Simulations
Another group bases its assumptions on computer models and expresses the opinion that there is more likely to be an increase in the potential intensity of such low-pressure vortexes (cf. Fig. 6).
Finally, there is a third group which considers the influence of climate change to be negligible compared with the strong natural fluctuations in frequency and intensity, e.g. in conjunction with the El-Niño/La-Niña Southern Oscillation (ENSO) in the Pacific or the North Atlantic Oscillation (NAO).
They draw attention to the extraordinary hurricane activity in the North Atlantic and Caribbean in the 1950s and 1960s, which was not observed again until the mid-1990s. But this should not make us feel any safer: if more energy is transported into the lower atmosphere and the oceans as a result of the greenhouse effect, it will probably lead in the long term to an intensification of energy exchange and transfer processes.
After all, this is how tropical cyclones work. Changes in sea surface temperatures, ocean currents, and atmospheric circulation will inevitably have an effect on the tracks and intensity of cyclones. The cyclone off the coast of Brazil in March 2004, the first ever observed over the tropical South Atlantic, may be regarded as a warning signal. Water temperatures in this region had always been too cold for such a development.
Perhaps we now have confirmation of the long-held fears that the densely populated coasts of Brazil could one day be threatened by hurricanes. Similar fears for the coasts of western Europe, however, would appear to be highly If we draw together all the connections between global warming and its various effects, we end up with a long list of more or less certain changes that should be incorporated in medium- and long-term prevention considerations (cf. table 3).
In addition to this, there will inevitably be other feedback mechanisms in the atmosphere, the oceans, the ice sphere, and the soil, of which scientists have only a very vague idea as yet. One of the biggest questions at present centres on the possible reactions of the oceans, since they may have a significant impact on the future course of global environmental change. Major surprises are therefore inevitable.
This makes it all the more important for mankind to get a grip on its hitherto completely uncontrolled "experiment with planet earth". Otherwise, the immediate repercussions in the form of natural catastrophes and the long-term effects like the shifting of climate zones could become an existential threat to the world's constantly growing population.