Posts Tagged ‘water’
In this panel of maps the relationship between the district of Parbhani (in the Marathwada region of Maharashtra) and water is graphically depicted over time. The blue squares are water bodies, as seen by a satellite equipped to do so. The intensity of the blue colour denotes how much water is standing in that coloured square by volume – the deeper the blue, the more the water.
Water bodies consist of all surface water bodies and these are: reservoirs, irrigation tanks, lakes, ponds, and rivers or streams. There will be variation in the spatial dimensions of these water bodies depending on how much rainfall the district has recorded, and how the collected water has been used during the season and year. In addition to these surface water bodies, there are other areas representing water surface that may appear, such as due to flood inundations, depressions in flood plains, standing water in rice crop areas during transplantation stages. Other than medium and large reservoirs, these water features are treated as seasonal and some may exist for only a few weeks.
The importance of monitoring water collection and use at this scale can be illustrated through a very brief outline of Parbhani. The district has 830 inhabited villages distributed through nine tehsils that together occupy 6,214 square kilometres, eight towns, 359,784 households in which a population of 1.83 million live (1.26 rural and 0.56 million urban). This population includes 317,000 agricultural labourers and 295,000 cultivators – thus water use and rainfall is of very great importance for this district, and indeed for the many like it all over India.
This water bodies map for Parbhani district is composed of 18 panels that are identical spatially – that is, centred on the district – and display the chronological progression of water accumulation or withdrawal. Each panel is a 15-day period, and the series of mapped fortnights begins on 1 January 2015.
The panels tell us that there are periods before the typical monsoon season (1 June to 30 September) when the accumulation of water in surface water bodies has been more than those 15-day periods found during the monsoon season. See in particular the first and second fortnights of March, and the first fortnight of April. [Here is a good quality image of the census map, 968KB.]
During the monsoon months, it is only the two fortnights of June in which the accumulation of water in the surface water bodies of Parbhani district can be seen. The first half of July and the second half of August in particular have been recorded as relatively dry.
This small demonstration of the value of such information, provided at no cost and placed in the public domain, is based on the programme ‘Satellite derived Information on Water Bodies Area (WBA) and Water Bodies Fraction (WBF)’ which is provided by the National Remote Sensing Centre (NRSC), Indian Space Research Organisation (ISRO), Department of Space, Government of India.
For any of our districts, such continuous monitoring is an invaluable aid to: facilitate the study of water surface dynamics in river basins and watersheds; analyse the relationships between regional rainfall scenarios and the collection and utilisation of water in major, medium reservoirs and irrigation tanks and ponds; inventory, map and administer the use of surface water area at frequent intervals, especially during the crop calendar applicable to district and agro-ecological zones. [Also posted on India Climate Portal.]
With two weeks of the June to September monsoon remaining in 2015, one of the end-of-season conclusions that the India Meteorological Department (IMD) has spoken of is that four out of ten districts in the country has had less rainfall than normal.
This overview is by itself alarming, but does not aid state governments and especially line ministries plan for coming months, particularly for agriculture and cultivation needs, water use, the mobilisation of resources for contingency measures, and to review the short- and medium-term objectives of development programmes. [See ‘A method for a post-carbon monsoon’ for a recent discussion.]
The detailed tabulation (done for 15 weeks) is meant to provide guidance of where this may be done immediately – in the next two to four weeks – and how this can be done in future. The districts are chosen on the basis of the size of their rural populations (calculated for 2015). Thus Purba Champaran in Bihar, Bhiwani in Haryana, Rewa in Madhya Pradesh and Viluppuram in Tamil Nadu are the districts in those states with the largest rural populations.
In this way, the effect of rainfall variability, from Week 1 (which ended on 3 June) to Week 15 (which ended on 9 September), in the districts with the largest rural populations can be analysed. Because a large rural population is also a large agricultural population, the overall seasonal impact on that district’s agricultural output can also be inferred.
The distribution of the districts is: six from Uttar Pradesh; five each from Andhra Pradesh, Bihar, Chhattisgarh, Gujarat, Haryana, Jharkhand, Karnataka, Maharashtra, Madhya Pradesh, Odisha, Punjab, Rajasthan, Tamil Nadu and West Bengal; four each from Assam, Jammu and Kashmir, and Kerala; three from Uttarakhand; two from Himachal Pradesh; one each from Arunachal Pradesh, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura.
