Introduction The result of rapid urbanization, industrialization made in the name of development has created a number of disastrous consequences in front of us. These disasters appears among us sometimes as pollution, sometime acid rain and now Climate change as the summation of all these environmental hazards, producing vast alternation in the environmental and natural phenomena. Climate change, a big environmental threat and challenge of our generation has created several signals of disturbances in different aspects of life present in this planet. Climate change, result of immoral deeds of human is presenting its pressure to human and other forms of life equally although merely human actions are responsible for inviting climate change. Thousands of green writer describes this menace using different languages keeping the central theme same. Their discoveries and opinion about climate change and its impacts can be read in newspapers, books, online magazines etc. However this paper is presenting a fresh but relevant topic which is the impact of climate change on monuments and building structures. Along with the speedy industrialization and urbanization, people are spending heap of coins for the construction purpose which involves the construction of buildings, monuments, bridges, culverts, roads, etc .These structures are erected taking the local environment and temperature under consideration. These structures should match the local environmental condition otherwise it results into failure. Because of these reasons different types of construction can be witnessed in the different geographical regions of varying environmental factors. We see different figures of constructions if we visit different places but almost same type of constructions in a same area. Causes of monuments and building Deterioration In this era , climate change( global warming) has emerged as a global environmental threat. So there is no any surprise that scientists would be interested to understand how climate change impacts on concrete from which our infrastructures are made. Concrete deterioration occurs by variety of stimuli including physical, chemical and mechanical factors. Among the various ,the major two cause of deterioration are carbonation and chloride penetration. Carbonation occurs when atmospheric CO2 penetrates the concrete structures and exposes steel reinforcement (makes the attachment of concrete and rod more fragile) .Similarly, chloride penetration causes cracking and peeling of various layers of these structures. However the time for corrosion depends on their location and level of exposure to the environment. Durability of concrete structures depends heavily on the manner in which they are constructed, material used as well as the environmental condition they are routinely exposed to. Similarly, climate change also badly affects our historical, cultural heritage, which were specially made up of natural stones. In the present situation, we all are familiar with the increasing global temperature which rapidly heats the outer layers of these monument building?s stones(non conductors) while the inner layers of the same stone is heated very slowly. Due to this vast temperature difference ,unequal expansion and contraction among the various layers of stone results in peeling of stone, cracking of it resulting in pore formation and finally leads to the damage of monument. This process is heavily supported by the temperature difference observed in day to night, summer to winter .This increasing temperature may cause high dryness in the stone and alters the chemical composition of the stone making it more fragile and brittle .This dryness may result in conversion of gypsum to anhydrite as follows, CaSO4.2H2O into CaSO4+H2O Due to raise in percentage of CO2 in atmosphere, CO2 gets transformed into carbonic acid(H2CO3) when it comes in contact with atmospheric moisture. Thereafter, carbonic acid thus formed interacts with basic mineral components of stones and transforms them into soluble salts leading to damage of stone structures. Both of these corrosion mechanisms are influenced by climate change. The story doesn?t ends here. Due to climate change mutable wind pattern is often seen .High air speed is often observed, large dust particles including sand particles are blown and acts like a mobile Saw and erodes monument and their surface. Also the amount of atmospheric SO2 is increasing due to increasing traffic intensity , industrial activities, etc. Conversion of SO2 into SO3 takes places when water vapor acts upon SO2. and H2SO4 is formed as the final product. This final product acts upon salt component of stone and changes into calcium sulphate. Likewise, Sulphur dioxide(SO2)and Nitrogen dioxide(NO2 ) are produced during the combustion of fossil fuel as gas,coal,oil for power generation. Nitrogen dioxide(NO2) in the presence of water converts into nitric acid which transforms calcium carbonate present in stone and rocks into calcium nitrite. Similarly, artificial aerosols which consists of fine carbonate particles, organic compounds as hydrocarbon, aldehyde, tars deposits on the surface of monuments and makes the outer appearance of the monuments/building black that looks ugly. This is often seen in old religious and cultural heritages of Nepal and India also. The live example of it can be found in Taj Mahal which is recorded to be badly affected by so2. Similarly ,Giza, where most important Egyptian monuments and historical places are found are also noted to be suffering from these adverse climatic factors. Conclusion Monuments are the treasure of every nation and the protection of them is the responsibility of every wise citizens. These wealth transfers the information of ancient life styles, culture, religion to the future generation. So we must be aware about the monument deterioration. Due to this climate change it is sure to raise the cost of building and monument construction . One has to spend more for making a better home which suits the rapidly changing climatic factors .Above mentioned facts proves that the prevailing construction materials are less durable for the future if the climate changes in same pattern. References 1) Research report of CSIRO climate change flagship Australia. 2) Wikipedia 3)S.M.Robaa/ICEHM 200,Cairouniversity,Egypt,September,2000.Pase 187-200
|
4 Comments
Welcome fren Kehkashan Basu
Posted 03-11-2012 14:06
Thanks for sharing this ,Dhiroj.
Posted 03-11-2012 13:59
Yes Nar Bahadur, climate change is affecting every form of our life...........Think green............do green................go green.............life make green to combat climate change
Posted 03-11-2012 10:54
Oh very sad! Climate change is the real threat and affecting all forms of life and infrastructures. very sad to know this..............
Posted 03-11-2012 10:46