Global warming
Pollution has direct effects and indirect ones. Acid rain, described on the acid rain page, is one direct effect: a harmful condition caused by industry releasing oxides of nitrogen and sulphur. Global warming is another.
Global warming
When the atmosphere holds a high concentration of greenhouse gases made of molecules with many atoms — carbon dioxide, methane, chlorofluorocarbons (CFC) — the greenhouse effect is stronger. Much of the Sun's heat reaching the Earth is re-radiated from its surface. But as the concentration of greenhouse gases rises, the amount of heat escaping from the Earth falls, because those gas molecules absorb the heat radiation and re-radiate it. So the temperature of the atmosphere rises and the Earth's surface warms.
Figure to be added
Rising
Air temperature near the surface
Humidity
Ocean and sea-surface temperature
Sea level and ocean heat content
Land temperature
Shrinking
Glaciers
Snow cover
Sea ice
Some harmful effects of global warming:
- As the surface warms, glaciers at the poles melt.
- Rising sea level floods islands.
- The world's climate patterns change.
Why Sri Lanka should care
An island is among the first places to feel a rising sea: low coastal land, lagoons and the wells near the shore take in salt water, and beaches erode. Changing climate patterns mean monsoons that arrive late or fail, longer droughts in the dry zone and heavier floods elsewhere — hard on farmers who plan by the seasons. Warmer seas bleach and kill coral reefs, which protect the coast and feed fish. The causes lie partly far away, but every country adds its share of greenhouse gas.
More greenhouse gas, a warmer Earth
Extra CO2, methane and CFCs trap more heat: glaciers melt, sea level rises and climate patterns change.