Using the new 11-grade rainfall categorisation, a normal rainweek is one in which the rainfall is between +10% more and -10% less for that week. The overview for this group of 100 districts, only 11 have had five or more normal weeks of rain out of 15 weeks. In alarming contrast, there are 77 districts which have had three or fewer normal weeks of rain – that is, more than three-fourths of these most populous districts. Half the number (51 districts) have had two, one or no normal weeks of rain. And 22 of these districts have had only one or no normal weeks of rain.
From this group of 100 most populous (rural population) districts Gorakhpur in Uttar Pradesh and Nagaon in Assam have had the most deficit rainweeks, tallying 13, out of the 15 tabulated so far. There are ten districts which have had 12 deficit rainweeks out of 15 and they are (in decreasing order of rural population): Muzaffarpur (Bihar), Pune and Jalgaon (Maharashtra), Surguja (Chhattisgarh), Panch Mahals and Vadodara (Gujarat), Firozpur (Punjab), Thiruvananthapuram (Kerala), Hoshiarpur (Punjab) and Mewat (Haryana).
The India Meteorological Department has just released it’s long-awaited forecast for the 2015 Indian monsoon. In terms of the quantity of rainfall over the duration of the monsoon season (June to September) the IMD has said it will be 93% of the ‘Long Period Average’. This average is based on the years 1951-2000.
What this means is the ‘national’ average rainfall over the monsoon season for India is considered to be 89 centimetres, or 890 millimetres. So, based on the conditions calculated till today, the ‘national’ average rainfall for the June to September monsoon season is likely to be 830 millimetres.
There are caveats and conditions. The first is that the 93% forecast is to be applied to the long period average for each of the 36 meteorological sub-divisions, and a ‘national average’ does not in fact have much meaning without considerable localisation. The second is that the forecasting methodology itself comes with a plus-minus caution. There is “a model error of ± 5%” is the IMD’s caution.
This first forecast and the model that the forecast percentage has emerged from are thanks to the efforts of the Earth System Science Organization (ESSO), under the Ministry of Earth Sciences (MoES), and the India Meteorological Department (IMD), which is the principal government agency in all matters relating to meteorology. This is what the IMD calls a first-stage forecast.
As with all complex models, this one comes with several considerations. The ESSO, through the Indian Institute of Tropical Meteorology (IITM, which is in Pune), also runs what it calls an ‘Experimental Coupled Dynamical Model Forecasting System’. According to this, the monsoon rainfall during the 2015 monsoon season (June to September) averaged over India “is likely to be 91% ±5% of long period model average”. (The IMD forecast is available here, and in Hindi here.)
This is a lower figure than the 93% headline issued by the IMD. This too should be read with care as there are five “category probability forecasts” that are calculated – deficient, below normal, normal, above normal and excess. Each is accompanied by a forecast probability and a climatological probability (see the table). The maximum forecast probability of 35% is for a below normal monsoon, while the maximum climatological probability is for a normal monsoon.
As before, time will tell and the IMD will issue its second long range forecast in June 2015. Our advice to the Ministry of Earth Sciences and to the IMD is to issue its second long range forecast a month from now, in May, and also to confirm these forecasts two months hence in June, when monsoon 2015 will hopefully be active all over the peninsula. [This is also posted on India Climate Portal.]
From the first week of June 2014 until the middle of September 2014, there have been floods and conditions near drought in many districts, but for India the tale of monsoon 2014 comes from individual districts and not from a national ‘average’ or a ‘cumulative’.
This revealing chart tells some of that tale. It shows that for the first six weeks of monsoon 2014, most districts recorded rain below their normals for those weeks.
The lines are percentile lines; they tell us what percent of districts recorded how much rainfall in a monsoon week relative to their normals for that week. This chart does not show how much rain – it shows distance away from a weekly normal for districts.
The left scale is a percentage – higher percentages indicate how much above normal districts recorded their rainfall, negative numbers show us how much below normal their rainfall was.
The dates (the bottom scale) are for weeks ending on that date for which ‘normals’ and departures from normal were recorded. The P_01 to P_09 lines are the percentiles (10th to 90th) of districts in every week.
