Getting Heated Up
by K P Prabhakaran Nair on 21 Sep 2013 2 Comments

The aberrant weather pattern India has been experiencing of late has led to many speculations, some dire, some benign, and some others outright dismissive. The reality is somewhere in between. As an international agricultural scientist working in three continents (Europe, Africa and Asia) for over three decades, I had foreseen perceptible changes in the weather pattern in India because I work with both soils and plants.

 

Soil is an invaluable gift of God to life on planet earth, and can aptly be described as the Soul Of Infinite Life (soil). This is how I described soil at an important international conference on global soil management in Hamburg, Germany, that I attended as a key speaker in the opening session some thirty years ago. The participants were quite frankly amused when I alluded to soil as the “soul of infinite life”. During the coffee break they asked me why I called soil a “soul”. Let me explain. 

 

We talk of water at great length, “water conservation”, “water management”, and what not, but why are we not talking about soil and water, and not soil or water alone? Without soil, there is no water. Water cannot exist in outer space as it can in soil, except in the form of vapour. In the soil, it is in its original form as H2O – hydrogen bonded to oxygen. Let me explain.  

 

Soil has three principal particle size components, clay, silt and sand, of which the clay particle (less than 2 Angstroms in size, one Angstrom = 1/1000th of a millimeter, the unit named after a famous Swedish physicist), is the seat of all very dynamic electro-chemico-physico reactions. The surface of a clay particle carries excess negative electrical charge, while the silt particle carries some electrical charge and sand carries nothing. It is this excess negative charge that sets off a chain of fascinating and very dynamic reactions.

 

A molecule of water has a hydrogen atom and an oxygen atom. The hydrogen atom carries a positive charge, while the oxygen atom carries a negative charge. The hydrogen atom is at the periphery of the molecule. Because of the positive charge it carries, it is electrically attracted to the excess negative charge on the clay particle to affect an electrical neutralisation or electro-chemical atomic balancing process.

 

But, as the hydrogen atom is already bonded to an oxygen atom, because of its negative charge, an electro-chemical bonding results. A chain of water molecule is thus built around a clay particle, and this chain extends further with more and more water molecules and contributes to what we know as “soil water”.  

 

This is how the water from rainfall, which does not percolate into the sea, is held in the mass of soil. This also explains why Indian soils carrying a large amount of clay, like the alluvial soils of the Terai region in the foothills of Himalayas, conserve a lot of water, while the coastal soils of Kerala, with so much of sand cannot hold enough water when it rains heavily, and the water simply runs off to the Arabian Sea, and in the process carries away a lot of top soil from agricultural fields.

 

In the former, water is well stored, while in the case of the latter, almost all the rain water washes itself off the soil surface as “run off”. This also leads to the logical conclusion that while the former is termed as “fertile” and “productive” soil the latter is described as “infertile” soil. A critical examination of rice and wheat growing in these two areas clearly show why we get very good crop yields in the Terai region, while not in the sandy soils of Kerala. The crucial question, though, is what has all this got to do with climate change?

 

Soil is the repository of a load of carbon atoms. A fertile soil has tons of it, infertile sandy soil does not. A carbon atom has a great capacity to absorb and retain heat; sandy soil with low carbon content does not. The reader will understand when I compare the climate difference between deserts and a fertile soil like the Terai. What happens in the deserts of Gulf countries? Daylight temperatures in summer months are unbearable, but once the sun sets, the atmosphere dramatically cools. All radiation is reflected, but not in a dark coloured black soil with a lot of clay content. The reader will understand if he/she has lived during summer months in north India, where both day and night temperatures can be excruciatingly hot. But in a Gulf country, one can take a walk in the desert after night fall. It cools. You can experience this in Rajasthan as well.

 

The above scientific explanations show that soil is a great regulator of ambient heat. So, what are the consequences of this unique property of soil in climate change, when we mismanage our soil resources, as has happened in India for nearly four decades under the chemically-powered industrial type of agriculture, which we have been taught to call the “green revolution”, has brought about environmental havoc? Let me explain.

 

Most of us have been taught or firmly believe that it is automobile emissions and industrial factories which contribute to global warming, because of the emission of carbon dioxide. This is the conventional view of the “text book environmentalist”. If we take the warming pattern, there are two types of gases that contribute to it. First, the “long lived” gases and second, the “short lived gases”. For example, when an automobile moves, the internal combustion engine sends through the exhaust of the car mostly carbon dioxide and carbon monoxide. On the other hand, when a woman sprays an expensive perfume on her body or clothes, minute vapour-like particles crowd the atmosphere, which are called aerosols. Carbon dioxide belongs to the “long lived” gases category, while the aerosol in the perfume belongs to the “short lived” gases category.

