Increasing levels of anthropogenic aerosols in Asia have raised considerable concern regarding its potential impact on the global atmosphere, but the magnitude of the associated climate forcing remains to be quantified. Here, using a novel hierarchical modelling approach and observational analysis, we demonstrate modulated mid-latitude cyclones by Asian pollution over the past three decades. Re...

[1] The U. S. Navy Operational Global Atmospheric Prediction System (NOGAPS) daily analysis fields are used to study the African easterly waves to show how they impacted two tropical cyclones. Danielle and Earl (2004) formed approximately at the same time in the Atlantic. A three to eight day band-pass filter is applied to the daily global analysis fields to reveal the characteristics of the Af...

The present study considers a variety of cyclone developments that occur in an idealized, baroclinic channel model featuring full condensation heating effects over an ocean with prescribed sea surface temperature variation. The geostrophic basic-state jet is specified by the tropopause shape, and horizontal shear is included by specifying the meridional variation of zonal wind on the lower boun...

Résumé. Nous présentons une étude pour la prédiction des trajectoires de cyclones dans l’océan Atlantique Nord à partir de données issues d’images satellites. On y extrait des mesures de vitesses de vent, de vorticité, d’humidité (base JRA-25) et des mesures de latitude, de longitude et de vitesse de vent instantanée des cyclones toutes les 6 heures (base IBTrACS). Les modèles de référence à ce...

[1] The heavy winds associated with tropical cyclones generate strong upper ocean mixing. Recent studies suggest that this enhanced mixing significantly contributes to the ocean poleward heat transport, mainly due to a strengthening of the subtropical cells. A general circulation model is used here to show that whether the poleward heat transport is actually increased depends crucially on the l...

[1] The record of past tropical cyclones provides an important means to evaluate the hurricane hazard. Historical chronologies are a source of information about tropical cyclones prior to the modern era. Chenoweth (2006) describes an archive of 383 tropical cyclones occurring during the eighteenth and nineteenth centuries, largely before the official hurricane record. The present study demonstr...

the southern coasts of caspian sea is subjected to synoptic/mesoscale weather systemsranging from locally enhanced sea breeze formation and small local front systems to synoptic scale cyclones.this study presents climatology of cyclones over the southern coasts of caspian sea covering a ten year period1996-2005. altogether 57 cyclones were formed during the ten year period. anoticeable seasonal...

5 Developing wave packets associated with the extratropical transition (ET) of tropical cy6 clones and winter cyclones in the Western North Pacific (WNP) and Atlantic basins are 7 diagnosed observationally by compositing reanalysis data over a 32 year period. While the 8 development of winter cyclones amplifies a weaker wave packet moving through the mid9 latitude storm track, there is no indic...

We show that the frequency of summertime midlatitude cyclones tracking across eastern North America at 40–50 N (the southern climatological storm track) is a strong predictor of stagnation and ozone pollution days in the eastern US. The NCEP/NCAR Reanalysis, going back to 1948, shows a significant long-term decline in the number of summertime mid-latitude cyclones in that track starting in 1980...