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Here is a term paper on the ‘Effects of Climate Change’ for class 9, 10, 11 and 12. Find paragraphs, long and short essays on the ‘Effects of Climate Change’ especially written for school and college students.
Term Paper # 1. Melting of Ice and Sea Level Rise:
One of the many warning signals of global warming is the change in the ice caps due to melting, thinning, shrinking, retreating, freezing and disappearing. Satellite images have shown that the parts of our planet that are covered in snow each winter have decreased by 10 per cent. The snows of Kilimanjaro have melted more than 80 per cent over the last 100 years and will vanish by 2020.
Settlements in mountain regions are at enhanced risk of floods caused by melting glaciers. Spiti River, a high altitude Himalayan river located in the western Himalayan region, the annual snowmelt run-off, glacier melt run-off and total stream flow increase linearly with increase in temperature, but the most prominent effect of temperature increase has been noticed on glacier melt run-off.
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The ice covering parts of Greenland is already melting and may cause up to 7 meters of sea level rise. From 1980-2000 AD, the average annual temperature of the Arctic region has increased by 4°C, and as a result, the thickness of the ice sheets has decreased by 40 per cent.
The melting ice also can wash away the algae of the arctic region and can affect the food chain. The melting of ice, in turn, is changing the hydrological cycles and is also affecting the ocean currents. The flow rate of Atlantic circulation has dropped by 6 million tons of water per second from 1957 to 1958.
In the past century, sea level rise has occurred at a mean rate of 1.8 mm per year and the IPCC (2007) report suggested that sea levels would rise by between 190 mm (7.5 inches) and 590 mm by the end of this century. One meter sea level rise can flood up to 75 per cent of the dry lands of Maldives in the Indian Ocean and Marshall islands of the pacific, and can make these place uninhabitable (IPCC, 2007).
Many island nations of the Pacific, notably the Polynesian islands of Tuvalu, which based on more severe flooding events in recent years, was thought to be “sinking” due to sea level rise. Sea level rise could also displace many shore-based populations; it is estimated that a sea level rise of just 200 mm could create 740,000 homeless people in Nigeria. Many small islands have poorly developed infrastructure and limited resources, and often small island populations are dependent on marine resources to meet their protein needs. So, climate change could completely change the social and economic conditions of the islands.
The IPCC report of 2007 estimated that accelerated melting of the Himalayan ice caps and the resulting rise in sea levels can increase the frequency of floods in the short-term during the rainy season and can greatly magnify the impact of tidal storm during the cyclone season. A sea-level rise of just 400 mm in the Bay of Bengal would put 11 per cent of the Bangladesh’s coastal land under water, and can create 7 to 10 million “climate refugees”.
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Recent report suggests that 45 cm rise in sea level (likely by the end of the 21th century), combined with other forms of anthropogenic stress on the Sundarbans, and could destroy 75 per cent of the Sundarbans mangroves (UNESCO, 2007). Already, Lohachara Island and New Moore Island/South Talpatti Island have disappeared under the sea, and Ghoramara Island is half submerged. Low island mangroves are most at risk, as demonstrated in Bermuda, where sea level rise has exceeded peat accumulation rates periodically, resulting in landward the back of mangrove stands.
Climate change may reduce global mangrove area by 10-15 per cent. Direct climate change impacts on mangrove ecosystems are likely to be less significant than the effects of associated sea level rise. Rise in temperature and the direct effects of increased CO2 levels are likely to increase mangrove productivity, change the timing of flowering and fruiting, and expand the ranges of mangrove species into higher latitudes.
Changes in precipitation and subsequent changes in aridity may affect the distribution of mangroves. Sea level rise will also destroy about 40-50 per cent of the world’s coastal wetlands by 2080. A World Bank report concluded that human activities in the deltas can cause the areas to sink much faster than any predicted rise to sea level, thus can increase their vulnerability to storms and floods.
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Sea level rise in the Nile delta can change the water quality, can affect many freshwater fishes, can increase the salinity of the groundwater and also can inundate the fertile agricultural lands. Rising sea levels will threaten coastal aquifers. Many of India’s coastal aquifers are already experiencing salinity ingress including Saurashtra coast in Gujarat and Minjur aquifer in Tamil Nadu.
Increasing frequency and intensity of droughts in the catchment area will lead to more serious and frequent salt-water intrusion in the estuary and thus can deteriorate surface and groundwater quality. Some scientists suggest that climate change may alter the physical characteristics of aquifers themselves.
