Cold across North India and Climate Change

Extreme cold temperatures and fog are a regular feature in the months of December and January across North India. Every year in December and January temperatures drop to around 2 to 4 degrees with the maximum around 18 degrees. However, this winter has seen maximum temperature sub-10 degrees.

The cold condition

It is said to prevail with the maximum temperature remaining 4.5 degrees below normal. Temperature which is 6.5 degrees below normal is classified as a severe cold day. Cold conditions have prevailed from December 15 while intensifying from December 21. December 25 was the most intense cold day with temperatures falling 7 to 12 degrees below normal. According to scientists there is nothing unusual as per the climatic conditions which influence temperatures. Cold waves arrives through the western disturbance wind system, from the west and is responsible for rainfall in the Northern & Northwestern areas after picking moisture from the Mediterranean Sea. Other factors involved include snowfall which happens in states of J&K, Ladakh and Himachal Pradesh. All these factors combine to produce variable winter conditions.

Cold wave conditions prevail in areas of J&K, Afghanistan, Tajikistan, Turkmenistan and Northern Iran. The average temperature in these areas range from 1 to 5 degree below normal and adds to the cold bring brought by Western disturbances.

Causes

1) Effect of climate change : Instances of such extreme climate is becoming frequent due to climate change and is being witnessed around the world. The frequency as well intensity of heatwaves and cold waves have been increasing and is predicted to increase. Scientists are also of the view that climate change is bringing uncertainty in weather pattern and is becoming difficult to predict.

2) Low clouds : The cold has also been triggered due to low status clouds which are blanketed over a stretch of 500 to 800 km , affecting North India. These clouds are formed at a height of 300 to 400 meters from the surface block the sunlight leading to extended cold.

3) Western disturbance : Moderate to intense western disturbances have contributed to severe cold. Besides this, the flow of north westerlies have further added to the cold factor. With passing of western disturbances, the month of December have also witnessed fog, haze and rainfall all over North India.