Since Kieh l& Trenberth introduced the Global Energy Budget Diagram, many climate scientists/ groups have produced an array of climate models to depict the changes that take place on the globe and atmosphere. Most of these used models – rectangles or cubes – with straight edges addressing only about 25-35 different characteristics of the system.
This need to address more characteristics demanded a new approach and we decided on a circular model and we found it to be better suited for a few reasons. (i) Atmosphere could be accommodated easily around the spherical earth, (ii) Ocean, land surface and roadways could be easily identified and (iii) energy and water flow rates amongst different parts of the total system could be easily illustrated were three major reasons which supported the selection.
There are other models which consist of two spheres depicting the planet earth and the atmosphere encompassing it. They are 3-D models and they have been developed so as to address even minute changes to the system. When you define a minor change to any of the parameters at a particular location, relevant mathematical equations would identify how other parameters would be changed.
We have designed this model with the objective of (a) understanding all possible factors which could lead to climate change, (b) identifying those critical factors which makes significant contributions and, (c) arriving at possible avenues to bring about decent reductions in climate change effect commensurate with cost.
In respect of major contributory factors, the model could address only most significant ones and our opinion is that there are a few large-scale factors through which we could achieve significant benefits and working on minor issues with limited outcomes/advantages will be a waste of time and resources at the current point of time. This is most valid for countries like Sri Lanka with limited resources and impacted most significantly been at 70N latitude. If we go by the model, the worst threats to the global climate or to local climate stems from incident solar radiation which varies with the latitude of the country, amount of roadways present in the country and amount of greenhouse gases emitted by the country.
How this happens is as follows:
(1) When the latitude of a country is low, more and more solar radiation falls on the country. At our latitude, about 400Wm-2 which is the highest possible.
(2) A major component in a country’s surface which will absorb this solar radiation is their roadways because of its black surface and in Sri Lanka it had been 148km/100km2 area in 2014, highest for this latitude.
(3) This much increase in solar radiation absorbed gets reemitted as terrestrial radiation from the earth’s surface creating unbearable global warming.
(4) Greenhouse gases emitted by Sri Lanka at its current value of 590 t/km2 is a very high value putting us within the top twenty global emitters.
(5) Waste heat from our vehicular traffic is more than twice the electricity consumed, while for both USA and even the world they are equal.
This is the message that is intended to be communicated by this Climate Model and it is equally applicable to all countries; but the limits may be different.
For us at 70N receiving 400 Wm-2of solar radiation, a road density of 148km/100km2 and greenhouse gas emission of 590t/km2have already taken us to the list of 10 most vulnerable countries in the world in three years in a row. But for Japan and Germany nearly at about 400N receiving only about 200Wm-2 of solar radiation, road densities of 316 and 180 km/1002 and GHG emissions of 3717 and 2568t/km2 respectively were necessary to bring it to the list. But it is always determined by these three criteria and this new model highlights the same.
The writer is the Managing Director of Somaratna Consultants (Pvt.) Ltd.
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