GCSE Geography Unit 1 - Challenges for The Planet

Challenges for The Planet

Why has the worlds climate changed since the last ice age?

Solar Output: Energy that comes from the Sun. Measurements that have been taken show that the amount of energy reaching the Earch is slowly decreasing. The activity of sunspots on the Sun's surface affects solar output. The more sunspots there are, the more energy there is reaching the Earth.

Orbital Geometry: The Earth's orbit around the Sun varies from circular to elliptical every 95,000 years. When the orbit is circular cold periods tend to happen and when it is elliptical there are more warmer periods.

Volcanic Activity: Volcanic eruptions release large amounts of sulphur dioxide and ash into the atmosphere. These act like a cloak and reduces the amount of solar energy reaching the Earths surface.

Change in Atmospheric Gas: There is a clear relationship between carbon dioxide in the air and temperature fluctuations. Carbon dioxide is the main gas responsible for the greenhouse effect. This keeps heat within the Earths atmosphere by absorbing solar radiation. This increases global temperatures.

The causes of current climate change on a local and global scale:

Fossil fuels: When fossil fuels such as coal, oil and natural gas are burnt they produce carbon dioxide which is contributing to the greenhouse effect causing the climate to change. There has been an increase in the burning of fossil fuels in countries such as China. Countries like this that are developing rapidly need to burn these fossil fuels for energy. There has been an increase in global car ownership which means more oil is used, which leads to the amount of carbon dioxide in the air to increase

Methane: Methane contributes allot to the greenhouse effect and is one of the main gases involved. This level of Methane is rising rapidly in the air over the past decades but why? There has been an increase in the number of cattle for meat. Cattle produce methane as they eat their food. There has been an increase in the number of rice because populations are growing and the demand for it is increasing. Rice is grown in marshy conditions which released methane.

The negative effects of climate change:

Crop Farms: If temperatures continue to rise it will have an effect on food production. In India, there will be a 50 percent decrease in the amount of land available to grow wheat. This is due to hotter and drier conditions/weather. In…