GLOBAL WARMING & CLIMATE CHANGE

INTRODUCTION

All over the world, climate change in the recent times has become a common topic. Particularly in Australia, the impacts of climate change are being felt very severely because of "the big dry spell" - a six-year record drought - which has parched the Aussie bread basket. On April 19, 2007, Prime Minister John Howard actually asked the whole country "to pray for rain". Climate change in Australia has become from a non issue to a political/election issue which can tip the boat. The Labour Party led by Kevin Rudd proposes a 60% reduction in Australian CO2 emissions from 2000 levels by 2050. The parties are also promising subsidies to retrofit homes with energy saving systems.

There' is no time to waste. As Al Gore, a tireless champion for action on global warming, says, "This is our only home and that is what is at stake - our ability to live on planet Earth, to have a future as a civilization." Let's not forget what happened to the Indus Valley Civilization.

Diane Walkington, head of species for WWF-UK, said: "The polar bear has been stolen from future generations by nothing less than the selfishness of man".

The earth's climate is dynamic and always changing through a natural cycle. What the world is more worried about is that the changes that are occurring today have been speeded up because of man's activities. These changes are being studied by scientists all over the world who are finding evidence from tree rings, pollen samples, ice cores, and sea sediments.

The most significant international action to address climate change was the Kyoto Protocol which came into effect in 2005. More than 170 countries are its members today including India. The notable exceptions are US and Australia. Every country is adding to the problem. Some are more responsible than others. The big offenders must bear the greater burden of mitigation costs.

Concern about climate change came into prominence after Tsunami of 2004 and the Hurricane Katarina in the US. The academy award winning documentary by Al Gore "An Inconvenient Proof" generated social dialogue in the academic circles. Economics of climate change and the economic impact of climate change was highlighted by Nicholas Stem, a former World Bank and UK Economist in a recent global review.

The thermohaline ocean current – which moderates temperatures worldwide, preventing Europe from having a climate similar to Alaska - is slowing. Glaciers in Greenland, Alaska, the Himalayas and the Antarctic Peninsula are retreating. Sea ice in the Arctic Ocean during summer is disappearing. Permafrost (Permanently frozen soil) in Canada, Alaska and Siberia is melting at an alarming rate. Hurricanes are becoming more numerous and more intense, and sea levels are rising.

GREEN HOUSE GASES

The earth's climate is influenced by the Sun. This energy heats the planet, which in turn radiates that heat back into space. However, much of this heat is retained by various gases in our atmosphere, i.e. carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O); In just right quantities the above gases keep the earth warm for life to exist. Temperatures would be similar to our airless moon, ranging wildly from 225°F during day to negative 2430F at night.

But due to green house gases, the Earth's average temperature is a hospitable 60°F. However, problems arise when the concentration of these gases increase.

Huge amounts of carbon have been captured by plants and burled "in the ground in the form of coal, oil and natural gas, called fossil fuels (i.e. in contrast to human beings, plants take in CO2 and expel Oxygen). These fuels have accumulated over time, perhaps, for millions of years. With the advent of the Industrial Revolution, mankind began extracting and burning earth's vast reservoirs of these fuels. This released millions of tons of carbon in the form of CO2 into atmosphere, thus increasing the levels of green house gases. Atmospheric concentrations of CO2 have increased by nearly 30%, Methane concentrations have more than doubled and Nitrous Oxide concentrations have risen roughly 15%. These increases have enhanced the heat trapping capability of earth's atmosphere, and will continue to do so for years to come.

Fossil fuels burned to run cars and trucks, heat homes and businesses and power factories are responsible for about 98% of CO2 emission, 24% of Methane emissions and 18% of Nitrous Oxide emissions. A1so contributing a significant share of emission are increased agriculture, deforestation, landfills, industrial production and mining activities. In 1997,U.S. discharged roughly 1/ 5th of world's green house gases.

In the absence of emissions control policies, CO2 cocentrations in the year 2100, are projected to be 30 to 150% higher than today's levels. However, even if human beings were to cease emitting heat-trapping gases into the atmosphere, the climate still would not stabilize for quite sometime, as the gases that are already there will remain for decades, even centuries.

Other factors - natural climatic variations, changes in Sun's energy, and the cooling effects of pollutant aerosols - effect our planet's temperature. Understanding of this threat is incomplete.

The Intergovernmental Panel on Climate Change (I.P.C.C.) projects that the planet will be warmer by additional 2.2 to 10°F in the next 100 years. This large range is due to various uncertainties, such as future green house gas emission rates, the possible cooling effects of atmospheric particles such as sulfates, and the climate's response to changes in the atmosphere.

INDIA

The glaciers in the Himalayas cover about 38,000 sq. km. The glacial melt feeds the Indus, the Ganga, the Brahamputra and their tributaries. They have influence over temperature in the plains, the hydroelectric power projects and agriculture. How will the melting glaciers wreak havoc on the rivers and agriculture in particular? Glaciers are receding at unnatural rates. This means our northern rivers, fed by glacier melt will first see floods and then shortages of freshwater flows. We will also see more heat waves; more extreme events - floods - and loss of crop productivity. The sea is bound to rise on our shore lines adversely affecting the cities close by, particularly in the low lying areas such as Mumbai, Panaji, Kochi, Chennai, Vizag, Purl and Kolkata. Our coastal area is 7600 km long where about 20% population lives. The rising see level will submerge coastal areas. Already the Sunderbans has lost 31 km of land mass and if this trend continues, another 15% of the hospitable area will be under sea by 2020, displacing a huge population.

This will influence and increase the frequency of cyclone. The most vulnerable parts in this regard would be the east coast including Andhra Pradesh, Orissa and West Bengal. The most vulnerable cities will be Mumbai and Chennai, according to the UN Panel report.

ASIA

Asian countries will be most adversely hit as 75% of people in Asia are vulnerable, according to an IIED, UK study. A rise in sea level by a metre would displace about 7 million people in India and submerge 5,764 sq.km. of land. The sea is expected to rise by15.38 em by 2050 in India, according to the study.

AFRICA

Rising temperatures in Africa are blamed for increasing the frequency of droughts, floods and storms. The continent's fabled wildlife is struggling to adapt to shifting ecosystems that could lead to mass extinctions.

Africa is the world's poorest continent. It is already paying a high price for global climate change. Experts say global warming may be to blame for the gradual melting of snow atop Tanzania's famed Mt. Killimanjaro. There is evidence that Lake Victoria, Lake Chad and parts of the Nile River are all gradually drying up due to warmer temperatures.

"There has been an observable upward trend in temperatures in parts of Africa, for example in parts of eastern and Central Africa and the (South African) Cape area, as well as emergent water shortages in Western Chad and Darfur regions," said Professor Bob Scholes of South Africa's Centre for Scientific and Industrial Research. "Apart from these factors we have also witnessed an upward spread in bird and fish species, such as the Savannah birds, which have migrated due to warmer temperatures."

South Africa is rated as Africa's largest emitter of harmful green house gases. According to International Energy Agency it released 318 million tonnes of Carbon Dioxide (CO2) in 2003.