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The average temperature of the earth in general is not stable but varies with time, as proved through analyses of the earth’s geological layers Our planet was colder for example by about ten degrees 20,000 years ago, during the peak of the last glacial period. Changes in temperature are nevertheless very slow to occur; the temperature of the earth fluctuated by 0.2 degrees between 1,000 AD and the end of the 19th century. However, at present, the rate of change in temperature is increasing. This is causing great concern amongst the international community as temperature is rising at an accelerating rate. Since the end of the 19th century, over hardly one hundred years, the average temperature of the earth has increased by 0.6 degrees. What is worse is that analyses using computer simulations seem to indicate that the warming of the earth is going to continue accelerating and that the average temperature could consequently increase by 1.4 to 5.8 degrees by the end of the 21th century. It is this phenomenon which we call global warming.
Virtually everyone is a stakeholder when it comes to the warming of the earth, because if global warming has not already affected our lives, sooner or later it will. Global warming affects and will affect every person on this earth. However, animals are the most negatively affected party in this issue as global warming is a consequence of human behaviour. Global warming melts glaciers and increases sea levels. This has been linked to the disappearance of some animals such as the polar bear and the auk. In addition, due to the increase in sea levels some regions have been flooded while others will be if temperatures continue to rise. Global warming will also entail an increase of temperature in some regions of Europe. The increase in temperatures has not been uniform across the planet; temperature changes vary with regions.
Nowadays, more and more species are becoming endangered. If we do not change our behaviour and make efforts to stem global warming, many species will disappear.
Species affected by global warming include:
• Polar bears
Due to global warming, there are now only 20,000 polar bears, mostly in Canada. Of 19 species of penguins, 11 are under threat of extinction, and at least 18 of 22 species of Albatross are endangered. In the North Pole, the increase in the average temperatures over the last ten years has been twice as fast as the average increase in temperatures in other parts of the world. The temperatures on the surface of permafrost rose by 3°C (37.4°F) these last 20 years.
Of 83 species kangaroos, 9 disappeared and 28 can be found on the ‘red’ list of endangered animals.
Intense heat waves and heavier, more frequent rains will provoke floods, cyclones and violent hurricanes with increasingly strong winds. Drinkable water resources will decrease and this will compel people who are affected to migrate.
It is the developing nations and the 325 million of the poorest people in the world who are being most greatly affected by climate change. Hurricanes, cyclones, floods, torrential rains, waves of drought and the rise in sea level threaten numerous countries and, therefore, billions of people. Enormous chunks of ice have disappeared from glaciers and regions around the Arctic and the Antarctic. These chunks of ice have melted, increasing the volume of seawater and, therefore, causing a rise in sea levels. This is posing a threat to people living near or on coastlines, as the rise in sea levels is flooding what were once inhabitable coastal areas. This has also disturbed and even destroyed certain ecosystems with species becoming extinct and deserts being extended, and it has also given rise to an increase in infectious diseases that could potentially spread throughout the world.
Global warming is a phenomenon concerning the increase in average temperatures of oceans and the atmosphere throughout the world over several years. One of the consequences of industrialisation has been significant changes seen in climate. The strong concentrations of greenhouse gases generated by industries and other human activities have provoked global warming. The accumulation of greenhouse gases in the atmosphere affects the climate of the earth; it has caused an abnormal warming of our planet. The consequences of global warming have been significant and could become very severe if nothing is done to at least reduce the rate at which temperatures are rising. Some of these consequences are:
- Heat waves;
- Severe storms and floods;
- The disappearance of the ice caps and glaciers, which cause a rise in sea levels;
- The disappearance of 1 million species of flora and fauna over the next 50 years.
The effects of global warming can already be seen; the melting of glaciers, a rise of about ten centimeters in sea level, as well as a reduction in the thickness of Arctic polar icecaps have been seen. The effects of global warming will soon be felt by billions of people as floods, periods of drought, reduced potable water supplies, the proliferation of diseases like malaria, and the disappearance of coastal zones and islands of low elevations become more common. In the longer term, we can envisage the disappearance of most coastal regions in the world as it has been predicted that if icecaps continue to melt at the rate they are presently melting, there will be a rise of 6 meters in sea level. The predictions of increases in temperatures by the end of the century vary between 1.8°C and 4°C. The increases in temperature that have already been observed have not been uniformly distributed over the planet: in the North Pole, the increase in temperatures has been two times higher than increases in temperatures seen in other parts of the world.
Over a third of the world's population was unaware of global warming, with people in developing countries less aware than those in developed, and those in Africa the least aware. This is ironic seeing that those who are most affected are those who are the least aware of global warming and its consequences.
