crop Archives - The India Climate Observatory

Being prudent about forecasts

June 3, 2015 by Climate portal editor Leave a Comment

The Earth System Science Organisation (ESSO), Ministry of Earth Sciences (MoES) and the India Meteorological Department (IMD) released their second long range forecast for monsoon 2015 on 2 June. The ‘headline’ message is that rainfall for the June to September monsoon season is very likely to be 88% of what is normal for the season.

The forecast has been seized upon by various quarters as having serious implications for the production of crop staples (and therefore for food security), for farmers’ livelihoods, for consumer prices and for the availability of water. These are all valid and important aspects that depend entirely or substantially upon the summer monsoon.

But, the IMD, the ESSO and the MoES do not make statements and forecasts on these aspects. They are concerned with what the climatological data and signs point to, and that is what they have told us. How the forecast relates to important aspects of food, farm incomes, water resources and food stocks relies on interpretations. Our advice – to the media, to government agencies and to the private sector – is to go slow on drawing conclusions and when conclusions are required, to make them incrementally.

The wettest pre-monsoon season (March to May) for five years.

Using the handy graphic here, (887KB) we also point out that the pre-monsoon season (March to May) for 2015 has been the wettest in five years. In several meteorological sub-divisions, excess rain has been recorded during this pre-monsoon season. In several districts, the annual rainfall total has already been reached, even before the typical monsoon season of June to September.

This ought to be warning enough to us to be sparing with deciding how forecasts will affect us. The ESSO, IMD and MoES have repeated, in their second long range forecast, that 2015 is an El Niño year which only means that as this sea temperature phenomenon waxes and wanes though the remainder of 2015, so too will the monsoon system react.

It is best to judge our Indian summer monsoon a week at a time, keeping in mind crop calendars and how much water our reservoirs hold. It is always prudent to take precautions such as rationing water (even when it is raining), especially in towns and cities. Likewise, district administrations will do well to assess their local supplies of food staples and match these figures with what food staples their districts are likely to produce during a monsoon whose reliability has now been written off.

The second long range forecast for monsoon 2015 is available here, and the Hindi text can be found here.

Rain, climate, agriculture and Haryana

May 4, 2015 by Climate portal editor Leave a Comment

Every one of Haryana’s 21 districts received excess rain for the period 1 March to 30 April 2015. As these rains have destroyed crops, including food staples, the need to compensate the affected farming families is now paramount. Relief and support are only useful when they are arrive quickly, and unlike administrative conditions two generations ago, state governments and district collectors today can consult data around the clock about conditions in districts and blocks.

Our infographic shows why the March and April rains in Haryana have had destructive effects. The average rainfall in a district of Haryana during this two-month period was 111.6 millimetres – most were in the range of 148 mm (like Ambala) and 81 mm (like Mahendragarh). However, the average for the two months, March and April, is 21.2 mm (Panipat and Faridabad are usually closest to this average).

Although the level of detail available at the district, and indeed even at the weather station level, is comprehensive, the Indian Meteorological Department’s rainfall quantity categories are not granular enough to describe what Haryana has experienced. (This is so for every state that has recorded what is called “unseasonal rain” in these months.)

Amongst the questions that remain unanswered concerning the ‘unseasonal rains’ phenomena – common to Haryana, eastern and western Uttar Pradesh, Bihar, Madhya Pradash, Rajasthan and Gujarat – is the matter of how much rain becomes excess over how many days? This meteorological sub-division (Haryana, Chandigarh and Delhi) normally receives 165 mm in July and 173 mm in August. Therefore, an average amount of 111.6 mm over two months is not a quantity that has surprised the agricultural community.

The matter is one of timing – which lapse the state administration needs to explain, as the weather forecasters first alert state administrations, which then relay alerts and advisories to district administrative staff. Between the claims for compensation for destroyed crops and the political point-scoring, the state government of Haryana has side-stepped the question: what did it do with the weather advisories it was given in March and April 2015?

For our series on the changing rainfall and climate patterns (the Haryana map is the first), we use six categories that begin with 10% above normal and extend to 1000% above normal. This method does better at identifying districts in which agriculture has been hit harder by unseasonal rains and stormy weather.

