Browse Articles
Supernova Rates and Burial of Organic Matter
-  5 January 2022
Key Points
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The fraction of organic carbon buried in marine sediments covaries with changes in supernova frequency over most of the Earth's history
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Supernovae influence Earth via a link between atmospheric ionization, clouds and climate. High cosmic ray flux leads to a cold climate
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Climatic induced ocean circulation regulates nutrients to the biosphere. A larger bioproductivity results in increased organic matter burial
Multiple Leaking Mode Dispersion Observations and Applications From Ambient Noise Cross‐Correlation in Oklahoma
-  28 December 2021
Key Points
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Multiple leaking mode dispersion curves are extracted from ambient noise cross-correlation functions
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Spatial stacking and time windows are used to enhance the leaking modes
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The joint inversion of leaking and normal modes can reliably generate the P-wave velocity (Vp) and Vp/Vs ratio structures
Air Quality Forecasts Improved by Combining Data Assimilation and Machine Learning With Satellite AOD
-  28 December 2021
Key Points
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Conventional aerosol data assimilation (DA) suffers from large uncertainties when using satellite aerosol optical depth (AOD) observations
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Machine learning was applied to estimate ground particulate matter (PM) concentrations from the satellite AOD for use in the conventional 3D-VAR DA system
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The modified DA experiment remarkably improves the PM10 and PM2.5 prediction performance compared to the conventional AOD DA experiment
3D Joint Inversion of Scanning Magnetic Microscopy Data
-  28 December 2021
Key Points
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Magnetic data and microscopic inspection indicate the main source of remanent magnetization is oxide exsolution lamellae in pyroxenes
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Simultaneous inversion of scanning magnetic microscopy data acquired above and below the sample indicate heterogeneous magnetization
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Magnetic inversion results are consistent with sample's bulk remanent magnetization measurements
Zonal Structure of Tropical Pacific Surface Salinity Anomalies Affects ENSO Intensity and Asymmetry
-  28 December 2021
Key Points
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El Niño-Southern Oscillation (ENSO) intensity is sensitive to the zonal location of sea surface salinity (SSS) anomalies and becomes strongest when they are located in the central Pacific
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Asymmetric zonal structure of SSS anomalies strengthens the asymmetry of sea surface temperature (SST) anomalies between El Niño and La Niña
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Vertical mixing and entrainment dominate SSS-related SST changes during ENSO cycle
Examining the Wind Shear Theory of Sporadic E With ICON/MIGHTI Winds and COSMIC‐2 Radio 2 Occultation Data
-  28 December 2021
Key Points
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Conjunction observations of sporadic E (Es) from COSMIC-2 and neutral wind profiles from Ionospheric Connection Explorer/Michelson Interferometer for Global High-Resolution Thermospheric Imaging are analyzed
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Es occurrence rate correlates with the negative vertical shear of eastward wind, providing observational evidence for the wind shear theory
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Es can be observed even when the vertical shear of the local eastward wind is positive
Post‐Perovskite Phase Transition in the Pyrolitic Lowermost Mantle: Implications for Ubiquitous Occurrence of Post‐Perovskite Above CMB
-  28 December 2021
Key Points
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We conducted synchrotron X-ray diffraction measurements of a pyrolitic mantle material up to 4480 K at 122–166 GPa in a laser-heated diamond anvil cell
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Phase transition between bridgmanite and post-perovskite occurs in pyrolite within the lowermost mantle pressure range even at >4000 K
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Ubiquitous occurrence of post-perovskite above the core-mantle boundary is consistent with recent high-quality seismological observations of D" reflections
The seesaw pattern of PM2.5 interannual anomalies between Beijing‐Tianjin‐Hebei and Yangtze River Delta across eastern China in winter
-  4 January 2022
Key Points
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A seesaw pattern of PM2.5 interannual anomalies between Beijing-Tianjin-Hebei (BTH) and Yangtze River Delta (YRD) was found
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The difference in regional transport driven by interannual variation in the East Asian winter monsoon (EAWM) was the dominant mechanism
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Higher PM2.5 anomalies in northern BTH during the COVID-19 lockdown were mainly caused by the nonactive EAWM
On The Estimation of Internal Climate Variability During the Preindustrial Past Millennium
-  4 January 2022
Key Points
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Climate model ensembles driven by estimated radiative forcing can be used to estimate both forced and internal climate variability
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Such exercises can yield biased results in the presence of uncertainty in both forcing and response as pertains to the past millennium
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Ensemble analysis shows a widely used procedure yields biased results for past millennium
Modeling the Occurrence of M∼5 Caldera Collapse‐Related Earthquakes in Kīlauea Volcano, Hawai‘i
-  28 December 2021
Key Points
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Kīlauea caldera collapse-related seismicity is a source of seismic hazard in Hawai‘i and should be included in a complete seismic hazard assessment
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Their occurrence is modeled by combining distributions for the number of caldera collapses and number of earthquakes per collapse
