Global warming threatens the survival of man and other organisms on earth
Posted: Dec 2006 (Return to the original web page from this print version)
 |
| Rapid meling of ice sheets and galciers will lead to short term floodings, and droughts in the long run. |
 |
 |
| Melting of ice sheets destroys the habitats of polar bears, sea otters, seals, penguins etc. |
|
|
| With heavy usage of fossil fuels, a large volume of heat trapping gases is being released into the atmosphere. These green house gases include carbon dioxide, nitrous oxide and methane etc. A British study said 2006 would be the sixth-warmest year worldwide since records began. |
|
| The major consequences of global warming include: |
|
 |
Melting of ice sheets and glaciers |
 |
|
Rise in sea levels and flooding of low-lying areas |
|
|
More extreme climates such as storms, flooding, droughts, and heat waves etc. |
|
|
Drying up of rivers and lakes, and extensive desertification |
|
|
Warmer water will lead to massive death of coral reefs and fish stock |
|
|
A lot of animal and plant species may go extinct |
|
|
Proliferation of infectious diseases |
|
|
The changes in climate and water supplies will result in extensive crop failure, famines, and political conflicts in the fight for resources such as water and food. |
|
| |
| How you can help to reduce green house gases |
|
|
Reduce consumption of unnecessary or non-essential items. This would reduce factory emissions in manufacturing. |
|
|
Conserve electricity – use only when necessary. This would reduce emissions from power plants. |
|
|
Avoid unnecessary trips by car or by plane. This would reduce emissions from vehicles. |
|
|
| |
|
|
 |
| The water mass in the Antartic ice sheet equals to 70 metres of water in the oceans |
|
 |
| The ice sheet in Greenland is losing around 100 gigatons of ice each year. |
|
 |
| Melting ice in the Artic near Canada |
|
 |
| The Himalayan glaciers are retreating at an alarming rate of 33 - 49 feet per year. |
|
|
| 1. Melting of Ice Sheets and Glaciers |
|
| |
Some scientists predicted that global warming could drive the average global temperature up by 1.4 - 5.8 °C (2.5 - 10.5 °F) over the next 100 years, which would cause glaciers to retreat, oceans to rise and swamp low-lying areas around the world. |
|
| |
Some theories suggest there may be a domino effect in the melting of ice sheets and glaciers. The carbon dioxide and other green house gases released from the melted ice may speed up the melting exponentially. |
|
| |
1.1 The Antartic Ice Sheet |
|
| |
The Antarctic ice sheet is the largest single mass of ice on Earth. It covers an area of almost 14 million square km and contains 30 million cubic km of ice. It holds around 90 percent of the fresh water on the Earth's surface, an amount equivalent to 70 m of water in the oceans. The overall rate of melting of the Antarctic ice sheet will critically determine the rise in sea levels in the next few decades. |
|
| |
Around 75% of the 400 mountain glaciers on the Antarctic peninsula, which protrude from the continent to the north, were known to be retreating. Recent studies showed that glaciers within the much larger western Antarctic ice sheet are also starting to disappear. For e.g., the Rutford Ice Stream (with size larger than Netherlands) slips about a meter (3 ft) a day toward the sea. (More info) |
| |
| |
1.2 The Artic Ice Sheet |
|
| |
The rapid shrinking of the Greenland ice sheet in the Artic is considered an early indicator of the consequences of global warming. In October, 2006, the NASA scientists reported that Greenland is losing 20 percent more ice mass than it gets in new snowfall each year. The net loss in ice mass in Greenland was around 100 gigatons annually between 2003 and 2005. (More info) |
|
| |
In August, 2005, a giant ice shelf broke away from Canada's Arctic at about 497 miles south of the North Pole. It was the Ayles Ice Shelf with roughly 41 square miles in area, equivalent to the size of 11,000 football fields. It became a newly formed ice island in just an hour, leaving a trail of icy boulders floating in its wake. The scientists were surprised because they originally thought the ice sheets would melt gradually instead of dismantling within such a short time span. |
| |
| |
1.3 The Himalayan Glaciers in Asia |
|
| |
