Sunday, January 22, 2012

No respite from biting cold till March; February maybe winter at its harshest; above normal monsoons, floods highly likely this year

Over 200 dead and increasing public demands to declare cold as natural calamity and for avoidance of elections during winter are just few of the many warning symptoms of India's failure to adjust to a rapidly cooling world. We provide an overview to some of the chaos this creates:
New Delhi: Republic Parade to be affected by fog, cold?

If you were flying in or out of Delhi you couldn't have chosen a worst time of the year to do so.  Near zero visibility, hour-long closures of air space for Republic Day practice and VIP movements led to the season’s worst disruptions at Indira Gandhi International airport yesterday. Almost 300 flights were delayed by 2-8 hours while 28 were canceled and 19 diverted, as departures were held up completely between 7am and 9am, the peak operation time for domestic flights.

The Republic Day (26th January) preparations in New Delhi have been hit by heavy fog and cold. But school children, adults and the military braved intense cold wave and fog to rehearse for the Republic Day parade for more than a month. Their determination may go in vain as the weather gods are sending the western disturbance, mercifully milder, the third for the month to hit India tomorrow. The western disturbance as an upper air cyclonic circulation now centers over northeast Afghanistan and adjoining Pakistan, persists and now extends upto 4.5 kms a.s.l. The cyclonic circulation over Haryana and adjoining west Uttar Pradesh also persists and now extends upto 3.6 kms a.s.l. The above two system are forecasted to move north-eastwards by the Indian Met office. 

The next western disturbance’s arrival phase will, however, lift minimum (night) temperatures a bit. But ground frost has been forecast for this period in the wake of the cold, dense air sinking to the ground level after a prevailing western disturbance has passed to the east. It will take the ascending motion of at the vanguard of the incoming western disturbance to replace the cold air. Fog conditions should therefore reduce by Sunday morning. Clear sky will keep the night temperatures will be around 5-6 deg C during the weekend. But Delhi may face intense cold and fog from Republic Day affecting the parade. If so, this would be the first time in several decades!
Uttarakhand: Cold Wave to affect polling turnout?

This hill state is to go to polls on 30th January. Most of the political parties including the incumbent BJP government have already expressed reservations to the election commission about the January-end polling. "We communicated to the commission but were told that the commission has studied the winter cycle of the last fifty years," Khanduri, the state's chief minister said. With less than ten days left for the polling campaigning is yet to pick up in the hills of Uttarakhand even the lower ranges of the Shivaliks have been snowing, forcing both the candidates and public indoors.  

There are 9744 polling booths in Uttarakhand and a petition in the Supreme Court last week had urged postponement of the elections as nearly 30 per cent of these booths are in snow bound areas. There are even places like Harsil in Uttarkashi district where the polling parties have to carry voting machines and their luggage on mules and horses and walk for days to conduct elections. The court refused to interfere; the commission is hopeful that the weather would clear up by the polling date. Chief Electoral Officer, Uttarakhand Radha Raturi told The Hindu, "We have information that after January 23 weather will improve, so polling on the 30th should not be a problem."  In constituencies spread over vast hilly terrain where margins of victory at times are a few hundred votes, a low voter turnout can affect the outcome of polls and political parties are obviously worried. 

While states like Uttarakhand may get a slight relieve from fog and cold conditions from the 23rd, this would most likely be a temporary reprieve, as the effects of the next western disturbance will bring back the cold, snow and fog from around the 25th which would throw a spanner in the smooth conduct of the polls in the state on January 30th. The last round of assembly polls demonstrated voter turnout around 80%. This time, in states like Uttarakhand, we may see turnout not more than 60%. How low it gets, would be interesting. If it falls to 30% levels, then the Election Commission may attract alot of flak to continue the scheduled polls despite public opposition to this decision.
Rajasthan: Demands for Cold Wave inclusion as a Natural Calamity increases

Chief Minister Ashok Gehlot wrote to Home Minister P Chidambaram, demanding inclusion of frost and cold wave in the category of natural calamity. He said that if cold wave and frost are included in the category of natural calamity, it will help farmers in getting compensation for their damaged crops. The state opposition party, the BJP too demanded change of norms by the Centre and inclusion of cold wave and ground frost in the disaster list. BJP's Rajasthan unit office bearers, MPs and MLAs marched towards the Raj Bhavan (governor’s residence) and submitted a memorandum to the Governor S K Singh to this effect. "We have demanded that the Central government should amend its disaster list and include cold wave and ground frost in it," a BJP spokesperson said.

Rajasthan reeled under intense cold as Mount Abu, the state’s only hill station, experiencing a chilling night at -2.2°C. Dabok was also cold at 3.2 degree Celsius. Vanasthali, Sawaimadhopur, Pilani and Bundi recorded a minimum of 3.4, 4.8, 5.5 and 5.8 degree Celsius respectively while other parts of the state recorded night temperatures in the range of 6.4 degree Celsius to 10.5 degree Celsius.

South India: Reprieve from Cold Wave maybe short lived
Last week’s cold wave in South India that plunged temperatures to 100 year lows in many areas may have been dismissed a freak by the Indian Met office. Though temperatures are rising again, this can radically change after the 25th of this month. According to the blog Indian Weatherman: “A strong anti-cyclone is expected to form over N-E Andhra on 22-Jan... which will fan more N-westerlies towards South. (see map on left).  Anti-cyclones are formed when clear, dry air masses cool from a loss of infrared radiation, while little sunlight is absorbed to offset that infrared cooling.

As long as the anti-cyclone persists and remains strong, this could bring back cold wave conditions after 26th January to South India. This will however lead to a marked rise in min and max temp in Central India and min temp can settle close to 20C as against the persisting ~10C. Mango production is expected to take a huge hit.

