The Investigation of Convective Updrafts (INCUS) mission includes three small satellites flying in the same orbit plane with 30-120 seconds separation to study why convective storms, heavy precipitation, and clouds occur exactly when and where they form. Each satellite has a precipitation radar and one of the satellites includes a passive microwave radiometer. The Dynamic Microwave Radiometer (DMR) provides retrievals of cloud ice water path and water vapor profiles in the surrounding environment. DMR is a five-frequency millimeter-wave radiometer operating in the 87–181 GHz range. It will be deployed as part of the second spacecraft in the INCUS mission, scheduled for launch no earlier than October 2026. The DMR employs direct-detection architecture, achieving a compact design with a mass of 9.4 kg and power consumption of 10.3 W, by eliminating the need for a local oscillator and mixer. This architecture reduces system complexity while maintaining high performance. The instrument features a continuously rotating scanning reflector, enabling cross-track measurements that include views of a blackbody calibration target, the Earth over a range of incidence angles, and the cosmic microwave background radiation at 2.73 K. This configuration provides end-to-end calibration of the millimeter-wave receivers during each scan cycle. The radiometer leverages 35-nm Indium Phosphide (InP) high-electron-mobility transistor (HEMT) low-noise amplifiers (LNA) to ensure high sensitivity and precision. This paper provides an overview of the DMR's receiver design and pre-launch characterization.

Abstract We report on new observations of Io upwelling thermal emission over the range of 0.6–22 GHz acquired with the Juno Microwave Radiometer in December 2023 and February 2024. The microwave emission spectrum from the surface of Io is retrieved from the calibrated brightness temperatures by characterizing and removing reflections from the sky. The surface appears to exhibit specular reflection in the microwave, suggesting a relatively smooth surface on 100 km spatial scales (apart from visible topography), like Earth's land and ocean surfaces. The real part of the dielectric constant is found to be in the range of 2–4; constrained by overlapping observations on the surface from two viewing geometries. This relatively low value is consistent with a density of 0.7–1.1 g/cm 3 of the surface layer (<10 cm depth). A large spectral slope is observed at all latitudes in the lowest frequency channels suggesting significant endogenic near‐surface heating. Two simple models are applied to explain the MWR spectra. A model with a conducive near‐surface layer implies heat flows ranging from 1 to 3 W/m 2 . Alternately, relatively fresh lava flows (<5 years) or heat vents covered by a cooling crust on the order of 10 m over about 10% of the surface area can also explain the spectral gradient.

The Planetary Boundary Layer (PBL) is the lower portion of the troposphere that is directly influenced by the Earth’s surface where the most of the energy exchange with respect to solar heating and evaporation that drive the atmosphere and the ocean happen. The current generation microwave instruments fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of the interest for PBL sensing. Therefore, it is a critical need to capture a significant portion of the microwave spectrum to sense the PBL.

The ultra-wideband RF photonics spectro-radiometer instrument is under development for the Planetary Boundary Layer (PBL) sensing. The PBL is the lower portion of the troposphere that is directly influenced by the Earth's surface. Most of the energy exchange with respect to solar heating and evaporation that drive the atmosphere and the ocean occur within PBL. Passive microwave instruments can be a critical component to a PBL observing system but the current generation microwave instruments fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of the interest for PBL sensing. It is adequate for providing thermodynamic information in both cloudy and clear air, cloud and precipitation properties and surface flux information including temperature and wind speed but not optimized for near surface sensing.

