Global warming is the phenomenon that explains the rise in the temperature of the earth’s atmosphere and the oceans together with its projected continuation. Some of the leading causes of global warming include deforestation, traffic clogging of the urban areas, growth of unplanned urban settlements, and the use of Chlorofluorocarbons. Increased global warming is dangerous for the existence of life on earth. This is because the earth’s surface is heated in more direct way causing detrimental effects on the biota.
The last century witnessed the growth on the level of global temperatures i.e. from 0.5 degree Celsius since 1900 with the increase projected to occur at an alarming rate. According to Bily (2006), the year 1990 was the hottest in the last century while 1991 was the second warmest. This temperature increase has been caused by the rise in the level of green house gas concentrations emanating from human activities. It is projected that the earth’s temperature will most likely rise by 4.4°C in the next 100 years (Marsh and Svensmark, 2003). Temperature hike increases evaporation rate leading to more warming due to the build-up of excess of water vapor in the atmosphere. Other gases responsible for global warming include tropospheric ozone, nitrous oxide, Chlorofluorocarbons and methane. The impacts of the imbalance created by human activities are already being witnessed in the recent rise in intensity of natural disasters like as floods, landslides, drought and tsunamis.
warming has widely been attributed to numerous current natural systems. Some of the changes are detected in the context of the noted temperature changes with notable effects such as increase in the level of the sea and reduced levels of snow and ice. The rate of melting glaciers has witnessed a sharp rise in the recent surveys (Wang and Overland, 2009). The shrinking of the glaciers is a serious threat to the availability of drinking water. The melting of the glaciers contributes to the rise in the sea level. According to Wang and Overland (2009), partial deglaciation of the Greenland ice sheet in west Antarctic ice sheet contributes 13 to 29 feet rise in the sea level. Overall, the sea level due to melting glaciers has risen from 0.35 mm to 0.4 mm. scientists have cited the above proof to warn that most glaciers are in the verge of disappearance in a period of 15 to 25 years. According to Emanuel and Williams (2008), certain climatic events such as the 2003 European heat wave and the heat waves of Texas could never have happened without input from global warming. The earlier timing in the occurrence of the spring events and irregular shift in the abnormal plant ranges in terrestrial ecosystems is a product of global warming. According to the IPCC (2008), the future climatic changes are expected to hugely affect certain ecosystems such as tundra, coral reefs and mangroves. This will lead to the extinction of many animal and plant species as well as a reduced diversity of the ecosystems. The dissolved carbon dioxide causes acidification of water. Ocean acidification has increased with the recent prevalence in the level of global warming. The increase in ocean acidity decreases the concentration of carbonate ions used by most organisms in the food chains in making the structures required to survive. According to Honisch (2012), the current concentration of ocean acidification is higher than that of the past. Ocean acidification has been linked with Permian mass extinction that killed 95% of marine species. Conclusion Global warming is a real and ongoing phenomenon; it is not hype. Its current impacts are manifest in matters related to food security and habitat inundation. An urgent and collective strategy to avert global warming is required. An agreement was reached in the Kyoto Protocol in 1997 although little has been implemented to date (Bily, 2006). The most eminent preventive measure is the enhancement of public awareness on the