Tuesday, July 30, 2013

History revisited : Slideshow on the Darjeeling Disaster of 1950.

The Jun1950 Darjeeling Disaster

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Human memory of disasters is often flawed and very short-lived. As such it is important to chronicle and preserve these records as accurately as possible and the above slideshow on the ‘Jun1950 Darjeeling Disaster ’ is an effort this direction.
Not much data exists on the Jun1950 disaster which struck the Darjeeling district and whatever is available is, at best sketchy :-

  •   The ‘Report of the Expert Committee on Landslides in the Darjeeling Hills’ states that 127 people died, mostly in Darjeeling town. No information is available on casualty figures in Darjeeling district or in Sikkim.
  •   ‘Floods, Flood plains and Environmental Myths’, a CSE document, talks of a cloud burst in the Teesta valley which dumped 546mm of rain on 12Jun1950 whereas the official government website pegs the rainfall at 965mm for the whole month of June1950.
While rummaging through records for this event on the internet, I stumbled onto the ‘Annual Report of 1950’ of St Joseph’s School, Darjeeling which had a rather quaint account of the disaster – that of a student in the school and I have included it in the slideshow.
I also was extremely fortunate to discover that Mr Durga Das Pradhan of DAS Studio, Darjeeling, who had given me these photographs sometime back, was also the photographer who had taken these images more than 60yrs ago! As such I was lucky that he could pinpoint the locations where the landslides had taken place in the vicinity of Darjeeling town.

Praful Rao,
Darjeeling district

Sunday, July 21, 2013

All about rainfall : From the Telegraph today (21July2013)

North’s rain gain is east’s loss

New Delhi, July 20: A torrential downpour that washed Delhi today and the rainfall that devastated Uttarakhand last month could be portents of shifts in the monsoon’s behaviour that have also shown up as rainfall deficits in eastern India, scientists say.
Eastern India is the only zone among the country’s four meteorological regions that has as a whole experienced deficit rainfall since the monsoon season started this year, while the traditionally arid northwest is unusually wet.
Bengal’s Gangetic plains have had rainfall 30 per cent below the expected average so far, delaying preparation of paddy seedbeds.
While Uttarakhand’s extreme event on June 16-17 may explain its 74 per cent excess rainfall, Uttar Pradesh, Punjab and even eastern Rajasthan have recorded high above-average figures.
“India’s north appears to be stealing rain from the east,” said Madhavan Rajeevan, a senior atmospheric scientist and programme director at the National Monsoon Mission, a research initiative launched last year by the Union earth sciences ministry.
While the movements of moisture-bearing winds and low-pressure systems may explain the heavy rain in the north, scientists say they are intrigued by recent trends pointing to persistent rainfall deficits in the east.
“We’ve seen rain deficits in parts of the east and Northeast over the past five years but we don’t fully understand the underlying mechanisms or even whether this is a long-term trend,” Rajeevan said. “We’ll need more observations, more research.”

Full article is here

Praful Rao,
Darjeeling district

Saturday, July 20, 2013

STH Stormwatch ( 20 July 2013) : Reporting a Low Pressure Area (LOPAR) in Bay of Bengal

As a part of  "STH stormwatch", we maintain a watch on the weather activity in the Bay of Bengal with a view to provide advance information and timely warning. The report below is a part  of this endeavour:-

"The  low pressure area  over northwest Bay of Bengal and neighbourhood persists. 
Associated upper air cyclonic circulation extends upto mid­tropospheric level tilting 
southwestwards with height also persists."
Source : IMD

We will post updates on the LOPAR if necessary.

Rohan Rao
Dist - Darjeeling,
E-mail : rohan.rao1313@gmail.com

Monday, July 15, 2013

STH Stormwatch (15Jul2013) - Reporting a low pressure area in the Bay of Bengal

How are low pressure systems classified in India? What are the differences between low, depression and cyclone?

A low pressure system over Indian region is classified based on the maximum sustained winds speed associated with the system and the pressure deficit/ number of closed isobars associated with the system. The pressure criteria is used, when the system is over land and wind criteria is used, when the system is over the sea. The system is called as low if there is one closed isobar in the interval of 2 hPa. It is called depression, if there are two closed isobars, a deep depression, if there are three closed isobars and cyclonic storm if there are four or more closed isobars.
Considering wind criteria, the system with wind speed of 31 -50 kmph is called as depression and the low pressure system with maximum sustained 3 minutes surface winds between 51–59 kmph is called a deep depression. The system with maximum sustained 3 minutes surface winds of 63 knots or more is called as cyclonic storm
Associated wind speed
Low pressure area
Deep Depression
Cyclonic Storm
Severe Cyclonic Storm (SCS)
Very Severe Cyclonic Storm
Super Cyclonic Storm
Excess of 220

Praful Rao,
Dist Darjeeling

STH ACTIVITIES : Awareness camp in rural areas - Basilakha, East Sikkim - 13 July 2013

On 13 July 2013, STH was in Basilakha Bustee ( N 27°15.508’ /  E 088°34.969’) East Sikkim, as part of the Disaster Management / Tree Plantation program organised by Amdogolai C.D.C ( Child Development Center). There were 70-75 people in attendance mostly women and children.Among the many topics related to landslides and extreme weather that were covered, STH spoke about the importance of community capacity building both as a preventive as well as a responsive measure against landslides. 