Over 67% of glaciers in the Himalayas are melting rapidly, at a rate reaching 33-49 feet a year. This is threatening the livelihood of more than 1 billion people who rely on its river system for water (including China, India, Pakistan, Nepal etc.). The Himalayan glaciers feed into seven of Asia's biggest rivers: the Yangtze, Yellow, Ganges, Indus, Brahmaputra, Mekong, and Thanlwin (formerly known as the Salween). |
|
| |
Flooding will occur in the short term. Over the long term, the Himalayan glaciers will melt entirely and the rivers will run dry for months, and become fed only by annual monsoon rains during summer. A lot of animal and plant species may die. (Related News – Nov 20, 2005) (More info on melting glaciers) |
|
| |
|
| |
 |
| Rising sea levels may flood densely populated cities at low-lying areas around the world . |
|
|
|
| 2. Rise in Sea Levels - Flooding of Low-Lying Areas |
|
| |
Climate scientists who advise the United Nations project that sea levels will rise by 9 cm to 88 cm by 2100 because of global warming. Other researchers suggested that the sea levels could rise by 50-140 cms by 2100. (More info) |
|
| |
Low-lying coasts are prone to flooding from the rise in sea levels. A rise of one meter might swamp low-lying Pacific islands such as Tuvalu, flood large areas of Bangladesh or Florida and threaten cities such as New York, London, San Francisco and Buenos Aires etc. |
|
| |
In addition, the rise in sea levels will destroy the coastal breeding grounds or habitats of a large number of animals and plants. For example, the sea turtles and birds that lay their eggs along the beaches, which may become flooded with sea level rise. The current sites of mangrove forests may disappear. |
|
| |
|
 |
| Johor of Malaysia was flooded in mid Dec 2006 with the heaviest rainfall in 100 years. |
|
 |
| Landslides and flooding in Aceh Province of Indonesia after heavy rain in Dec 2006. |
|
 |
| Warmer ocean water is fueling more severe hurricanes and typhoons. |
|
 |
| As the warm air in the eye of typhoon rises and condenses to rain, energy is released |
|
 |
| Severe drought in South Australia in Dec 2006 results in large areas of ruined farmland. The survival of a lot of animals and plants is being threatened. |
|
 |
| Forest fires destroy the habitats of plants and animals, & damage residential homes |
| |
|
|
| 3. More Extreme Climates |
|
| |
With global warming, scientists predict that extreme events such as heat waves, heavy rain or snowfall, severe hurricanes or typhoons, and droughts may occur with higher frequency. The number of days when the temperature drops below freezing will plummet worldwide. These changes have big impacts, not only on humans, but also on mammals, other animals and plants in the ecosystems. |
|
| |
Some studies pointed out that the Western United States, the Mediterranean region, Brazil, Australia, and the region in the tropical Pacific Ocean are locations more likely to suffer from these extreme climates. |
| |
| |
3.1 Heat waves will worsen in intensity, length and frequency |
|
| |
One of the scary climatic changes involves heat waves and warm nights. The intensity, length and occurrence of heat waves would worsen with global warming. Every part of the globe is predicted to experience a tremendous increase in the number of nights with extremely high temperature. Chicago's 1995 heat wave demonstrated that after three straight hot nights, people start dying. |
|
| |
For example, The North American heat wave that spread throughout most of the United States and Canada in July and August of 2006 killed at least 225 people. The heat wave in Europe in the summer of 2003 killed a few dozen people in Portugal, Spain and France. |
| |
| |
3.2 Heavier Rains or Snowfall |
|
| |
Warmer temperatures increase the energy of the climatic system and lead to more intense rainfall or snow storm at some times and in some areas. |
|
| |
For example, in November and December of 2006, torrential rains and floods have hit up to 1.8 million people in the Horn of Africa, driving tens of thousands from their homes and threatening to trigger epidemics. The countries affected include Kenya, Somalia, Ethiopia, Sudan and Eritrea. Many people are sleeping outdoors in unsanitary conditions, without clean water or food. Diarrhoeal diseases, malaria, and acute respiratory infections have risen two to three-fold, and cholera has been reported in the region. (Related News – Dec 8, 2006) |
|
| |
