Climate change in Iran and the world is considered by most scientists to be due to the emergence of “greenhouse” state that will have adverse effects on the Planet from different viewpoints. Due to human interference in climate change, undeniable climate change has been asserted in various world reports and the latest statements by the International Community, but scientific doubts also exist on reasoning behind climate change reported by “CHANGEINTERGOVERNMENTALPANELONCLIMATE”. As BRYSON (1977) states, surge from one pattern to another might change the climate of some of the mid-range-latitude areas drastically, and it is very likely to create a “drought-or-flood” pattern. The increase in temperature in some of Iran's meteorological stations indicates a tendency towards arid climate, and probably the period of climate change has begun in the country of Iran. The country, according to the research, has a pattern of a number of years of droughts alternated by a number of rainy years. Environmental problems such as global warming, frequent occurrence of droughts, expansion of deserts and the increasing trend of desertification, increasing number of forbidden areas for the extraction of water and occurrence of destructive floods have caused ecological instability in the country and have increased the vulnerability of the country's natural resources.