08 Jan Western disturbances and rainfall in india (The Hindu, GS-1)
Western disturbances and rainfall in india- Today Current Affairs
Context– The continuous rainfall across Punjab, Haryana, Chandigarh, Delhi, north Rajasthan, west Uttar Pradesh in the last 3-4 were predicted by the Meteorological Department earlier itself. First, it was the jitters and now it’s the rains. IMD predicted that after a shivering cold surge, two successive western disturbances are likely to bring downfall to the corridor of North India and the central corridor of India in the days to come.
Western Disturbances: The Hindu Aalysis
Western Disturbances develop in the mid-latitude region (north of the Tropic of Cancer), not in the tropical region, thus they’re called mid-latitude storms or extra-tropical storms.
Extra-Tropical Cyclones are also called downtime storms and blizzards.
It’s a term given by an Indian Meteorologist for the rainfall miracle which is propagated from the West.
Western Disturbances are low- pressure systems, bedded in western winds (westerlies) that flow from west to the east.
The low pressure generally forms over the Mediterranean Sea and travels over Iran, Iraq, Afghanistan, and Pakistan before entering India loaded with humidity.
These humidity-laden western disturbances ultimately come up against the Himalayas and get blocked, as a consequence, the humidity gets trapped and rush is participated in the form of snow and rain over Northwest India and occasionally, other corridors of North India.
A normal of 4-5 western disturbances form during the downtime season and the downfall distribution and quantum varies with every western disturbance.
The word‘Western’refers to the direction from which they appear with regard to India.
The word‘ disturbance’ is used because the air within the low- pressure systems tends to be unstable or perturbed.
Occasionally, when western disturbances come more violent in the Indian Region, they can extend indeed up to 15 degrees north, performing in downfall up to north Maharashtra, Gujarat, and the entire Madhya Pradesh to the south.
How will the two Western Disturbances affect India?
Impact: The Hindu Analysis
North-West India receives most of its winter precipitation and pre monsoon rains from Western Disturbances only . This miracle is generally associated with a cloudy sky, advanced night temperatures, and unusual rain. If we go by some of the estimates say India receives almost 10% of its total periodic rainfall from these disturbances. Also disturbances bring snowfall and moderate to heavy rains in different parts of north india. India is a rain-dependent country and while the southwest thunderstorm covers most of India, the corridor of North India doesn’t get important rain from it. These regions depend upon snow and rain from western disturbance during the downtime season from November to March.
Rush during the downtime season has great significance in husbandry particularly for rabi crops including wheat, which is one of the most important Indian crops.
They start declining after downtime. These western disturbances move across North India in the month of April and may and sometimes thunderstorms in certain parts of northwest India are also activated by it.
During the thunderstorm season, western disturbances may sometimes beget thick clouding and heavy rush.
If the western disturbances are weak, will result in crop failure and water problems in north India states.
Strong western disturbances can help residents, growers and governments avoid numerous of the problems associated with water failure.
Casualties: The Hindu Analysis
Since western disturbances aren’t high- intensity rainfall systems, they aren’t generally associated with disasters but in recent history, it’s observed that this salutary rainfall miracle is decreasingly getting disastrous during the summer and thunderstorm seasons.
The 2010 rainstorm in Leh, in which 71 municipalities and townlets were damaged and 225 people failed was caused due to the western disturbances.
In September 2014, the Kashmir region suffered disastrous cataracts across numerous of its sections killing over 200 people and western disturbances were the cause of this.
Expert opinion on western disturbances is divided regarding the 2013 cataracts in Uttarakhand in which over 5000 people were killed, after three days of ceaseless downfall. While numerous believe that Uttarakhand cataracts may have passed due to relations between western disturbances and the summer thunderstorm, numerous others believe that western disturbances and thunderstorms occur in fully different time frames.
Significance of Western Disturbances: The Hindu Analysis
The western disturbances affect rainfall conditions during the downtime season up to Patna (Bihar) and give occasional downfall which is largely salutary for the standing rabi crops, (wheat, barley, mustard, gram, lentil,etc.).