Don't you feel that the climatic pattern of our environment is increasingly unpredictable?  Changes are so extreme and dramatic!!!!

What is happening in our environment?  The principal change to date is in the earth's atmosphere.  We, the human beings, have changed, and are continuing to change, the balance of gases that form the atmosphere. This is especially true of such key "greenhouse gases" as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O).  These naturally occurring gases make up less than one tenth of one per cent of the total atmosphere, which consists mostly of oxygen (21 per cent) and nitrogen (78 per cent). But greenhouse gases are vital because they act like a blanket around the earth. Without this natural blanket the earth's surface would be some 30^oC colder than it is today.  

The problem is that human activity is making the blanket "thicker".  For example, about three-quarters of the anthropogenic emissions of CO₂ to the atmosphere during the past 20 years is due to fossil fuel burning.  The rest is predominantly due to land-use changes, especially deforestation.  When we destroy forests, the carbon stored in the trees escapes to the atmosphere.  Other basic activities, such as raising cattle and planting rice, emit methane, nitrous oxide, and other greenhouse gases.  If emissions continue to grow at current rates, it is almost certain that atmospheric levels of carbon dioxide will double from pre-industrial levels during the 21st century.  If no steps are taken to slow greenhouse gas emissions, it is quite possible that levels will triple by the year 2100.  

The most direct result is likely to be a "global warming" of 1.4 to 4.8^oC over the period 1990 to 2100, according to the latest projection by the IPCC Third Assessment Report.  The robust scientific evidence shows that the global average surface temperature has increased over the 20th century by about 0.6^oC +/- 0.2^oC.  A recent scientific study, conducted at the Imperial College of Science , Technology and Medicine (London), compares the observational data obtained from satellites that orbited the Earth in 1970 and in 1997.  The comparison shows that less radiation was moving from the Earth into the space in 1997 than in 1990.  This implies that the greenhouse gases are being retained in the Earth's atmosphere, forming a greenhouse-like layer that traps the heat of the Sun close to the planet.  This study is reported in the journal of "Nature" (March issue).

    Illustrations of the Greenhouse Effect 

Source: The Third Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2001)

How the extreme climatic changes affect us?  Personally, we may feel uncomfortable under the hot and humid climate.  In macro-scale, climate change could be a threat to both the human and natural systems.

"Warming oceans are attributed to greenhouse gases", concluded in the studies by the National Oceanographic Data Centre at the National Oceanic and Atmospheric Administration (NOAA). The reports link a warming trend in the upper 3,000 metres of the world's oceans to global warming caused by human activities. It is found that the Atlantic, Pacific and Indian oceans have collectively warmed an average of 0.06^oC since 1955.

Many marine ecosystems are sensitive to climate change. Climatic trends and variability as reflected in multi-year climate-ocean regimes have been recognised to strongly affect fish abundance and population dynamics, with significant impacts on fish-dependent human societies. For example, climate change leads to poleward movement of the boundaries of freshwater fish distributions along loss of habitat for cold- and cool-water fishes and gain in habitat for warm-water fishes, and hence distorts the balance of ecosystems.

Climate change causes threats to the human societies in coastal areas from increased flood, accelerated erosion, loss of wetlands and mangroves, and seawater intrusion into freshwater sources. The extent and severity of storm impacts, including storm-surge flood and shore erosion, will increase as a result of climate change including sea-level rise.

Global Treaty - Kyoto Protocol

From December 1 through 11, 1997, more than 160 nations met in Kyoto, Japan, to negotiate binding limitations on greenhouse gases for the developed nations, pursuant to the objectives of the Framework Convention on Climate Change of 1992. The outcome of the meeting was the Kyoto Protocol, in which the developed nations agreed to limit their greenhouse gas emissions, relative to the levels emitted in 1990: a 8% cut for the European Union (EU), 7% for the USA, and 6% for Japan and Canada.

The protocol still has some way to go before it reaches the status of a binding agreement. It opened for signature in March 1998 and will remain open for one year. Only after that, i.e. from March 1999, will it be open for ratification, acceptance, approval, or accession by Parties to the Convention. To enter into force, it must be ratified by at least 55 countries, accounting for at least 55 percent of the total 1990 carbon dioxide emissions of developed countries.

