• We are available for your help 24/7
  • Email: info@isindexing.com, submission@isindexing.com


Paper Details

Dynamics between Clear, Cloudy and All-Sky Conditions: Cloud Forcing Effects

Antero Ollila

Journal Title:Journal of Chemical, Biological and physical sciences
Abstract


The author has analyzed the dynamics of atmospheric changes between allsky, clear and cloudy sky conditions. The basis of analyses is the calculation of flux values at the balance states. The analyses depend essentially on the time constants of basic processes, which can be analyzed separately. Two time constants are based on the former research results, and three time constants have been developed and estimated in this study. The basic processes in dynamic analyses have been the very rapid changes in cloudiness and cloud temperatures, the rapid change in upward atmospheric long wave radiation caused by solar insolation change, the slow change in temperature of the land and sea, and the transient change in the atmosphere temperature. This transient atmospheric process has an essential role in explaining why the surface temperature increases when at the same time the cloud forcing decreases. The dynamic simulations reveal that in all cases, two rapid changes in the atmosphere can bring the outgoing long wave radiation at the top of the atmosphere almost exactly (a difference of 0% to 0.3%) to the observed pseudo-balance values of clear and cloudy skies. Pseudo-balance values for clear and cloudy skies are not very time-sensitive because the values stay within 1 W/m2 from one day to 13 days. According to the true energy balance values, the slightly nonlinear cloud forcing would be -0.56 Wm-2 per 1% increase in cloudiness and -0.1 C per 1% increase in cloudiness over the normal cloudiness range variation from 60% to 70%. According tothis study, the commonly used cloud forcing in the units of W/m2 yields effects that are about 40% too low for the long-term cloudiness changes. Cloudiness changes could alone explain the global warming.

Download