Question: When do you think the world is going to end due to global warming?

  1. The world isn’t going to end; even if we as a species don’t survive, the Earth will go on without us just fine (want to see a details of how this would happen? Here’s a fun webpage to play with). But if you mean when will human society collapse as a result of climate change, that’s a more difficult question to answer. My understanding of the current trend in climate and the effects that climate change will have on the earth, rising sea levels, animals, and our ability to feed ourselves and find clean water suggests that there’s a few broadly plausible scenarios.

    1). We find and use the technology that allows us to avert the worst of climate change, either by reversing its effects or by working around them, or we wise up and stop damaging the environment this way (or both). There might be a way to stop the increase of CO2 because we discover and use clean energy sources, or it could mean new food and water technology that allows us to still feed everyone even after losing some of our best land to the rising oceans (I’m ignoring the real problem of food inequality across the globe – do you have any idea how much more food and water you have access to compared to many parts of Africa or Asia?).

    2). We ignore climate change, we don’t find the technology to stop it, or it’s already too late. I’d really like to talk to climatologists and other weather scientists here, because this isn’t my field and I’m only giving you broad strokes from what I understand. With that said, you can find publicly available resources (like this Intergovernmental Panel on Climate Change presentation from the United Nations) that give you an idea of what this might look like. The IPCC, one of the most respected international bodies on climate change, suggests that climate change will bring with it a lot of changes, including extreme weather events like heat waves across Europe (and probably here as well!), hurricanes and tornadoes in North America, floods all over the world, sea level rises that swamp some of the smaller islands and coastal areas all over, and droughts that harm our ability to produce food. But the IPCC and other bodies like it are already formulating plans to help deal with these problems, and governments are starting to get in on the action too.

    1 and 2 are the most plausible scenarios; either we find a way to stop climate change, or we find a way to handle the problems that come with it. Don’t get me wrong, scenario 2 is still extremely uncomfortable or even deadly; if that comes to pass, you can expect many more deaths all over the world than there should have been. But it’s also true that the world probably wouldn’t end under that scenario.

    But let’s face it, you’re really looking for the doomsday scenario, the apocalypse. Even though it’s unlikely, we have:

    3). The world ends. How? Well, there’s a number of possible ways that this could happen, and while I think that they’re unlikely, I can take a guess at one for you. Let’s say that climate change goes faster than we expect, and we don’t find a way of stopping it. Much of the polar ice melts, leaving many coastal cities (including Sydney!) missing large chunks of their land now. People are displaced and move inland, where conditions are poor, and food and water shortages break out along with greater incidences of disease. Death rates start to climb as people succumb to lack of food, water, sickness, or sheer heat. National governments fracture under the strain, and smaller regional governments grow up in their place. Law and order struggles to keep up, and in many places the police are completely overwhelmed. Fresh water and food become resources worth killing; at first, riots and skirmishes break out, leading to wars between the new regions as they fight over good farming land and access to water. There’s no more iPhones, as many of the more complex elements of our technology break down for lack of maintenance; computers and other electronic devices become scarcer and difficult to maintain. With the breakdown of global trade, you notice small things like an inability to get fruit that you used to have at the grocery store, or clothes made in China. The monetary system might collapse, and money becomes worthless; humanity reverts back to a barter system.

    Of course, not only is 3 very unlikely, but I’ve just made it up entirely. I really have no idea how to predict that far ahead in the future, even if climate change is worse than we hope, and it’s really just pure speculation on my part.

    I’ve done my best to answer your question, but I really hope that you’ll explore more on your own if this is something that you’re interested in. I have to be clear that I’m a biologist, not a climatologist or a physicist or engineer specialising in issues like this. Everything I’ve written here is my best understanding from what I read mixed with my opinions on human development, but probably half it is wrong and the other half is a mix of possible truth and pure speculation. These sorts of issues are too complex for one person’s opinion! And part of being a scientist is to recognise the limits of your knowledge and to reach out to other scientists when you need help on a challenging problem that cuts across many fields of human knowledge. So you can do that too: talk to your teacher and your parents, find other sources to read, and maybe you can find other scientists to talk to as well.

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Comments

  1. This is a good question toadslayer and Steven has given a good answer, but I might give a different one from the sideline just for fun.
    Not sure about sooner, but, I can guarantee the world will end from global warming in about 4-5 billion years!
    Our sun, which is just another star, will eventually die. But towards the end of its life it will swell up and give off more heat; and I don’t mean just a warm summers day, I am talking, boiling the oceans from the Earth hot. This will kill everything on Earth, and our little home will just be like Mercury, a little hot ball of rock.
    But what ending the earth, in the sense of, the Earth being gone as well.
    The sun will eventually swell up so much that it will likely engulf the earth completely vaporising it, and personally, I would recommend having moved planet long before then.

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  2. Great Q toads layer & Great answer Steven… climate change is incredibly complex, involves all disciplines science and all sectors of society. Much of the debate has been polarised through the media and people arguing about how we should treat uncertainty. One of the things that make it hard to understand is the multiple and cumulative impacts and how much we actually don’t know about our own planet. The scenario approach that you used is becoming the norm as people start to try and predict the impacts. The IPCC use 6 scenarios – each with differing predictions of T increase and sea level rise etc. Some things are likely sea levels will rise by 1-2m by 2100 and T will increase by 2-3C, but there will be local scale variation and some areas will fare better than others – another key challenge for science is taking the global IPCC predictions and downscaling them to local levels. No doubt there will be winners and losers for both habitats, animals (inc humans) and plants. Through my work on marine turtles I know that of the 7 species some will do OK and others are likely be more threatened.

    As society I believe that we should strive for a healthier planet & healthier people…. as the better condition we keep it in the more resilient it will be to change.

    Examples of some of the work that the Aust govt are doing can be found here (Great Barrier Vulnerability assessment http://bit.ly/TlAyTP) & the GBRMPA also have other resources on their website gbrmpa.gov.au

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