Nieuws - 15 september 2011

Climate change

Plants and animals appear to be able to migrate to cooler territory faster than was believed for a long time. This ability enables them to keep one step ahead of global warming.

This finding could be read in various national dailies after it was published in Science by British researchers. We are talking about an average of more than one kilometre per year. That is measured horizontally. Uphill is harder, and then the distance is no more than a couple of metres.
It sounds like good news and something to counterbalance all the scary predictions that are always being tossed around. Anyway, is all this gloom and doom about an imminent loss of biodiversity justified? The following is worth pondering. Models do not take local variations into consideration. On one hillside there are always little patches with a different level of exposure or more shelter to be found in a small area. Move one metre and you can be out of the burning sun. And then there is the influence of the human beings managing the vegetation. In the hillside woods of South Limburg, there are fewer warmth-loving species than there were 50 years ago, in spite of climate change. This is because it has become cooler in the woods since felling stopped. And lastly: not all plants and animals are so easily defeated, any more than humans are. The famous ice age relics are a case in point.
Of course there are all sorts of examples which illustrate the opposite effect. All I am saying is that it is not so simple. One thing is certain: there are a great many new species arriving in the Netherlands. So let us make sure we enjoy them, at least. Preferably sitting in the warm sun at a pavement café.