Whenever the term “global warming” is uttered, most people think of fossil fuels. This is because people lay the blame on fossil fuels as they see them as being the cause of global warming. However, this is a problem that has been engendered by human activities. Fossil fuels have existed for millions of years. It did not become a problem until humans began burning them as fuels to create energy. One major solution that could be adopted is to opt for “clean” fuels like wind power and Biofuels. This could possibly be a workable solution until there is not enough room to grow Biofuel sources or until the production of grains as food is not enough to meet demand. Therefore, what I propose is that we pressure governments to support the use of clean fuels such as shale gas, Biofuels, wind and hydropower while encouraging reductions in fossil fuel consumption.
THE KYOTO PROTOCOL
The Kyoto protocol is an international treaty aiming at the reduction of greenhouse gas emissions, within the framework of the Outline agreement of United Nations on climate change. The participating countries have been meeting once a year since 1995. Signed on December 11th, 1997 during the 3rd annual conference in Kyoto, Japan, it came into effect on 16th February, 2005 and in 2010 was ratified by 141 countries.
There are numerous scientific uncertainties in predicting averages in the rise in earth’s temperature and its distribution over different regions. These figures are also disputed amongst scientists. An important debate is taking place at present concerning the actions to be implemented to limit or invert future warming and the measures that could be adopted to face the consequences that are still not well defined themselves. Most governments, with the notable exception of the United States, signed and ratified the Kyoto Protocol, which aims at reducing greenhouse gas emissions to levels that existed in 1990. New technological solutions to the problem of global warming could significantly modify the economy of our societies.
SOS PLANET EARTH :
Ecology is important these days … The air is becoming stifling, water bodies are polluted, droughts are raging and melting ice is causing problems for people living on coastlines because of global warming. Cleaning the earth is not the responsibility of just a few … We must all act if we are to save our planet. Think about our future. Act!!!
Melting of Ice Floes :
Several studies indicate that there has been a reduction in sea ices including in ice floes. Ice floes are very large sheets of ice that float on seawater. There has been a considerable diminution of sea ice that has occurred rapidly since the 1970s, reducing from a surface area of 8.5 million km2 as recorded between 1950 and 1975 to 5.5 millions km2 in 2010.
Observations by satellite show that ice floes in the Arctic Ocean have been losing their surface area. In addition, it has been observed that these large sheets of ice are thinning down, particularly around the North Pole. The average age of ices has reduced over the period between 1988 and 2005 from 6 years to 3 years. Scientists have observed that there is now a higher percentage of younger sea ice than older ice, which indicates that ice sheets are melting more rapidly. The reduction in the average area of Arctic ice floes since 1978 has been in the order of 2.7% (+/- 0.6%) over a decade, while the minimal area of ice floes at the end of summer decreased by 7.4% (+/- 2.4%) over the same decade. The warming or average increase in temperature observed in the Arctic region has been around 2.5 C, which is substantially higher than the average 0.7 C increase seen around the planet. The average thickness of sea ices have reduced by 40% between the periods 1958-1976 and 1993-1997. In 2007, there were fewer ice floes in summer than ever before and, this year, satellite observations have shown that ice floes are melting at an accelerating rate; there was a 20% reduction in ice floes over summer.
There has been a fight against global warming with efforts being made to conserve natural resources and fossil through promoting environmentally friendly energy. New sources of energy that have emerged include aquathermal, geothermal, and solar power energy.
The Greenhouse Effect:
In recent years, there have been significant changes with regard to climatic conditions and the environment. Several scientists from various disciplines were interested in the subject and showed that these changes are related to the gases in our atmosphere. Several gases contribute to global warming. These gases include carbon dioxide (CO2), methane (CH4) and water vapour. Normally, about 28.3% of the radiation from the sun entering earth is immediately reflected back into space by air molecules, white clouds and the light-colored parts on earth. 20.7% of the radiation is absorbed by the atmosphere and 51% by the surface of the earth. This portion that is absorbed by the surface of the earth is the energy that remains in the earth’s atmosphere through both day and night in the form of infrared rays. These infrared rays are either absorbed or reflected back into the earth’s atmosphere by greenhouse gases, and this warms the atmosphere. When the infrared rays are reflected back into the earth’s atmosphere, we have what is called "greenhouse effect" occurring. It is this process that allows the earth to maintain the heat necessary for life on earth given that without this phenomenon, the average temperature of air at the surface of the earth would be only 15 C and there is the potential of the earth's temperature dropping to -18 C. Therefore, the greenhouse effect is necessary for life and survival. However, what is unnecessary is an excess of that portion of infrared rays that are maintained in the earth’s atmosphere. Global warming is caused by this excess because too much energy is being reflected into the earth’s atmosphere by excess greenhouse gases that humans are producing and emitting into the air. Presently, global warming is accelerating and becoming very alarming. The highest temperatures of the millennium were probably those that were recorded in the 90s. The subsequent years following the 90s have been labeled the scorching of the third millennium. By2100, some scientist predict that there will be an average temperature increase of about 1 4 C. However, this is an optimistic prediction because others are forecasting more dire circumstances, predicting that the earth will experience an average rise in temperature of around 5.8 C. According to some scientists, the impacts of global warming are devastating. Thus far, there have been some changes observed that are attributable to global warming. The sea level has risen between 10cm and 20cm over the past century, the thickness of ice in the Arctic has decreased by 40% in a decade and the thickness of snow has also decreased. In addition, the phenomenon El Nino is occurring more often than before, and the timing of reproduction and migration of animals have changed, indicating changes in ecological processes. This could be associated with decreases in freshwater sources or increased fires in forests. Researchers are also predicting that with global warming, a rise in epidemics in developing countries, and increased mortality rates among the frail will be seen. It is also possible that agricultural production will consistently decrease as animals respond negatively to the stress caused by increased heat.
