Scientists continuously develop more detailed and more powerful climate models, which make much more accurate and useful predictions for the state of our environment in the near future. But how much can we really extrapolate the results for the future- 10, 100, 1000 years?
Now that pretty much everyone, with a few confused exceptions, has agreed that climate change is upon us, scientists, governmental officials, environmentalists, and even corporate giants, have joined forces to mitigate it in any way possible. The past year has already been record breaking for renewable energy technologies, more and more politicians are raising awareness and introducing policies to reduce levels of pollution. All in all, finally tackling raising temperatures and sea level have become a common global goal and challenge.
Most measures and plans are based on scientific predictions that have come out of complex and very reliable climate models. These are essentially computer simulations, which take into account a complex combination of variables, such as solar radiation, air temperature, emissions, among many others, and analyze their temporal change over a certain number of years. Trends come out that show how certain variable of interest, lets say temperature or sea level rise, has changed over the years, and these trends are then extrapolated over the future n-number of years.
The more simple models assume that the rate with which all variables have been changing in the past, will remain the same, while more complex models give a set of scenarios, which simulate what would happen if one (or more) of the variables start behaving differently. For example, let’s say we manage to eliminate all carbon emissions from the industry, then the model could tell us what effect this would have on the general trend.
Now, you can probably imagine that the more simple a model is, the more questionable its results would be. Such models give sloppy results, and allow unjustified assumptions, which consequently are in fact the reason for climate change deniers to exist. A recent article published in Mail&Guardian Africa, demonstrates this perfectly.
In the piece, the author looks into the effect deserification and sea level rise will have on the African continent in future. So far it is all well and good, both events can in fact have devastating impact if no actions are taken, but the figures that are presented are just a little too hard to imagine.
The author “crudely assumes” that the rate of sea level rise that we have observed over the past century will remain exactly the same for the coming 1000 years. 48 of the African countries, will be directly affected, meaning that 25% f the African population, who live in a buffer zone of 100km off the sea coast will suffer. There are also quite detailed analysis on agricultural production, economic state of the affected countries, and same projections are made for year 3015.
But why did the author do this? I wonder, especially since if we go back 1000 years in time, actually not even that long back, we will see that in the 16-17th century the world was experiencing the Little Ice Age, and I am pretty sure that no model could have foreseen our current state.
I believe that journalists, bloggers, scientists, even governmental officials, should base their statements on convincing facts, and raise awareness rather than panic. If a model, or a data set is, is based on solid evidence, it is much more likely that it will convince people to take an issue seriously and act. Else, it will just divert the attention from the actual problem, to a pointless discussion on how unreasonable it is to claim that half of Africa will be under water in 1000 years.
Image (c) getty