How to write my school essay on ‘drought’

To write my essay on this, I need to know what is drought, how and what causes it and what are the results of drought. Drought is a period or condition of unusually dry weather,when there is no precipitation or rainfall. Drought is caused when there is no rainfall. It may be due to difference in air pressure or barrier like mountains which can prevent wind from blowing moisture to needed regions. When there is a drought in an area there is water scarcity. This results into poor crops growth and ultimately famine.
Droughts can persist for several years. Even a short but intense drought can cause significant damage to crops, animals and human life. In fact it will effect the whole ecosystem.
Water is needed for plants and vegetation to grow. We all animals depends directly or indirectly on these plants, so loss of plants and crop will result in lack of food and water for all. Ultimately drought will result into reduced crop, and even forest productivity, reduced water levels, increased fire hazard, increased livestock and wildlife death rates, and damage to wildlife and fish habitat. A reduction in crop productivity usually results in less income for farmers, increased prices for food, unemployment, and migration of birds, animals and humans.
Droughts will even increase the diseases. In human malnutrition will be easily visible. Plant diseases and soil erosion will also increase.