THE flood tragedy in Jammu & Kashmir resembles last year’s Uttarakhand disaster in many respects, particularly from a meteorological perspective (see “Why Kedarnath happened”; Frontline , July 26, 2013). The lessons to be learnt from the two disasters are also quite similar.
The primary cause in Jammu & Kashmir was the unexpected and incessant heavy rainfall for about three and a half days, beginning on September 3. The meteorological cause was almost exactly like the one that precipitated the disaster at Uttarakhand. The only difference is that last year the rainfall occurred, very unusually, in June, well before the south-west monsoon was expected to arrive in the north and north-western parts of the country.
Snowmelt and colliding wind systems As had happened in Uttarakhand, snowmelt may have significantly contributed to the floods in Kashmir. “High snowmelt runoff from the extensive snowpacks was observed in the mountainous regions this year,” wrote Shakil M. Romshoo, Head of the Department of Earth Sciences at Kashmir University, in an article on the website www.greaterkashmir.com. According to him, since 2010, there has been good snowfall in the Kashmir Himalayas, which is responsible for higher snow and glacier melt even in September.
In its August 29 weekly press release on the monsoon status, the India Meteorological Department (IMD), New Delhi, merely noted what would generally considered to be not an unusual phenomenon: “A western disturbance as an upper air cyclonic circulation lies over north Pakistan and adjoining Jammu & Kashmir extending up to mid-tropospheric level.” The weekly press release from the IMD, Pune, of September 3 gave more details of this westerly system and its movement: “The western disturbance...lay over north Pakistan and adjoining J&K on August 28 and 29, over J&K and neighbourhood on August 30 and 31. It moved away northeastwards on September 1.”
But the IMD, Pune, also noted the development of another western disturbance that followed it, which had moved from west Afghanistan and north Pakistan into adjoining Jammu & Kashmir and its neighbourhood on September 1. This system, the release said, had developed into a trough aloft over north Pakistan and Jammu & Kashmir on September 2 that moved over the State and its neighbourhood on September 3. This was exactly when there was a revival of the monsoon over much of the Indian subcontinent with increased rainfall activity in many parts of north-west India, including Jammu & Kashmir, where rainfall during the week ending September 3 was in excess by 55 per cent. The three-and-a-half day spell of persistent heavy rainfall over Jammu & Kashmir also began on September 3.
In Uttarakhand, a system of strong westerly winds from the Arabian Sea, which had become active over Pakistan in mid-June, moved over into north-west India. It was the interaction between an upper air westerly trough running from north-west Rajasthan to the east and the well-formed low-pressure system of the south-west monsoon from east to west that resulted in the heavy rainfall over Uttarakhand. In this case, too, the extensive rainfall in the adjoining regions of Pakistan suggests that there was also an Arabian Sea component to the westerlies. It is the Arabian Sea moisture that would have contributed to the concurrent rainfall over Pakistan.
So, around September 2-3, there was a westerly system moving from over Pakistan and a south-west monsoon system that was already active over the north-west regions. It is once again the meeting of these two weather systems that seems to have been the cause of heavy rainfall—the only difference is that this time it happened in September rather than during June-July-August (JJA), and predominantly over Jammu & Kashmir. The week ending September 10 saw rainfall in excess over the weekly normal by as much as 792 per cent and the very next week, ending September 17, the rainfall was in deficit by 96 per cent. Of course, these percentage variations may seem large. But, given that the monsoon rainfall over Jammu & Kashmir is not much, and the average seasonal rainfall for the State is only about 500-odd mm, a 100 per cent deficit, for example, does not mean much. It is less than in Haryana, Punjab or East Rajasthan. But a 792 per cent excess is significant. Some districts had a huge excess over their respective normals during September 3-10. In fact, many of the districts had significant excess rainfall during the latter half of the previous week itself (See table).
