It refers to the increasing average temperature of Earth ‘s atmosphere and oceans nice the late 1 9th century and its probable continuation. Warming of the climate system is unequivocal and scientists are more than 90% certain that most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and the burning of fossil fuels. Causes of global warming: The causes are mainly from us the human race and the effects on us will be severe. Greenhouse gases: The greenhouse effect is the procedure by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet’s lower atmosphere and reface. The major greenhouse gases are water vapor which causes about 36-70% of the greenhouse effect, carbon dioxide (CA) which causes 9-26%, methane (CHI) which causes 4-9% and ozone (03) which causes 3?7%. Human activity since the industrial revolution has increased the amount of greenhouse gases in the atmosphere leading to increased radioactive forcing from CA, methane, troposphere ozone, Cuffs and nitrous oxide. Solar activity: Solar variations causing changes in solar radiation energy reaching the Earth have been the cause of past global warming. The effect of changes n solar forcing in recent decades is uncertain but small with some studies showing a slight cooling effect while others studies suggest a slight warming effect. An increase in solar activity should warm the stratosphere. Methane: Methane production occurs in oil manufacturing, cattle raising, wet cultivation of rice with methane-producing conditions.
Every year humans release 350 to 550 million tons of methane into the atmosphere. Methane like- carbon dioxide traps the sun’s energy and causes global warming. Fossil fuel : Everyday more electric gadgets flood the market and without disappeared alternative energy sources we are highly dependent on burning coal for our personal and commercial electrical supply. * Burning gasoline for transportation: With our population growing at an alarming rate the demand for more cars and consumer goods means that we are increasing the use of fossil fuels for transportation and manufacturing. Deforestation: The use of forests for fuel (both wood and for charcoal) is one cause of deforestation but in the first world our appetite for wood and paper products, our consumption of livestock grazed on former forest land and the use of replica forest lands for commodities like palm oil plantations contributes to the mass deforestation of our world. Forests remove and store carbon dioxide from the atmosphere and this deforestation releases large amounts of carbon as well as reducing the amount of carbon capture on the planet. * usage of chemical fertilizers on croplands: The use of chemical fertilizers has risen dramatically.
The high rate of application of nitrogen rich fertilizers has effects on the heat storage of cropland and the run-off of excess fertilizers creates ‘dead-zones’ in our oceans. * Population: Another major man made cause of global warming is population. More people mean more food and more methods of transportation. That means more methane because there will be more burning of fossil fuels and more agriculture. * Industrial Revolution: New energy hungry inventions created in the industrial revolution helped spark much of today’s global warming. Hole in ozone layer: It was caused by greenhouse gases and ozone depleting chemicals has increased IV * Invention of the automobile: rays making the surface of the Earth hotter. It is a new era of pollution and gases and has had a serious negative impact n the environment. * Disposable packaging: To keep foods fresher longer and to prevent breakages more disposable packaging Was created which causes deforestation, emissions and the release of gases. * Growth of the oil industry: It came about as the result of man’s need for more oil to fuel cars, machines, trucks, boats, and homes.
The end result is those oil pollutants end up in the air as we become more dependent on oil. Effects of global warming: * Rising sea levels: There are two main factors that have contributed to observed sea level rise. The first is Thermal Expansion- as ocean water warms t expands. The second is from the contribution of land-based ice due to increased melting. Scientists predict an increase in sea levels worldwide due to the melting of two massive ice sheets in Antarctica and Greenland. Effects on weather: As global warming increases the probabilities of certain types of weather events are affected.
Changes have been observed in the amount, intensity, frequency and type of precipitation. Widespread increases in heavy precipitation have occurred even in places where total rain amounts have decreased. Also increased extremes of summer dryness and winter tenets are projected for much of the globe meaning a generally greater risk of droughts and floods. * Ocean pollution: The role of the oceans in global warming is a complex one. The oceans serve as a sink for carbon dioxide taking up much that would then. Sis remain in the atmosphere but increased levels of CA have led to ocean acidification. Furthermore as the temperature of the oceans increases they become less able to absorb excess CA. The ocean has also acted as a sink in absorbing extra heat from the atmosphere. * Food supply: Global warming will impact agriculture and DOD production around the world due to the effects Of elevated CA in the atmosphere, higher temperatures, altered precipitation and transpiration regimes, increased frequency of extreme events and modified weed, pest and pathogen pressure. Health: Human beings are exposed to global warming through changing weather patterns and indirectly through changes in water, air and food quality and changes in ecosystems, agriculture, industry and settlements and the economy. Global warming is responsible for various kinds of diseases like- cancer, heart diseases, influenza, tuberculosis, viral ever, cholera, diarrhea, malaria, dengue fever etc. * Floods and weather disasters: Global warming increases the rate of flood ; and tropical cyclones.
The severity of storms such as hurricanes and cyclones is * Drought: The effects of drought on health include deaths, increasing. Malnutrition, infectious diseases and respiratory diseases. * Heat waves: Hot days, hot nights and heat waves have become more frequent. Heat waves are associated with marked short-term increases in mortality. Heat-related morbidity and mortality is projected to increase. K Fires: In some regions hanged in temperature and precipitation are projected to increase the frequency and severity of fire events. Forest and bush fires cause burns, damage from smoke inhalation and other injuries. Widespread extinction Of species: Global warming now represents at least as great a threat to the number of species surviving on Earth as habitat-destruction and modification. Rising temperatures could lead to the extinction of more than a million species. * Economic consequences: Most of the effects of anthropogenic global warming won’t be good. And these effects spell one thing for the countries of the world economic consequences. Hurricanes cause billions of dollars in damage, diseases cost money to treat and control and conflicts exacerbate all of these.
Global warming and future of Bangladesh: * Bangladesh with 140 million population and low lying coastal geography is one of the most vulnerable nations in the world which is at maximum risk of climate change which is one of the unconventional effects of global warming on Bangladesh. * The unconventional effects of global warming on Bangladesh can be easily felt. Be it a small village on the rugged coastline or densely populated city like Dacha global warming has affected lives of all. Few years ago water tasted very sweet but now the flavor is salty.
This the sign of the brackish water from the Bay of Bengal is encroaching and surging up fresh river water of Bangladesh as well as percolating deep inside the soil and underground water supply on which people depend for daily supply of their drinking water. * The salt making its way to the payday fields belonging to villagers is destroying their only source of income. * Bangladesh comprises 230 rivers which swells during the rainy season combined with river water from the melting glaciers from the Himalaya in north and an encroaching Bay of Bengal in south which makes the region prone to severe flooding. Global warming affected food output of Bangladesh and in turn the lives Of poor farmers. The rising soil salinity has affected the quality of food production. To boost the declining income farmers are now turning towards home based shrimp farming. Shrimp farming is in turn hampering the balance of the ecosystem which is adding to the unconventional effects of global warming on Bangladesh. * Global warming has adversely affected the lives of the flora and fauna of the gigantic Sandbars thus affecting couturiers to a large extend. Declining mangroves in the Sandbars are mainly affecting lives of tigers.