Direction (Qs.1 to 8): Read the passage carefully and choose the best answer to each question out of the four alternatives.

Climate change is the seasonal changes for a long period of time in the world. These climate patterns play an important role in shaping natural ecosystems, and the human economies and cultures that depend on them. For example, the changes in climate can affect how people, plants and animal life, such as food production and health risks. As the earth’s climate is dynamic and always changing through a natural cycle, the world is now worried about the changes that occurring today have been speeding up and seriously affecting human’s lives. All across the world, people are taking action to prevent climate change. For example, in 2007, scientists from the International Panel on Climate Change (IPCC) predicted that warming oceans and melting glaciers due to global warming and climate change could cause sea levels to rise 7 – 23 inches by the year 2100. So, some islands and some small countries will be flooded by sea water and even disappeared very soon. Because of this, we must take action as soon as possible to try to solve this problem or to prevent the more serious climate changes occur. There are two main causes of climate changes – natural causes and human activities. Natural causes have influenced the earth’s climates such as volcanic eruptions, ocean current, the earth’s orbital changes and solar variations. The eruptions of volcanoes cause a cooling effect on the earth. When a volcano erupts it throws out large volumes of sulphur dioxide (SO2), water vapour, dust, and ash into the atmosphere. The volcano eruptions will affect the climatic pattern for years although the eruptions occur in a few days. The sulphur dioxide gas will reach the upper level of the atmosphere. The tiny particles, clouds of dust and ashes will block the incoming sun rays and this will leads to cooling at the atmosphere. This is because the bouncing of sunlight to space is cooling the atmosphere of the earth.

Furthermore, ocean current is one of the natural cause that affecting climate changes. The changes in ocean circulation will affect the climate through the movement of carbon dioxide into or out of the atmosphere. Moreover, another cause that affects climate changes is the earth’s orbital changes. The earth makes one full orbit around the sun every year. If there is not tilt we will not experience seasons. Changes in the tilt of the earth can affect the severity of the seasons. For example, if there is more tilt means we will experience warmer summers and colder winters and if there is less tilt means we will experience cooler summers and milder winters. Another main cause that leads to climate changes is human activities. From the 19^th century, the Industrial Revolution saw the large – scale use of fossil fuels for industrial activities. Therefore, they created many jobs for people. And many people moved from rural areas to cities. Many vegetation areas were cleared to become houses or factories for industries. Natural resources are being used extensively for construction, industries, transport, and consumption. All this has contributed to the rises of greenhouse gases such as methane and nitrous oxide in the atmosphere.