Monday, June 15, 2009

Monsoon 2009 - Current status :: IMD report

Government of India
Ministry of Earth Sciences
India Meteorological Department

Press Release
Dated 10th June, 2009

Subject: Monsoon- 2009: Current status

Onset and advance of monsoon
Southwest monsoon set in over Andaman Sea around its normal date, on 20th May. However, it set in over Kerala on 23rd May, about one week earlier than the normal date (1st June). IMD on 14th May issued forecast for onset of monsoon over Kerala on 26th May with a model error of ± 4 days.

Subsequent to onset of monsoon over Kerala, a cyclonic storm named AILA formed in the Bay of Bengal. It resulted in advance of monsoon over northeastern states and West Bengal and Sikkim. Thereafter, no fresh surge developed in the Bay of Bengal which could bring the monsoon into the eastern parts of the country. After a hiatus of about a week, monsoon further advanced along the west coast and reached upto Ratnagiri on 7th June. Kerala, Karnataka, Konkan & Goa have received widespread rains accompanied with very heavy falls during 5th to 7th June. However, there has not been further advance of monsoon after 7th June and its northern limit continue to pass through Lat. 17.0° N/ Long. 60.0° E, Lat. 17.0° N/ Long. 70.0° E, Ratanagiri, Gadag, Anantapur, Ongole, Kalingapattinam, Paradip, Balasore, Bankura and Gangtok.

The advance of southwest monsoon into different parts of the country is generally not a systematic and regular feature. It is always accompanied with surges in the strength of southwesterly winds over the north Indian Ocean. In association with each surge, the rainfall activity gets revived and the rain belt shifts north and northwest. After each wet spell, normally there comes a hiatus of about 6 to 8 days in which the rainfall activity gets subdued, and northward advance of monsoon is also halted.

Current Scenario

As per the latest meteorological conditions and the forecast of several Numerical Weather Predication Models, southwest monsoon activity is not likely to revive during next one week. Consequently, the advance of monsoon over east, north peninsular and adjoining central India will be delayed. However, occasional thunderstorm activity will continue. Under this scenario, maximum temperatures exceeding 40Âșc is likely over central, east and northwest India even with possibility of heat wave conditions over isolated pockets.

Changing weather may kill us off

Mumbaikars need to brace themselves for more disasters as extreme weather events such as the deluge on July 26, 2005, may not be a one-off event. The climate in Indian cities, like Mumbai, is warming up fast and this could be a recipe for more natural disasters, says the India Meteorological Department (IMD).

The regional IMD office at Mumbai analysed 100 years of weather data from 1901 onwards and found a rise of 1.62°C in the average maximum temperature. The report was submitted to the state chief minister on May 11.

In its report, Environmental Degradation, Disasters and Climate Change, the IMD team has argued that human activity induced environmental degradation was responsible for global warming.

“Our analysis shows that the 1990s witnessed three times more natural disasters, like floods and thunderstorms, than the 1960s. Even drought-prone districts such as Jaisalmer and Barmer in Raja­sthan suffered devastating floods in 2006…Since 1960s, expenditure on mitigation and reduction of such disasters has

increased nine-folds,” says R V Sharma, deputy director general of meteorology, Regional Meteorological Centre, during a recent press briefing.

Between early 20th and 21st centuries, Mumbai registered a mean maximum temperature rise of 1.62°C; this is a cause of great concern, Sharma says. It is not surprising that winters are giving Mumbai a miss, he added.

Is a rise of about 2°C over 100 years

really a matter of concern? Scientists warn such a rise has a direct negative impact on human health and food security.

There is scientific evidence to prove that an increase of 1°C in northern India’s hilly areas means wider malaria window. Mumbai is seeing a surge in malaria, but as of now, we cannot blame it on global warming.

“We have recently tied up with King

Edward Memorial Hospital, Mumbai, to find out how diseases like malaria, dengue and asthma are related to global warming and climate change,” says Rakesh Kumar, head of National Environmental Engineering Research Institute’s Mumbai office, at a public meeting on Climate Change and Mumbai.

Meanwhile, newspapers in Mumbai are full of reports on rise in malaria cases. Already 1,351 malaria cases have been reported till April this year. There were a total of 790

cases last year.

Though there is no clear pattern, Sharma claims that 2001 onwards rainfall over Mumbai has increased. This could be due to a change in the lapse rate or the rate of change of any meteorological element (temperature in this case) with altitude. The lapse rate

determines the growth of clouds.

“The lapse rate is increasing with the cooling of air in the upper atmosphere and warming of the lower atmosphere. With such a steep lapse rate, cloud formation will be rapid and there will be more thunderstorms. There will also be heavy precipitation. This explains why there were more thunderstorms and heavy rainfall in the past decade,” Sharma explains. Could a steep lapse rate be the reason behind cloud burst on July 26, 2005? The day when the city received 944 mm rainfall in just one day.