Three highlights to mitigate the extent of global warming according to the Protocol:

(1) Energy-efficient technology development;

(2) Renewable energy development;

(3) Technology transfer to less-developed countries

In the moment, our world is still highly relying on fossil fuel for electricity generation (almost 2/3).  Coal-burning is most common, accounting for over 52 % in the US; 56 % in Germany; and 43 % in the UK, because of the relative low cost of fossil-fired generation.  However, coal-fired power plants emit more toxic pollutants than any other forms of energy production.  For every megawatt hour of electricity produced, coal generates 2,7071 pounds of CO₂, 13.8 pounds of SOx, 4.8 pounds of NOx, and 3.2 pounds of particular matter.  In comparison, natural gas emits 1,205 pounds of CO₂, 0.008 pounds of SOx, 4.3 pounds of NOx, and negligible particular matter.

Under the fact of increasing world population and economic developments, mounting demand for electricity can be projected.  According to the World Energy Outlook, conducted by the International Energy Agency, world energy consumption increase by 46 to 67 percent by 2010.  In order to meet the mounting energy demand, improvement of energy-efficiency is necessary.  Moreover, for a sustainable future, we can't only rely on fossil fuels, which are non-renewable, development of renewable and alternative energy (e.g. natural gas, wind energy, solar energy) is crucial.

In March 2001, new US President George W. Bush, who believes global warming is a fad, has gone against the scientists and leaders of the world by announcing that the US will not seek to rectify the Kyoto Protocol.  He refused to be part of the Protocol, as it will hurt the US economy.  This is definitely not a good news to the Protocol development, as it needs the ratification by at least 55 countries, accounting for at least 55 percent of the total 1990 carbon dioxide emissions of developed countries in order to enter to force.  Though the US has less than 5 % of the world's population, it accounts for over 25 % of the world greenhouse gases emissions.  For more details of the Bush administration's views on Kyoto Protocol and Global Warming issues, you can see the April issue of "TIME", entitled "A Climate of Despair".

So, what can we do to reduce global warming?

(1) Save Electricity
Whenever we use electricity, we help put greenhouse gases into the air.  By turning off lights, the television, and the computer when you are through with them, you can help a lot.

(2) Bike, Bus, and Walk
We can save energy by sometimes taking the bus, riding a bike, or walking.

(3) Plant Trees
Planting trees is fun and a great way to reduce greenhouse gases.  Trees absorb carbon dioxide, a greenhouse gas, from the air.

(4) Recycle
Recycle cans, bottles, plastic bags, and newspapers.  When we recycle, we send less trash to the landfill, and we help save natural resources, like trees, oil, and elements such as aluminum.

(5) When You Buy, Buy Cool Stuff
There are lots of ways we can improve the environment.  One of the ways to reduce the amount of greenhouse gases that we put into the air is to buy products that don't use as much energy. By conserving energy, we help reduce global warming and make the Earth a better place.  Some products – like certain cars and stereos – are made specially to save energy.

(6) Some Things to Think About
Do you know that you can help the environment if you buy recyclable products instead of non-recyclable ones? Look for the recycle mark – three arrows that make a circle – on the package.  Recyclable products are usually made out of things that already have been used. It usually takes less energy to make recycled products than to make new ones.  The less energy we use, the better.

(7) Solar Energy
Sun produces solar energy.  Solar energy is a fancy way of saying "energy that comes from the sun.  It can be used to heat homes, buildings, water, and to make electricity.  Today, more than 200,000 houses in the United States take advantage of the sun's energy.

(8) Cars
Cars are an important part of life for most people.  But cars also cause pollution and release a lot of greenhouse gases into the air.  Fortunately, there are some cars that are better for the environment. These cars can travel longer on a smaller amount of gasoline.  They don't pollute as much, either.  Using these kinds of cars can help reduce the amount of greenhouse gases in the air.  For example, London will soon be using hydrogen powered fuel cell buses.  A fuel cell combines hydrogen with oxygen to produce electricity, heat and water.  The fuel cell uses this electricity to power vehicle.  The only emission will be water vapor, and thereby is significantly cleaner, in terms of greenhouse gas emission, than the existing petrol and diesel vehicles.

World Water Day (22/3), it is predicted that two out of three people in the world will face water shortage by 2050.  Unless global warming is tackled, the scientists predict that decrease in water supply will be realized, with drought intensifying and rivers and lakes drying up as a result.