The district weekly normal is an important measure for matters like sowing of crop and issuing water rationing instructions in talukas and blocks. In the week ending 23 July for example, we see that the 60th percentile line spiked above normal, and this means that in that week only four out of ten districts all over India received the amount of rain it should have based on the average of the last 50 years.
The districts overview chart is distilled from the detailed weekly tables I have assembled (see the image of the Maharashtra table). For the whole country, what the districts tell us about the monsoon so far is a very much more detailed and insightful tale than the typical offering by the Meteorological Department (see India sub-divisional map). These weekly district tables are coded using my modified monsoon methodology, geared towards aiding decisions for local administrations especially for prolonged arid conditions leading to drought.
The biggest river deltas are flat and that’s why the cities which occupy some of the have expanded so much, so quickly. The last 50 years has seen a big population expansion on deltas – cities like Dhaka in Bangladesh. Twelve megacities on deltas have expanded in terms of populations from 62 million in 1975 to 153 million in 2010, an expansion that is not slowing.
‘Global Change’, which is the magazine of the International Geosphere Biosphere Programme (IGBP), has brought out a special number of deltas and the risks borne by city administrations that occupy deltas. The IGBP, in its own words, “coordinates international research on global-scale and regional-scale interactions between the Earth’s biological, chemical and physical processes, and their interactions with human systems”.
Flooding both from rivers and the sea is increasing. There was a storm surge in the Irrawaddy in Myanmar in 2008 when 200,000 people were killed. But people are still living on the delta. However, the estimate is that two million people have left the Indus delta in Pakistan to move to higher ground as salt water has invaded the farming zone. [A larger version of the graphic above can be found here (1.4MB). The original IGBP infographic which I have modified can be found here – caution, big file (12.7MB)].
The Po delta (near Venice in Italy) subsided largely because methane was being pumped from underground. They stopped the pumping and the delta is sinking 10 times less fast than it was. But the land surface is not actually rising, and it’s still below sea level. The Chao Phraya River Delta (along which Bangkok is built) subsided because of groundwater being pumped out to supply Thailand’s thirsty capital. So they introduced a tax on water use, such as showers. In Shanghai, the local government slowed the rate of pumping water out of the ground.
However, when countries set up commissions to look at the natural environment, it’s often water/river courses they’re concerned about, like with the Rhine. There is not so much focus on the delta. Where countries have tried geo-engineering, they can scarcely bear the prohibitive costs. It is estimated that China in the 15th to 18th centuries used 12-15% of its historical GDP in attempts to control the Yellow River from spilling out into its floodplain, but these gigantic efforts were never really successful.
Ignoring the torpor of the summer heat, the India Meteorological Department has dusted off the statutory paragraphs that give us in the sub-continent a first indication of what monsoon for the year may be like. The result this year, both scintillating pages, has been made that much more gripping by the inclusion of El Niño. The IMD’s treatment of the normal variables whose interplay determine the nature of any monsoon is perfunctory – which is surprising as the regional and international earth observation networks spare no detail and tend to inundate us with data and analysis.
But the IMD, especially for the south-west monsoon, has always preferred to be spartan. Perhaps there is some philosophical dictum that us non-meteorologists have yet to grasp, and if so then the only criticism we may be permitted, if the IMD had its way, its to ask for more such teaching. But the IMD does not have its way, and we publics whose monies support its work must continue to demand from the recalcitrant department better, much better, application and communication of its work.
The official release, ‘Long Range Forecast For the 2014 Southwest Monsoon Season Rainfall’, is delivered to us by the IMD, Ministry of Earth Sciences (MoES). There is the usual paragraph claiming a profundity of observation and of the IMD being a standard-bearer of superior method. “Operational models are critically reviewed regularly and further improved through inhouse research activities,” says the IMD. But what we still have, in a tradition that is probably three generations old, is the two stage forecast (one in April, the second in June). [Here is the release in Hindi.]
I think this proves how out of step the IMD – and the Ministry of Earth Sciences (grand title isn’t it?) – is with what citizens of India experience in their villages, towns, fields and hills. For, the south-west monsoon no longer arrives in the first week of June, and it no longer begins to depart by mid-September. Climate change began to alter that comfortable rhythm years ago, but the IMD’s forecasting grindstone is the same, never mind how many new earth observation satellites India pelts into orbit.
