Drought, Monsoon, and El Nino – Their Mutual Relationship In The Indian Context
Monsoon brings showers and cheers to India. If it fails, it is a disaster both for people and economy. This year all forecasts of good monsoon have been belied and government is preparing to combat drought.
Thankfully we have enough food reserves to meet emergency requirements. Last year India produced record 252 million tonnes of foodgrains. Lot of it will be eaten by rats and left to decay in open spaces of FCI but that is another issue.
Monsoon faithfully arrives at the shores of Kerala every year in the month of June. Its arrival is sometimes disrupted by a phenomena called El Nino which occurs in Eastern Pacific, near the shores of Peru.
Already it is predicted that El Nino will occur this year, and this is a bad news for India and neighbouring countries. El Nino makes Monsoon weak, and kills it.
If Monsoon fails, farmers and policy makers in India will have tough time. But it is farmer who suffers more. Government declares drought, and announces financial packages and relief measures – which we know hardly reaches people.
Drought is a serious natural hazard that has severe implications for the affected region.
It can be defined as:
” a protracted period of deficient precipitation resulting in extensive damage to crops, resulting in loss of yield”
In more technical terms it is defined as:
“ a period of abnormally dry weather sufficiently prolonged for the lack of water to cause serious hydrologic imbalance in the affected area”
Indian Commission on Agriculture(1976) classified droughts into three categories:
1) Meteorological: when there is significant decrease in precipitation from normal over an area (i.e. more than 10%)
2)Agricultural: situation where amount of moisture in the soil no longer meets the needs of a particular crop.
3)Hydrological: it manifests from prolonged meteorological drought results in depletion of surface and ground water supplies.
Indian Meteorological Department declares a year as drought hit when rainfall received is deficient by 20% or more of normal rainfall.
Drought affects crop yield, carrying capacity of livestock, water scarcity – especially drinking water. It also results in decreased water table diminishing groundwater and also surface water essential for agriculture and water supply to cities.
Drought has resulted in mass migrations of people and cattle in many parts of the world. Some have resulted in social unrest – fight for food and water.
Effect of deficient rainfall is already evident in India in the power sector. There is decreased power production thanks to empty dams and rivers; also some thermal power stations need water to produce steam, and they are also affected.
The effect of drought is catastrophic to wildlife – as it results in wildfires, and also straying of wild animals into human habitats which end up being killed.
Very recently India suffered from droughts in 2002 and 2009. In 2002, there was 19% rainfall deficiency and 29% of India was hit. In 2009, there was 27% rainfall deficiency and it was one of the worst droughts in three decades.
To understand effect of El Nino on Indian Monsoon, we can imagine a situation first: we have Dubai in the west and Mumbai in the east. Both are financial and economic hubs. That is in normal years and in normal times.
Now assume, for our example sake, that Mumbai suddenly warms up – in the financial sector. There is a boom in realty, equity markets, and bollywood.
Meanwhile, Dubai sheikhs are content in investing in their own city. But, Mumbai has become too attractive to neglect. So they divert their investments to Mumbai, bleeding Dubai economy.
Monsoon requires rain bearing clouds and a wind system called trade winds to drive them towards Indian sub continent. In the Eastern Pacific, like Mumbai of our example, a situation arises once in 3-7 years when its temperature increases above normal. This disrupts trade winds and pressure systems of the western Pacific and Indian ocean.
These western winds move toward Eastern pacific carrying with them moisture. And Monsoon bleeds. (thing is high temperature in Eastern Pacific creates low pressure, and winds always move from high to low pressure regions – here, Monsoon winds represent high pressure winds)
This unusual phenomena results in drought in India and copious rainfall off the coast of Peru which is actually a desert.
Scientists are still understanding the complete mechanism of both Monsoon and El Nino. What we know better is their consequences on our economy and people.