Saturday, December 27, 2014

STH Stormwatch (27Dec2014) : Reporting a well marked low in south Bay of Bengal

The well marked low pressure is expected to intensify into a depression in the next 48hrs

Praful Rao,
Kalimpong,
Dist Darjeeling

Monday, November 17, 2014

STH seminar on 'Urban Planning and Disaster Risk Reduction' : 14Nov2014

                       
We would like to thank all those who travelled from distant shores and across rivers and valleys to attend our seminar - thanks to them the seminar went off wonderfully well.

Praful Rao,
Kalimpong,
Dist Darjeeling

Tuesday, November 11, 2014

Saturday, November 8, 2014

STH Stormwatch (08Nov2014) : Limitations of human knowledge, the depression fizzles out

Having almost, well, a jihadi belief in the predictions of meteorological science, it is scary to think their forecasts could also go wrong.
So it is good the storm weakened (and became a low pressure instead of blossoming into a full blown cyclone as predicted) but what if the forecast had gone awry and the depression had become a Very Severe Cyclone in a lesser time than forecast?
Scary!

Praful Rao,
Kalimpong,
Dist Darjeeling

Thursday, November 6, 2014

STH Stormwatch (06Nov2014 update) : The depression in the Bay of Bengal intensifies

‘The depression over central Bay of Bengal moved north-northwestwards during the past 6h, intensified into a deep depression and lay centred at 0830 IST on 06Nov2014 over central Bay of Bengal , 580km southeast of Vishakhapatnam. It would move northwestwards and intensify further into a Cyclonic storm during next
 24h. It would then move west ­northwest towards Andhra Pradesh coast. It would weaken gradually into a depression while reaching the coast on 08Nov2014, night.’

Praful Rao,
Kalimpong,
Dist Darjeeling


Wednesday, November 5, 2014

STH Stormwatch (05Nov2014 update): The low pressure intensifies into a depression


As per JTWC, 'the potential for the development of a significant tropical cyclone within the next 24hr is upgraded to medium'

Praful Rao,
Kalimpong,
Dist Darjeeling



Monday, November 3, 2014

From the newspapers : Signs in groundwater may help predict earthquakes six months in advance.




Excerpt from 'The Guardian' (21Sep2014) : 

Scientists searching for a way to predict earthquakes have uncovered the most promising lead yet, after uncovering tell-tale chemical spikes in groundwater up to six months before tremors struck.
Major earthquakes can kill hundreds of thousands of people, as in Haiti in 2010, but they are the only natural disaster that cannot currently be forecast. Some experts think a useful prediction of time, place and magnitude may be an impossible dream. Previously, scientists have examined radon gas leaks, heat maps and even unusual animal behaviour as possible earthquake indicators, without success.
But now geologists taking weekly measurements of groundwater chemistry in northern Iceland over five years have discovered big shifts four to six months before two separate earthquakes in 2012 and 2013. The quakes were both significant in size – over magnitude five – and 47 miles from the sampling site.
“This does not mean we can predict earthquakes yet, but at the least we have shown something happens before earthquakes,” said Prof Alasdair Skelton, at Stockholm University, Sweden, who led the research published in Nature Geoscience. “That is tantalizing, as it means something is happening to the rocks before the earthquakes. We are highlighting groundwater chemistry as a promising target for future earthquake prediction studies.”
The fact the chemical spikes were identified before two different earthquakes is significant, said Skelton, because it indicates they are not a mere coincidence. He said the chances of that were a hundred-thousand to one. The previous best evidence for groundwater changes was an analysis of Japanese spring water bottled before and after the huge 1995 Kobe earthquake, which killed 6,400 people. The Kobe water also revealed a chemical spike, but there was too little data to make a link to the tremor statistically convincing. The chemical changes are thought to occur as stress builds on the rocks before the earthquakes and creates small fractures which connect up different acquifers allowing them to mix.
Skelton said the next steps are to understand better exactly how the chemical spikes occur and then to see if these can be observed in other parts of the world. The rock in Iceland is of only one type, basalt, and it may be that in places where there is a mix of rock types the chemical changes will be even more marked, he said.
The new work was praised by other geologists. “The potential for predicting earthquakes has great importance, and great claims require strong evidence,” writes Steven Ingebritsen, at the US Geological Survey and Michael Manga, at University of California, Berkeley, in a commentary in Nature Geoscience. “The new observations are sufficiently compelling to prompt further investigation.”
Professor Ian Main, at the University of Edinburgh, Scotland, said caution was needed and the influence of other possible factors, such as shifting magma below the ground, needed to be assessed. “There is a long way to go before observations such as these could be turned into operational tools for forecasting earthquake probabilities,” he said. “Most geophysical and geochemical signals fluctuate all the time, so it is virtually inevitable that some areas will have signals coincident with earthquakes.” The proof will be in making a successful future prediction, he said: “[Otherwise], this process is a bit like going into the bookies after a race and claiming you would have bet on the winning horse.”
Main added: “Earthquake prediction, sufficiently reliable and accurate to justify an evacuation, has long been the ‘holy grail’ of seismology and it is likely to be difficult, if not impossible, to achieve.” There are strong theoretical reasons why earthquakes may be inherently unpredictable, because large tremors can set off by relatively tiny – and therefore hard to distinguish – stresses in the rocks. But these reasons do not rule out the possibility that some reliable precursor signals may be found.
“In terms of what the public would understand by an earthquake prediction, the jury is still out,” Main said.

