

Journal article

Eastwood J, Hapgood MA, Biffis E, Benedetti D, Bisi MM, Green L, Bentley RD, Burnett Cet al., 2019,

Quantifying the economic value of space weather forecasting for power grids: An exploratory study

, Space Weather, Vol: 16, Pages: 2052-2067, ISSN: 1539-4956

An accurate understanding of space weather socioeconomic impact is fundamental to the development of appropriate operational services, forecasting capabilities, and mitigation strategies. One way to approach this problem is by developing physics‐based models and frameworks that can lead to a bottom‐up estimate of risk and likely impact. Here we describe the development of a new framework to assess the economic impact of space weather on power distribution networks and the supply of electricity. In particular, we focus on the phenomenon of the geomagnetic substorm, which is relatively localized in time and space, and occurs multiple times with varying severity during a geomagnetic storm. The framework uses the AE index to characterize substorm severity, and the impact of the substorm is modulated by the resilience of the power grid and the nature of available forecast. Possible scenarios for substorm sequences during a 1‐in‐10‐, a 1‐in‐30‐, and a 1‐in‐100‐year geomagnetic storm events are generated based on the 2003, 1989, and 1859 geomagnetic storms. Economic impact, including international spill over, can then be calculated using standard techniques, based on the duration and the geographical footprint of the power outage. Illustrative calculations are made for the European sector, for a variety of forecast and resilience scenarios. However, currently available data are highly regionally inhomogeneous, frustrating attempts to define an overall global economic impact at the present time.

Journal article

Stansby D, Horbury T, Matteini L, 2019,

Diagnosing solar wind origins using in situ measurements in the inner heliosphere

, Monthly Notices of the Royal Astronomical Society, Vol: 482, Pages: 1706-1714, ISSN: 0035-8711

Robustly identifying the solar sources of individual packets of solar wind measured in interplanetary space remains an open problem. We set out to see if this problem is easier to tackle using solar wind measurements closer to the Sun than 1 au, where the mixing and dynamical interaction of different solar wind streams is reduced. Using measurements from the Helios mission, we examined how the proton core temperature anisotropy and cross-helicity varied with distance. At 0.3 au there are two clearly separated anisotropic and isotropic populations of solar wind that are not distinguishable at 1 au. The anisotropic population is always Alfvénic and spans a wide range of speeds. In contrast the isotropic population has slow speeds, and contains a mix of Alfvénic wind with constant mass fluxes and non-Alfvénic wind with large and highly varying mass fluxes. We split the in situ measurements into three categories according these observations, and suggest that these categories correspond to wind that originated in the core of coronal holes, in or near active regions or the edges of coronal holes, and as small transients form streamers or pseudo-streamers. Although our method by itself is simplistic, it provides a new tool that can be used in combination with other methods for identifying the sources of solar wind measured by Parker Solar Probe and Solar Orbiter.

Conference paper

Nowack P, Ong QYE, Braesicke P, Haigh J, Abraham NL, Pyle J, Voulgarakis Aet al., 2019,

Machine learning parameterizations for ozone in climate sensitivity simulations

, Kurzfassungen der Meteorologentagung DACH

Journal article

Malik A, Nowack PJ, Haigh JD, Cao L, Atique L, Plancherel Yet al., 2019,

Supplementary material to &quot;Tropical Pacific Climate Variability under Solar Geoengineering: Impacts on ENSO Extremes&quot;

Journal article

Malik A, Nowack PJ, Haigh JD, Cao L, Atique L, Plancherel Yet al., 2019,

Tropical Pacific Climate Variability under Solar Geoengineering: Impacts on ENSO Extremes

<jats:p>Abstract. Many modelling studies suggest that the El Niño Southern Oscillation (ENSO), in interaction with the tropical Pacific background climate, will change under rising atmospheric greenhouse gas concentrations. Solar geoengineering (reducing the solar flux from outer space) has been proposed as a means to counteract anthropogenic greenhouse-induced changes in climate. Effectiveness of solar geoengineering is uncertain. Robust results are particularly difficult to obtain for ENSO because existing geoengineering simulations are too short (typically ~ 50 years) to detect statistically significant changes in the highly variable tropical Pacific background climate. We here present results from a 1000-year sunshade geoengineering simulation, G1, carried out with the coupled atmosphere-ocean general circulation model HadCM3L. In agreement with previous studies, reducing the shortwave solar flux more than compensates the warming in the tropical Pacific that develops in the 4×CO2 scenario: we observe an overcooling of 0.3 °C (5 %) and 0.23-mm day−1 (5 %) reduction in mean rainfall relative to preindustrial conditions in the G1 simulation. This is due to the different latitudinal distributions of the shortwave (solar) and longwave (CO2) forcings.The location of the Intertropical Convergence Zone (ITCZ) located north of equator in the tropical Pacific, which moved 7.5° southwards under 4×CO2, is also restored to its preindustrial location. However, other aspects of the tropical Pacific mean climate are not reset as effectively. Relative to preindustrial conditions, in G1 the zonal wind stress, zonal sea surface temperature (SST) gradient, and meridional SST gradient are reduced by 10 %, 11 %, and 9 %, respectively, and the Pacific Walker Circulation (PWC) is consistently weakened. The overall amplitude of ENSO strengthens by 5–8 %, but there is a 65 % reduct