With all these provisos, stated and implicit, what has the IMD told us?
First, that the “experimental ensemble forecast based on IMD seasonal forecast model (SFM) indicates that the rainfall during the 2014 monsoon season (June to September) averaged over the country as a whole is likely to be 88% ± 5% of long period average (LPA)”. This means that in places it could be as low as 83% of the average, and no more than 92% of the average. Combine this with the assessments about the 2014 El Niño and we can see why, far from being satisfied that the IMD is considering both the monsoon and El Niño, we ought to monitor independently both and force the IMD to become more responsive.
Second, that “the experimental forecast based on the coupled dynamical model forecasting system suggest that the monsoon rainfall during the 2014 monsoon season (June to September) averaged over the country as a whole is likely to be 96% ± 5% of long period model average (LPMA)”. This is a more hopeful set, but also shows that the IMD, by telling us of two different scenarios from two models, is hedging its forecast, which is not what its job is.
Third, the IMD has said “the experimental five category probability forecasts for the 2014 monsoon season rainfall over the country as a whole using the experimental dynamical prediction system are 33% (deficient), 20% (below normal), 24% (normal), 6% (above normal) and 17% (excess)”. This means, using this ‘probability’, that a normal monsoon for 2014 has only a 1-in-4 chance whereas a deficient monsoon (that is, total rain less than 90% of the long period average) has a 1-in-3 chance.
This is a prognosis that stands between serious and grim, for a 10% drift towards the lower side of an expected average, for any of our 36 agro-meteorological regions, can spell ruin for farmers and severe hardship for water consumers. How have central and state governments prepared for such a forecast? We have no information, most likely because there has been no preparation (there are contingency plans for the chronically drought-prone districts, but these are normally triggered when there is an official declaration by the state government that there are conditions of drought in parts of the state). Elections or no elections, El Niño cares not, and it is up to the state governments to make preparations for a monsoon 2014 whose delivery of water already looks uncertain.
We have now one important basis to consider carefully the consequences of the macro-economics of GDP growth and all the programmes to encourage such ‘growth’.
In 2011, 65.49 million Indians lived in slums in our cities and towns (the number was 52 million when recorded in Census 2001). It is important not to allow the immensity of our population numbers (1,250 million now in 2013) to diminish this extraordinary and disgraceful number in any way.
The 65 million who live in slums are all together a population equivalent to the populations of Thailand or France or Britain. This is also larger than the populations of Italy or Burma, South Africa or South Korea.
In Census 2001 the total number of towns that reported slums was 1,743. In Census 2011 the total number of towns and cities that reported slums was 2,613 out of 4,041 ‘statutory’ towns and cities. Here is the guideline for classifying types of slum settlements from Census 2011:
1. All notified areas in a town or city notified as ‘slum’ by state, union territories’ administrations or local government under any act including a ‘slum act’ may be considered notified slums (22.5 million live in notified slums).
2. All areas recognised as ‘slum’ by state, union territories administration or local government, housing and slum boards, which may have not been formally notified as slum under any act may be considered as recognised slums (20.1 million live in recognised slums).
3. A compact area of at least 300 population or about 60-70 households of poorly built congested tenements, in unhygienic environment usually with inadequate infrastructure and lacking in proper sanitary and drinking water facilities. Such areas should be identified personally by the ‘charge officer’ and also inspected by an officer nominated by the Directorate of Census Operations. This fact must be duly recorded in the charge register. Such areas may be considered as identified slums (22.8 million live in identified slums).
[You can get the Primary Census Abstract for slum populations 2011 here as an xls file. There is a very informative presentation on the data available here as a pdf. Consult the primary pages on Census 2011 – India’s 2011 Census a population turning point, India’s 2011 Census the states and their prime numbers and The data vault of the 2011 Census.]
This is a three-minute film that narrates the impact of humans on the planet and on the water cycle. The global footprint of human habitation – built-up regions, water extraction, industrial agriculture, mineral and fossil fuel extraction – has driven Earth into a new geological epoch: the Anthropocene.
Human activities such as damming and agriculture are changing the global water cycle in significant ways. The film quickly and dramatically describes Earth’s changing global water cycle, why it is changing and what this means for the future. The vertical spikes that appear in the film represent the 48,000 large dams that have been built. The film is part of the first website on the concept of humans as a geological force and was made for the the International Geosphere-Biosphere Programme.
