The only environmental issue to have caused as much debate and discussion as climate change was probably human population growth. But that is, in some ways, clearer to deal with. We can count how many we are, more or less, and can see a direct effect of more people wanting to use more resources from a fixed stock. Climate change and global warming have become very emotive issues where national and international politics, global economics and the fate of national economies are all bound up with scientific debate about the evidence and cause and effect. Added to this are the questions of whether millions or billions will suffer, whether there wit be losers and winners if climate shifts to a new equilibrium and whether the power bases of different nations will be affected; you can begin to see what a complex issue this is. There are facts that are not in debate:
• There is a greenhouse effect
• GHG emissions are increasing due to human activities and are probably increasing the greenhouse effect
• There has been a recent pattern of increased average global temperature.
There is not total agreement about the cause of the rise in temperature our over what we should be doing about it. The vast majority of scientists working in this field accept the correlation between increased GHG emissions and increased temperature, causing climate change and different weather patterns. But there is a minority who question the cause and effect. some citing the earth's rotational wobble, sunspot activity or that increased temperature is causing increased GHG, not the other way round. And there are climate change deniers. But all agree that the feedback mechanisms are very complex in such complex system as the Earth and that our models, though much improved, may not exactly model the climate.
Adding the question of what should be done — prevention or cure or no action and the inertia that individuals and nation states have in managing change, you can begin to see why there is so much to discuss and how actions lag behind what we think we know. Here, according to the IPCC (Intergovernmental Panel on Climate Change) in their fifth assessment report in 2014:
• Warming of the climate system is unequivocal, and since the 1950s, any of the observed changes are unprecedented over decades to millennia.
• Atmospheric concentrations of carbon dioxide, methane, and nitrous oxide have increased to levels unprecedented in at least the last 800,000 years.
• Continued emissions of greenhouse gases will cause further [global] warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions.
• Human influence on the climate system is dear. It is extremely likely (95-100% probability) that human influence was the dominant cause of global warming between 1951-2010.
This is why we must take immediate steps to address the dilemma and counter unscientific claims that try to make climate change appear as a distant problem. Our future generations will thank us for it.
