Brief Description: While there is still debate and conflicting views about the level of accuracy of the various projections and scenarios related with climate change, and the measures that need to be prioritized now for tackling possible impacts and consequences in the future, there is nevertheless a growing consensus that the global climate is changing.
The world is becoming warmer and extreme weather conditions such as tropical cyclones, strong rain with flooding or long dry periods have increased in the past years . Within this context, a critical understanding is that it is the human influence that is largely responsible for these rapid shifts in weather patterns that are quite possibly pushing the earth’s climate beyond a tipping point where certain adverse impacts and consequences may become irreversible.This alarming realization is now lending a sense of global urgency for devising appropriate systems, processes and methodologies to meet this challenge.
Trace gases such as water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (laughing gas N2O), and ozone (O3) though only show up in very slight amounts in the earth’s atmosphere, have a substantial impact on climate: all have the similar effect as glass windows do in a green house. They allow sunray of shorter wavelengths to pass, while filtering longer wave lengths of radiant energy by partially hanging the sun rays after reaching the surface. These gases are therefore known as green house gases. They are responsible for the natural green house effect that keeps the earth’s average temperature at about 15 °C – without them about - 18 °C. The natural green house effect is what makes life on earth possible.1 However, human activities such as the combustion of fossil fuels, industrial pollution, land use changes and deforestation, among others, have enhanced significantly the concentrations of GHGs in the atmosphere together with a reduction of the capacity of oceans and vegetation to absorb GHGs. This is referred to as an additional or manmade green house effect. With regard to this, carbon dioxide plays a key role. Its participation in the man-made greenhouse effect is placed at approximately 60 % with about three quarters of the manmade increase in CO2 resulting from the burning of fossil fuels .