A report card on monsoon 2014

October 1, 2014 by Climate portal editor Leave a Comment

From the first week of June 2014 until the middle of September 2014, there have been floods and conditions equivalent to drought in many districts, and for India the tale of monsoon 2014 comes from a reading of individual districts, not from a national ‘average’ or a ‘cumulative’. [This article was published by the newspaper DNA.]

Despite the advances made by our agencies in weather forecasting and climate monitoring, the science of meteorology still remains to be effectively distilled so that it can be used by citizens and, wherever possible, expanded and given context by ground-based observation and recording. One sector in which this does take place – albeit at a level still far below its potential – is agriculture. The reason is clear: our crop staples (the cereals, pulses, vegetables and fruit) have their individual calendars for preparation, sowing, tending and harvesting.

This line chart tells some of the 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 far above normal districts recorded their rainfall, negative numbers show us how far 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 all districts in every week.

And so we have an agricultural meteorology system that faithfully and reliably informs ‘kisans’ and cultivators in 641 districts what to expect from the weather for the next week. Thanks to mobile phones, weather alerts and crop advisories are distributed in all our major languages to a portion of the farming households working on 138 million farm holdings, (of which 117 million are small). But this is still only a portion, and is far from adequate in distributing the results of the work of our earth scientists and field staff.

Moreover, every other sector of development requires such raw data and location-specific analysis: the Department of Rural Development, the National Rural Health Mission, the Nirmal Bharat Abhiyan (for drinking water and sanitation), the food-based programmes (like the mid-day meals) for which the availability of ingredients and their supply is the essence of their work, the Central Water Commission and the Central Ground Water Board, whose work it is to determine the water flows and balances in river sub-basins and watersheds (there are 3,257), and districts administrations (which administer 232,855 panchayats) and municipal councils alike which must implement relief measures when drought sets in or must ration supply when there are shortages. This is but a small list of agencies whose work is directly affected by the Indian summer monsoon and its activity where they work.

A dense network of weather stations (more of these are being automated every month, but every taluka still does not have one) is complemented by dedicated satellites which provides continuous coverage of the sub-continent, the northern Asian land mass, the surrounding oceans southwards until beyond the Tropic of Capricorn.

The typical IMD map of ‘normal’ rainfall measured by the meteorological sub-divisions. The detailed weekly tables give us a very different picture

Methods to simply and accurately funnel this stream of real-time data and imagery are available, mostly at no cost, in order to aid local administrations, farmers and cultivators, and all citizens. It is this availability and relative simplicity of use (block-level weather forecasts for 72 hours are now available as local language apps on smartphones) that must be encouraged by the official agencies – for they simply do not have the persons to do so at the scale and detail required.

Consider the setting in early July 2014. India’s summer monsoon was already late, and where it was late but active it was weak (as shown by the chart). The indications from the central earth science agencies (including the India Meteorological Department), from the Indian Institute of Tropical Meteorology, from the National Centre for Medium Range Weather Forecasting were that it would be end-June before the summer monsoon system settles over central India and the western Gangetic plains. This did not happen for another two weeks, until six of the usual 16 monsoon weeks had passed.

When in mid-July more rainfall was recorded in the districts, even then, as the chart shows, only 50% of the districts reached their ‘normals’ for that week only. Thereafter, the volatility of rainfall set in and while for those in our towns and cities there was relief from the searing summer temperatures the rains did not assure sowing conditions for farmers and cultivators, nor did it add, in July, to the stores of water in major and minor reservoirs.

That is why the IMD’s outdated and stodgy public outreach practice must be overhauled, completely. The bland map (see example) of sub-divisions is of little use when what we want to know pertains to tehsil and town. The Met Department’s rain adequacy categories must be replaced too by measures that are geared towards aiding alerts and advisories – ‘normal’ is rainfall up to +19% above a given period’s average and also down to -19% from that same average, a range that can make or break the efforts of a horticulturist.

