What is Global Warming?How did we get into this mess?

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The year 2003 was the second warmest on record, jointly with 2002 when values are rounded to two decimal places.

In descending order, the warmest years have been: 1998, 2002 & 2003 (joint), 2001, 1997, 1995, 1990 & 1999 (joint), 1991 & 2000 (joint).

Figures compiled by the UK Meteorological Office and the Climatic Research Unit of the University of East Anglia for the World Meteorological Organisation, show that the ten warmest years globally since 1856 have now occurred in the 1990s and 2000s.

Global warming does not happen by default. It is humans who create the problem. Every bit of coal, every litre of oil or gas that humans burn adds to the load of gases in the atmosphere that wrap around the planet like an ever thicker blanket, trapping heat, smothering people and nature.

                               
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Source: data compiled jointly by the Climatic Research Unit and the UK Meteorological Office Hadley Centre for the World Meteorological Organization


CO2: the main global warming gas
Carbon dioxide (CO2) accounts for over 80% of global warming pollution. Atmospheric levels of CO2 are now higher than at any time in the past 420,000 years.
CO2 mainly from coal, oil and gas
Around 97% of the CO2 emitted by western industrialised countries comes from burning coal, oil and gas for energy. Approximately 23,000,000,000 tonnes of CO2 are spewed into the earth's atmosphere every year. That's more than 700 tonnes every second! The global temperature build-up is seriously disrupting the natural balance of the world's climate.

Impacts from the equator to the poles
The impacts of global warming are evident from the equator to the poles. Coral reefs bleached by increasing sea temperatures...alpine forests struggling to move to higher, cooler locations...polar bears under pressure as polar ice shrinks...glaciers melting on overy continent...and economic damage that the insurance industry puts at hundreds of billions of dollars each year. It's 10 years since scientists alerted the world to the dangers of climate change. We cannot afford to let this continue.

Immediate reductions needed to stabilise concentrations
According to the UN Intergovernmental Panel on Climate Change, it would take an immediate reduction in CO2 emissions of at least 60% to stabilise concentrations in the atmosphere at their present level. Making this kind of immediate reduction is impossible but it indicates the kind of pollution cut that's needed to put the brakes on global warming.
Unless effective climate protection policies are introduced, carbon emissions could increase dramatically in the near future and put us on a pathway that would be very difficult to turn around.

We need to stay below 2°C
For this reason, WWF believes that temperature rise should stay well below 2° Celcius in order to avoid dangerous climate change. It has already been shown that 2°C would already bring with it a set of impacts to coral reefs, arctic systems and local communities. We must therefore not go above this.

What does 2°C mean?
It means that we must start reducing emissions now and stay on a low emissions pathway to avoid loading the atmosphere with too much CO2. In scientific terms this means staying well below a concentration level of 450 ppmv (parts per million by volume) in the atmosphere. In emissions terms, this means cutting emissions rapidly and deeply far below current levels.

from WWF