Journal article

Papini E, Franci L, Landi S, Verdini A, Matteini L, Hellinger Pet al., 2019,

Can Hall Magnetohydrodynamics Explain Plasma Turbulence at Sub-ion Scales?

, ASTROPHYSICAL JOURNAL, Vol: 870, ISSN: 0004-637X

Journal article

Diaz-Aguado MF, Bonnell JW, Bale SD, Rezvani SJ, Koshmak K, Giglia A, Nannarone S, Gruntman Met al., 2019,

Experimental Investigation of Total Photoemission Yield from New Satellite Surface Materials

, JOURNAL OF SPACECRAFT AND ROCKETS, Vol: 56, Pages: 248-258, ISSN: 0022-4650

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Citations: 7

Journal article

Papini E, Franci L, Landi S, Hellinger P, Verdini A, Matteini Let al., 2019,

Statistics of magnetic reconnection and turbulence in Hall-MHD and hybrid-PIC simulations

, NUOVO CIMENTO C-COLLOQUIA AND COMMUNICATIONS IN PHYSICS, Vol: 42, ISSN: 2037-4909

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Journal article

Landi S, Franci L, Papini E, Matteini L, Verdini A, Hellinger Pet al., 2019,

Spectral anisotropies in high resolution three-dimensional simulations

, NUOVO CIMENTO C-COLLOQUIA AND COMMUNICATIONS IN PHYSICS, Vol: 42, ISSN: 2037-4909

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Journal article

Verdini A, Grappin R, Montagud-Camps V, Landi S, Franci L, Papini Eet al., 2019,

Numerical simulations of high cross-helicity turbulence from 0.2 to 1 AU

, NUOVO CIMENTO C-COLLOQUIA AND COMMUNICATIONS IN PHYSICS, Vol: 42, ISSN: 2037-4909

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Journal article

Tong Y, Vasko IY, Pulupa M, Mozer FS, Bale SD, Artemyev AV, Krasnoselskikh Vet al., 2019,

Whistler Wave Generation by Halo Electrons in the Solar Wind

, ASTROPHYSICAL JOURNAL LETTERS, Vol: 870, ISSN: 2041-8205

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Citations: 50

Journal article

Thompson DWJ, Ceppi P, Li Y, 2019,

A robust constraint on the temperature and height of the extratropical tropopause

, Journal of Climate, Vol: 32, Pages: 273-287, ISSN: 0894-8755

In a recent study, the authors hypothesize that the Clausius–Clapeyron relation provides a strong constraint on the temperature of the extratropical tropopause and hence the depth of mixing by extratropical eddies. The hypothesis is a generalization of the fixed-anvil temperature hypothesis to the global atmospheric circulation. It posits that the depth of robust mixing by extratropical eddies is limited by radiative cooling by water vapor—and hence saturation vapor pressures—in areas of sinking motion. The hypothesis implies that 1) radiative cooling by water vapor constrains the vertical structure and amplitude of extratropical dynamics and 2) the extratropical tropopause should remain at roughly the same temperature and lift under global warming. Here the authors test the hypothesis in numerical simulations run on an aquaplanet general circulation model (GCM) and a coupled atmosphere–ocean GCM (AOGCM). The extratropical cloud-top height, wave driving, and lapse-rate tropopause all shift upward but remain at roughly the same temperature when the aquaplanet GCM is forced by uniform surface warming of +4 K and when the AOGCM is forced by RCP8.5 scenario emissions. “Locking” simulations run on the aquaplanet GCM further reveal that 1) holding the water vapor concentrations input into the radiation code fixed while increasing surface temperatures strongly constrains the rise in the extratropical tropopause, whereas 2) increasing the water vapor concentrations input into the radiation code while holding surface temperatures fixed leads to robust rises in the extratropical tropopause. Together, the results suggest that roughly invariant extratropical tropopause temperatures constitutes an additional “robust response” of the climate system to global warming.

Conference paper

Pudney M, King S, Horbury T, Maksimovic M, Owen CJ, Laget Pet al., 2019,

SOLAR ORBITER STRATEGIES FOR EMC CONTROL AND VERIFICATION

, ESA Workshop on Aerospace EMC (Aerospace EMC), Publisher: IEEE

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Citations: 7

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Machine learning parameterizations for ozone in climate sensitivity simulations

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