This table illustrates the trend of weekly rainfall in 40 districts. These districts are selected as being home to the largest rural populations, two from the 20 major states (by population). The numbers by week and district describe how far from a ‘normal’ the recorded rainfall for that week was.
Several overall observations stand out. Districts with weeks coloured light rose dominate, for these show those that received much less rain than they should have. Districts with a shade of deeper blue are the next most frequent category, and those received excess rain. Taken together, this tells us that extremes – very much less or more – were common for this group of districts in India with large rural populations.
We can see the prolonged dry spells for districts in Haryana and Punjab; likewise the absence of rain for the first six monsoon weeks in Gujarat and Maharashtra; are examples of wide swings around weekly ‘normal’ in Giridih (Jharkhand), Muzaffarpur (Bihar), Haridwar (Uttarakhand), Mandi (Himachal Pradesh), Viluppuram (Tamil Nadu), and Mahbubnagar (Andhra Pradesh). The weeks ending 20 August in Bihar and the weeks ending September 3 and 10 in Jammu and Kashmir immediately stand out – the Kosi had breached its banks in Bihar and the Chenab submerged Srinagar and Jammu.

Likewise, excess is +20% and more, deficient is -20% to -59% and scanty is -60% to -99%. To illustrate how misleading these categories can be, the difference between an excess of +21% and +41% can be the difference between water enough to puddle rice fields and a river breaking its banks to ruin those fields. [Get a full resolution image of the table here, 1.85 MB.]

The yawning gap between the technical competence of India’s climate monitoring systems, and they ways in which they are used, must be bridged and this is best done through public participation and citizen initiative. The politics of monsoon and of water will continue, but must not be allowed to define how our systems are used. Nor must they detract from our long history of weather observation, which dates back at least to the ‘Vrhat Sanhita’ of Varahamihira.

It has only signalled policy confusion for central and state governments to have not declared districts and talukas as affected by drought – which they should have by late July 2014 – while at the same time quietly announcing to administrations, as the Ministry of Agriculture did, that “to deal with challenges posed by delayed and aberrant monsoon and in the wake of shortfall in sowing of major crops during kharif 2014, the government has initiated interventions”. These being a diesel subsidy for what is called ‘protective irrigation’ of crops, raising the ceiling on the seed subsidy, rolling out a drought mitigating programme for horticulture, boosting fodder cultivation through the flagship Rashtriya Krishi Vikas Yojana.

The new government has stated time and again its desire to improve and strengthen governance. This must come to include a concerted drive to democratise the use of public domain information, including our monsoon and water, in order that we residents of 4,041 statutory towns (large cities included) and 3,894 census towns can judge for ourselves the relationships between the food we buy, they rain we receive, our individual use of about 70 litres of water a day, and the fluctuation of these trends from one monsoon to another. The moral of monsoon 2014 is that we must reclaim local measures for local use.

Rahul Goswami

The IMD’s shaky monsoon math

August 7, 2014 by Climate portal editor Leave a Comment

Over eight weeks of recorded monsoon rain, the district-level data available with the India Meteorological Department (IMD) portrays a picture that is very different from its ‘national’ and ‘regional’ advice about the strength and consistency of rainfall.

In its first weekly briefing on the monsoon of August 2014, IMD said: “For the country as a whole, cumulative rainfall during this year’s monsoon (01 June to 30 July 2014) has so far upto 30 July been 23% below the Long Period Average.” Out of 36 meteorological sub-divisions, said the IMD, the rainfall has been normal over 15 and deficient over 21 sub-divisions.

Readings for each district that has reported rainfall consistently for eight weeks. The columns represent the percentage value of actual rainfall for each district against their normal rainfall for eight weeks.

However, we have compiled a far more realistic reading of the monsoon season so far, from the IMD’s own data. For the 614 individual readings from districts that have regular rainfall readings, we have the following: 86 districts have registered scanty rainfall (-99% to -60%); 281 districts have registered deficient rainfall (-59% to -20%); 200 districts have registered normal rainfall (-19% to +19%); and 47 districts have registered excess rainfall (+20% and more).

Moreover, using our running weekly district-level monsoon meter – the details of which and the reasoning for which you will find in here – we see that there was a substantial dip in the number of districts registering ‘deficient 2’ rainfall, which is less than 21% of the normal and lower, during the seventh week of rain, that is the week of 17 to 23 July. But the general trend returned the following week, 24 to 30 July.

What this means, and the bar chart we have provided to illustrate the 614 individual values leaves us in no doubt, is that 367 out of 614 districts have had meagre rain for eight weeks. This also means that over eight weeks where there should have been rainfall that – as the IMD predicted in early June – would be around 95% of the ‘long period average’, instead three out of five districts have had less than 80% of their usual quota.

