Using NCEP–NCAR reanalysis data, decadal trends in planetary wave activity in Northern Hemisphere high latitudes (508–908N) in late winter and early spring (January–February–March) were studied. Results show that wave activity in both the stratosphere and the troposphere has been largely reduced and exhibits statistically significant downward trends since the 1980s. In the stratosphere, the wav...

The impact of teleconnections upon the surface climate has largely been examined via a response in monthly mean temperature or total precipitation. In this paper, a different approach is undertaken, by examining the response of synoptic weather-type frequencies to different teleconnection phases. For over 330 stations in the USA and Canada, the Spatial Synoptic Classification scheme has classif...

As part of a reanalysis of Galactic Asymptotic Giant Branch stars (hereafter AGB stars) at infrared wavelengths, we discuss here two samples (the first of carbon-rich stars, the second of S stars) for which photometry in the nearand mid-IR and distance estimates are available. Whenever possible we searched also for mass-loss rates. The observed spectral energy distributions extended in all case...

Extreme weather events such as ice storms cause significant damage to life and property. Accurately forecasting ice storms sufficiently in advance to offset their impacts is very challenging because they are driven by atmospheric processes that are complex and not completely defined. Furthermore, such forecasting has to consider the influence of a changing climate on relevant atmospheric variab...

Due to complicated interactions in the atmospheric environment, quantifying the influence of individual meteorological factors on local PM2.5 concentration remains challenging. The Beijing-Tianjin-Hebei (short for Jing-Jin-Ji) region is infamous for its serious air pollution. To improve regional air quality, characteristics and meteorological driving forces for PM2.5 concentration should be bet...

OBJECTIVES This study investigated the socio-demographic characteristics and medical causes of death among meteorological disaster casualties and compared them with deaths from all causes. METHODS Based on the death data provided by the National Statistical Office from 2000 to 2011, the authors analyzed the gender, age, and region of 709 casualties whose external causes were recorded as natur...

Historical fluctuations of North American snow extent from November through March are reconstructed back to 1900 using a combination of satellite and station observations. Using results of principal components analyses (PCA) from a companion study (Frei, A. and Robinson, D.A. Int. J. Climatol., this volume), simple and multiple linear regression models are used to take advantage of the spatial ...

In the past 18 years, our knowledge of that particular class of oceanic planetary waves also known as Rossby waves has improved significantly. Before the advent of altimetry they were already an important dynamical concept with a good theoretical understanding, but supported by very few, sparse observations; now they are a well-documented phenomenon, recorded in many different parameters in all...

A reanalysis is made for the helium abundance determination for the Izotov-Thuan (2004) spectroscopic sample of extragalactic H II regions. We find that the effect of underlying stellar absorption of the He I lines, which is more important for metal poor systems, affects significantly the inferred primordial helium abundance Yp obtained in the zero metallicity limit and the slope of linear extr...

Equatorial long-wave theory applies where a small horizontal aspect ratio between meridional and zonal length scales is assumed. In an idealized setting, the theory suggests that (i) meridional wind is small, (ii) geostrophic balance holds in the meridional direction, and (iii) inertio-gravity waves are small in amplitude or ‘‘filtered out.’’ In this paper a spectral data analysis method is use...