Climate Change

Global warming develops slowly, continuously and is accelerating. In the recent 150 years temperatures on earth have clearly increased. It takes a long time to stop this process, decades or more. The warming process reacts very slowly, because warming of the atmosphere indicates a slow warming of oceans and they are, with their large warming-capacity, not able to react fast. The emissions of greenhouse gases of recent decennia, combined with current emissions, lead to a continued global warming for at least the next decades (IPCC, 2007a; b). The second development is that climate changes at a continuous faster pace. It seems that predictions on expected changes are reached sooner and that the climate changes are going faster and the changes are stronger than expected (Tin, 2008). Global warming is accelerating at times far beyond forecasts outlined in, amongst others, IPCC IV. Important aspects of climate change have been underestimated and are being felt sooner. For example the less than 1°C warming the world has experienced to date may have triggered the first tipping point of Earth's climate system: the disappearance of Arctic summer sea ice (Fig. 1.1), which causes at its turn rapid and abrupt climate change. This implies that mitigation and adaptation responses need to be even more rapid and ambitious.

Today, several processes are happening faster and sooner than projected (Tin, 2008):

1. The melt of sea ice in the Arctic Ocean happens 30 year or more ahead of projections;

2. The Antarctic Peninsula is losing faster ice than expected;

3. Since 1990 global sea level rises one and a half time faster than the forecast of IPCC III. This century sea level rise is expected to double the projected maximum of 59 centimetres;

4. The growth rate of CO2 emissions has increased from 1.1% per year from 1990— 1999 to 3% per year from 2000-2004. The latter rate is higher than use in any scenario in IPCC III or IV;

5. Land and oceans absorb 50% of the emissions. The capacity of these 'sinks' is declining at a greater rate than expected;

6. A cut of 80% greenhouse gases at a global level is needed to stay below the, as acceptable declared temperature rise of 2°C in 2100. Which means tat developed countries should achieve even higher levels

The scientific research conducted after the publication of IPCC IV illustrates that the speed and scale of changes that affect the global climate is much greater

Fig. 1.1 Arctic sea ice extent in September 1979, 1989, 1999, 2003, 2007, 2008 (Source: Fetterer et al., 2008; Image credit: Image/photo courtesy of the National Snow and Ice Data Center, University of Colorado, Boulder)

than predicted and it will affect all functions of society: food production, health, ecosystems, water and storm damage.

Because of the long lasting impact of global warming as well as the pace warming takes place, emissions needs to be decreased urgently and it is inevitable for mankind to adapt to climate change as soon as possible. In many countries around the world adaptation strategies are being developed, in every country in different ways.

Was this article helpful?

0 0

Post a comment