Praful Rao,
Kalimpong,
Dist Darjeeling

Sunday, November 2, 2014

Rainfall data Oct2014 : Darjeeling- Sikkim Himalaya

As can be seen from the above map, the Darjeeling-Sikkim Himalaya is running 80% deficient in rainfall, the data for 3 stations is as follows :-
a. Kalimpong - 20mm (on 15Oct - a spillover from Cyclone 'HudHud'.)
b. Mangan (N Sikkim ) - 27mm
c. Darjeeling - 33mm

Monthly rainfall normal for the month of Oct in the Darjeeling-Sikkim Himalaya as per IMetD  is 154.2mm (see here).
No rain, means no landslides but that also means less potable water and more forest fires during the many dry months ahead.

Praful Rao,
Kalimpong,
Dist Darjeeling

Saturday, November 1, 2014

Upcoming event, 14Nov2014 : Seminar on 'Urban planning and DRR' at Kalimpong

Kindly intimate us if you intend to attend the seminar and sorry, we do not have accommodation/transportation arrangements for the same.

Praful Rao,
Kalimpong,
Dist Darjeeling.

Friday, October 31, 2014

STH stormwatch : Death of a cyclone (31Oct2014)


The top IR images placed clearly shows the death of 'Cyclone Nilofar'.
As per IMetD, the depression shown on the image on the right is expected to 'move northeastwards and weaken into a well marked low over the northeast Arabian sea off north Gujarat coast during the next 12 hrs'.
JTWC also has issued its final warning for the cyclone (below)

Which brings into question what about predicted landfall on 01Nov2014?

Praful Rao,
Kalimpong,
Dist Darjeeling

Tuesday, October 28, 2014

STH Stormwatch(28Oct2014) : Updated track and timeline of Very Severe Cyclone 'Nilofar'


'Nilofar' has now been upgraded to a 'Very Severe Cyclone' and has 'moved north- northwestwards in the past 6hrs'.
Landfall is expected on 01Nov2014 between north Gujarat and adjoining Pakistan coast (around Naliya).

Praful Rao,
Kalimpong,
Dist Darjeeling

Sunday, October 26, 2014

STH Stormwatch (26Oct2014) : Cyclone 'Nilofar' is born in the Arabian sea.

Excerpt from IMetD (All India Weather Bulletin)
'The deep depression over westcentral & adjoining southwest Arabian sea moved slightly northwestwards, intensified into a Cyclonic Storm, "NILOFAR" at 1130 hours IST and lay centered at 1430 hours IST of today, 26thOctober, 2014 near lat.14.1°N and long. 62.0°E, about 1270 km west-southwest of Mumbai and 910 km east south east of Salalah (Oman). It would move initially north-northwestwards during next 48 hours and then recurve northeastwards towards north Gujarat and adjoining Pakistan coast during subsequent 72 hours.
It would intensify further into a severe cyclonic storm during next 24hours'
The forecast tracks shown above are from JTWC.

STH will continue monitoring this storm and will post salient updates from time to time, however we will not be posting detailed tracks and movements as we do for storms in the Bay of Bengal which impact the Darjeeling-Himalaya directly.

Praful Rao,
Kalimpong,
Dist Darjeeling

Saturday, October 25, 2014

STH Stormwatch : Cyclone formation alert in the Arabian sea


IMetD is reporting a well-marked low pressure (see IR image on top of 6.30am today) in the south eastcentral Arabian sea, which is likely to intensify into a cyclone in the next 48h.
JTWC tracks are shown below.
It is amazing that a storm brewing so far away can spew clouding which is affecting us today - as I write it is turning cloudy in the Darjeeling-Sikkim Himalaya (see cloud trail in the IR image on top)

Praful Rao,
Kalimpong,
Dist Darjeeling

Friday, October 17, 2014

STH activities : Mapping rainfall in the Darjeeling-Sikkim Himalaya

Since most landslides in our region are rain induced, it is vital to obtain and record rainfall data. STH has been acutely aware of this and rainfall data from 2009 for some of the major towns are available in this blog.
In this regard, what we found is that there is actually no shortage of rainfall gauges with most tea gardens having some sort of meteorological observatory and many government departments also maintaining precipitation records - however, gaining access to this data is a labyrinthine process, full of bureaucratic red tape (applications in writing, payment for rainfall data etc).
In this connection, many of IMetD's superb AWS stations are sadly not maintained and as such either give erroneous data or no data (and no amount of complaining to concerned authorities seems to set things right!)
To obviate this STH (along with a few NGOs) has decided to set up our own network of rainfall gauges in Darjeeling district and in Sikkim. Over the past 3 months we have procured 17 manual (Symon's type) rainfall gauges which will be positioned at various locations in this region. In addition, STH already has 3 automatic rainfall gauges available Darjeeling, Mangan (North Sikkim) and Kalimpong.
Therefore, for the monsoons of 2015 we will have rainfall data from 20 stations in the Darjeeling - Sikkim Himalaya displayed on this blog - it will be available for free and without any red tape.