We'd like to thank Amdogolai C.D.C and the members of Compassion International, who were involved in organizing this camp.

Rohan Rao,

Thursday, July 11, 2013

STH Stormwatch (11 July2013) : Reporting a low pressure build up in the Bay of Bengal

 "The low pressure  area over Odisha &adjoining northwest Bay of Bengal and its 
associated cyclonic circulation extending upto mid­tropospheric level tilting southwards 
with height persists. "
(Source : IMD Website)

 A low pressure area has formed in the Bay of Bengal and is now over Odisha and the adjoining North West Bay of Bengal, we will be tracking its movements over the next few days and updates will be posted on this blog.

Rohan Rao,
Dist - Darjeeling,
Email - rohan.rao1313@gmail.com

Tuesday, July 9, 2013

Watching the weather on the WWW

Having keenly followed the weather and reported the development and tracks of storms using broadband internet for the past 3yrs (as a part of "STH StormWatch" series, see here, here and here), I can confidently say that today, broadband internet places at the hands of ordinary people an extraordinary tool for checking and understanding  what was earlier the exclusive realm of scientists and meteorologists.
Placed below is how I, an untrained layman (with the help of a few very experienced
meteorologist friends) watch the weather (in my region) :-
a) I start off here which is a new page for Severe Weather warnings which IMetD has inserted into their home page.

b) I then have a look at this page :-

The 'Main Features' page (below) you gives a wealth of information, inclusive of ACTUAL weather which has occurred all over the country and a meteorological analysis. The latter is important because it tells you what is brewing up and where. The page further will give you more details on weather warnings.

c) Next I usually visit the satellite imagery and check out the Kalpana-1 INFRA RED (IR) channel (below)
IR images provide information about the temperature of the clouds. The coldest (therefore the tallest) clouds such as cirrus, cumulonimbus appear white whereas the warmer clouds will appear grey. Though the images are updated every 30mins, processing them takes a little time so the latest images that you see are around 1hr old.
and the visible channel
d) You can get a fairly good idea on the movement of clouds for the past 3hrs from the GIF animations by IMetD here
e) For more specific information on the weather in your region you may like to go to the IMetD Regional Meteorological Centre websites:-
f) Low pressure areas, depressions and cyclones can be tracked at the IMetD site here but I often get updates from
i. US Navy's Joint Typhoon Warning Centre also see here

ii. Pakistan Meteorological Department, IR imagery
Usually, IR images from this site are more current than those from IMD.
iii. Bangladesh Meteorological Department
iv. TRMM
f) Actual rainfall figures are available on an hourly basis from IMD's automatic weather station (AWS) here or from their automatic rainfall gauge stations (ARG) here.

Praful Rao
Dist Darjeeling

Sunday, July 7, 2013

Uttarakhand Cloudburst Jun2013

Uttarakhand Cloud Burst

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Technical advice from Dr B Nandi
About Dr B Nandi :

Dr Nandi is a renowned Aviation Meteorologist in India. He has served Indian Air Force for 33 years in various capacities. He is the founder Director of Centre for Numerical Weather Prediction for Air Force. He is an Alumni of Ramakrishna Mission Vidyapith, Purulia; Ramakrishna Mission College Narendrapur, Kolkata University; Burdwan University and Centre for Atmospheric Science, IIT, Delhi. Currently engaged as Chief  Meteorologist for Indigo Airlines for last 7 years.

Praful Rao,
Dist Darjeeling

Saturday, July 6, 2013

STH ACTIVITIES : Awareness campaign in Turuk, Sikkim - 04 July 2013

STH has always made an effort to educate the youth, about the hazards of landslides and extreme weather events in the Sub Himalayan region.
On 04 July 2013 STH conducted an awareness camp in Turuk bustee (village) in South Sikkim. There were around 85 people in attendance, most of them  students. STH talked about the recent events in Uttarakhand, cloud burst and a real danger of such an event occuring in this region along with the prevention and mitigation aspects of landslides.
Special thanks to Pastor Mathais Subba of Hyssop Ministries for organizing this camp.

Rohan Rao,
Dist Darjeeling.

Wednesday, July 3, 2013

Rainfall data Darjeeling district and N Sikkim - Jun2013

Jun2013 was extraordinary; it was the month of the "Himalayan Tsunami" when torrential rains over Uttarakhand and Himachal Pradesh in mid Jun2013, caused unprecedented loss of life and a disaster which the country is still trying to grapple with.
Whilst the rest of the country reported normal to excess rainfall, the north eastern states of India went deficient in rainfall. STH reported the formation of two low pressure areas in the Bay of Bengal, the first weather system eventually reaching the Uttarakhand region in mid Jun2013.
Also, two interesting facts observed in Jun2013 were :-

  • The 24hr rainfall over Dehradun on 17Jun2013 (338mm) was more than the entire month's rainfall in Kalimpong for Jun2013.
  • In the Darjeeling -Sikkim area, approximately half the month of June2013 was almost dry (less than 5mm rainfall).

    Praful Rao,
    Dist Darjeeling.