The NASA Juno mission performed two close fly-bys of Jupiter’s moon Io on December 30, 2023 and February 3, 2024. Juno carries a 6-channel microwave radiometer (MWR) operating between 0.6-22 GHz. The first fly-by observed Io’s north pole and the 2nd pass mapped latitudes within +/- 45o on the Jovian facing hemisphere. The broad frequency range of the MWR probes successively deeper into the Io sub-surface with the 0.6GHz channel probing the deepest. The penetration depth into the sub-surface of the highest frequency channels is on the order of centimeters and the lowest frequency on the order of several 10s of meters. We find the surface of Io generally exhibits specular scattering properties over the 0.6-22 GHz frequency range. We use overlapping observations from the two fly-bys that observe the same areas at different incidence angles and polarizations to solve for the surface dielectric properties. We find the surface dielectric (real part) to be between 2-3, which is consistent with a low-density material. We use the MWR derived real part of the dielectric constant (reflection) with Earth analogs for the imaginary part (loss) to derive the sub-surface temperature profile by inverting the radiative transfer equation. We find the near-surface temperatures decrease with increasing latitude and are coldest at the north pole, consistent with prior infrared observations of the surface skin temperature. We find a strong sub-surface thermal gradient, on the order of 20-40K, over all regions observed by MWR. The sub-surface thermal anomaly is not spatially uniform. We fit several possible models to explain this gradient. One possible explanation are spatially distributed near-surface heat vents topped by a cooled crust, which fit the MWR spectra if they occupy 5-10% of the surface area. We will give an overview of the MWR observations and inferences about the sub-surface thermal and compositional properties.

Most of the energy exchange in the atmosphere occurs in the atmospheric boundary layer (ABL) with respect to solar heating and evaporation. Remote sensing in the ABL from space is challenging because of its proximity to the surface and potential sharp gradients in air properties. Passive microwave instruments can be a critical component to a ABL observing system since they provide thermodynamic information in both cloudy and clear air, including cloud and precipitation properties, and surface flux information such as temperature and wind speed. However, conventional passive microwave systems fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of interest for ABL sensing.The near surface thermodynamic structure information is encoded on the microwave spectrum between and on the shoulders of the water vapor absorption and oxygen lines near 183 GHz and 118 GHz respectively. The ultra-wideband photonic spectro-radiometer instrument is funded by NASA ESTO under ACT-20 program to combine low-noise wideband InP RF technology with a novel photonic integrated circuit (PIC) design for obtaining large bandwidth (>50 GHz) with enhanced channel resolution (

Introducing cover crops and diversifying annual crop rotations can provide additional carbon (C) input to soils and are practices that have been promoted as climate change mitigation measures. However, year-round field studies are needed to evaluate the net effect on carbon dioxide (CO2) uptake, including consideration of carbon removal from the field during harvest depending on the crop grown to diversify the rotation. In addition, evaluation of net greenhouse gas (GHG) emissions requires accounting for changes in soil nitrous oxide (N2O) and CO2 emissions from production of farm inputs and field operations in the altered crop rotation. In this study, our objectives were to evaluate the annual dynamics of CO2 exchange and to estimate net GHG emissions for a diverse (DIV) corn-soybean-winter wheat crop rotation that included cover crops and a conventional (CONV) corn-soybean-soybean crop rotation. The year-round net ecosystem exchange (NEE) of CO2 on two side-by-side 8-ha fields (one under DIV and one under CONV management) was measured using the eddy covariance method over three years (2018-2021) in Ontario, Canada. Results showed that DIV rotation significantly increased cumulative NEE, gross primary production (GPP), and ecosystem respiration (Re) -578, -3750 and 3170 g C m(-2), respectively, compared to the CONV (-501, -3361, 2859 g C m(-2)) over three years. Overall, the DIV rotation resulted in a 15 % increase in NEE compared to CONV. Accounting for the grain C removed during harvest, on an annual basis, DIV and CONV corn and soybean fields were C sources. However, net ecosystem carbon budget (NECB) was a sink (-44 g C m(-2)) for DIV winter wheat + cover crops if only grain was removed and reversed to a C source (197 g C m(-2)) with straw + grain removal. The summed NECB across the three study years revealed that both fields were C sources (NECB > 0). Similarly, the DIV rotation was a net GHG source compared to CONV for straw + grain removal but had similar net GHG emission to CONV when only wheat grain was removed. From the present study, DIV did not reduce the net GHG emissions in the short term (3 years) as expected, but long-term measurements are needed to confirm this trend. Further multi-year eddy covariance and soil carbon stock measurements should be done to design effective diversified crop rotations.