In mid December 2006, Malaysia experienced the heaviest rainfall in a century and the worst floods in 37 years. Nearly 100,000 people have been made homeless, many of whom desperate for food and water. (Related News – Dec 23, 2006) |
|
| |
Heavy rain and flooding in neighboring Indonesia in December 2006 killed around 100 people and drove more than 200,000 from their homes. Extensive deforestation in the past has significantly increased the risks of landslides and flooding. (Related News – Dec 27, 2006) |
| |
| |
3.3 More Severe Hurricanes or Typhoons |
|
| |
The surfaces of most tropical oceans have warmed by 0.25-0.5 degree Celsius during the past several decades. Warmer water in the oceans pumps more energy into tropical storms, making them more intense and potentially more destructive. If the projected rise in sea level due to global warming occurs, then the vulnerability to tropical cyclone storm surge flooding would increase. |
|
| |
In a tropical cyclone, air rotates inward to the center (or eye), then rises to higher altitudes. As warm, moist air rises, the air cools and condenses to rain, releasing heat. This cycle of evaporation and condensation powers the storm. |
| |
| |
3.4 Droughts and Wildfires |
|
| |
Warmer temperatures increase evaporation of water from the land, lakes and rivers. The water loss may not be compensated by rainfall. Hence there is a higher chance of drought, particularly during summer and fall. Rivers and lakes, especially those in higher altitude, may become dried up. Drier weather also increases the risk of wildfires, which may be triggered by lightening or intense sun heat. |
|
| |
Lake Victoria, with an area of 27,000 square miles, is the greatest of Africa's Great Lakes — the biggest freshwater body after Lake Superior in North America. Its water level has been dropping fast, at least six feet in the past 3 years. Rising temperatures may evaporate up to half the lake's normal inflow from rainfall and rivers. |
|
| |
This would have severe consequences on the ecosystems of the lake, and on the water supply for the region. A further dramatic drop in Victoria's water levels might also threaten the water source for more than 100 million people living along River Nile, which begins its 4,100-mile northward journey at Jinja of Lake Victoria. (Related News – Dec 9, 2006) |
|
| |
|
 |
| Dry lands are being turned into deserts at a faster rate with global warming. Almost a million acres of land becomes desert in China each year. |
|
 |
| China has around 350 million cattle, sheep, goats and yaks. Overgrazing, over-cultivation and deforestation contribute to rapid deforestation in China. |
|
|
| 4. Extensive Desertification |
|
| |
Global warming may turn a large area of dry lands into deserts or semi-deserts. Existing dry lands cover over 40% of the total land area of the world, most significantly in Africa, Asia and Australia. These areas experience low rainfall, which is usually in the form of short, erratic, high-intensity storms. |
|
| |
With higher global temperature, more water becomes evaporated from the dry land. Changes in climate with more extreme weather will result in more droughts and flooding in the dry lands, fueling their degradation into deserts. Over-cultivation, overgrazing, deforestation and poor irrigation practices speed up the process of desertification. This is reflected by an increased frequency of sand storms and dust storms. |
|
| |
Problems of Desertification in China |
|
| |
By the end of 2004, the area of deserts in China totaled 2.64 million square kilometers (1.05 million square miles), or 27.5 percent of total land area. Almost a million acres of land is turned into desert in China every year. |
|
| |
The Badain Jaran Desert and Tengger Desert in north-central China are expanding and merging to form a single desert overlapping Inner Mongolia and Gansu provinces. To the west in Xinjiang Province, two even larger deserts, the Taklimakan and Kumtag, are also heading for a merger. The Gobi Desert is located in Inner Mongolia and Mongolia. Its yellow sands are increasingly theatening the capital in Beijing. (More Chinese info on the deserts in China) |
|
| |
Northwestern China is on the verge of a massive ecological disaster. Millions of rural Chinese in Gansu, Inner Mongolia, and Ningxia provinces may be uprooted and forced to migrate eastward as the drifting sand covers their land. The annual dust storms in spring blowing across northern Asia are choking major cities in China, Korea and Japan. Such sandstorms cause respiratory problems, as well as skin and eye disorders for a large population. (Related News – September 18, 2006) |
