GLOBAL WARMING

CLIMATE CHANGE CHARACTERIZED BY A GENERAL INCREASE IN AVERAGE TEMPERATURES OF THE EARTH, WHICH MODIFIES THE WEATHER BALANCES AND ECOSYSTEMS FOR A LONG TIME. IT IS DIRECTLY LINKED TO THE INCREASE OF GREENHOUSE GASES IN OUR ATMOSPHERE, WORSENING THE

GREENHOUSE EFFECT.

RESULTS OF GLOBAL WARMING

■Rising Surface Temperatures: The surface temperature of Earth has increased 0.45 - 0.6 degrees Celsius

■Rising Sea Levels: The average sea level has risen globally by 10 - 25 cm over the past century.

PRIMARY SOURCES

■Increasing of carbon dioxide (CO2) in the atmosphere (30%)

■Diminished Atmosphere: The reflectivity of our upper atmosphere has diminished due to the depletion of certain gases.

■Retained Heat: The amount of heat retained by the greenhouse gases in our atmosphere.

AND EMITS RADIANT ENERGY WITHIN THE THERMAL INFRARED RANGE. THE PRIMARY GREENHOUSE GASES IN EARTH'S ATMOSPHERE ARE WATER VAPOR, CARBON DIOXIDE, METHANE, NITROUS OXIDE AND OZONE. WITHOUT GREENHOUSE GASES, THE AVERAGE TEMPERATURE OF EARTH'S SURFACE WOULD BE ABOUT −18 °C, RATHER THAN THE PRESENT AVERAGE OF 15 °C (59 °F).

THE ATMOSPHERES OF VENUS, MARS AND TITAN ALSO CONTAIN GREENHOUSE GASES.

GLOBAL WARMING CAUSES

FOSSIL FUELS

■The massive use of fossil fuels is obviously the first source of global warming, as burning coal, oil and gas produces carbon dioxide - the most important greenhouse gas in the atmosphere - as well as nitrous oxide.

DEFORESTATION

■The exploitation of forests has a major role in climate change. Trees help regulate the climate by absorbing CO2 from the atmosphere. When they are cut down, this positive effect is lost and the carbon stored in the trees is released into the atmosphere.

INTENSIVE FARMING

■Another cause of global warming is intensive farming, not only with the ever-increasing livestock, but also with plant protection products and fertilizers. In fact, cattle and sheep produce large amounts of methane when digesting their food, while fertilizers produce nitrous oxide emissions.