This is a THEME PAPER ABSTRACT; the paper will be presented at the Jamaica Consultation on Creation Care and the Gospel in October, 2012.  Comments are welcomed!  View all abstracts.

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Impacts of Human Induced Climate Change*

            Human activities, especially the burning of coal, oil and gas are responsible for the emission of about 30 billion tonnes of carbon dioxide together with other ‘greenhouse’ gases into the atmosphere each year. Since these gases act like blankets over the earth’s surface, increases in their concentration causes global warming on average and changes in the Earth’s climate that will result in many adverse impacts.

The most important impacts are:

(1)   Sea level rise of up to ~1 metre per century (~40 cm as ocean waters warm and expand to which is added effects of melting glaciers and ice caps). This will lead to devastating impacts in many low lying regions, for instance, in Bangladesh where about 10 million people live below the one metre contour.

(2)   Increasing frequency & intensity of heat waves such as that experienced in central Europe in the summer of 2003 of unprecedented persistence and intensity resulting in premature deaths of at least 25,000 people. Projections suggest that in Europe such a summer could appear normal by 2050 and cool by 2100.

(3)   Increasing frequency & intensity of extreme events, e.g. floods & droughts, for which events on all continents indicate a clearly rising trend. Their risk could rise by a factor of five or more by mid century, especially in vulnerable areas. Together with sea level rise, these could result in hundreds of millions of environmental refugees – to where will they be able to go?

(4)   Adaptation to the rate of climate change will be difficult for both humans & ecosystems resulting in the loss of millions of species & biodiversity loss.

(5)   Examples of other impacts are acidification of ocean water and release from the arctic of methane, a potent greenhouse gas. In the absence of adequate mitigation, these will result in very serious damage especially in the longer term.

To address these impacts requires both adaptation (immediate & planned) & mitigation (especially drastic reductions in human induced greenhouse gas emissions). Actions of both kinds are urgently needed by individuals, by villages & communities on the local scale, and by national & international organisations and industries on the world scale. For the past 20 years there has been general international agreement that global emissions of carbon dioxide be curtailed such that the global average temperature should not rise more than about 2 deg C above its preindustrial value. Although the means to do this are available and the cost is reliably estimated to be covered on average by savings in fuel, actions with the urgency and on the scale required are not yet occurring.