Global warming is the abnormal heating of the earth resulting in rises in average temperatures of oceans and atmosphere over several years.
The climate of an area in the world is defined as a description of averages and meteorological extremes in this given place. The climate is naturally variable as shown through irregularities and variations in seasons from one year to the next. This variability is normal as are the movement of the ocean currents, volcanic eruptions, solar radiation and the other still partially misunderstood climatic phenomena. Furthermore, our climate also has its extremes – devastating occurrences of floods, droughts, severe hail, tornados and hurricanes are not unusual in certain climates. However, for some decades, certain studies have shown indications of unusually frequent occurrences of these phenomena at a global level linked to the warming that is being felt around the world.
Consequences of Global Warming:
Global warming has very worrisome consequences on humans and the environment:
These consequences include the warming of seawater, melting of glaciers and the decrease or even disappearance of sea ice in certain zones around the Arctic and the Antarctic, which are causing a rise in sea level. This has resulted in the flooding of certain coastal zones as the volume of seawater is increasing not only due to the melting of ice but because warm water is more voluminous than cold water. This disturbs and sometimes even destroys ecosystems; some animal and plant species have become extinct and there has been an extension of deserts, both of which have been attributed to global warming. In addition, such rises in temperatures could prompt a faster and less controllable spread of infectious diseases.
More intense heat waves and stronger, more frequent rains could see an increase in the number of floods, cyclones and severe hurricanes with more violent winds. Potable water resources could also decrease, which could have anthropological consequences such as migration.
Developing nations and 325 million of the poorest people in the world are and will be the most affected group faced with climate change. Hurricanes, cyclones, floods, torrential rains, waves of drought, rises in sea level threaten numerous nations and billions of people.
At present, predictions of rises in temperature vary between 1.8°C and 4°C by the end of the century. The increase will not be uniformly distributed throughout the planet as it has not been in the recent past: Around the North Pole, over the last ten years, average temperatures increased twice as quickly as increases seen throughout the rest of the world.
Impact of Global Warming on humans:
Besides the increase in natural disasters, the agricultural returns could decrease and the zones where vectors and diseases such as cholera and malaria are present could widen. This could affect numerous growing populations in tropical zones. In addition, it could compel groups of people to migrate.
Peoples’ lifestyles could also be modified as were that of the Inuits of Kuujjuaq located in north of Canada. Air conditioners were ordered for these people by their mayor, Larry Watt in 2006 after temperatures increased to 31°C.
Some positive consequences:
Although the problem of global warming is viewed largely negatively, there have been some positive consequences for some groups in certain regions throughout the world. These positive consequences lack recognition in the media and remain mostly unpublished. In addition, positive consequences have resulted from the fight against the problem of global warming. Global warming has increased awareness amongst individuals and political groups of the impacts that human activities have on the environment. As a result, there have been developments of innovative technological solutions. Some other positive consequences include:
- A lower mortality rate during winter in temperate zones;
- An increase in agricultural returns in temperate zones;
- An increase in water resources in certain dry areas close to the tropics;
- A decline in energy consumed for heating.
The impact on animals:
Each year, hundreds of species are disappearing due to global warming. Humans have destroyed natural habitats in cutting down vast areas of vegetation for timber, and in clearing land to make way for housing, roads, agriculture and industry. While humans found ways to create comforts for themselves, animals suffered losses of their habitats and means for survival. Some were even killed and stuffed as trophies purely for enjoyment. At our present rate of consumption, we could completely destroy habitats and ecosystems. As negative and pessimistic it may sound, such is the doom that awaits animals.