Praful Rao,
Kalimpong,
Dist Darjeeling

Sunday, October 12, 2014

STH Stormwatch (12Oct2014) : Very Severe Cyclone 'Hudhud' makes landfall

As I write, the eye of the storm has just crossed Vishakapatnam and fortunately not much damage has been done (tho 2 rain related deaths are being reported) - however, as in the previous cyclones which have hit this area, the flooding and devastation often takes place AFTER the cyclone/depression has moved inland releasing huge amounts of precipitation.
Thus, the worse may be yet to come.

Praful Rao,
Kalimpong,
Dist Darjeeling

Saturday, October 11, 2014

STH stormwatch: Slideshow of Very Severe Cyclone 'Hudhud' in the Bay of Bengal (07Oct2014 till date)


Almost exactly to the day, a year after Very Severe Cyclone Phaillin
(07Oct-15Oct2013) battered the eastern coast of India, and as if resurrecting its ghost Very Severe Cyclone ‘Hudhud’ will be making landfall around Vishakapatnam tomorrow, exactly on the same date that Phaillin did so one year ago.
STH as a part of its stormwatch series maintains, a close watch on the weather activity in the Bay of Bengal and has tracked and plotted all major weather events in the Bay and elsewhere (Uttarakhand cloudburst) over the past few years.
All are recorded on this blog.
STH first reported the formation of a low pressure in the Bay of Bengal on 07Oct2014 and has thereafter maintained a close watch on the development of the cyclone which, today is the full blown 'Very Severe Cyclone Hudhud' which is breathing fire, off the coast of Andhra Pradesh.
This slide show (which is being updated on a daily basis), shows the formation and movement of the weather system from 07Oct2014 and offers other related information.

Praful Rao,
Kalimpong,
Dist Darjeeling

STH Stormwatch (11Oct2014) : The Eye of the Storm, Very Severe Cyclone 'Hudhud'

For the first time since 07Oct2014, when 'Hudhud' appeared as a low pressure area near the Andaman Islands, the eye of the storm is clearly visible now, in the IR images.
Updated tracks and information on Very Severe Cyclone 'Hudhud' will be posted here from time to time

Praful Rao,
Kalimpong,
Dist Darjeeling

Friday, October 10, 2014

Wednesday, October 8, 2014

STH Stormwatch (08Oct2014) : Cyclone 'Hud Hud' forms in the Bay of Bengal


The depression in the Bay of Bengal has been upgraded to a cyclone named 'Hud Hud' or TC03B (JTWC).
'Hud Hud' would intensify in a very severe cyclonic storm and proceed along the track forecast .

Praful Rao,
Kalimpong,
Dist Darjeeling

Tuesday, October 7, 2014

STH Stormwatch : Update on depression in Bay of Bengal


  • IMetD has upgraded the well-marked low pressure into a depression which would further intensify into a deep-depression within 24h and eventually become a cyclone.
  • The JTWC predicted tracks are shown on top.
  • The latest IR photo is shown above.
Praful Rao,
Kalimpong,
Dist Darjeeling

STH Stormwatch 07Oct2014 : the first cyclone in Bay of Bengal of 2014?

Excerpt from IMetD
'The well marked low pressure area over north Andaman sea and neighborhood has concentrated into a Depression and lay centred at 0830 hours IST of today, near lat.11.5°N / long 95.0° E, about 250 km east of Port Blair.
It would move in a west­ northwesterly direction and intensify into a deep depression within 24 hours and further intensify into a cyclonic storm thereafter.'


Updates and tracks of the storm will be posted as required.

Praful Rao,
Kalimpong,
Dist Darjeeling.

September 2014 : Rainfall data of Darjeeling and Sikkim and extreme weather events in Kashmir and Assam

In Sept 2014, rainfall in SHWB and Sikkim went deficient again with no major weather system ie depression or cyclone forming in the Bay of Bengal during the month. Consequently there was no major landslide in the area.
Things were very different in Kashmir during the first of the Sept where approx 3000% excess rainfall was recorded at places (see red dots in middle chart), this lead to flooding and landslides on a hitherto unseen scale in the Kashmir valley.
Towards the end of the month, we saw a repeat of this situation in Assam and Meghalaya and excess rainfall exceeding 1500% of normal was seen in some parts of Meghalaya (see red dots in bottom chart)

Praful Rao,
Kalimpong,
Dist Darjeeling