The India Meteorological Department (IMD) recently stated higher day temperatures prevailed in parts of the country – maximum temperatures are above normal by 3-5 degree celsius in northwest, central & west regions –could have an adverse effect on the standing wheat crop, which is approaching flowering stage. To counter higher temperatures, farmers should provide light irrigation for wheat and horticultural crops, Mrutyunjay Mohapatra, Director General, IMD tells Sandip Das.
What are the causes of unusually high temperatures over the past week?
The prevailing temperature is near normal and slightly above normal over central and north-west India. It is at above normal level over eastern India. The maximum temperature was above normal by at least 5-8 degree Celsius over Gujarat and Maharashtra, Haryana, Punjab and parts of Uttar Pradesh. It was mainly because of anti-cyclone circulation centred over Gujarat which rotates the air in clockwise direction. When air rotates clockwise wind goes down and it gets compressed hence rise in temperature. Wind blows from Gujarat to northern states this heat got transferred toward north-west India. The temperature last week rose sharply. Thus temperature rose in Gujarat especially over Saurashtra and Kutch. Last year it occurred in March. That situation is not there now. The anticyclone has moved away towards Arabian sea. And hence temperature has fallen across states. The temperature will remain at the normal level till end of the month.
What could the impact of higher day temperature on the wheat crops?
The current above normal day temperature can have an adverse impact on the wheat and it may possibly impact horticultural crops as well. At this time of the year, wheat is at maturity stage. During the flowering and milking stage, if temperature rises, early maturity of crops takes place. Early maturity results in yield losses. To counter higher temperatures, farmers should provide light irrigation for wheat and for horticulture crops, mulching is suggested which reduces the release of water vapors from the soil.
Is formation of El Nino likely in forthcoming monsoon season?
As per our current prediction, during March-May, El Nino conditions will be neutral which implies that there will be no impact on weather patterns. When we move towards monsoon months, many models are suggesting development of El Nino conditions. These predictions are based on January and February data. These initial forecasts are not good climatologically globally. People depend on the more reliable forecast to be issued by us in April and we take into consideration the El Nino effect. Accuracy of the weather forecast is not there if it’s beyond 3-4 months.
What are other factors which impact the monsoon performance?
Besides El Nino, there are other factors such as Indian Ocean Dipole (IOD) and Euroasian snow cover that impact the south-west monsoon. IOD is currently at neutral. Positive IOD is good for monsoon. The current forecast says that the neutral condition of IOD will continue during the south-west monsoon months (June-September). Eurasian snow cover in January this year was the 9th lowest in the past 67 years. Eurasian snow has an inverse relationship with Indian monsoon. If the snow cover is less, it’s good for the Indian monsoon. The warmer climate in Europe makes the monsoon in India strong as the temperature difference between land and sea is higher.