OTHER ENVIRONMENTAL

ISSUESGLOBAL WARMING

CLIMATE CHANGEEL NINOLA NINA

GLOBAL WARMINGa gradual increase in the

overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.

CAUSES OF GLOBAL WARMING

GREENHOUSE GASESCARBON DIOXIDE (CO2)

METHANE (CH 4)NITROUS OXIDE (N20)

CARBON DIOXIDEIt accounts for 50% of the green house

effect, has increased by 25% .Carbon is emitted mainly by cars,

factories and wherever fossil fuel is used

Deforestation, which is a current global environmental problem, removes trees that would otherwise absorb the carbon dioxide, thus increasing its release into the atmosphere.

METHANE

Responsible for 15%-20% of the green house effect, has more than doubled in the last two centuries due to the burning of wood, increasing areas of rice cultivation, garbage, landfills, livestock, manure, termite mounds, leakage from natural gas exploration and coal mining.

CHLOROFLUOROCARBONS

(CFC’s) account for 15%-25% opf the green house gases and are released from refrigerators, air conditioning units, aerosol sprays, solvents in electronic products, manufacture of foam insulation material, electrical circuit board cleaners, and styrofoam packaging (Buchholz 1998).

A more powerful catalyst than carbon dioxide, a single (CFC) molecule traps 15,000 times more heat than a CO2 molecule.

Although carbon dioxide is more plentiful, it only stays in the atmosphere for decades while a chlorine molecule remains from 75 to 100 years.

NITROUS OXIDE

The laughing gas formed from the breakdown of chemical fertilizers and burning of coal, and industrial processes, accounts for 5% .

OTHER GREENHOUSE COMPOUNDS

Are carbon monoxide, ozone, the synthetic compound halon, water vapor and airborne particles that could radiate sunlight.

GREENHOUSE PROCESS

EFFECTS OF GLOBAL WARMING are the environmental and social changes

caused (directly or indirectly) by human emissions of greenhouse gases. There is a scientific consensus that climate change is occurring, and that human activities are the primary driver.Many impacts of climate change have already been observed, including glacier retreat,changes in the timing of seasonal events (e.g., earlier flowering of plants),and changes in agricultural productivity.

1. Increased probability and intensity of droughts and heat waves

As the atmosphere gets saturated with higher levels of green house gases, surface temperatures on the Earth are bound to increase. These gases tend to absorb and retain more of sunâs heat ��without allowing it to escape freely into the outer space, causing the land, air and water to heat up. This in turn speeds up evaporation of water from the land and fresh water sources, leading to frequent and severe drought conditions. High land and air temperatures create intense heat conditions.

2. Polar ice caps melting

Ice caps and glaciers that dominate the Arctic Pole have started to melt at an alarming rate, submerging vast expanse of land in the process. The melt down is also simultaneously opening up access to vast deep sea oil and gas deposits, including methane in the Tundra region, endangering the Arctic marine ecosystem, impacting shipping routes, and the cool water currents that flow down to Europe and Africa. A tremendous change is also observed in terms of the new land revealed by melting ice, and variations in shore-lines, leading to conflicting international interests in the geographical terrain.

3. More floods

• Heat wave conditions and increasing land and air temperature trigger faster evaporation of water, eventually leading to cloud formation and torrential downpours. Varying temperature settings are bound to create flash floods other than those occurring during the regular rainy seasons. Research findings reveal that a two-degree increase in global temperatures will increase frequency of floods occurring in a century, by up to 5 times.

4. Fires and wildfires• De-forestation associated with farming and

construction of residential buildings bordering forest land, sparse dry vegetation, combined with drought and high temperatures, form an ideal setting for wildfires which rage over forests and bush lands for days together. Instances of wildfires are expected to be on the rise with the increase in heat wave conditions, which are commonly associated with the greenhouse effect. In the absence of green cover, lightning induced fires are also expected to be on the rise resulting in loss of human/wild life and property.

5. Increased volcanic activity

• Although there is no immediate danger of volcanic disaster, a research carried out by a team from University of Leeds, headed by Dr Carolina Pagli, reveals that melting glaciers in Iceland and other polar regions have reduced the mass of the Arctic ice-cap, and hence the pressure exerted by the ice on the land beneath it. Absence of sufficient pressure, allows the rock deep within the Earthâs surface, to melt easily and the extra ��magma be thrown up through the active volcanoes.

El Niñois the warm phase of the El Niño

Southern Oscillation (commonly called ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific (between approximately the International Date Line and 120°W), including off the Pacific coast of South America.

CAUSE OF El Niñohappens when weakening trade winds

(which sometimes even reverse direction) allow the warmer water from the western Pacific to flow toward the east. This flattens out the sea level, builds up warm surface water off the coast of South America, and increases the temperature of the water in the eastern Pacific.

LA Ni·ña• a cooling of the water in the

equatorial Pacific that occurs at irregular intervals and is associated with widespread changes in weather patterns complementary to those of El Niño, but less extensive and damaging in their effects.

CAUSE OF LA Ni·ñacaused by a build-up of cooler-than-

normal waters in the tropical Pacific, the area of the Pacific Ocean between the Tropic of Cancer and the Tropic of Capricorn. Unusually strong, eastward-moving trade winds and ocean currents bring this cold water to the surface, a process known as upwelling.