Global warming is the name given by scientists for the gradual increase in temperature of the Earth's surface that has worsened since the industrial revolution.

 

Over the past two decades the effect has become more marked. Considerable evidence exists that most of this warming has been caused by human activities... that's to say we have altered the chemical composition of the atmosphere through a build up of greenhouse gases – primarily carbon dioxide, methane, and nitrous oxide.

 

What if we do nothing? Rising global temperatures will cause sea level to rise and alter local climate conditions, affecting forests, crop yields, and water supplies. It may also affect human health, animals, and many types of ecosystems. Deserts may expand and some of our countryside may be permanently altered.

 

What will happen in the future if we do nothing?

 

Climate model simulations predict an increase in average surface air temperature of about 2.5°C by the year 2100 (Kattenberg et al., 1996).

The likelihood of "killer" heat waves during the warm season will increase (Karl et al., 1997).

The IPCC Second Assessment Report estimates that sea-levels will rise by approximately 49 cm over the next 100 years, with a range of uncertainty of 20-86 cm.

Sea-level rise will lead to increased coastal flooding through direct inundation and an increase in the base for storm surges, allowing flooding of larger areas and higher elevations.

Further melting of the Arctic Ice Caps (at the current rate) could be sufficient to turn off the ocean currents that drive the Gulf Stream, which keeps Britain up to 6°C warmer than it would otherwise be.