— Down To Earth Feature Service

Washed away

Global warming is changing

tidal action and forcing

islanders in low-lying areas to evacuate. In 2008, people from five islands in Papua New

Guinea — New Ireland,

Morobe, Manus, Bougainville, West and East Sepik and

Madang Provinces — were moved out fearing high tides. An estimated 50,000 people were affected. In 2003, the

island in south Pacific, sent a letter to the United Nations General Assembly, bringing to its attention, the “extreme

hardships” they have to suffer due to climate change and

variability and sea-level rise. Other South Pacific nations like the Kiribati, which is six feet above sea level, are slowly

submerging. In 2006, Kiribati’s President, Anote Tong, warned the neighbouring regions like Australia and New Zealand to prepare for a mass exodus from the archipelago. The number of people applying for a residence in New Zealand was 17,000 that year; more than four

times the number in 2003. Tong had set a timeline of 10 years, from 2006, before the island went under water.
Original from:: http://www.expressbuzz.com/edition/story.aspx?Title=A+changing+weather+may+kill+us+off&artid=/D5magZ49uc=&SectionID=f4OberbKin4=&MainSectionID=f4OberbKin4=&SEO=Climate+change&SectionName=cxWvYpmNp4fBHAeKn3LcnQ==

Key to monsoon revival now lies in Bay of Bengal

June 14 The monsoon has been stuck for exactly a week after it revived from the shock administered by Cyclone Aila, and is expected to stay as such for another three to four days.

This would delay its advance into major farming regions in the east, southeast and peninsular India, India Meteorological Department (IMD) said on Sunday.
TROUGH OF LOW

The only redeeming feature as on date was the presence of a trough of low pressure over north Bay of Bengal. The European Centre for Medium-Term Weather Forecasts sees some activity brewing here within the next five days.

The IMD said that increase in rainfall is likely along the west coast and over the Andaman and Nicobar Islands from Wednesday apparently as a prelude to the churn in the Bay.

To the peninsular west, a persisting offshore trough linking south Karnataka coast to Kerala coast would continue to cause fairly widespread rainfall over coastal Karnataka, Kerala and Lakshadweep.

The Regional Met Centre, Chennai, said in its update that rainfall occurred at many places over Kerala and at a few places over Lakshadweep and coastal Karnataka during the 24 hours ending Sunday morning.

Isolated rainfall occurred over Tamil Nadu, coastal Andhra Pradesh, Rayalaseema and interior Karnataka also.
MORE RAINS

Rain or thundershowers are likely at many places over Kerala and Lakshadweep, and at a few places over coastal and south interior Karnataka, coastal Andhra Pradesh, Rayalaseema and interior Tamil Nadu for two more days.

Isolated rain or thundershowers are likely over coastal Tamil Nadu, Puducherry, north interior Karnataka and Telangana.

Delay in monsoon over Bihar, Orissa, Jharkhand, Chhattisgarh, parts of Andhra Pradesh, Maharashtra, southern Gujarat, Madhya Pradesh and adjoining peninsular India has allowed heat wave conditions to develop.

On Saturday, the highest maximum temperature of 44.6 deg Celsius was recorded at Ganganagar. Severe heat wave conditions prevailed at isolated places in Vidarbha.

Meanwhile, Dr Karumuri Ashok, Senior Research Scientist at the Asia-Pacific Climate Centre, Busan, South Korea, has clarified that the forecast for a weak El Nino and positive Indian Ocean Dipole (IOD) over the next months was ‘experimental’ in nature.
MODEL DIFFERENCE

The APCC predictions for El Nino and IOD are only in research mode, produced once a season for the next six-months with collaboration from several research centres to arrive at a consensual coupled model prediction.

The APCC’s ‘operational’ prediction (based on mathematical models of atmospheric motions alone) is different from this ‘coupled’ (ocean-atmosphere) prediction, Dr Ashok informed Business Line.

“As per our operational prediction, rainfall signals for India for June-July-August are positive to near normal everywhere, unlike the coupled prediction,” he said.

The equatorial Pacific would still need to be constantly watched before any final word could be said about the development of any major weather-altering event.
‘NEUTRAL’, FOR NOW

Meanwhile, the Climate Prediction Centre (CPC) of the US National Weather Services said in its June-8 update said that ‘neutral’ conditions were present in the equatorial Pacific Ocean.

But current observations and dynamical model forecasts indicated that conditions were favourable for a transition to El Nino conditions during June-August.

Since the beginning of May 2009, positive sea-surface temperature (SST) anomalies have been observed across the equatorial Pacific.

During the last four weeks, equatorial SSTs were above-average across much of the equatorial Pacific Ocean, with the largest positive anomalies evident in the eastern and western Pacific, it said.

Original:: http://www.thehindubusinessline.com/2009/06/15/stories/2009061550490300.htm