Results 51 to 60 of about 2,567 (220)

A Synoptic Analysis of Cyclonic Activity During 1961-2003 [PDF]

مخاطرات محیط طبیعی, 2012
Mid-latitude cyclones play an important role in precipitation over Iran. A survey on 6-hourly geopotential height of 1000 hPa level showed that the number of cyclones in the studied area reveals a positive trend.
Seyyed Abolfazl Masoodian
doaj   +1 more source

Exceptionally poor and good medium‐range forecasts of the large‐scale circulation over Europe in ERA5 reforecasts

Quarterly Journal of the Royal Meteorological Society, EarlyView.
This study investigates year‐round exceptionally poor and good day‐6 forecasts of the 500‐hPa geopotential height field over Europe using 45 years of ERA5 reforecasts and applies a weather regime perspective to analyse large‐scale pattern evolution and regime transitions.
Seraphine Hauser, Steven M. Cavallo, Linus Magnusson, Jonathan E. Martin, David B. Parsons   +4 more
wiley   +1 more source

Covariance of the intertropical discontinuity and African easterly jet in Sahelian wet and dry years

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Intertropical discontinuity and African easterly jet (AEJ) positions are strongly correlated, with a more pronounced linear relationship across wet years. Surface heat flux anomalies modify low‐level temperature and sensible heat flux gradients that shift the AEJ core south of the gradient maxima in both composites.
Marian Amoakowaah Osei, Cornelia Klein, Christopher M. Taylor, Douglas J. Parker, Michael Baidu   +4 more
wiley   +1 more source

Assessing the role of urban blue space in summer outdoor thermal regulation in northwestern Europe: A hectometric Weather Research and Forecasting modelling on idealized urban landscape

Quarterly Journal of the Royal Meteorological Society, EarlyView.
Using hectometric Weather Research and Forecasting simulations, we examine how urban blue spaces mitigate extreme summer heat in northwestern European cities through neighbourhood‐scale cooling mechanisms. Results show horizontal advection dominates cooling by mixing cooler air from waterbodies with warmer urban air, providing ∼50W·m−2$$ \sim 50\kern0 ...
Xuan Chen, Srinidhi Gadde, Arjan Droste, Gert‐Jan Steeneveld, Miriam Coenders‐Gerrits, Remko Uijlenhoet   +5 more
wiley   +1 more source

Almost Everything You Always Wanted to Know About Representing Gravity in Global Models but Were Afraid to Ask

Journal of Advances in Modeling Earth Systems
For over 60 years, an approximation involving spherical geopotentials has underlain the representation of gravity in global numerical models of Earth's atmosphere and oceans. This article explores how departures from sphericity can be allowed by assuming
Andrew Staniforth, Andy White
doaj   +1 more source

Large-scale circulation features associated with the heat wave over Northeast China in summer 2018

Atmospheric and Oceanic Science Letters, 2019
In late July and early August 2018, Northeast China suffered from extremely high temperatures, with the maxium temperature anomaly exceeding 6°C. In this study, the large-scale circulation features associated with this heat wave over Northeast China are ...
Panhong TAO, Yaocun ZHANG
doaj   +1 more source

Assessing high‐resolution numerical models and bottom‐boundary factors for a Mediterranean heavy precipitation event

Quarterly Journal of the Royal Meteorological Society, EarlyView.
State‐of‐the‐art, convection‐permitting NWP models reproduced the main features of the October 22–23, 2019 heavy precipitation event in Catalonia. However, slight configuration changes yielded varying streamflow responses and statistical performance, highlighting the challenge of simulating these events in Mediterranean medium‐sized basins ...
D. Ramonell, D. S. Carrió, A. Amengual, R. Romero   +3 more
wiley   +1 more source

Spatial and temporal variability of wet spells and their role in wet and dry summers and winters in Australia

Quarterly Journal of the Royal Meteorological Society, EarlyView.
The change in the frequency of wet spells in tropical Australia in summer primarily contributes to the change in precipitation between wet and dry years. In the extratropics, both the frequency and intensity of wet spells are important, especially in winter.
Sunil Pariyar, Christian Jakob, Michael Barnes, Martin Singh, Michael Reeder   +4 more
wiley   +1 more source

The non‐hydrostatic option of the ECMWF global weather forecast model: Improvements for kilometre‐scale modelling

Quarterly Journal of the Royal Meteorological Society, EarlyView.
This study presents improvements to the non‐hydrostatic version of the European Centre for Medium‐Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS), enabling stable global simulations at 1.4‐km resolution. A systematic comparison with the hydrostatic version at resolutions from 9 to 1.4 km shows that non‐hydrostatic effects emerge in ...
Jozef Vivoda, Inna Polichtchouk, Michail Diamantakis, Filip Váňa   +3 more
wiley   +1 more source

Evaluation of aerosol loading and its relationship with geopotential height in Nigeria’s Guinea Coast

Bulletin of the National Research Centre
Climate variability and atmospheric changes significantly affect weather patterns and human activities. Aerosols impact the Earth's climate by influencing cloud formation, scattering radiation, and cooling the planet. However, aerosols, like black carbon,
Onyinyechi Caroline Ibe, Okechukwu Kelechi Nwofor, Ugochukwu Kingsley Okoro   +2 more
doaj   +1 more source