Geography Exam Notes

Topic 1 - Global Warming:

1.     Why is the Greenhouse Effect such a problem when it is a naturally occurring process anyway?

The greenhouse effect is a natural process that manages to keep our planet warm enough to maintain life. If we didn’t have it the earth’s average temperature would fall below 0^oC and without liquid water, there are a small number of life forms that would have been able to survive. It is a problem because humans decided to build things along coastlines before they knew it was happening. Our human-caused emissions of greenhouse gases that can be from cars, cattle farm and factories are causing the planet to heat up faster than what it is meant to be naturally. Due to this, we are making the ice caps melt faster (causing floods) than when it naturally was meant to happen. A warmer climate will change how we grow our food so our croplands will eventually need to change. With a warmer climate, many species will die because their habitat won’t be liveable anymore.

2.     What are the Greenhouse gases?

The greenhouse gases are water vapour, carbon dioxide, methane and nitrous oxide.

3.     Outline the human activities that produce these gases?

Water Vapour: No contribution from human activities

Carbon Dioxide: Deforestation, burning fossil fuels (coal, oil and gas)

Methane: Rice paddies, ruminant animals (cattle sheep), garbage dumps and landfill sites and the burning of fossil fuels

Nitrous Oxide: Chemical fertilisers, burning vegetation, industry emissions and burning fossil fuels.

4.     El Nino and its effects on Australia and South America.

El Nino is associated with warmer than usual central and eastern tropical Pacific Ocean temperatures. . The effects of El Nino result in drier conditions in Australia/Asia region which increase the probability of bush fires and drought (especially from June-August). El Nino creates increased rainfall across the east-central and eastern Pacific Ocean. Along the west coast of South America, El Nino reduces the flow of cold, nutrient-rich water that contains a large fish population. The sea birds eat these fish and the sea birds droppings support the fertilizer industry. In result, El Nino causes the loss of many fish which affects the birds, which affects us.

NOTE:

-        What is El Nino? à A wind that blows from south to west from South America’s west coast to Australia’s east coast (causing a drier winter and spring in Victoria)

-        What is El Nina? à  Is high rainfall in winter and spring.

-        Peruvian fisherman would prefer cooler ocean currents as fish wouldn’t die as much.

5.     What are the harmful effects of climate change? Problems.

Some of the problems will be:

-        Rising temperatures (more floods, more severe droughts, bush fires, heat waves and average temperatures of 35^oC.

-        Changing Oceans (warmer oceans bleach coral and eco-systems will suffer due to acidic water as the ocean will have to absorb more heat and…