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The event occurrence model is non-Poisson, and this approach may be generalizable for other seismogenic processes
Slope break and avulsion locations scale consistently in global deltas
-  28 December 2021
Key Points
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Morphometric boundaries investigated in 105 modern deltas globally
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Slope break and avulsion lengths show the strongest scaling relationship, more significant than previous scaling relationships
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Processes contributing to this slope-break avulsion length scaling relationship are proposed along with conceptual model of the implications
Urbanization Aggravates Effects of Global Warming on Local Atmospheric Drying
-  28 December 2021
Key Points
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‘Urban Dry Islands’ (UDI) effects are detected across a large climatic gradient
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Urbanization exacerbates global warming and UHI effects on UDI through reducing evapotranspiration and water vapor availability
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The magnitude and frequency of UDI are more pronounced in humid regions than arid regions due to differences in vegetation and climate
A marginal stability paradigm for shear‐induced diapycnal turbulent mixing in the ocean
-  28 December 2021
Key Points
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Turbulence emerges in a marginally stable ocean interior by localized bursts in shear
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Data suggests shear instability is the prevalent facilitator of turbulence, even close to boundaries
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The marginally unstable turbulent patches seem to mix optimally during most of their life cycles
San Andreas fault stress change due to groundwater withdrawal in California’s Central Valley, 1860‐2010
-  28 December 2021
Key Points
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We estimate Central Valley groundwater unloading viscoelastic effects on present-day central San Andreas (CSAF) fault stressing
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Coulomb stress change for the CSAF during the 2006-2010 drought corresponds positively with seismicity and low frequency earthquakes
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Cumulative Coulomb stress change on the CSAF for 1860-2010 is on the order of ∼0.01-0.02 MPa depending on the lower crustal viscosity
A new parameterization of turbulent mixing enhanced over rough seafloor topography
-  28 December 2021
Key Points
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We parameterize the turbulent mixing enhanced over high-wavenumber bathymetry with a revised formulation of its vertical decay scale
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The vertical decay scale of bottom-enhanced mixing is given by the vertical mean free path of internal lee waves from the ocean bottom
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The upward extent of mixing is in proportion to the abyssal current velocity squared and the inverse abyssal buoyancy frequency squared
Role of Electrical Effects in Intensifying Rainfall Rates in the Tropics
-  28 December 2021
Key Points
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Cloud electric field substantially modifies the raindrop size distribution
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WRF model simulations show a significant underestimation of the observed rain intensity for strongly electrified rain events
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The simulated rain intensity improved significantly with the incorporation of electrically modified raindrop size distribution parameters
Saturn’s weather‐driven aurorae modulate oscillations in the magnetic field and radio emissions
-  28 December 2021
Key Points
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Keck-NIRSPEC observations of Saturn’s northern infrared auroral emission from 2017 are analysed
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First clear picture of how the ionosphere moves in relation to planetary period currents is provided
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Saturn’s measured variable rotation rate is driven by twin-vortex flows in the upper atmosphere
Impact of Coronavirus Outbreak on NO2 Pollution Assessed Using TROPOMI and OMI Observations
- Geophysical Research Letters
-  8 May 2020
The Response in Air Quality to the Reduction of Chinese Economic Activities During the COVID‐19 Outbreak
- Geophysical Research Letters
-  18 May 2020
Extending the Global Mass Change Data Record: GRACE Follow‐On Instrument and Science Data Performance
- Geophysical Research Letters
-  24 May 2020
Puzzling Haze Events in China During the Coronavirus (COVID‐19) Shutdown
- Geophysical Research Letters
-  9 June 2020
Disentangling the Impact of the COVID‐19 Lockdowns on Urban NO2 From Natural Variability
- Geophysical Research Letters
-  17 August 2020
Continuity of Ice Sheet Mass Loss in Greenland and Antarctica From the GRACE and GRACE Follow‐On Missions
- Geophysical Research Letters
-  18 March 2020
Robust Future Changes in Meteorological Drought in CMIP6 Projections Despite Uncertainty in Precipitation
- Geophysical Research Letters
-  10 May 2020
September 2019 Antarctic Sudden Stratospheric Warming: Quasi‐6‐Day Wave Burst and Ionospheric Effects
- Geophysical Research Letters
-  8 January 2020
COSMIC‐2 Radio Occultation Constellation: First Results
- Geophysical Research Letters
-  5 February 2020
3D Joint Inversion of Scanning Magnetic Microscopy Data
- Geophysical Research Letters
-  28 December 2021
Saturn’s weather‐driven aurorae modulate oscillations in the magnetic field and radio emissions
- Geophysical Research Letters
-  28 December 2021
Cloud‐to‐ground lightning and near‐surface fire weather control wildfire occurrence in Arctic tundra
- Geophysical Research Letters
-  28 December 2021
A Climatology of Narrow Cold‐Frontal Rainbands in Southern California
- Geophysical Research Letters
-  20 December 2021
Activation of Abundant Recoil Leaders and Their Promotion Effect on the Negative‐End Breakdown in an Intracloud Lightning Flash
- Geophysical Research Letters
-  28 December 2021
Singing Comet Waves in a Solar Wind Convective Electric Field Frame
- Geophysical Research Letters
-  9 April 2020