Inadequate predictions However, unlike in the Uttarakhand case, the national-level forecasts, which are made over a seven-day period with a Global Forecasting System (GFS), did not seem to have quite captured the strength of this interacting system and the intensity of the resulting precipitation over Jammu & Kashmir. The IMD, New Delhi, on August 29 said in its release: “Northwest India [which includes Jammu & Kashmir] is likely to receive scattered rainfall [meaning, in a few places] with the possibility of increase in spatial distribution in the second half of the week.”
By September 5, Jammu & Kashmir had already had two days of heavy rainfall. The September 5 release noted in retrospect: “During the week, two western disturbances affected northwest India, particularly Jammu & Kashmir, where heavy to very heavy rains have occurred towards end of week due the interaction with monsoon systems.” It, did, however, correctly predict that there would be “widespread” (in most places) and “fairly widespread”’ (in many places) rain with heavy fall (64.5-124.4 mm) in Jammu & Kashmir on September 5 and 6 respectively. Significantly, it did not say “heavy to very heavy” (124.5-244.5 mm) or “extremely heavy” (>244.5 mm). But districts like Anantnag (309.1 mm), Baramula (255.9 mm), Doda (320.8 mm), Jammu (354.2 mm), Kulgam (460.2), Pulwama (242.7 mm), Ramaban (425.6 mm), Reasi (556.0 mm), Sopian (348.0 mm) and Udhampur (605.5 mm) did receive “extremely heavy” rainfall. With the westerly system predicted to move eastwards and northeastwards after 48 hrs, rainfall beyond September 7 was, however, correctly forecast to be “scattered” or “isolated”.
Besides the weekly summary and forecast, the IMD also issues daily weather bulletins and weather warnings twice a day. It is not known what kind of three-day forecasts, which are made using a Weather Research and Forecasting (WRF) model, and warnings were issued because these are no longer on the IMD website. Also, according to B.P. Yadav, Head, National Weather Forecasting Centre, New Delhi, the IMD does not have an archiving system for these even as hard copies. That seems really strange.
But one must remember that the prediction of extreme events using models does have this kind of uncertainty. Therefore, supplementing information on the ground with forecasts becomes critical for adequate preparedness. “All-India bulletins are different. They are much coarser. They are for guidance only,” pointed out L.S. Rathore, the IMD director-general. “Field level warnings are issued only by Srinagar. He [the person manning the local office] is the guy on the field and responsible, and who liaises with the State government. But the IMD office there is submerged. When that office resumes he will prepare a report,” he said.
According to him, the Srinagar IMD office did issue a warning on September 2 about the impending heavy rainfall until September 6, on the basis of the forecast and ground situation in the State. The IMD head in Srinagar also apparently had a videoconference on September 3 with all the key State officials, right down from the Chief Relief Commissioner. Apparently, the Srinagar office is still non-functional owing to lack of electricity, and communication with Delhi has not been revived.
Need for collaboration When asked why there is not yet a good understanding of such interacting systems, he said: “Whenever there is an interaction, it creates a front. Air from the north-west would be cold and dry and the continental air mass would be humid and warm. And, therefore, at the front one [system] overrides the other. This results in a sharp increase in the instability in the frontal zone. And, if it is a mountainous terrain like J&K or Uttarakhand or Himachal, because of the orography, the instability is accentuated. So, from the prognosis point of view, you need to determine two things. One, where exactly are these air masses meeting; when exactly the two will meet; and, how long this meeting will persist. So these are the broad aspects that we need to capture correctly. Fortunately, most of the time this dynamics is better organised and we are able to capture the broader components of these. Second, how orography is treating the system over a vast domain. It is quite possible that certain orographic features help this process accentuate at a much higher scale than postulated. And at those locations the rate of precipitation is much higher compared with the rest of the region. Now that is a challenge. And it will be a challenge whenever such a system develops.”
Clearly, there is a need to undertake a systematic collaboration between institutions to understand such interacting systems on a much finer scale and develop models that can capture these features and predict more accurately. “Understanding a phenomenon is a much complex and heavyweight statement,” Rathore said. “We have some understanding. That’s what meteorology is all about. So modelling is secondary. First we need data. Down the chain we need to set up a good observing network. And that’s what we are doing. After Uttarakhand, only in August we have got our scheme approved for mountain meteorology wherein we will have a good number of instrumentation including radars, microwave radars, compact radars, automatic weather stations (AWRs), and automatic rain gauges (ARGs) and set up a much denser observing network. That is the first step.”
