what is meant by disaster explain drought and flood
Answers
Answer:
Like all living organisms, human beings need water to survive. ... Droughts occur when an abnormally long dry period uses up available water resources. Floods happen when watercourses or rain swallow up land that is usually uncovered. These natural disasters are often made worse by human action.
Answer:
A drought or drouth is an event of prolonged shortages in the water supply, whether atmospheric (below-average precipitation), surface water or ground water. A drought can last for months or years, or may be declared after as few as 15 days.[1] It can have a substantial impact on the ecosystem and agriculture of the affected region[2] and harm to the local economy.[3] Annual dry seasons in the tropics significantly increase the chances of a drought developing and subsequent bush fires. Periods of heat can significantly worsen drought conditions by hastening evaporation of water vapour.
Drought is a recurring feature of the climate in most parts of the world.
Many plant species, such as those in the family Cactaceae (or cacti), have drought tolerance adaptations like reduced leaf area and waxy cuticles to enhance their ability to tolerate drought. Some others survive dry periods as buried seeds. Semi-permanent drought produces arid biomes such as deserts and grasslands.[4] Prolonged droughts have caused mass migrations and humanitarian crisis. Most arid ecosystems have inherently low productivity. The most prolonged drought ever in the world in recorded history occurred in the Atacama Desert in Chile (400 Years).[5]
Drought affect food production and human society, so they are considered a disaster, of natural, supernatural or human cause (which itself could be supernatural causes, malediction, sin, ...). It is among the earliest documented climatic events, present in the Epic of Gilgamesh and tied to the Biblical story of Joseph's arrival in and the later Exodus from Ancient Egypt.[6] Hunter-gatherer migrations in 9,500 BC Chile have been linked to the phenomenon,[7] as has the exodus of early humans out of Africa and into the rest of the world around 135,000 years ago.[8] Rituals exist to prevent or avert drought, rainmaking could go from dances to scapegoating to human sacrifices. Nowadays, those ancient practices are for the most part relegated to folklore and replaced by more rational water management.
Explanation:
A flood is an overflow of water that submerges land that is usually dry.[1] In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health.
Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting in some of that water escaping its usual boundaries,[2] or it may occur due to an accumulation of rainwater on saturated ground in an areal flood. While the size of a lake or other body of water will vary with seasonal changes in precipitation and snow melt, these changes in size are unlikely to be considered significant unless they flood property or drown domestic animals.