Global warmingIntroductionof global warming The average temperature of theatmosphere is determined by the concentration of the atmospheric gasesmolecules such as carbon dioxide, nitrous oxide and methane. The concentrationof these gases can be changed by various factors including human activities andlead to changes in climate and global warming.
The continuous burning of fossilfuels by human result in the rising of the concentration of carbon dioxide, which is known as the greenhouse gases as can allow the entry of sunlight into theatmosphere but not exit the atmosphere, leading to a gradual warming of theEarth’s atmosphere. About 160000 years ago, the average global temperature was5 degree Celsius lower that now. Scientists believed that the temperature willbe increasing at the rate of 0.3% per decade due to industrialization. Within40 years, the average temperature of the Earth would be raised by 1.5 to 5degree Celsius with the doubling of the carbon dioxide concentration from theindustries.
Causesof global warning High concentrations of greenhouse gases arethe main reason in causing global warming. Usually, they are important in thebalance of heat of atmosphere as they are able to absorb infrared radiations.First of all, radiant energy from the sun enters the Earth’s atmosphere. Somesolar radiation is reflected back to space. The Earth absorbed most of theradiation and warming the surface of the seas and lands. By this, infraredradiation ( heat ) is emitted by the surface and radiates back to space.However, much of the heat does not escape from the atmosphere but remainstrapped by the greenhouse gases, warming the atmosphere. They done this byabsorb some of the infrared energy and emit it back to the Earth’s surface ( Figure3.
0 shown in Appendices 3 ). Only little life would be survived as the Earth istoo cold without this process. However, small amount of these gases is enoughin preventing thermal radiation from radiating out of the atmosphere. In 1960,scientists at the Mauna Loa laboratory on Hawaii’s highest volcano start tomeasure the greenhouse gases concentrations in the atmosphere. This site ischosen as it acts as the Northern Hemisphere atmospheric conditionsrepresentative and is considered free from local airborne contamination.
Theannual lows and high of the carbon dioxide concentration is shown by the crestsand troughs of the graph. From the midline of the graph, we can conclude thatthe concentration is continuously increasing. (Figure 3.1 shown in Appendices 3 ) However, some scientist believed thatincreased in the concentration of will not result in global warming. As we know, is soluble in water and not all the will remain in the atmosphere. is not only absorbed bythe rivers, seas and oceans but also used by green plants during thephotosynthesis process.
Examples of the algal blooms in spring and the intakeof in the atmosphere by the leaves of the plantsduring daytime show the ways to eliminate in the air. Thus, it may seem beneficial inagricultural production but harmful to the environment. Ozone depletion is another cause ofglobal warming Gases such as chlorofluorocarbon, CFC that can easily be foundin air conditioners, refrigerator and aerosol cans depletes the ozone thatprotect the living organisms from harmful high energy ultraviolet radiation.
Besides, global warming is alsocaused by deforestation. Deforestation change the patterns of the land byconverting the forest to buildings , crops and land settlement.Examplesof climate changes due to global warming Scientists have foundthat data from weather stations and balloons, satellite and computer programsshow that the irreversible effects are on their way. The Earth is becomingwarmer and warmer. Paleoclimatological records show that millions years ago theglobal temperature is 5 degree Celsius colder than now. ( Figure 3.2 shown inAppendices 3 ) . There will be acooling of the stratosphere.
Global warming will cause changing in the rainfallpatterns. The polar ice caps and glaciers start to melt due to global warming. TheGlacier in the White Thunder Ridge has acompletely different view in 1941 and 2004. ( Figure 3.3 shown in Appendices 3). This can result in the rise in the sea levels. It is possible to rise18cm by 2030 and 58 cm by 2090. A rise in sea levels causes low-lyingareas to be flooded, alter coastlines and contaminate fresh-water supplies.
Oneof the examples is wet lands between Timbalier Island and Galliano LA aredisappearing because of the rising in sea levels. ( Figure 3.4 shown inAppendices 3 ). All of these will have effects in increased tidal range andestuarine salt- front intrusion and recession of wetlands and shorelines. Global warming willincreases the frequency of drought. In 2012,almost 81% of the United States isfacing drought due to climate changes. ( Figure 3.
5 shown in Appendices 3 ). Theland will become dry and infertile and this leads to a drop in crop yields. As aresult, the people will suffer from hunger. The probability of hurricanesoccurring will also increase. Besides, the high temperature will causes a greatevaporation of water. Knowing that water vapour is a greenhouse gases, furtherenhanced will increases the rate of precipitation of snow at poles. This willleads to the formation of polar ice sheets. Global warming will leads to the change in thewind direction and wind stress over the sea surface.