Existing studies have shown contradictory findings with respect to whether biosolids applications on agricultural lands lead to intensification of soil greenhouse gas (GHG) emissions. Here, we describe the results of deployment of the micrometeorological flux gradient method to quantify post-biosolid soil emissions of nitrous oxide (N2O) and methane (CH4) on a farm with drainage water management (DWM) on the Eastern Shore of Maryland. The fluxes following biosolid additions to cornfields in 2020 were compared with fluxes from the same farm in 2018, when no fertilizer was applied to soybeans, and in 2019, when urea ammonium nitrate (UAN) was applied to corn. Extractable soil nitrate was highest following biosolids application, contributing to the highest N2O emissions in the growing season of 2020 compared to 2018 (no fertilizer) and 2019 (UAN). Other contributing factors include the low C:N ratio of the biosolids and the above average precipitation in 2020. In contrast, different fertilization regimes did not generate distinct differences for CH4 fluxes, which were very low in all three years. No statistically significant treatment effect of DWM was found for either N2O or CH4 during the peak emission period after biosolids application, which aligns with the result of our earlier research. Annualized estimated N2O emission factors (EFs) for biosolids addition were 5-6 % in the DWM and 3-4 % in the non-DWM fields, although this includes uncertainties associated with gap filling. These biosolids EFs are 2-3 times the N2O EF for synthetic fertilizer application at this same farm in 2019 (1-2.5 %) and 2-4 times the IPCC Tier 1 EF (1.6 %) for synthetic fertilizer, demonstrating the intensification effect of biosolids addition on soil N2O emissions for the cropland studied here.

We present six nearly full-sky maps made from data taken by radiometers on the Juno satellite during its 5 yr flight to Jupiter. The maps represent integrated emission over ∼4% passbands spaced approximately in octaves between 600 MHz and 21.9 GHz. Long-timescale offset drifts are removed in all bands, and, for the two lowest-frequency bands, gain drifts are also removed from the maps via a self-calibration algorithm similar to the NPIPE pipeline used by the Planck Collaboration. We show that, after this solution is applied, statistical noise in the maps is consistent with thermal radiometer noise and expected levels of correlated noise on the gain and noise drift solutions. We verify our map solutions with several consistency tests and end-to-end simulations. We also estimate the level of systematic pixelization noise and polarization leakage via simulations.

The NASA Juno mission performed two close fly-bys of Jupiter’s moon Io on December 30, 2023 and February 3, 2024. Juno carries a 6-channel microwave radiometer (MWR) operating between 0.6-22 GHz. The first fly-by observed Io’s north pole and the 2nd pass mapped latitudes within +/- 45o on the Jovian facing hemisphere. The broad frequency range of the MWR probes successively deeper into the Io sub-surface with the 0.6GHz channel probing the deepest. The sub-surface temperature, dielectric and surface roughness properties are encoded in the spectra obtained by the MWR. Here we report on the first spatially resolved observations of Io at frequencies below 22 GHz. We find the brightness temperatures decrease with increasing latitude and are coldest at the north pole, consistent with prior infrared observations of the surface skin temperature. We observe a strong spectral gradient in the lowest frequency channels (increasing with depth) reflecting the sub-surface temperature profile from which we can infer endogenic heat flow. We will give an overview of the MWR observations and initial inferences about the sub-surface thermal and compositional properties.

The Atmospheric Boundary Layer (ABL) is the portion of the troposphere that is directly influenced by the Earth’s surface and responds to combined action of mechanical and thermal forcing. Most of the energy exchange with respect to solar heating and evaporation that drive the atmosphere and the ocean occur within the ABL, yet it is one of the most poorly observed and modeled regions of the atmosphere. Conventional passive microwave systems fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of interest for ABL sensing. The so called “window regions” of the microwave spectrum between and on the shoulders of the strong oxygen and water vapor absorption lines carry the information on the near surface thermodynamic structure in the boundary layer. Sampling these regions requires new spectrometers capable of resolving >50 GHz spectral regions at modest spectral resolution (~1GHz). The ultra-wideband photonic spectro-radiometer instrument is funded by NASA ESTO under ACT-20 program to combine low-noise wideband RF technology with a novel photonic integrated circuit (PIC) design for obtaining large bandwidth (>50 GHz) with enhanced channel resolution (