Our running weekly district-level monsoon meter to aid governance decisions shows the overall trend has not changed substantially in the last fortnight despite good rains during the seventh monsoon week.

Unfortunately, the press and media – in particular the business and financial media – persist in reporting ‘national’ deficits and whether monsoon 2014 will ‘make up’ the average in the remaining period. This approach must be corrected by the IMD’s departmental divisions as it incorrectly makes popular the notion that total rainfall over a designated number of weeks is the most important monsoon metric (See ‘Why there is no ‘normal’ in our monsoon’). Of course it is not so, as different crops follow their own crop calendars according to the agro-ecological regions they are grown in, and require optimum rain at certain times during their respective crop calendars.

The following examples show why such reporting can be misleading:

From Reuters: “August rains hold the key to India’s major summer crops such as rice, soybean, cane and cotton, after a wet end to July failed to make up fully for a dry start to the four-month monsoon season. A late revival shrank the shortfall in rain to around 10 percent below average in July, the India Meteorological Department’s update showed on Thursday, a sharp improvement from the 43 percent deficit in the first month of the season.”

From Bloomberg: “Monsoon crops are sown from June and harvested from October. The country had less than 40 percent of average rains in the first six weeks of the monsoon season that runs through September. The shortage shrank to 23 percent by end-July. Oilseed planting in India is poised to slump as much as 24 percent to the lowest since 2002 after a weak start to the monsoon.”

From The Hindu: “With the country receiving good rain in July, monsoon deficiency has gone down to 23 percent, the MET department on Friday said. While the monsoon deficiency at the national level in June was 43 per cent, by July end it has come down to 23 per cent. Central India, which saw little rain in June, has by now seen some good rain. It received 402.2 mm of rainfall as compared to expected rainfall of 477.7 mm with a deficiency of 16 per cent, much lesser compared to other parts of the country.”

From Business Standard: “According to the India Meteorological Department (IMD), the rains managed to recoup much of the June losses due to strong revival over the central and western regions, and parts of northern India. Weather officials said the momentum of July would continue till about August 10 and then slacken a bit.”

From Mint: “India’s July rain deficit narrowed to 10% of the long-term average for the month, marking a recovery from the driest June in five years, the India Meteorological Department (IMD) said, as kharif crop sowing picked up in tandem. The shrinking of the rainfall deficit in July comes at a time when policymakers have been concerned about the impact of a below-average monsoon on foodgrain production and inflation. The June-September monsoon accounts for more than 70% of the annual rainfall in India and irrigates crops grown on half the country’s farmlands.”

Seeing the local in six rain weeks

July 23, 2014 by Climate portal editor Leave a Comment

RG_ICP_20140723_pic We urge the Ministry of Earth Sciences, the India Meteorology Department and the Ministry of Information and Broadcasting to cease the use of a ‘national’ rainfall average to describe the progress of monsoon 2014. This is a measure that has no meaning for cultivators in any of our agro-ecological zones, and has no meaning for any individual taluka or tehsil in the 36 meteorological sub-divisions. What we need to see urgently adopted is a realistic overview that numerically and graphically explains the situation, at as granular a level as possible.

Using a revised categorisation of rainfall sufficiency levels (the method and the reasoning is available here) we find that for the fifth and sixth weeks of monsoon, there has been a small improvement which does not lower the high likelihood of drought conditions becoming prevalent in districts and scarcity of water for our settlements. The full-size chart is available here as an image, and explains in detail the rainfall that districts are reporting.

The fifth monsoon week is 03 to 09 July 2014 and the sixth monsoon week is 10 to 16 July 2014. There has been a small addition to the revised normal rainfall category (-5% to +5%), rising from 18 districts recording normal rainfall in the 4th week to 22 in the 5th and 28 in the 6th. There has also been an improvement in the number of districts recording deficit-2 levels of rainfall (-21% and more) with 437 in the 4th week, 411 in the 5th week and 385 in the 6th week. For the remainder of July the likelihood of more rainfall in the districts that have recorded normal or excess-1 (+6% to +20%) is small, according to the available forecasts, and this means that monsoon 2014 will begin August with far fewer districts registering normal rainfall than they should at this stage.