This affects thedistribution of species which may leads to extinction of species in certainregions as the changes in ocean currents and nutrient mixing zones.Effect of global warming on humansettlement Millions of people from the worldwho are living in low-lying coastal plains, sea-sides and islands would bedisplaced by the inundation as the sea levels are continuously rising from yearto year. Families in Kiribati have no chose but to live near marginal areas,facing the problems of the continuously rising of sea levels. ( Figure 3.6shown in Appendices 3 ).
Effect on human health Changes in thetemperature will bring lots of disease to human such as respiratory diseases,cerebrovascular and cardiovascular. The situation will be worst especially in theelderly, the very young and the chronically. Our body thermo-regulatory systemwill be overloaded by high temperature causing in frank heat-stroke.In United States, the doubled amount on carbon dioxide concentration hasresult in the death of 1150 to around 7400. From the result, most of the deathoccurs in the elderly. In the case of hat fever, the levels of troposphericozone are also the reason beside of the released of pollen. The changes inclimate also caused the long term effects on mental health. In 1972, 125 peopledied and around 4000 people to become homeless because of the collapsing dam inthe USA.
80% of the survivors were found that they are having trauma from thatincident. All of this can changes the change in the characteristics andbehaviour of a person and lead to depression and stress throughout their life.Almost all the children were facing development problems due to the incident.
Effect on animal behaviour andsettlement Rising in sea levels caused byglobal warming will result in the loss of settlement for animals. We could seethat see turtles are losing their nesting beaches especially in the Caribbeanbeaches. The period of hibernation varies, becoming longer or shorter and theeggs will be laid earlier compare to previous years. The migratory journey willbe affected due to global warming. Moreover, populations will also be displaceddue to the warming of the Earth surface.
In the late 1970s, polar bears areincreasingly food-stressed as the have longer fasting periodduring open-water season. The rising in sea levels will also endangered speciesthat are living in the water like whales and dolphin. Mediterranean monk seals start to appear in Egypt, Lebanon and Israelthat they have not been found before. This could be due to the need of raising their pups on a beach.Effect on plants Due to the large changes in theclimate, some plants may get benefit from that as the rate of the activities ofmicroorganisms living in the soil increases based on the journal NewPhytologist while some may experience bad effect as plants are moving to coolerregions. Increasing in the temperature and strong wind are beneficial forplants that used wind to spread their seeds or pollens, for an example,Taraxacum Mongolicum species.
Warmer temperature will stimulate growth rate butonly at the initial. The growth rate decreases as it increases will time. Asmention earlier, the hightemperature will causes a great evaporation of water resulting in the formationof the large root system to obtain sufficient water. Changes in the treestructure in the form of leaf structure, shape and size architecture of theroot system are obvious to be seen. Furthermore, due to the rising of the sealevels coastal species like Arctic and alpine species will now have nowhere togo and. They will be located between the living places of human and rising sealevels.
Plantswill be playing their roles as ‘sinks’ more frequently to reduce theconcentration of carbon dioxide.How much one has to pay Researchers have found that in 2.4million to 3.1 million jobs will be lost and 177 billion dollars to 318 billiondollars of gross domestic product will be reduced in order to reduce andstabilize one greenhouse gas carbon dioxide to 93% of 1990’s levels in USA. Ways to Ozone DepletionIntroduction of ozone and ozone depletion Ozone, (g) is a highly reactive pale-blue gas that found in thestratosphere of our atmosphere as the ozone layer.
Ozone layer is locatedbetween 17 km o 25 km above the surface of the Earth, so it is known as thehigh-level ozone. Ozone molecule with a penetrating odour is a combination ofthree atoms of oxygen. A stable oxygen molecule, is split by theultraviolet radiation or electrical discharge to form an ozone molecule.
(Figure 4.0 shown in Appendices 4). Hence, ozone in maintained by the action ofthe ultraviolet rays light on ozone.
Ozone layer acts in the role of shieldingorganisms from excessive ultraviolet radiation from the sun in the upper atmosphere.( high-level ozone )However, ozone will leads to the stunted growth in plants,asthma in living organisms and causes particular material to be corroded whenit is at the ground level( low-level ozone). Ozone depletion occurs when theozone layer is becoming thinner and thinner and more ultraviolet ray radiationis reached on the Earth.Causes of ozone depletion Ozone depletion can happened throughtwo ways, that is naturally and caused by human activities.