Retrieving atmospheric water vapor and temperature profiles over land using microwave radiometry is challenging due to uncertainties in estimating surface emissions. To address this, we developed an approach that couples the atmospheric retrieval algorithm with the surface emission estimation in an iterative loop. Using sounding channels from Ka- to G-band on the Advanced Technology Microwave Sounder (ATMS), we retrieved temperature and humidity profiles across the Antarctic region throughout the year 2016. The atmospheric profiles are updated in each iteration and used in the following step to refine the surface emissivity. This process continues until the atmospheric solution converges. The main innovation is the integration of surface and atmospheric retrievals, which improves overall accuracy. We validated our results against in situ radiosonde data. The algorithm accurately retrieved temperature profiles, along with surface emissivity across 23-165 GHz, and successfully detected ice sheet meltings. While it captured water vapor variability, accurate absolute humidity values still require an independent surface emissivity retrieval using additional observations.

Nitrous oxide (N2O) emissions from agricultural soils occur as pulses presenting a challenge for assessing mitigation practices. Since the timing and magnitude of pulses is dependent on soil and climatic conditions, side-by-side comparisons are needed. The flux gradient (FG) and eddy covariance (EC) methods both capture spatially and temporally variable N2O emissions, but FG requirements are more flexible for operation using low power and/or in a multi-plot configuration with one gas analyzer. Instrumentation for N2O flux measurement requires strong pumps (> 500 W), limiting deployment. Here we developed new instrumentation using the FG method with minimal power (∼30 W). Field measurements were conducted in 2017 and 2018 in an agricultural field in Ontario, Canada to test the equipment's measurement quality, power consumption, and ease-of-use. A low-power FG system (FGLP) was co-located with an N2O EC flux tower (N2O-EC) and an existing multi-plot FG system (FGMP) was operated ∼50 m away. The FGLP fluxes correlated well with N2O-EC (r2 = 0.97, slope = 1.05), and ran uninterrupted with minimal maintenance using only 30 W. The non-co-located FGMP still showed relatively good correlation with N2O-EC (r2 = 0.65) through the growing season although there was a mismatch in measurement footprints, and N2O fluxes are well-known to occur in hot spots. Better agreement was observed for FGMP measured CO2 fluxes and the EC system (slope = 0.97, r2 = 0.93), giving additional confidence in the FGMP. The FG systems captured important N2O pulses during rainy, foggy and dewy periods when N2O-EC data was discarded. Results confirmed the functionality of the new FGLP system and verified FG measurements against EC N2O fluxes. The low power option provides possibilities to expand measurement to locations with power restrictions using a multi-plot configuration for side-by-side comparisons essential for evaluating effects of agricultural practices on N2O emissions.

Abstract. Retrieving atmospheric water vapor and temperature profiles presents considerable challenges over land surfaces using microwave radiometry due to uncertainties associated with estimating background surface emissions. In response, we have devised an approach that integrates the atmospheric retrieval algorithm with the background emission algorithm, establishing an iterative loop to refine the accuracy of atmospheric profiles. Leveraging optimal estimation techniques with sounding channels spanning from Ka- to G-band obtained from ATMS, we successfully retrieved atmospheric temperature and humidity profiles across space and time. These retrieved atmospheric profiles undergo continual updates throughout each iteration, exerting influence on subsequent surface retrievals. This iterative process persists until convergence is achieved in the atmospheric retrieval. The algorithm's novelty lies in its fusion of surface retrieval with atmospheric retrieval, thereby enhancing overall accuracy. We validated the retrievals against radiosonde data. Our iterative algorithm proved to be efficient and accurate in retrieving temperature profiles with surface emissivity and in detecting melting events. Though our algorithm was able to capture the water vapor variations, the results showed that to obtain accurate absolute values of the water content an independently retrieved surface emissivity is required.

The Planetary Boundary Layer (PBL) is the portion of the troposphere that is directly influenced by the Earth's surface and responds to combined action of mechanical and thermal forcing. Most of the energy exchange with respect to solar heating and evaporation that drive the atmosphere and the ocean occur within the PBL, yet it is one of the most poorly observed and modeled regions of the atmosphere. Passive microwave instruments will be a critical component to a PBL observing system. Microwave passive instruments provide thermodynamic information in both cloudy and clear air, cloud and precipitation properties and surface flux information including temperature and wind speed. However, conventional passive microwave systems fall well short of being optimized for near surface sensing due to limited number of spectral channels and coarse spectral resolution covering only a small portion of the spectrum of interest for PBL sensing.