|
| |
|
 |
| Coral reefs are very sensitive to changes in water temperature. In higher than normal temperature, they turn white and may die if the situation persists. |
|
| |
|
|
| 5. Massive Death of Coral Reefs and Fish Stock |
|
| |
In October 2006, Researchers warned that more than half of the world's coral reefs could die in less than 25 years, due to rising sea temperatures from global warming, blooming algae and their toxins, silt runoff from construction sites, paints from boats, and other industrial and chemical pollutants. With rise in sea levels, some coral reefs may be starved of energy from the sun. (Related News – Oct 24, 2006) |
|
| |
The coral reefs are hosts for countless marine plants and animals. They can only live in waters between 18°C and 30°C. They are more susceptible to disease and premature death if the sea temperature is higher than normal. In high water temperatures, the coral polyps will lose the symbiotic algae inside them, causing them to turn white, or "bleach", and eventually die. |
|
| |
Up to 30 percent of the world's coral reefs have died in the last 50 years, and another 30 percent are severely damaged. (more info on Coral Reef Bleaching) |
|
| |
As coral reefs are breeding grounds for many fish and marine animals, the bleaching and death of coral reefs will lead to reduction in fish, and probably a disaster in the ecological balance of the marine world. |
|
| |
|
 |
| The more extreme climates of gloabl warming will threaten the survival of a lot of animals and plants. The species that cannot adapt fast enough may go extinct. |
|
 |
| A high percentage of reptile animals are threatened by extinction. |
| |
|
|
| 6. Extinction of Animal and Plant Species |
|
| |
The increase in global temperatures is expected to disrupt ecosystems and result in loss of species diversity, as species that cannot adapt fast enough will die off. The habitats of polar bears, seals, penguin and other ice-dependent animals are disappearing rapidly with the melting of Arctic sea ice, threatening their long-term survival. |
|
| |
The number of Rockhopper penguins has dropped 30% in their South Atlantic habitat of Falkland Island in the past 5 years, reflecting a massive shift in the ecology of the southern Ocean, perhaps linked to climate change. (Related News – Dec 21, 2006) |
|
| |
Global warming has already changed the migration routes and patterns of some birds, fish, turtles and other animals. During winter, some of them are staying farther north rather than migrating to the south as previously. |
|
| |
Even subtle changes in sea temperature can have dramatic impacts on wildlife with rapid depletion of the tiny plankton organisms which form the base of the food web in the oceans. This may contribute to a recent drastic decline in number of some Scottish seabirds, as the fish on which they depend were suddenly deprived of food. (Related News – Oct 5, 2005) |
|
| |
An assessment of the extinction risk from global warming found that more than one million species could become extinct by 2050. (Source) |
|
| |
In November 2005, the World Conservation Union reported that it found 12 percent of all bird species were threatened with extinction, along with nearly one-fourth of the world's mammals, a third of amphibians and 42 percent of all turtles and tortoises. |
|
| |
|
 |
| Warmer weather will foster the growth of bacteria, virus, mould, fungi and parasites. |
|
|
| 7. Proliferation of Infectious Diseases |
|
| |
Warmer weather will foster the growth of bacteria, virus, and fungi. It also favours rapid multiplication of other disease carriers such as rodents, mosquitoes, flies and various insects. There will be an increase in diseases such as malaria, dengue fever, yellow fever, and some forms of viral encephalitis. |
|
| |
Some tropical diseases may spread to locations at both higher altitudes and latitudes, where mosquitoes and parasites can now survive in warmer climates. Extreme weather events such as heavy rainfall or droughts often trigger disease outbreaks, especially in poorer regions where medical treatments and prevention measures may be inadequate. (Related News – Jun 20, 2002) |
| |
|
| |
| Other Feature Articles |
|
|
|
