Global warming can be defined as changes observed in the temperature of air and ocean, melting of glaciers, and increasing average see level.1 Climate change will cause numerous variations in environmental and atmospheric factors including the amount of rainfall, humidity, and wind patterns, among other things. Transmission, distribution and incubation period of many diseases depend on many of these environmental factors. Not surprisingly, any changes in these factors may alter the virulence and epidemiology of many infectious and non-infectious diseases….

Since the mid-19th century, human activities have increased greenhouse gases such as carbon dioxide, methane, and nitrous oxide in the Earth's atmosphere that resulted in increased average temperature. The effects of rising temperature include soil degradation, loss of productivity of agricultural land, desertification, loss of biodiversity, degradation of ecosystems, reduced fresh-water resources, acidification of the oceans, and the disruption and depletion of stratospheric ozone. All these have an impact on human health, causing non-communicable diseases such as injuries during natural disasters, malnutrition during famine, and increased mortality during heat waves due to complications in chronically ill patients. Direct exposure to natural disasters has also an impact on mental health and, although too complex to be quantified, a link has even been established between climate and civil violence. Over time, climate change can reduce agricultural resources through reduced availability of water, alterations and shrinking arable land, increased pollution, accumulation of toxic substances in the food chain, and creation of habitats suitable to the transmission of human and animal pathogens. People living in low-income countries are particularly vulnerable. Climate change scenarios include a change in distribution of infectious diseases with warming and changes in outbreaks associated with weather extreme events. After floods, increased cases of leptospirosis, campylobacter infections and cryptosporidiosis are reported. Global warming affects water heating, rising the transmission of water-borne pathogens. Pathogens transmitted by vectors are particularly sensitive to climate change because they spend a good part of their life cycle in a cold-blooded host invertebrate whose temperature is similar to the environment. A warmer climate presents more favorable conditions for the survival and the completion of the life cycle of the vector, going as far as to speed it up as in the case of mosquitoes. Diseases transmitted by mosquitoes include some of the most widespread worldwide illnesses such as malaria and viral diseases. Tick-borne diseases have increased in the past years in cold regions, because rising temperatures accelerate the cycle of development, the production of eggs, and the density and distribution of the tick population. The areas of presence of ticks and diseases that they can transmit have increased, both in terms of geographical extension than in altitude. In the next years the engagement of the health sector would be working to develop prevention and adaptation programs in order to reduce the costs and burden of climate change.

Climate change is one of the most significant issues for researchers and media in recent decades. This phenomenon is slowly expanding whole over the world and affecting all relevant parameters. Hence, the main objective of this study is evaluating the impacts of global warming on minimum temperatures of Iran. To do so, daily minimum temperature of 47 synoptic stations were extracted during the 1961-1990. In order to investigate global warming impact, output of the HADCM3 model for 2015-2045 based on A2 and B2 scenarios was downscaling using SDSM model. Results illustrated that base on the relationship between predictor and predictable variables, created model between these variables are partially capable of producing climate data for future periods. Correlation coefficient (r) between observed and generated data during the 1976-1990 was 0.95. Furthermore, results of variance and correlation tests indicated that there is significant similarity between observed and generated data. Finally, the model demonstrated that minimum temperature in studied statins will be increased during 2015-2045. Temperature will be increased about 0.8 and 0.5oC based on the A2 and B2 scenarios, respectively. The stations will experience different temperature changes.

The 80s showed the world that the human environment has been so destroyed and the growth of the population and the ever-increasing increase in human production power have given such dimensions to this destruction that the habitability of the earth has been threatened and the lives of human beings have been endangered. The researches that took place in this decade and the huge changes that took place in the natural conditions of the earth indicated that the earth is warming. Global warming has brought drought, famine, and water scarcity. The cold and snowy winters of the past are no more. Summers have become hot and long, and also the amount of annual rainfall has decreased. This heat damages agricultural products and causes shortage of water needed for agriculture and drinking water. In addition, the increase in the earth's temperature has endangered the living conditions of many animal and plant species, and a large number of them have disappeared so far. This increase also includes the risk of melting polar ice and icebergs. If this happens, the sea level will rise. As a result, many coastal cities and low-lying deltas of the world will go under water, including the city of Miami in the United States of America and the delta of Bangladesh.

Population increasing and irregular Immigration to Tehran, which followed by developing construction, has been increased the hazard exposure of the city of Tehran. In addition, historical urban spreading of Tehran, and surrounding by the important active faults, increase the risk of earthquake consequence. After a destructive earthquake, a capital city such as Tehran encounters to fire, subsidence, water leakage and failure of many services. Earthquake early warning system as a solution of risk reduction has been proposed in recent decades. A limited number of countries such as Japan, America, Mexico, Romania, have almost applied this system and some countries such as Turky, Korea, China, and Italy are developing EEWS. This paper was conducted for examination of the possibility or impossibility of using the earthquake early warning system of Tehran. Consequently a feasibility study of theoretical network has been investigated. Also sensitivity analysis of some EEWS parameters has been done. Finally, according to the Tehran’s active faults, we concluded that it is possible to provide alarm time for many destructive earthquakes.