Croplands that experience seasonal soil freezing and thawing have been shown to be significant sources of N2O emissions. Yet, there is a paucity of year-round N2O emission data for one of the most significant crop production regions that seasonally freeze, the Prairies. Here, we present micrometeorological N2O fluxes measured over 4 years in Saskatchewan, Canada, to evaluate the magnitude of freeze-thaw N2O emissions and investigate its driving factors. Significant thaw related emissions occurred in 2 of the 4 years and were associated with relatively higher fall nitrate levels and a more gradual soil thawing period. Overall, fall soil nitrate levels were a strong explanatory variable for the differences in non-growing season (NGS) N2O emission (r(2) = 0.485). Measured cumulative N2O emissions for the NGS were 123-938 g N ha(-1) and were much smaller than those obtained at other cold climate sites but amounted to 52% of annual totals on average. The November to April period contributed 30% of the annual total emissions in years without major thaw events, but 70% in years with significant thaws. NGS N2O emissions were not explained by cumulative freezing degree days unlike most other cold climate sites. We propose that NGS N2O emissions are more strongly influenced by thaw dynamics during freezing-thawing conditions in dry regions, whereas freezing intensity is the dominant factor for wetter regions. Our results indicate that even for a semi-arid region freeze-thaw is an important source of N2O emissions and must be considered for more accurate reporting and development of mitigation strategies.

Agriculture significantly contributes to global soil nitrous oxide (N2O) emissions. Crop rotation diversification and cover cropping are feasible agronomic strategies to reduce nitrogen losses to the environment. However, input of cover crop residues could potentially increase soil N2O emissions. Dual nitrification and urease inhibitors (NUI) administered after cover crop termination at the time of nitrogen fertiliser addition could reduce emissions, but this has not been widely evaluated in field studies. A 4-year crop rotation study was conducted to determine the effect of crop diversification and use of NUI on N2O emissions, crop yield and N2O intensity. Nitrous oxide flux was measured year-round using a micrometeorological method deployed on four 4-ha fields. Two fields were managed with a conventional crop rotation (CONV) (corn - soybean - soybean) and two fields were managed with a diverse crop rotation (DIV) (corn - soybean - winter-wheat plus cover crops either as 2species mixture under seeded to corn or 4-species mixture after winter-wheat harvest). The effect of a NUI [N(-nButyl) thiophosphoric triamide and Pronitridine] was tested in corn in the fourth year. The DIV rotation resulted in 43 % lower annual N2O emissions when winter wheat was grown instead of soybean and 18-26 % increase in annual N2O emissions for corn. The DIV rotation increased N2O intensity by 15 % in Year 1 and 36 % in Year 4 compared to corn in the CONV rotation. The use of NUI in DIV rotation resulted in 15 % lower total N2O emissions over 3 years of the rotation cycle. The application of NUI resulted in a 19 % reduction in N2O intensity within the DIV rotation, with no observable effect on corn yield. Further research should focus on optimising the N application rates according to NUI use, considering available nitrogen from crop residues and cover crops when integrated into the crop rotation.