Greenhouse Gases as the Cause of Global Warming :
Today, almost all scientists agree in imputing the major part of global warming of the last few decades of the 20th century to greenhouse gases produced by human activities. The main culprits have been named as being carbon dioxide, which represents 70% of emissions, and then methane. The concentration of gases in the atmosphere has not stopped increasing since the beginning of the industrial revolution. Since 1750, the concentration of carbon dioxide increased by 31 % and that of methane by 150%. A portion of these gases remain in the atmosphere while the rest is absorbed by oceans and vegetation.
The Melting of Ice Sheets in Antarctica and in Greenland is Accelerating: :
According to a report released by The International Board for Science and The World Meteorological Organization published in 25th February, icecaps of Greenland and Antarctica are melting at a faster rate than previously thought, rapidly increasing the sea level.
The decline in salinity of deep waters with the melting of icecaps near Antarctica could also perturb traffic on oceans.
The melting of ice in Greenland has accelerated to such an extent that for the first time, the movement of ice provoked earthquakes. About a million square kilometers of ice floes have melted this year, clearing large areas in the northwest of ice, and hence creating a passageway free of ice sheets. The forecasts of Horizon 2030 by the Intergovernmental Panel on Climate Change (IPCC) occurred as predicted this summer. It has become evident that we are no longer capable of predicting in a reliable way the scale of the current climate change.
The scientists who observe icecaps have noticed that the movements of gigantic blocks of ice create shock waves that provoke earthquakes of magnitude 3 on the Richter scale.
The melting of ice has accelerated so much that a report by United Nations published this year has been declared outdated by its authors.
The glaciers of Greenland are immense; they are the second largest in the world, and the complete or even partial melting of these glaciers would have catastrophic consequences. Ice sheets around Greenland have thicknesses that reach 3 kilometers, and if these sheets were to melt, there would be a rise in sea level of about 7 meters.
SPECIES MOST ENDANGERED BY GLOBAL WARMING :
Climate change threatens a host of animals other than just polar bears. These other threatened species include:
The Emperor Penguin may face food shortages because of a reduction in ice shelf under which the bird hunts for the shrimp-like krill on which it feeds.
Ringed Seals may be faced with a need to migrate further north in order to find ice on which to raise their young.
The Arctic Fox may face competition for territory from red foxes that are now able to migrate into the tundra because of global warming.
The Beluga Whale is facing increased human intrusion into its habitat due to an increase in boat travel around its habitat facilitated by reductions in ice.
The Koala Bear is suffering from the decreased nutritional content in Eucalyptus leaves on which it feeds. The decreased nutritional content is due to way in which the increased amount of carbon dioxide in the atmosphere affects Eucalyptus trees.
The Leatherback Turtle is suffering from the rising temperatures of the beach sand in which it lays its eggs. This is hindering reproduction of the species.
According to a report, polar species are being affected by the melting of ice resulting from global warming. The ringed seal is being forced further north as the sea ice it relies on for pup-rearing decreases. The Emperor Penguin, highly adapted to harsh Antarctic conditions, faces a similar problem; regional sea ice, which it needs for mating, chick-rearing and moulting, is declining. Reduced ice cover also means less krill, and this affects food availability for the emperor penguin and many other Antarctic species.
The Arctic tundra on which the arctic fox depends is disappearing as new plant species are flourishing with the warming. As the habitat changes from tundra to forest, the red fox, which preys on the arctic fox and competes with it for food, is able to move further north, reducing what was once clearly the territory of the arctic fox. The Arctic's beluga whale is likely to be affected by global warming both directly, through loss of sea ice and the subsequent difficulty in finding prey, and indirectly, through human activity as melting sea ice opens up previously inaccessible areas. Collisions with sea vehicles, pollution from these vehicles and increased gas and oil exploration in these now accessible areas all put this highly sociable mammal at risk.
Global Warming: Between Droughts and Floods
Recently the consequences of climate change and global warming have been front page news all over the world including in Bulgaria. The big floods that inundated both Western Europe and, more severely, Central Europe affected this country for two or three years. In Bulgaria, particularly rigorous winters during which -30°C are reached have been seen and have begun to alternate with winters during which spring temperatures are seen, as was the case this winter. Naturally, nobody complained about it. However, following the relatively warm winter, there was a big drought as predicted by farmers. This was problematic as harvest reduced by 70% due to the lack of germination of wheat and other cereals. Producers of cereals are already getting ready to launch protests all around the country to pressure the government to decree a state of emergency and to ask the European Union for help to compensate for the large losses experienced. The heavy rains in Bulgaria that lasted for a week arrived too late to save their wheat harvest. Moreover, these rains only brought additional losses as flooding and landslides occurred in many places. Tornadoes, a once unknown phenomenon in Bulgaria, were even seen.