Higher CO2 concentrations in the atmosphere may change carbonate dissolution and can promote the formation of crust, which in turn may negatively affect infiltration properties of topsoil. Due to melting of ice sheets, there will be an increase in the frequency of floods in the rivers of India originating from Himalayas.
Term Paper # 2. Effects on World’s Water Resources:
A warmer climate will accelerate the hydrological cycle; can alter the intensity and timing of rainfall Warm air can hold more moisture and can increase evaporation of surface moisture, which in turn can intensify rainfall and snowfall events. So, intensity of flood will also increase. If there is deficiency of moisture in the soil, solar radiation will increase the temperature, which could contribute to longer and more severe droughts.
In a number of studies, it has been proved that global warming and decline in rainfall may reduce net recharge and can affect groundwater levels. Decrease in winter precipitation would reduce the total seasonal precipitation being received during December-February, and can impose greater water stress. Intense rain for few days will result increased frequency of floods and the monsoon rain would also be lost as direct run-off, thus can decrease the groundwater recharging potential. Increased rainfall amounts and intensities will lead to greater rates of soil erosion.
Changed freshwater inflows into the ocean will lead to changes in turbidity, salinity, stratification, and nutrient availability, all of which affect estuarine and coastal ecosystems. The status of present precipitation and a rise in temperature by 4°C caused a decrease in run-off by 2-8 per cent, depending upon the areas considered and the model used. The river basins of central India, located in a comparatively drier region, are more sensitive to climate change.
Climate change will affect the Indian River basins significantly. River basins of Mahi, Pennar, Sabarmati and Tapti shall face water shortage conditions. On the other hand, river basins belonging to Godavari, Brahmani and Mahanadi shall not face water shortages, but severity of flood shall increase in these areas. A change in field-level climate may alter the need and timing of irrigation. In India, roughly 52 per cent of irrigation is dependent on groundwater use. So, it can be an alarming situation with decline in groundwater and increase in irrigation requirements due to climate change.
By the mid of the 21st century, annual average river runoff and water availability will increase by 10-40 per cent at high latitudes and in some wet tropical areas, and decrease by 10-30 per cent over some dry regions at mid-latitudes and in the dry tropics, some of which are presently water-stressed zones. There will be an increase in drought affected areas and the frequency of heavy precipitation will increase, which, in turn, will increase flood risk.
Term Paper # 3. Effects on Human Society and Health:
IPCC reported that increased global temperature will increase the death rate. Higher temperatures will likely increase the concentration of ozone in troposphere that will contribute to cardiovascular and pulmonary illness (IPCC, 2007). Global warming may create favorable conditions for vectors conveying infectious diseases like dengue, malaria, etc. Disease vectors such as mosquitoes, ticks, and flies may occur in greater numbers over longer periods during the year.
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As northern Europe becomes warmer, ticks, which carry encephalitis and Lyme disease and sand flies, transmit visceral leishmaniasis are likely to move in. Endemic morbidity and mortality due to diarrheal disease primarily associated with floods and droughts are expected to rise in east, south and Southeast Asia due to projected changes in the hydrological cycle associated with global warming. Diarrheal diseases and outbreaks of other infectious diseases (e.g., cholera, hepatitis, malaria and dengue fever) have been reported to be influenced by climate-related factors.
There is a strong correlation between increase in sea surface temperature and sea level and the annual severity of cholera epidemics in Bangladesh. Warmer sea-surface temperatures of south and Southeast Asia would support higher phytoplankton blooms, which are excellent habitats for survival and spread of infectious bacterial diseases such as cholera.
In general, increased warmth and moisture will enhance transmission of diseases. Mathematical models proved that by 2080, the potential exposure of people by mosquitoes could increase by 2-4 per cent. An empirical model projected that the population at risk of dengue fever will be larger in India and China.
Several studies have confirmed and quantified the effects of high temperatures on common forms of food poisoning, such as salmonellosis (IPCC, 2007). The methylation of mercury and its subsequent uptake by fish and human beings will increase due to climate change.
A large number of deaths due to heat waves-mainly among the poor, aged people and labourers such as rural daily wage earners, agricultural workers and rickshaw pullers have been reported in Andhra Pradesh, Orissa and elsewhere in India during the past five years.
Exposure to heat can be a significant risk factor for cerebral infarction and cerebral ischemia during the summer months. The combination of air pollutants and allergen production linked to climate change may enhance allergic disease and asthma incidences in vulnerable individuals, especially children, infants, and asthmatics.