 

Both can trap sunlight and retain its heat and that contributes to global warming. These are called “green house gases” (GHGs). Yet, there is another long lived gas which many are unaware of, or pay only fleeting attention. And that is nitrous oxide (N2O) and its main source is human activity, primarily, agriculture. Let me explain how this happens.

 

In 2011, N2O emissions into the atmosphere accounted for about 5 per cent of all the GHGs in the US originating in human activity, primarily agriculture. N2O is naturally present in the atmosphere as part of the Earth’s N cycle, and has a variety of natural sources. However, agriculture, especially the high input industrial type agriculture, is the main contributing factor. When urea or ammonium sulphate or any other fertiliser carrying the nitrogen plant nutrient is applied to soil to supply nitrogen to the crop, there is a chemical reaction in soil, called “hydrolysis” (mixing of the urea or ammonium sulphate granule with water) and while the plant can take up the nitrogen from this fertiliser only as an oxidised molecule (NO3, called nitrate), another by-product escapes into the atmosphere, as N2O, the nitrous oxide, which is the real culprit.

 

The nitrous oxide has the capacity to capture an enormous amount of energy (heat) from sunlight, and retain the energy, leading to global warming. The N2O molecules stay in the atmosphere for an average of 120 years before being removed or destroyed by chemical reactions. The impact of 1 pound of N2O on global warming is over 300 times more than that from 1 pound of carbon dioxide. N2O is emitted when farmers add to the soil synthetic fertilisers like urea. Agricultural soil management is the largest source of N2O emissions. In the US, it accounted for about 69 per cent of the emissions in 2011. Hence, one can imagine the extent to which this gas can contribute to global warming.

 

The crucial question is why are we not talking about this obnoxious gas which is the more dangerous polluter than carbon dioxide? It is because of the financial and political clout of the fertiliser industry. Take the example of what happened in India from the early 1960s.

 

The “miracle” dwarf wheat variety brought to India from the International Centre for Maize and Wheat Research (CIMMYT) in Mexico needed high doses of nitrogen fertiliser to produce maximum grain yield. India had no fertiliser manufacturing facility in those days.  All the nitrogenous fertilisers needed to boost yields of the dwarf wheat were imported from the US. In fact, Indian soils became the dumping ground for fertilisers imported from the US.

 

It is important to note in this context that in the post Second World War period, all the chemical factories in the US which manufactured war chemicals began shutting down because there was no demand for war chemicals, causing unemployment. The Haber-Bausch process required for the manufacture of synthetic nitrogen fertiliser was activated and these factories were made to manufacture synthetic fertilisers, principally nitrogenous fertilisers. 

 

India became the biggest dumping ground for these fertilisers as Indian farmers saw spectacular yield increases in the dwarf imported wheat variety. The central government in New Delhi put in place an agricultural policy whereby thousands of tons of this dwarf wheat variety like the “Sonora” was imported from the US. The farmers in Punjab took to this high input agriculture in no time and Punjab became the “cradle” of the so-called green revolution. Nitrogen fertiliser use was unbridled.

 

But by the early 1970s, yields started to plateau or decline. The soils started getting degraded, ground water was loaded with nitrates, rendering the water non-potable, and aquifers dried due to excessive use of irrigation water; finally, bio diversity started to completely vanish due to the rice-wheat monoculture. In fact, a terrible environmental disaster was rapidly building up. N2O emissions peaked, and, none, least of all the soil scientists, cared to make a balance sheet on the excessive build up of this obnoxious gas in the atmosphere. 

 

Ambient temperature was gradually scaling up. Summers were becoming hotter. The idea of “carbon foot printing” was totally unknown. Worse, the ability to sequester carbon in soil was not studied in detail (“sequesteration” is a locking up process of carbon in soil to enhance its fertility). Punjab, Haryana and western Uttar Pradesh formed a belt of environmental disaster, and all environmental activists pointed a complaining finger to excessive industrialisation  as the culprit for global warming, totally neglecting (possibly deliberately?) what was happening in the soil due to excessive build up of nitrous oxide. 

 

Another very important gas that contributes to global warming is methane (CH4) emission, which is contributed by India’s wet paddy cultivation. Though a “short lived gas”, it is much more potent in trapping much heat and contributing to global warming, like nitrous oxide. Its emission has increased by 150 per cent as compared to carbon dioxide emissions. A lot of paddy cultivation in Punjab and Andhra is through copious irrigation and the standing water contributes a lot of methane gas. One can smell the gas when walking through huge and widespread paddy fields. This is yet, another example where high input industrial type agriculture contributes to global warming.   