In just under six weeks from today, the water available per head in India from our major reservoirs will drop under the 100 litres per day mark. This will happen on or around 06 June 2013, give or take a day.
For India’s 59 cities with populations of over a million (this will be so in mid-2013, see ‘India in 2015 – 63 million-plus cities’) this will mean an ever more frantic and dangerous race to secure water stocks by urban water mafia, who plunder public water storage and groundwater aquifers alike.
In the largest of these cities, their water boards claim to supply between 160 and 200 litres per capita per day (lpcd). This amount is roughly in line with what residents in comparably large East and South-East Asian cities are supplied, and is well above the lower end (100 lpcd) offered by the World Health Organisation as the minimum ‘optimal’ daily water stock required by an individual to maintain health and hygiene (100-200 lpcd is the band).
That’s the WHO view, but even in the Tenth Five Year Plan (2002-07) it was recommended that in India’s largest metropolitan cities the minimum must be 150 lpcd and in large non-metro cities the minimum must be 135 lpcd.
But six weeks from now, judging by the rate at which water has been used in 2013 from the 84 major reservoirs, we are not going to have, per head per day, even 100 litres of water. (Also see ‘Big dams, scarce water, thirsty India, uncertain monsoon’.)
How did we get here, so quickly and so dry? On 14 February 2013, the total water stored in the 84 major reservoirs was 68.718 billion cubic metres (bcm). Over the next ten weeks, until 25 April 2013, that total has dropped steeply to 42.304 bcm.
The Central Water Commission monitors the levels of and volumes in these 84 reservoirs, which if they all were full would store 154.421 bcm. These 84 reservoirs, says the CWC, represent 61% of the country’s water stored in reservoirs, which is altogether 253.388 bcm.
Judging by the same rate of water drawal from these 84 reservoirs, we have used over 43 bcm from all reservoirs in ten weeks, depleting our reservoir stock from 112.6 bcm to 69.3 bcm. This also means that in early February 2013, each of us were (notionally) holding a water stock of about 247 litres per day, a stock that was shrinking at a rate of about 1.3 litres per day to reach 152 litres per day in late April. And remember this is notional water stock per head from reservoirs, water that is used for agriculture and industry too.
What will happen between now and 06 June, when that individual stock drops under 100 lpcd? The Indian Meteorological Department has claimed (the usual bland and bored claim, as if monsoon was just another filing cabinet) that we will have a normal monsoon. As usual, the IMD has made no effort to link water with our alarming depletion of litres per head per day (it does link monsoon with GDP though, typically correct politically, typically unconcerned about human, animal and ecosystem need).
And what if the monsoon is late, scanty or erratic, as has happened with every monsoon since 2009? The IMD doesn’t know, your city’s PWD and municipality don’t know. But the water mafia do, and they’re getting very busy.
Why did India’s Ministry of Water Resources not start rationing water use at the beginning of 2013? Data on the water levels of the 84 major reservoirs in the country (kept by the Central Water Commission) show an alarming rate of withdrawal over the period January to March 2013.
Over seven weeks, these reservoirs disgorged 20.525 billion cubic metres (BCM) of water – for industrial, commercial, residential and irrigation purposes. By 14 March 2013, the combined water stock in these 84 major reservoirs was 57.355 BCM – on 24 January 2013 that total had been 77.869 BCM. At this rate of water use, by 09 May 2013 – seven weeks hence – there will be a perilous 36.8 BCM in the major reservoirs, and with the possible first onset of the 2013 south-west monsoon still a month away.
The major reservoirs that have disgorged the most water during this period are: Srisailam (Andhra Pradesh) 2.353 bcm; Hirakud (Orissa) 1.808 bcm; Indira Sagar (Madhya Pradesh) 1.652 bcm; Nagarjuna Sagar (Andhra Pradesh) 1.082 bcm; Ukai (Gujarat) 0.976 bcm; Pong (Himachal Pradesh) 0.913 bcm; Gandhi Sagar (Madhya Pradesh) 0.899 bcm; Rihand (Uttar Pradesh) 0.734 bcm; Bhakra (Himachal Pradesh) 0.668 bcm and Koyna (Maharashtra) 0.598 bcm.