Results 71 to 80 of about 12,264 (254)

Spatial observation‐error correlations for AMSU‐A in all‐sky assimilation: An ECMWF and UK Met Office intercomparison

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Assimilation of AMSU‐A all‐sky observations can be increased up to fivefold if spatial observation‐error correlations are accounted for properly. New correlation estimates derived using data from ECMWF and the UK Met Office reveal that correlation length‐scales are between 75 and 150 km for AMSU‐A channels peaking in the troposphere. This is attributed
Rishabh Bhatt, Massimo Bonavita, Niels Bormann, Sarah L. Dance, Alison Fowler, Elías Hólm, Christopher J. Merchant, Jonathan Mittaz, Stuart Newman, Joanne Waller   +9 more
wiley   +1 more source

Global perspectives on nitrate aerosol dynamics: a comprehensive sensitivity analysis [PDF]

Atmospheric Chemistry and Physics
In recent years, nitrate aerosols have become a dominant component of atmospheric composition, surpassing sulfate in both concentration and climatic impact. However, accurately simulating nitrate remains a major challenge for global models due to complex
A. Milousis, S. M. C. Scholz, H. Fuchs, H. Fuchs, A. P. Tsimpidi, V. A. Karydis   +5 more
doaj   +1 more source

Impact of Weak‐Constraint Four‐Dimensional Variational data assimilation on the prediction of a sudden stratospheric warming event in 2024

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The Weak‐Constraint Four‐Dimensional Variational (WC‐4DVAR) system markedly improved the analysis and forecasting of the 2024 sudden stratospheric warming (SSW) event. It reduced biases and enhanced 7–9 day predictions of temperature across the SSW life cycle, with the most pronounced gains for winds also during the critical onset period.
Shaoying Li, Weimin Zhang, Shuo Ma, Bainian Liu, Yanlai Zhao, Xiaoqun Cao   +5 more
wiley   +1 more source

Kinetics of the reactions of OH with CO, NO, and NO₂ and of HO₂ with NO₂ in air at 1 atm pressure, room temperature, and tropospheric water vapour concentrations [PDF]

Atmospheric Chemistry and Physics
The termolecular reactions of hydroxyl radicals (OH) with carbon monoxide (CO), nitric oxide (NO), and nitrogen dioxides (NO2) and the termolecular reaction of hydroperoxy radicals (HO2) with NO2 greatly impact the atmospheric oxidation efficiency.
M. Rolletter, A. Hofzumahaus, A. Novelli, A. Wahner, H. Fuchs, H. Fuchs   +5 more
doaj   +1 more source

Scale dependence of the marine atmospheric boundary‐layer response to ocean surface‐temperature variability in the EUREC4$$ {\mathrm{EUREC}}^4 $$A region

Quarterly Journal of the Royal Meteorological Society, EarlyView.
With a minimal physics model and a high‐resolution fully 3D simulation, we demonstrate that the marine atmospheric boundary layer (MABL) response to sea‐surface temperature (SST) variability displays a dependence on the horizontal scales of motion.
Alessandro Storer, Matteo Borgnino, Claudia Pasquero, Agostino Niyonkuru Meroni   +3 more
wiley   +1 more source

Wavelet covariance approach to measure convective boundary‐layer structure

Quarterly Journal of the Royal Meteorological Society, EarlyView.
This study introduces a wavelet‐based framework that applies the Haar discrete wavelet transform (DWT) to radiosonde profiles of potential temperature and water vapor mixing ratio for diagnosing convective boundary‐layer (CBL) structure. The method objectively identifies key CBL parameters, including the surface‐layer height, entrainment zone depth ...
Song‐Lak Kang, Cho‐Rong Choi, Jung‐Hee Ryu   +2 more
wiley   +1 more source

EnKF and expectation‐maximization based parameter estimation of a convective gravity‐wave parameterization using Strateole 2 constant‐level balloon data

Quarterly Journal of the Royal Meteorological Society, EarlyView.
An offline methodology is applied to estimate parameters of a convective gravity‐wave scheme using momentum flux (MF) observations from constant‐level balloons (left panels: pdfs of east and west MFs in green from observations and black from EnKF). The approach integrates an ensemble Kalman filter with an expectation‐maximization algorithm and permits ...
F. Lott, P. Tandeo, M. Pulido, D. Bardet
wiley   +1 more source

Dynamics and thermodynamics of the fast and slow Madden–Julian Oscillation

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The results of this study highlight the MJO as a complex phenomenon, the behavior of which is driven by an interplay of thermodynamic and dynamic processes. The MJO's distinct speeds are controlled by different mechanisms: slow MJOs propagate eastward primarily via horizontal moisture advection, fast MJOs by vertical moisture advection.
Víctor C. Mayta, Ángel F. Adames Corraliza, Katharina M. Holube, Qiao‐Jun Lin   +3 more
wiley   +1 more source

Dry intrusions and warm‐core development in Medicanes: Insights from a multi‐case analysis and the peculiar evolution of Ianos

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Mediterranean tropical‐like cyclones show a clear seasonality, with September cyclones exhibiting the deepest convection and Ianos representing the most extreme case. While one or more dry intrusions are typically detected during the cyclone life cycle, Ianos instead features two much weaker descending airflows.
Daniele Nigro, Lorenzo Giovannini, Simona Bordoni, Stavros Dafis, Mario Marcello Miglietta   +4 more
wiley   +1 more source

The physical and synoptic‐dynamical differences between warm days, hot days, and heatwaves during summer in Victoria, Australia

Quarterly Journal of the Royal Meteorological Society, EarlyView.
During the day, there is composite mean cold advection in the boundary layer on warm days (WDs), hot days (HDs) and heatwaves (HWs). There is weaker surface‐sensible heating on HDs and HWs. A nocturnal jet advects warm air on HDs and HWs. There is a strong and slow‐moving upper‐level anticyclone on HWs.
Qinuo Huang, Michael J. Reeder, Christian Jakob, Malcolm J. King   +3 more
wiley   +1 more source