 

In this connection, we need to look at some important data contained in the UN Intergovernmental Panel on Climate Change (IPCC), scheduled to be made public by the end of September this year. Global climate in the past decade and a half has not been warming up at rates earlier predicted. In fact, the rate of warming from 1998-2012 at 0.05 degrees Celsius per decade is comparatively lesser than that during the six decades between 1951-2012, which is 0.12 degrees Celsius per decade. In absolute terms, between 1951 and 2012 (six decades), the increase was 140 per cent, which is nearly 24 per cent per decade, which is a substantial increase, compared to 1998-2012. This shows that the rate of increase in global warming is much lower now than what pessimists try to make out. This is no solace. In India, we have many other contributory factors, which are quite worrying.

 

The UN IPCC report warns that a large part of the changes described above cannot be reversed even after the next few centuries, unless the emissions are brought down fast. It is here that Indian agriculture has to change its direction. For one, our mindless and unbridled use of chemical fertilisers, especially nitrogen carrying fertilisers like urea, has to be scaled down dramatically. We are sure to come up against an organised campaign by the fertiliser lobby, if we take up this battle. Under the slogan of producing more, farmers will be prodded to use ever more nitrogen carrying fertilisers like urea. Indian farmers have to be weaned away from the mindset that only chemical fertilisers sustain and increase crop yields.

 

The successful campaign by the Centre For Sustainable Agriculture in Hyderabad, where a large group of farmers have established a successful story of organic farming, devoid of all chemicals, in Warangal district, is a lead in this direction. There is a fallacy of thought that shift from exclusively chemicals dependent agriculture to organic agriculture leads to fall in crop yields. The experience of this author is that for the first three years the shift leads to crop yield loss, but thereafter the yield stabilises. This is also the lesson from Europe, especially Germany, where there are hundreds of organic farms, cultivating thousands of acres. 

 

The IPCC summary notes “It is very likely that more than 20 per cent of emitted CO2 will remain in the atmosphere for periods longer that 1000 years after anthropogenic emissions have ceased. CO2 –induced warming is projected to remain approximately constant for many centuries following a complete cessation of emissions”. This will have long-lasting impacts on the environment. It is virtually certain that global mean sea level rise will continue beyond 2100 feet, with sea level rise due to thermal expansion to continue for many centuries. It is almost certain that if global mean temperatures rise and stay on a sustained basis between 1 and 4 degrees Celsius, the Greenland ice sheet could all but disappear and the cause would be accumulating carbon dioxide.

 

Unfortunately, no measurements on the other two obnoxious emissions, namely, nitrous oxide and methane, have been made. This is where Indian meteorologists, especially those connected with agriculture, like the monolith Indian Council of Agricultural Research, have to play a much more proactive role than at present. There is a lot of “hot air” going round in conferences, both national and international, but little action on the ground. The last Global Climate Change Conference of the “Conference of Committed Parties”, held in Copenhagen, Denmark, attended by some of India’s perpetually pontificating scientists, is a classical example of national waste.

 

What is the political angle to all this? The US has repeatedly warned at earlier climate negotiations that it is not keen to share the burden of reducing emissions with other countries based on the principle of “historical responsibility”, or what it’s earlier industrial impact contributed to climate change. The European Union also is following, albeit covertly, a similar line of thought, though it has shied away from coming out explicitly with this view.

 

Largely, their positions at the climate negotiations suggest that they are open to having a burden-sharing formula to limit future emissions. But they are averse to factoring in responsibility for accumulated carbon dioxide emissions. In other words, they also are toeing the US line, cleverly. Only Japan has sternly and steadfastly stuck to limit the emissions clearly enunciated in the Kyoto protocol. The idea of an overall carbon budget which is already more than half consumed inequitably will naturally be raised at future climate negotiations by developing countries, especially emerging economies like India. That is where India can expect a real road block.

 

What is India’s position vis-à-vis the above scenario? India would soon be in a very sticky position. Its per capita emission is one of the lowest among the large emerging economies, while that emerging economies like China has raced forward. India will require greater carbon space, and therefore time to let its emissions peak than other developing economies like China, or even Brazil. But this is not going to be an easy task, given the global scenario, vis-à-vis the political posturing of different countries, some clear, but others opaque.

 

Given the daunting unfolding scenario on climate change, my best bet would be to set our own house in order, not just in the factories, but in our crop fields, as well. It is in this connection that the revolutionary soil management technique, now globally known as “The Nutrient Buffer Power Concept”, developed by this author, comes into play. The concept has made great strides in global farming, especially on the African continent, and much of Asia (Indian agricultural scientists have still not woken up to the concept) that is faced with the acute after-effects of industrial type chemically powered agriculture.  

 

Addendum 

The Nutrient Buffer Power Concept” project was shortlisted for the prestigious US$ 1million Rolex Awards For Enterprise 2012 of The Rolex Foundation, Geneva, for its originality from  over 3500 nominations worldwide; it is the only project selected for this coveted distinction from the Asian continent

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