If, as remarked earlier, there are regions in the country that get far greater rainfall than Jammu & Kashmir did during the monsoon, what caused the extensive flooding? It has lasted for weeks, particularly in and around Srinagar city, and there are no signs of the waters receding quickly.
“The natural drainage in a mountainous terrain is such that wherever rain occurs it will come to the valley and discharge through the riverine path,” points out Rathore. “So all the water has to flow through the Rabi, Chenab and Jhelum rivers. How big are the catchments? What are the carrying capacities of these? Tawi, which flows through Jammu, was in spate with just two days of rain. Srinagar is a city made in the bed of a lake. This is a lake bed. Why do you allow such settlements there? There is no drainage to allow for river overflow. There is a return period for such meteorological extremes. This has to happen once in 100 years. Rest is all statistics. So what is new?”
Indeed, there have been heavy floods in the past on the Jhelum, in 1928 and 1959.
As Shakil M. Romshoo has observed in his article: “Though the meteorological (cumulative rainfall) and hydrological conditions (peak discharge) of the three extreme flood events might not differ significantly in magnitude (extremes) but the extent and the consequences of the socio-economic destruction of the 2014 floods qualifies it to be designated as the extreme of the extreme floods in the archived history of Kashmir.” The topography of the region makes it prone to flooding, but it is the loss of drainage and flood plains (flatlands along rivers) due to extensive land-use change that has resulted in this year’s disaster. The frequency of flooding has increased in the Valley in the past five or six decades, Romshoo noted.
Loss of waterbodies That the unregulated settlements and unplanned urbanisation in the Valley could lead to a major natural calamity in the event of flooding has been highlighted by many studies in the recent past. In a paper in 2008, Humayun Rashid and Gowhar Naseem of the GIS Laboratory, J&K State Remote Sensing Centre, Srinagar, wrote: “Srinagar city, a century earlier, had a unique ecological set-up with extensive areas under wetlands, lakes and water channels. Though siltation brought about in the lakes and wetlands, especially during floods, was but natural, yet subsequent encroachment, earth filling, planting and construction by individuals and converting water channels into roads, presents a living example of how these valuable assets of natural landscape of Srinagar were destroyed.” Loss of water bodies caused by undesirable land-use change, particularly deforestation, has resulted in microclimatic change of the city, they point out. “The Mar Nalla was lost to a road. Doodganga Nalla was converted into buildings. Bemina and Batmallo wetlands were converted into residential colonies,” they wrote.
Their study is based on Geographical Information System (GIS) studies that compared an archived topographical map of 1911 and a 2004 map generated from Indian Remote Sensing Satellite (IRS-1D) data of a total area of 69,677 hectares in and around Srinagar city. The comparison shows that a network of lakes and wetlands had characterised the region in the early 20th century. But there has been a significant reduction in the open water surface and wetland/marshy areas. Nearly 9119.92 ha of open water surface and wetlands has been lost to other land uses, a loss of over 50 per cent of what was there earlier. Population growth and siltation brought about by wanton deforestation in the catchment areas are important factors that have contributed to this land-use change, they concluded.
The impact of this has resulted in major problems relating to drainage since these wetlands and lakes used to act as sponges during floods, they pointed out. “Over the years,” they said, “it has been observed that with a continuous rain for 2-3 days in Kashmir valley, the city is threatened with floods in river Jhelum, while nothing would happen with this much of precipitation 2-3 decades back. Further, it has also been observed during the last decade that residential areas which never had floods in the past are getting inundated during floods in river Jhelum.” Such timely, and prophetic, observations by many—for example, a study by Shahab Fazal and Arshad Amin of Aligarh Muslim University in 2011—seem to have gone unheeded by State-level planners and the administration.
