NATURAL DISASTERS

Natural Disaster

                “Any natural phenomenon which may cause loss of life and property for man is called Natural disaster”. Volcanism, landslides, desertification, floods, cyclones, earthquakes and forest fires are such natural phenomena which cause destruction for mankind. Let us have a look on these natural disasters.

1.     Volcanism

        The formation of molten rock material (Magma) inside the earth and the process of its coming out on the earth surface is called Volcanism. The magma when comes on the surface of earth is called lave and it burns and destroys everything that comes in its way. Sometimes it comes out with an explosion and causes an earthquake. Sometimes volcanic ash also comes out with lava and gases during volcanism. This ash may rise in the atmosphere up to several miles and causes environmental pollution.

Volcanism in Pakistan

        Pakistan is fortunate that even lying in an active vibrant region, no dangerous and active volcano lies within its boundaries. However some volcanic activates have been traced in some places of Hindu Kush mountain ranges and Baluchistan.

Safety measures

        To mitigate loss of life and property in areas vulnerable to volcanism, an integrated monitoring system of volcanoes has been adopted throughout the world. In case of emergency, a warning is declared in the hazard zone to make people prepared to combat the disaster.

2.     Landslides

        Down slope movement of soil and weathered rock material under the influence of gravity is called landslide”. It may create an impact in many ways. It may cause loss of life and property. It may damage the construction severely. It may damage the construction severely. It may block the roads and damage the communication lines. It may block the flow of rivers i.e. the creation of Arababad Lake in Gilgit is the result of river blockade by landslides. It may disturb the agricultural productivity in the affected areas.

Landslides in Pakistan

        The northern areas of Pakistan are affected by landslides during the rainy season. Due to the construction of roads the slopes become unstable and vulnerable to landslides. Karakoram highway which connects Pakistan to China often remains blocked due to landslides. The unchecked tree cutting in mountainous areas of Pakistan is also a main cause of landslides.

Safety measures

        Methods of slope stabilization can be adopted in areas vulnerable to landslides to reduce their effects. Impacts of landslides can also be reduced by lowering the water table underground, by improving the irrigation system, by avoiding construction, by stopping unchecked tree cutting and by growing trees in the affected areas.

3.     Desertification

        The extension of deserts at the expense of cultivable lands is called desertification. Although climate chances have always favored the process of desertification, but human induced activities, especially after the industrial revolution are very much responsible for increasing desertification. Due to this menace, agricultural production and usable water resources are depleting and migration of humans and wildlife from the affected areas in increasing. As a result shortage of food, drought and increase in poverty at local level may occur.

Desertification in Pakistan

        Pakistan is situated in warm and dry climatic region where the annual amount of rainfall is less than 25 centimeters. Arid to semi-arid weather conditions prevail in almost 80% area of Pakistan. The main cause of desertification in Pakistan is unsafe and poor ways of cultivation which result in soil erosion, lapse of fertility, and continuous drop in biodiversity.

Safety measures

        To combat desertification, tree plantation can favor in two ways. Firstly, it reduces desertification by keeping weather conditions moderate. Secondly it acts as hurdle to stop the spread of desertification towards cultivable areas. The use of organic fertilizers can enhance the fertility of land. People can be made aware about desertification and methods to stop it. Unchecked cutting of trees should be discouraged and modern ways of cultivation and irrigation should be adopted to stop desertification.

4.     Floods

        An overflow of river water out of its channel, which may cause damage to the nearby settlements, is called flood. It is considered a natural disaster because it may be a cause of social and environmental degradation. It can damage any constructional frame work, uncommented housing and buildings without deep foundations. It may destroy bridges, roads, communication lines, crops, farms, orchards, livestock and cultural monuments as well. Loss of lives especially of women, children and aged can occur, along with the spread of diseases and epidemics.

Floods in Pakistan

        Pakistan has a natural system of rivers flowing out of the northern mountain ranges. These mountain ranges are a home of huge glaciers outsides the polar areas. Melt-water streams from glaciers feed these rivers. The upper plains of these rivers are situated in the rainy monsoon region. In summers the monsoon rains along with the melt water streams from glaciers cause heavy flooding in the rivers of Pakistan.

Safety measures

        Awareness about the flood risks should be given to the people of areas vulnerable to floods. Evacuation plan should be prepared to get people out of the area safely. Electricity and gas supplies should be disconnected to avoid any accident. Camps should be established in safe areas to provide shelter and food to the affecters. Proper arrangements should be made for the return of affecters to their homes. Efforts should be made on governmental and non-governmental side for reconstruction of houses and rehabilitation of the affecters.

5.     Cyclones

        Cyclone is a system of swirling winds which has low pressure area in the center. The winds tend to circulate toward the center and produce rain with thunder and lightning. Wind speed exceeds up to 200 kilometers per hours. The winds have erosive power which destroys everything that comes in their way. Cyclones produce continuous rainfall in a short period of time which may cause flooding and loss of life and property. In coastal areas huge sea waves called storm surges are generated which may cause destruction on a large scale.

Cyclones in Pakistan

        Arabian Sea lies in the south of Pakistan. In Indian Ocean, this is an important area of the origin of tropical cyclones. These cyclones affect the coastal areas of Pakistan. Thatta and Badin in sindh, while jeewani, Gwadar and Lasbela in Balochistan are the main areas affected by the cyclones. Inadequate construction methods and inferior construction material, absence of laws of land use, lack of awareness of the local people, lack of education and poverty are the main causes of destruction caused by cyclones.

Safety measures

        Construction of resistant houses should be made possible. Forecast management system should be established in areas vulnerable to cyclones. As soon as the warning is given, arrangements should be made to shift the livestock and house hold items to safe places. Evacuation system should be established and mobilization of volunteers in the affected areas should be made possible. In case of evacuation, the house should be sealed after disconnecting power supplies. A risk map should be prepared about the estimation of extent and storage of drinking water, food, candles, matches and first aid material should be made possible. Keep in touch with radio and report to emergency rescue centers established by the government.

6.     Earthquakes

        Sudden and intense vibration of the earth crust is called Earthquake. As this is a sudden movement without any pre-occurring symbols, prediction of earthquake is not possible. Earthquakes destroy human settlements, buildings and infrastructure i.e. bridges, roads, railway lines, pipelines, water tanks and communication etc. indirect damages include fire, loss of water reservoirs, and landslides etc. the most unrecoverable damage caused by the earthquake is the loss of valuable lives.

Earthquakes in Pakistan

        Geologically Pakistan lies in an active zone at the margin of three tectonic plates. Indian plate is converging with the Eurasian plate in the north and Arabian plate in the west. The geologic result of this convergence is the formation of Karakoram, Himalayas and the Hindu Kush mountain ranges in the north and northwest. This convergent boundary is also responsible for the occurrence of earthquakes in Pakistan and adjacent areas.