IntroductionThis is a preliminary report on measurements by Juno’s Microwave Radiometer (MWR) of cyclonic vortices in Jupiter’s north polar region. Juno discovered cyclones close to both rotational poles, surrounded by constellations of circumpolar cyclones (CPCs) ~7° from the poles with diameters of ~4000-6000 km (Orton et al. 2017, Adriani et al. 2018). The CPCs move very slowly in longitudes fixed to the interior (System-III) and are stable in their general morphology (‘filled’ vs ‘chaotic’ or ‘spiral’) in the visible or at 5 µm (Tabataba-Vakili et al. 2020, Adriani et al. 2020, Mura et al. 2022). Mura et al. (2021, 2022) noted that the longevity and stability of the CPCs raises questions about their depth. Models range from shallow-water (Li et al. 2020) to deep convection (e.g. Yadav et al. 2020, Garcia et al. 2020, Cai et al. 2021). Credible 3D models require knowledge of their properties at depth.MWR ObservationsMWR observations, 1.38 - 50 cm in wavelength (Janssen et al. 2017), sense Jupiter at pressures of 0.7 to over 100 bars (Figure 1). Only recently could the MWR resolve the northern CPCs and North Polar Cyclone (NPC), enabled by successive close approaches (“perijoves” or PJs) migrating northward, shortening the distance between the spacecraft and the north polar region. The CPCs are all recognizable in Ch. 6, as relatively bright, with CPCs 2, 6 and 8 much dimmer than the others (Fig. 2). Unlike the CPCs, the NPC has one of the coldest antenna temperatures in the region. Figure 3 shows that CPCs 1, 3, 4, 5 and 7 are detectable in Ch. 4-6. CPCs 2, 6 and 8 are undetectable in Ch. 3-5. CPCs 3, 5, and 7 are detectable in Ch. 3. A feature associated with CPC 1 could be present but is indistinguishable from a broad, warm background region. The North Polar Cyclone has a relatively colder antenna temperature in all channels.DiscussionThe MWR maps are remarkable. The chaotic or spiral CPCs (2, 6 and 8) are faint, smaller and closer to the rotational pole than the filled CPCs 1, 3, 5 and 7. The strength of all the cyclones (positive for the CPCs and negative for the NPC) diminish with depth. The virtual disappearance of chaotic/spiral CPCs 2, 6 and 8 in channels sensitive to pressures of 1.5 – 3 bars implies that they are probably shallower than the prominent, filled CPCs. The appearance of CPCs in Ch. 3 means they have roots down to at least 9 bars of pressure. MWR observations of a cyclonic vortex at 38°N (Bolton et al. 2021) showed a similar behavior, but its brightness temperature ‘signature’ changed from positive to negative in Ch. 3, implying an inversion around 3-6 bars. An inversion is not evident here for either chaotic/spiral CPCs or the filled CPCs, except possibly for CPC4. Bolton et al. (2021) noted that if the warm brightness temperature is the result of a lower NH3 abundance, a dynamical mechanism is needed to transport ammonia downward from the upper atmospheric layers. A similar mechanism may be responsible for the northern CPCs, with the diversity of their strengths and depth dependences governed by a range of cyclonic vorticities. The cold NPC remains the most puzzling, as it is more similar to anticyclones, e.g. the Great Red Spot and an anticyclone at 19°N (Bolton et al. 2021), requiring higher NH3 abundances or colder temperatures. Separating physical temperatures and NH3 opacity is possible using observations resolving the cyclones over a range of emission angles, an approach successfully used for Jupiter’s equator (Li et al. 2024). We will take advantage of this using MWR measurements of this region at increasing spatial resolution between now and the expected mission end in late 2025.Some of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).Figure 1. Contribution functions of MWR channels. Measurements from Ch. 1 and 2, were not used in this study; their fields of view are twice as large as Ch. 3-6, and they did not resolve the CPCs sufficiently.Figure 2. The morphologies of the region northward of 78° planetocentric latitude from three Juno instruments. Longitudes are 0° at the bottom and increase clockwise. The MWR map shows composite antenna temperatures for Ch. 6 PJ52-PJ60. The MWR fields of view are about the same size as the CPCs shown at higher resolution by JunoCam and JIRAM. The JunoCam map combines PJ57 and PJ58, and the 5-µm JIRAM map is the last contiguous one of this region. The North Polar Cyclone (“NPC”) and numerical CPC labels are shown in the JunoCam panel. The locations of the CPCs are very similar in each of the maps, due to their very slow longitudinal motion in System III.Figure 3. MWR maps of antenna temperature from PJ60 observations in Ch. 3-6 with the same orientation as in Fig. 2, together with the pressure of the contribution function maximum of each channel (see Fig. 1). The fields of view of these channels are the same. Numerical identifications of the CPCs are shown. The keys give the respective range of antenna temperature values for each channel. ReferencesAdriani, A. et al. 2018. Nature 555, 216.Adriani, A. et al. 2020. J. Geophys. Res. Planets 125, e2019JE006098.Bolton et al. 2021. Science 374, 968.Cai, T. et al. 2021. Planet. Sci. J. 2, 81.Janssen, M. et al. 2017. Space Sci. Rev. 213, 139.Garcia, F. et al. 2020. Mon. Not. Roy. 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