14 DAY TRIAL // According to a new scientific study released by experts at the University of Leeds, in the United Kingdom, it would appear that models seeking to explain how Earth's climate will evolve over the years may easily be corrupted by insufficient data about the planet's past.
What researchers mean by this is that past climate trends need to be understood in exquisite detail, before scientists can hope to use their lessons for predicting the future. This is a very important aspect of climate modeling, since scientists expect politicians to make critical decisions based on these data.
Though most models are excellent at teasing out patterns from what happened in the Earth's distant climate past, not the same can be said about the future. The past cannot be changed, and most values that characterized the climate at one point can be derived from a multitude of sources.
But predicting future patterns is not set in stone. Factors to throw the entire system off-balance – for better or for worse – could emerge at any given moment, without any kind of warning. No scientist will ever be able to compensate for the unexpected, and model it faithfully.
In the new study, the Leeds investigators analyzed 11 climate models, of which 8 were established to have reproduced past climate trends with as few errors as possible. But the majority of models could not reproduce the period of global warming that affected the world between 1920 and 1940.
One of the most interesting, and worrying, results was that several models were able to reach the same conclusions by setting out from different premises, and using different methods. This high degree of variation among models is not encouraging, the team says.
“Models reproduced the Arctic and tropical warming from a combination of forcings (e.g. carbon dioxide and particulate changes), feedback mechanisms (e.g. ice melt) and transport of heat in weather and ocean currents,” Leeds expert and study leader Julia Crook explains.
“When we looked at our results we found that the contribution from each term varied considerably amongst the models,” she goes on to say.
“Although climate models agree on the past it is hard to say which model is best, and in the future their different set-ups cause their climate predictions to diverge from one another,” adds study coauthor Piers Forester, a professor at Leeds.
“For this reason it is vital that we use a range of models, and improve understanding of basic processes, if we are to refine our ability to accurately predict the climate patterns of the future,” he concludes.