By natural, ozonemolecules will combine with the nitrogen oxide to form nitrogen dioxide. Then,nitrogen dioxide will bind with oxygen atom to form nitrogen oxide and oxygen.The used of refrigerator and air-conditioner by human will cause large amountof chlorofluorocarbon, CFC to be released into the environment.
This is becauseCFC is used as a coolant in both refrigerator and air-conditioner. The uses offire extinguishers containing halogenated hydrocarbon or halon and other ozonedepleter such as carbon tetrachloride and methyl chloroform will result in thethinning of the ozone layer. For most of the ozone depleters are made up ofchorine or bromine which is chemically stable compounds. The intenseultraviolet radiation will break those molecules once they are at the upperatmosphere. Ultraviolet radiation strikes a CFC molecule and causes a highlyreactive single chlorine radical to break away.
The free chlorine radicalcollides with an ozone molecule and combine with oxygen atom to form chlorinemonoxide and oxygen. When a free atom of oxygen collides with chlorinemonoxide, two oxygen atoms form a molecule of oxygen. The chlorine atom is thusreleased and free to destroy more ozone molecules. ( Figure 4.1 shown inAppendices 4). Besides, the use of the organic or inorganic fertilisers willalso causes the thinning of the ozone layer as they release nitrous oxide to theatmosphere which is also known as a type of the ozone-depleting chemicals. Theincreased number of vehicles such as cars, motorcycles, vans and buses on theroad also contribute to the release of nitrous oxide gases.
Researches haveshown that the 5 out of 100 per cent of the nitrous oxide is released by thevehicle and yet the number of people using vehicles to go working or schoolingdoes not show a decline but increase in number.Examples of ozone depletion in the world The extreme condition of ozonedepletion is forming a continent-size hole known as ozone hole over Antarctica.CFC is parts of the reason for the formation of the ozone hole. In 1989, thedepletion increases by 47% as compared to the 3% over the Artic.
It is believedthat the ozone will continued to deplete at a rate of 5% for every decades (Figure 4.2 shown in Appendices 4). A strong stratospheric wind will blowsaround the surface of the Earth during the Antarctic winter, resulting theStratosphere, over Antarctica to be separated from the rest of the atmosphere,to be extremely cold. As the result, ice cloud that is known as polarstratospheric clouds ( PSCs ) will be formed. They remove nitrogen dioxide thatwill leads to the removal of to stop and lead to the accumulation of chlorinemolecules. The equation will be : . When it is springtime, free chlorine atoms are formed due to the breakdown of chorine moleculesformed during winter time.
Thus, the ozone depleting reactions are continued.Every single chlorine radical is able to breakdown thousands of ozone moleculesbefore deactivate by a nitrogen dioxide, or a hydrocarbon.Although ozone depletion in Antarctica is getting worse than ozone depletion inArtic, people should take concerned on both of the regions. There is aninvestigation showing that the ozone layer is decreased over 29% in the Artic region.Effect of ozone depletion on human health 99.9% of the harming ultravioletradiation coming from the Sun is filtered by the ozone layer.
Thus thinning ofthe ozone layer will causes the prolonged exposure to the ultraviolet radiationby human. This can lead to higher risks for eye cataracts and sunburns, causesmutation that will result in skin cancer such as melanoma. The “ozone hole”that is found over Antarctica has increased the medical case of skin cancer inthe villagers. Effect of ozone depletion on human immune system The ultraviolet radiation is strongenough to weaken our immune system and our body abilities to resist theinfectious diseases. As a result, we will get sick easily and more frequently.
For an example, the weakening of the immune system due to the ultravioletradiation will result in the activation of herpersimples virus on the skin. Therate of getting the skin diseases such as leishmaniasis or leprosy will behighly increase as they are affected by the sell-mediated immune response. Therisk of getting ultraviolet light-related skin cancer will also be highincreased among the people who are immune-suppressed for organ transplant.Effect of ozone depletion on crop The depletion of the ozone allowingultraviolet radiation from the Sun reduces the nutrient contents and cropyields of plants such as soya beans and peas. The leaf cells and chlorophyllare damaged by the high intensity of the ultraviolet radiation result in thedecline in the rate of photosynthesis and therefore reducing the yield of thecrop. This causes the loss in food become uncountable.Effect of ozone depletion on food chain The high intensity of the ultravioletradiation will disturb the food chain.