So why is South Asia experiencing a prolonged & harsh winter?
The colder than normal, if not harsh winter in South Asia can be attributed to the combined effect of La Niña and the Indian Ocean Dipole (IOD), oceanic processes in the Central Pacific and Indian Ocean, respectively. Both factors tend to draw the cold air of higher latitudes to the tropical and sub-tropical Asia. 
La Niña conditions occur when eastern equatorial Pacific water becomes colder than normal. It is the reverse of El Niño, and sends such a strong signal that this single event can shatter the weather pattern all over the globe. Now the Central Pacific water is more than 1C colder than normal. 

The La Niña appeared to have peaked this month with NIÑO3.4 values at 0.8 deg C and Southern Oscillation Index (SOI) value at +12.8. The La Niña has started to markedly weaken with most models suggesting an end of the event during the coming autumn season. 

But as the late John Daly, a great among climatologists, observed, the Southern Oscillation is the primary driver of year-to-year global temperature, with a 6 to 9 month lag time. Accordingly, while the La Niña has peaked and weakening, its impact on global temperature is just starting to kick in. We are now seeing the La Niña effect beginning to be the prime driver of winter in the Northern Hemisphere. Winter had been mild within the mid-latitudes till mid January because Arctic Oscillation (AO) and its cousin North Atlantic Oscillation (NAO) had been in their positive phases. But a pattern change has taken place with winter intensifying despite the AO and NAO remaining largely positive as seen below as the La Niña is beginning to swamp their effect :
 Joe D'Aleo reports: "The Northern Hemisphere came hard out of the box early with well above normal snow. Then a strng [polar vortex took over and preventing the snow from expanding very far into the lower 48 and west into Europe. A breakdown of that vortex is underway and snow has started to fall in the northern US and in Europe. Here is the current snowpack."
 The AMSU satellite data besides shows that in trapping hot spot itself - 400mb or 25,000 feet levels - the atmosphere is at its coldest for the entire decade! Temperatures in the sub-surface of the eastern tropical Pacific have continued to cool over the past two weeks. The map for the 5 days ending 17 January shows the volume of water in the sub-surface of the eastern tropical Pacific more than 4 °C cooler than usual for this time of the year. With the atmosphere and sea surface temperatures freezing cold, it is a matter of time land masses follow.
IOD on the other hand is a seesaw like temperature pattern of the eastern and western Indian Ocean with a respective warmer and colder zone. IOD was in negative phase till last week but the index has since then switched to neutral - the index value for the week ending 15 January was −0.1. The model ensemble mean indicate that it would rebound slightly before turning weakly negative next month, progressively strengthening right through September.  This means the beginning to the end to East African drought! 
The Indian Ocean Dipole (IOD) is the leading mode of precipitation in the Indian monsoon region in the absence of the El Niño Southern Oscillation (ENSO) ENSO variability. It is a measure of the east-west heat distribution across this ocean. Accordingly, the South West Monsoon of South Asia is driven, at least in a big part, by heat energy entering the atmosphere from the Indian Ocean. Therefore, it should follow that the behavior of the South West Monsoon, including distribution and amount of rainfall, would largely hinge upon the temperature state of the Indian Ocean (the IOD). A negative Dipole is more likely to concurrent a La Niña than an El Niño and this year is an example. The sea surface temperatures (SSTs) of Central Pacific model ensemble mean indicate that La Niña values should last till September this year. 

A positive IOD represents warming anomalies to the west of equatorial Indian Ocean relative to the east. It boosts a concurrent Indian monsoon. The IOD is negative when the western Indian Ocean has below-normal temperatures concurrent with an eastern Indian Ocean that is warmer than normal. The negative IOD normally tends to hinder the SW Monsoon. So as the IOD slips into its weakly negative phase, normally during the austral winter, rains over Indonesia and Australia are expected to be above normal while the Indian sub-continent experiences a weaker summer monsoon.

However, 2012 should be an abnormal year since it has a negative IOD occurring concurrent with the La Niña which is relatively a rare event as seen in the above table - occurring at a frequency of around 7 years out of every 100 years. 

To get an insight what kind of rainfall we could get for years where La Niña overlapped a negative IOD we can check out the monsoon data provided by the IMD website (here). What we find the La Niña effect swamps those of a negative IOD, each and every year classified within this category as tabulated below:  

What is more, in most of these years, the monsoon brought massive floods. Since weather events tend to repeat itself in cycles, we can expect above average monsoons accompanied by floods this year.


The cold wave we experienced so far in India can be considered just an appetizer. The main course of the cold wave will be served from now on viz. it is poised to intensify; death toll will spike and people’s miseries will increase.

Winter can be expected to stay at least until March, if not beyond it. "During this winter, northern part of the country is likely to be below normal. So, we may expect that at least in the extreme north, the temperature should be below normal up to end of February and then by March and all it should reach to a normal situation," said Director of Forecasting Division, Pune Weather Department, Dr. D. S. Pai. 
The Election Commission would end up probably vindicated for sticking to their decision not to change the 30th January poll date of Uttarakhand. This is because the state is likely to face a more intensified cold wave during February.

Though the IOD would turn negative shortly, India is most likely to receive above average monsoons enabling a bumper harvest with food commodity prices continuing to soften further. 

The speculation whether it would snow in New Delhi this season would remain alive. Due to increased convection, localized precipitation events can occur producing about 15-20% above normal precipitation during February and March. A snow in New Delhi headquartering warmists like the IPCC chairperson, Rajendra Pachauri; India’s premier environmental NGO, Centre for Science & Environment (CSE); WWF; Oxfam; ActionAid; ChristianAid etc would be a symbolic victory for the climate sceptic community in India. February may just give sceptics the icing in the cake - the battle we are winning already!

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