Results 81 to 90 of about 7,657 (248)
The impact of dehydration and extremely low HCl values in the Antarctic stratospheric vortex in mid-winter on ozone loss in spring [PDF]
Atmospheric Chemistry and PhysicsSimulations of Antarctic chlorine and ozone chemistry in previous work show that in the core of the Antarctic vortex (16–18 km, 85–55 hPa, 390–430 K) HCl null cycles (initiated by reactions of Cl with CH4 and CH2O) are effective.
Y. Zhang-Liu +11 more
doaj +1 more source
Quarterly Journal of the Royal Meteorological Society, EarlyView.We document the protocol and first results from the first ever coordinated multimodel variable‐resolution experiment set with refinement over the polar regions. We find that the refinement generally yields model‐dependent effects. The most consistent improvement is an amelioration of the upper‐level cold bias in the polar regions that translates into ...
Lise Seland Graff +8 more
wiley +1 more source
Exploiting Aeolus winds in a regional numerical weather prediction model
Quarterly Journal of the Royal Meteorological Society, EarlyView.Aeolus measured winds have proven to be beneficial for global models. However, demonstrating positive impact for limited‐area models has been a challenge so far. For the first time, we have demonstrated a statistically significant positive impact of Aeolus winds in a limited‐area model by using the 4DVar data assimilation technique and the most recent ...
Gert‐Jan Marseille +3 more
wiley +1 more source
Quarterly Journal of the Royal Meteorological Society, EarlyView.The climatological‐error covariance matrix used in three‐dimensional variational data assimilation (3DVar) provides smooth and isotropic increments spread to long distances. In contrast, three‐dimensional ensemble variational data assimilation (3DEnVar) with a purely ensemble‐error covariance matrix provides inhomogeneous increments and contains the ...
Kaushambi Jyoti +3 more
wiley +1 more source
Forecast‐Error Diagnostics in Neural Weather Models
Quarterly Journal of the Royal Meteorological Society, EarlyView.Deep learning weather prediction models enable efficient forecast‐error diagnostics through auto‐differentiation and low computational cost. We apply grid‐point relaxation and gradient‐based error sensitivity to identify key forecast‐error sources. Results show that medium‐range forecasts in the midlatitudes benefit most from relaxing the stratosphere ...
Uroš Perkan +2 more
wiley +1 more source
Global-scale gravity wave analysis methodology for the ESA Earth Explorer 11 candidate CAIRT [PDF]
Atmospheric Measurement TechniquesIn the past, satellite climatologies of gravity waves (GWs) have initiated progress in their representation in global models. However, these could not provide the phase speed and direction distributions needed for a better understanding of the ...
S. Rhode +9 more
doaj +1 more source
Epistemic and aleatoric uncertainty quantification in weather and climate models
Quarterly Journal of the Royal Meteorological Society, EarlyView.Aleatoric and epistemic uncertainties over time on weather and climate time‐scales, estimated through ensembles that sample aleatoric and epistemic uncertainty using Bayesian neural networks for parameterisations in the Lorenz 1996 model. The spread shows the 16th and 84th percentiles.
Laura A. Mansfield +1 more
wiley +1 more source
Ensemble reliability and the signal‐to‐noise paradox in ECMWF subseasonal forecasts
Quarterly Journal of the Royal Meteorological Society, EarlyView.We derive a general expression for the ratio of predictable components (RPC) in terms of correlation, spread–error ratio, and total variance ratio. Physical constraints on the admissible solutions (i.e., real‐valued and non‐negative variances) provide a mechanism to identify statistically paradoxical sample combinations of reliability and correlation ...
Christopher D. Roberts, Frederic Vitart
wiley +1 more source
Stratospheric Ozone and Health [PDF]
International Journal of Epidemiology, 1994 Stratospheric ozone is being depleted and ambient ultraviolet (UV) irradiance is probably increasing. While remedial steps have been taken through the Montreal protocols, at best it will take some 90 years for stratospheric ozone concentrations to return to the levels existing in the 1970s.The evidence that these changes may have harmful effects on ...
openaire +2 more sources
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 +9 more
wiley +1 more source