It will kill microorganisms andphytoplankton that acts as the producer or that are at the bottom of the marinefood chain as ultraviolet radiation has a high penetration power up to twentymeters down the sea. As the phytoplankton are at the bottom of the marine foodchain, it will changes the amount of the production of the marine like thefishes, crabs, shrimp, prawns and much more. This will lead to the shortage ofthe food supply as most of the world population depends on it. The penetrationof the ultraviolet radiation does not only affect the marine food chain butalso affect the food chain on land. It causes mutation in living organisms andreduced in the number of population of the animals that feed on the marinelives such as fish.
the Antarctic organisms are badly affected as they are only having a lowtolerance for the ultravioletradiation.Effect of ozone depletion on climate of the Earth Ozone depletion will also lead to theincreased in the temperature of the Earth. The high intensity of the sunlightmay causes global warming and result in the melting of the polar ice caps andglaciers. Consequently, low-lying areas will be flooded and causedpeople to loss their habitats or homes, damaged of the furniture and lots ofloss. Time and lots of efforts are required to rebuild their homes causes themto spend extra expenses.Ways to prevent ozone depletion It is very important to maintain theamount of the chlorine at the normal range in the atmosphere.
To achieve this, wecan reduce the release of CFC. The hydrochlorofluorocarbon (HCFC) that is acompound consisting of hydrogen, chlorine, fluorine and carbon atoms and hydrofluorocarbon (HFC) that is acompound consisting of hydrogen, fluorine and carbon atoms are used to replaceCFC in order to prevent the thinning of the ozone layer. This is because these gases will breakdown inthe atmosphere and return to the Earth in the form of rainwater unlike CFCs. We can also release the amount of CFCby reducing the use of the air-conditioners.
Switch on the fan if the weatheris not so hot and always switch off the air-conditioners at home when we areaway from our home or when they are not in use or not necessary. We shouldavoid the habit of switching on the air-conditioners whenever we like but notbecause of the hot weather. In 1978, certain countries like theUnited States, Switzerland and Canada have made their move to ban the use ofthe CFCs as the aerosol products as they are aware of the consequent harmfuleffect that can bring to. Therefore to continue this effort, people around theworld should also avoid buying the aerosol propellants can contain CFCs.
Aswe know that the uses offire extinguishers containing halogenated hydrocarbon or halon that can leadsto the ozone depletion, so we can find a way to recycle it properly likethrough waste centres. We also must have the fully understanding on the ways torecycle it so that it is still useful without the ozone-depleting chemical. Besides, we should stop releasing the chemicalsthat can cause the ozone depletion. Usually, this type of chemical is fromagriculture. Therefore, the farmers must take note of the fertilisers that theyare using.
Fertilisers that release the nitrous oxide that will leads to thethinning in the ozone layer are reduced to their maximum. A suitable place forthe use of fertilisers should be created so that the loss of the nitrous oxideto the atmosphere is at its lowest. We can also ensure that the absorption ofthe nitrogen by the crops is at its maximum by observing and recording thesuitable timing to use the fertilisers. Nitrous oxide is also released fromthe vehicles. We can find that a family will be having two cars or more thanthat which are not necessary.
Therefore, we should practice carpooling or usepublic transport like LRT, MRT, monorails for transportation. For a destinationthat is near, we should just walk there or riding a bicycle to there. I believethat there is no need to travel a place by car if we can reach there in 5 to 10minutes by walking. Moreover, we should buy the things eitherfood or goods that are manufactured in our own country.
This is becausedifferent things that are on sale are produced from various countries. So, thefurther they are manufactured, the longer distance they have to travel. As aresult, the amount of the nitrous oxide that will be produced increases andthis lead to further depletion of the ozone layer.
As the saying goes a small step for aman, one giant leap for mankind. So, we should not only practice the methodsthat we can do but also advice our family members and friends to do so. Weshould encourage the people around us to do the same things to protect ourozone layer from depletion.
Proof that ozone hole over Antarctica is healing The latest news from NASA have giventhe first proof of the ozone layer is recovering. They have seen that theaction from the authorities and the action of banning the chemicals haveeffectively decreases CFC levels and help in the recovering of the ozone layer.( Figure 4.3 shown in Appendices 4) Therefore, these efforts that I mentionedearlier should be continued.