By Ranil Senanayake –
This year is a signal of things to come and yet, not only are we ill prepared for the effects of climate change, but we are also gleefully adding to the problem by burning more and more fossil fuels to supply our energy needs. The new studies on global temperatures suggest that they will exceed all records this year. The map below that depicts the rise in temperatures over average suggests that we narrowly escaped a disastrous heat wave. The map shows Sri Lanka only just above the ‘record warmest’ band.
Why is a heat wave so dangerous? Apart from the heat stress in human and animals, it could exceed the threshold for enzymatic activity. All of agriculture depends on the good growth of plants, all plants rely on their chlorophyll to grow and produce. Chlorophyll is a molecule that functions to an optimum at about 37degrees, above that their performance falls. In heat waves often exceeding 38 degrees plant productivity will be impacted and yields drop (fig2). This year much of Australia dealt with a brutal spring heat wave that reduced farmers’ yields.
The danger to agricultural production is further exasperated by the reliance on chemical farming with so-called ‘high yield ‘ crops. These crops have been bred by reducing photosynthetic biomass for crop biomass. This reduction being made possible by the use of chemical fertilizers. But in a high temperature situation when chlorophyll is functioning sub-optimally such reductions may bring serious crop losses.
Chemical fertilizers are produced using large amounts of energy, usually fossil energy. The creation of this fossil energy results in the discharge of huge volumes of Carbon Dioxide into the atmosphere. Therefore chemical farming adds greatly to global warming, that creates the dangerous heat waves around the planet and finally affects the farmer through increased heat stress on the crop.
Another contributor to local warming is the massive urban infrastructure, not only does it contribute to an increase in carbon dioxide emissions through the use of cement, which is estimated to produce sixteen times more than an equivalent volume of oil; it also increases he daytime heating of the concrete producing ‘heat islands’ where the local heat is higher than the ambient. Poor air circulation and quality in cities where air quality is not stringently controlled, creates pollution at levels where, in Delhi for example, where it has been estimated that “The pollution in the city kills at least one person every hour and impairs the lungs of every third child’. Thus city creation must be approached with extreme caution and sound planning.
We have had a plethora of conferences and discussions about adapting to Climate Change. Sadly there has been no address of the fact that it is ‘Fossil Driven Development’ that as brought us to this sorry state. It is even more tragic, to witness so- called ‘informed politicians’ promoting fossil driven development as a good thing for Sri Lanka’s progress. We need some informed planning to adapt to the oncoming changes. And, to help planning to the changes is it not time to begin mapping out the temperature sensitive regions of the island and begin develop some functional responses, especially in the agricultural zones?