STUDY ON GLOBAL DIMMING GENERATED BY ATMOSPHERIC AEROSOLS

2013 ◽  
Vol 12 (4) ◽  
pp. 747-750 ◽  
Author(s):  
Marius Telisca
2016 ◽  
Vol 29 (11) ◽  
pp. 4229-4250 ◽  
Author(s):  
Kajsa M. Parding ◽  
Beate G. Liepert ◽  
Laura M. Hinkelman ◽  
Thomas P. Ackerman ◽  
Knut-Frode Dagestad ◽  
...  

Abstract Observations have revealed strong variability of shortwave (SW) irradiance at Earth’s surface on decadal time scales, referred to as global dimming and brightening. Previous studies have attributed the dimming and brightening to changes in clouds and atmospheric aerosols. This study assesses the influence of atmospheric circulation on clouds and SW irradiance to separate the influence of “natural” SW variability from direct and, to some extent, indirect aerosol effects. The focus is on SW irradiance in northern Europe in summer and spring because there is little high-latitude SW irradiance during winter. As a measure of large-scale circulation the Grosswetterlagen (GWL) dataset, a daily classification of synoptic weather patterns, is used. Empirical models of normalized SW irradiance are constructed based on the GWL, relating the synoptic weather patterns to the local radiative climate. In summer, a temporary SW peak in the 1970s and subsequent dimming is linked to variations in the synoptic patterns over Scandinavia, possibly related to a northward shift in the North Atlantic storm track. In spring, a decrease of anticyclonic and increase of cyclonic weather patterns over northern Europe contributes to the dimming from the 1960s to 1990. At many sites, there is also a residual SW irradiance trend not explained by the GWL model: a weak nonsignificant residual dimming from the 1950s or 1960s to around 1990, followed by a statistically significant residual brightening. It is concluded that factors other than the large-scale circulation (e.g., decreasing aerosol emissions) also play an important role in northern Europe.


1976 ◽  
Vol 37 (C6) ◽  
pp. C6-841-C6-844 ◽  
Author(s):  
B. KOPCEWICZ ◽  
M. KOPCEWICZ
Keyword(s):  

2017 ◽  
Vol 16 (10) ◽  
pp. 2381-2389 ◽  
Author(s):  
Sanda Voinea ◽  
Gabriela Manolache ◽  
Dimitrios Skliros ◽  
Sabina Stefan

1987 ◽  
Vol 52 (6) ◽  
pp. 1397-1406
Author(s):  
František Zrcek ◽  
Milan Horák

A model of remote detection of molecular air pollutants is devised based on the lidar equation. The various kinds of interaction of radiation with matter, viz. absorption, induced fluorescence, and Raman scattering, are taken into account; detection of either scattered or reflected signal is considered. The reflection is assumed to be either axial, using a retroreflector, or omnidirectional from a field target. Based on this model, an algorithm was set up for simulation of the different variants of the experiment, making allowance for a generally variable concentration of the compound along the optical pathway of the light beam. The basic atmospheric processes, viz. radiation absorption by the backround, heat emission, turbulence, and the effect of atmospheric aerosols, are treated, and the last of them is found to play the major role. Aerosols are looked upon as a source of the Mie scattering and they are described by distribution equations with respect to the particle size and the complex refractive index. The variable concentration of the aerosol along the optical pathway and the simultaneous effect of a higher numberof aerosol types are included.


Author(s):  
Hind A. A. Al-Abadleh

Extensive research has been done on the processes that lead to the formation of secondary organic aerosol (SOA) including atmospheric oxidation of volatile organic compounds (VOCs) from biogenic and anthropogenic...


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