This analysis was conducted on 31 synoptic stations in Iran. Initially, the Mann-Kendall test was administered in order to analyse the trend of alterations of these two components over time and the results suggest that 16% of the stations show significant relationship with annual precipitation (positive and negative). More stations showed significant relationships between sunspots and minimum a...

This paper qualifies the effect of different convection schemes and center-domains on the simulation of winter precipitation over Iran using RegCM3 numerical climate model. It is compressible, finite difference with hydrostatic equilibrium in sigma coordinate with a semi-implicit algorithm for reduction of horizontal diffusion. Iran experienced two dry and wet periods during winters of 1997 and...

. introduction most of the warming over the last 50 years has been caused by emissions of carbon dioxide (co2) and other greenhouse gases due to human activities. observed changes in the climate due to increasing greenhouse-gas concentrations have made it essential to investigate these changes. the general circulation model (gcm) is the most current method of investigating climate change studie...

Statistical methodology is devised to model time series of daily weather at individual locations in the southeastern U.S. conditional on patterns in large-scale atmosphere–ocean circulation. In this way, weather information on an appropriate temporal and spatial scale for input to crop–climate models can be generated, consistent with the relationship between circulation and temporally and/or sp...

Atmospheric reanalysis products offer high-resolution and long-term gridded datasets that can often be used as an alternative or a supplement to observational data. Although more accessible than typical data deemed fit for climate change studies, show biases resulting from assimilation approaches. Thus, thorough evaluation of the product over region metric study is critical. Here, we evaluate p...

most scientists believe that the phenomenon of global warming occurred, however, in the case of the occurrence of this phenomenon by some environmental scientists have raised doubts. they are questioning global warming by arguing that the temperature recorded at the weather stations cannot be representative of the occurrence of the temperature rise. because with the passage of time and the incr...

1. introduction climate is a large system which is produced due to the relation and action between other large systems. if a change occurs in one of these systems, other systems will coordinate themselves with the change fast or slowly. the consequences of this coordination will impress the system that is starter of this change and an endless continuum of the links connects these systems togeth...