A Climatology of the Tropospheric Thermal Stratification Using Saturation Potential Vorticity

A Climatology of the Tropospheric Thermal Stratification Using Saturation Potential Vorticity

The condition of convective neutrality is assessed in the troposphere by calculating the saturation potential vorticity P* from reanalysis data. Regions of the atmosphere in which saturation entropy is constant along isosurfaces of absolute angular momentum, a state indicative of slantwise-convective neutrality, have values of P* equal to zero. In a global reanalysis dataset spanning the years ...

Mid-tropospheric Frontogenesis and Potential Vorticity

Mid-tropospheric frontogenesis is investigated for a case study in which special three-hourly rawinsonde data are available. Isentropic analyses are generated by objective means. Detailed machine isentropic trajectories lead to the three-dimensional description of the velocity field in space and time accompanying the frontogenesis. Ertel potential vorticity calculations serve as a check on traj...

Tropospheric ozone climatology over Beijing

Climatology of Sign Reversals of the Meridional Potential Vorticity Gradient over Africa and Australia

A 10-yr climatology (1986–95) was performed using ECMWF gridded analyses on isentropic surfaces to identify regions where the lower-tropospheric meridional potential vorticity (PV) gradient changes sign across Africa and Australia during their respective summer seasons. While an African sign reversal has been documented, no similar study has been performed for the Australian region, which also ...

investigation of thermal comfort properties of woven sport fabric using blend of estabragh fibers

امروزه لباس در نظر ورزشکاران و کسانی که برای اوقات فراغت خود و یا برای رسیدن به اندامی متعادل، ورزش می کنند؛ بسیار با اهمیت است. احساس مطلوب از لباس در زمره خصوصیات راحتی پوشش می باشد. خصوصیات انتقال رطوبت لباس، در ارزیابی راحتی حسی و حرارتی منسوجات تولید شده از آن ها بسیار مهم است. هدف از این تحقیق، معرفی پارچه جدید است که متشکل از الیاف استبرق با خواص منحصر به فرد می باشد. استبرق لیف طبیعی تو...