Apart from the differences in the scale of losses to property and life, the floods this time lasted longer than those in 1928 and 1959, and the high water levels have persisted for more than a week, noted Romshoo in his website essay: “The single most important reason for the high magnitude of the 2014 floods could be attributed to the loss of flood plains along the Jhelum.”
At present, only the Central Water Commission (CWC) has a Flood Forecasting cell, which provides flood forecasts in different parts of the country on the basis of in situ measurements of flow and water level characteristics at different sites combined with weather forecast inputs from the IMD. According to Vishnu Deo Roy, Director, Flood Forecasting, the CWC gives two types of forecasts, “level forecast” and “inflow forecast”, an activity that began in 1958. The level forecasts are basically information about the likely water level in the rivers in 12, 14, 16 and 18 hours in advance. The forecast is issued to the concerned authorities only when the water level at the forecast site is above the “warning level”, which is generally 1 m below the “danger level”.
This downstream level forecast is based on actual observed water level data upstream, which is measured on an hourly basis during the monsoon, together with rain gauge data in case of significant rainfall in the upper reaches which eventually discharges into the riverine system, and inputs of rainfall forecast during rainy seasons. “But there is uncertainty in these rainfall forecasts,” Deo Roy noted. The level forecasts are made through statistical projections based on 10 years of river data, according to him. Inflow forecasts are meant only for maintaining river levels through proper discharges from dams, barrages, and so on. The CWC operates a network of 878 hydrological sites, data from which are used for issuing level forecast at 147 sites and inflow forecasts at 28 sites.
According to him, sites are chosen on the basis of requisitions received from respective State governments. Other factors that decide the location include availability of hydrological/meteorological observation sites upstream of the forecast station and the lead time (time taken by a flood wave to travel from the observation site to the forecast site), and the area’s flood history. After the sites are chosen, certain parameters have to be finalised, said Deo Roy. The “danger level”, for instance, is determined in consultation with the State government departments and local bodies involved in flood management. These parameters are reviewed on a regular basis by the State government.
“The forecasts issued by the CWC generally cater to the flood of general nature having sufficient warning time available,” he had written in response to an article by Himanshu Thakkar of the South Asia Network on Dams, Rivers and People (SANDRP). Thakkar’s article had highlighted the CWC’s apparent failure in forecasting the Uttarakhand floods. “The hilly regions experience flash floods on many occasions, which is very difficult to predict due to the fact that flood wave in these rivers travels at a very high speed due to steep slopes. The lead time in such a case is very less as compared to that required in a general flood forecast system,” Deo Roy wrote.
More pertinently, the CWC does not have a single forecasting site in Jammu & Kashmir though the State is prone to flooding, particularly the Jhelum valley where Srinagar city is located. According to Deo Roy, the State government has not complied with the required protocols. He said: “It is a complex issue but includes finalisation of parameters such as warning time and danger level.”
In the context of the current flood situation in the north-eastern region, while there are many flood forecasting sites in Assam, there is none in Meghalaya, just as in Jammu & Kashmir. Therefore, while you can find details of the warning level, danger level, highest flood level in recent history and the forecasted level as well as the trend over the next 18 hours for all the sites in Assam, there is no information about the flood situation in Meghalaya. Having been jolted out of its slumber, it appears that the Ministry of Water Resources is now getting its act together to set up forecasting sites in Jammu & Kashmir . Hopefully, it will do so in Meghalaya and the other States that do not have level forecasting sites. It is also pertinent to note here that the IMD does not have a flood forecasting system. According to J. Srinivasan of the Indian Institute of Science (IISc), an India-United States project in the 1980s envisaged the constitution of such a unit within the IMD, and some people were trained towards this. But nothing came of it. “There has to be a more coordinated effort by the CWC and the IMD, and perhaps other agencies, to make flood forecasts.
This should not be very difficult. Once you have a terrain model of a given region, with rainfall forecast you should be able to make reasonable flood forecast and estimate the extent of flooding,” he said.
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