the present research focuses on the changes of urmia lake level. for this purpose, two timescales have been considered. the trend changes of temperature, precipitation rate and quantitative values of climate type for the observational period from 1968 to 2011 (past scale) and from 2011 to 2100 (future scale) have been analyzed. general circulation model (gcm) is considered for simulating the va...

One of the most important Limitation General Circulation Models , Large scale are being simulation of climatic variables. So should With Various method are downscaled, The ability to have identified a study area. Choose a suitable GCM model for the study area Very important role In the simulation  parameter (precipitation) is intended for future. In this research of CMIP5 Models Contains BCC-CS...

because of low spatial resolution and simplifications in meteorological processes in global circulation models, they cannot sufficiently simulate the weather, comparing to the regional models; then, spatial and temporal downscaling of the gcm outputs are needed for decreasing errors of the global circulation models. there are two methods of downscaling: statistical and dynamic. weather generato...

Climate change is found to be the most important global issue in the 21st century, so to monitor its trend is of great importance. Atmospheric General Circulation Models because of their large scale computational grid are not able to predict climatic parameters on a point scale, so small scale methods should be adapted. Among downscaling methods, statistical methods are used as they are easy to...

Randall et al. (1996) summarized a strategy for testing parameterizations in single-column models (SCMs). The SCM is driven with observations and the results produced by the SCM are compared with additional observations of the same meteorological events. When the SCM’s parameterizations are judged to have performed satisfactorily in tests against observations, they can be transplanted into a th...

Scientists have long been aware there is a need for a stochastic description of radiative transfer through media with statistically distributed parameters (Stephens 1984; Ramanathan et al. 1989; Stephens et al. 1991). This study used a shortwave stochastic band model to investigate radiative transfer through a broken cloud field for several days when low-lying fair-weather cumulus and cumulus f...

While considerable advances in the understanding of atmospheric processes and feedbacks in the climate system have led to a better representation of these mechanisms in general circulation models, the greatest uncertainty in predictability of future climate arises from clouds and their interactions with radiation. To explore this uncertainty, the cloud resolving model has evolved as one of the ...

abstract due to low spatial resolution or simplifying of some micrometeorological phenomena, atmospheric general circulation models are not able to give a good estimation for weather conditions over study area. so their outputs should downscale into weather stations scales. in this research data of hadcm3 downscaled by using lars-wg5 with three scenarios, confirmed by ipcc including a1b, a2 and...