When Tom Hunt, CCL’s co-coordinator in the Illawarra considered buying a lakeside property in Oak Flats in 2002, he had heard of global warming and the potential for rising sea levels. In this post he kicks off a series exploring in detail everything he then went on to find out about climate change.
When we considered buying the lakeside property in Oak Flats in 2002, I had heard of global warming and the potential for rising sea levels. It probably didn’t make a big difference to our purchase decision, though I remember thinking at the time it was good that the place we were looking at was higher than most. Most houses on the lakes edge are only a metre or two above sea level. The estimates I had seen suggested that the sea level would rise but less than a metre by the end of the century. It seemed pretty safe. We invested and built our dream home.
Back then, I was willing to think “a little more carbon dioxide in the sky should help plants grow”, and “mother nature will balance things out with time”, but conflicting stories in the media made it hard to know who or what to believe. I had seen for myself the receding glaciers in New Zealand. One story I read suggested sea levels will rise 6 metres as Greenland thaws! What if they are right? Will our home become worthless if buyers start thinking that living on waterfront is a liability? (There’s more at stake of course but there’s nothing like your life savings being at risk to get you thinking).
It motivated me to do a little research for myself. Reading from trusted sources, encyclopaedias, recognised science publications and reports from the IPCC (1), I had the following questions in mind – How stable is the climate? Can the sea level change that much? Is the climate really warming? How is carbon to blame? What is the worst that can happen? Don’t the authorities have it under control?
It was very interesting learning about the history of our planet and its climate. I remember hearing at school something like “the aboriginals probably came to Australia across a land bridge from Asia at a time when sea levels were much lower” but I had not given much thought to why and how the sea was so much lower back then. My time at Uni studying maths and physics didn’t tell me much about the environment though came in handy with understanding the discussions in the media. The story actually turns out to be pretty straightforward science, but the waters are muddied by some misunderstanding, some ignorance, and a lot of wishful thinking.
The truth is that climate change is more than just a little serious. It is far more than just my backyard getting wet. It’s a very real threat for the future of our society, and I don’t say that lightly!
It’s only just started to warm – that will continue for centuries, even if we could finally stop burning fossil fuels and destroying forests!
Really big changes to weather patterns are very possible. Think: Sahara becomes an oasis again, Europe becomes a desert again, Asia loses it monsoon rains (that feed two thirds of the worlds population). We don’t know what exactly will happen, but we do know that such things can and most likely will change (2).
The governments talk of limiting warming to 2 degrees (3) by making changes over the next few decades, but I worry that it is too late already.
The reality is that we have already turned Earth’s thermostat up by more than 4 degrees C(4a), it’s just a matter of time before the Earth warms to that level (4b) and sea levels rise 10’s of metres (5).
Continuing to burn fossil fuels at the rate we are is turning the thermostat up by another half degree every decade (6). The overall hope of the Paris climate agreement is that we can reduce emissions to net zero then find some way to turn the thermostat down again before the warming gets too bad. Our country, and many others are still struggling to even agree on plans for the first simple steps of this. There are not yet any practical solutions to removing sufficient quantities of CO2 from the sky!
Our temperature doesn’t appear to us to be changing very quickly, but it is currently increasing more than ten times faster than it has for millions of years (7). Last time Earth had this much carbon dioxide in the sky, more than 5 million years ago, there was little if any ice at the poles and sea levels were much much higher.
The Earths climate is not as stable as most of us would believe.
The last 8,000 years have been stable, yes. Since the earliest human ‘civilisations’, Earths average temperature has strayed less than a degree from the ‘normal’ you and I grew up with. However for most of the time we humans have been on the planet (~2.5 million years) average temperatures have gone up and down as much as 10 degrees C.
We are currently near the top of that range. The temperatures have more commonly been around 4 degrees colder than today, and they have been as much as 8 degrees C lower.
So why are people worried by an increase of a few degrees? That doesn’t sound a lot – but we need to consider climate, not weather. The weather patterns we get are determined by the overall temperature of the system. Sea currents and wind patterns change as the temperatures change.
For example, currently the Gulf Stream in the Atlantic takes masses of warm tropical water north and the winds across the Atlantic take that warmth and moisture across Europe. It wasn’t always like this. You may have heard that the Sahara desert used to be an oasis. Well, much of Europe used to be a frozen desert too. Sea levels and weather patterns can change a lot. Sea levels have been as much as 100 metres lower and 10 metres higher than today’s level, having gone up and down many times during human history.
The climate can be changed significantly and we are doing it
Many things can affect the temperature on the surface of Earth, but the carbon dioxide gas in our atmosphere is the variable with the greatest impact.
For more than 800,000 years the level of CO2 had not exceeded 300 parts per million, until our Industrial Revolution.(8)
It’s now more than 400ppm.
The ‘thermostat’ hasn’t been set this high for several million years, long before humans were around.
The temperature is now rising – it seems slow to us but it is more than ten times quicker than in the past.
We have no easy way of taking these gases back out of the sky and sea
Every tonne of coal, oil and gas we burn is making the problem worse.
This is because these fossil fuels are stockpiles of carbon that mother nature took out of the sky countless millions of years ago and locked underground. It took her millions of years to accumulate it and we have added so much of it back to the sky in just a century or two. Humans currently burn more than 10,000,000,000 tonnes of carbon from coal, oil and gas every year. Yes that is the right number of zeros. Think of that as a block of solid carbon one kilometre long, one kilometre wide and 10km tall. ALL of that goes into the sky and sea permanently! (9)
You would think that the governments of the world would have it in hand, but they are still struggling to effect the changes we need.
Yes they have been meeting every two years since the UN called them to address it, a quarter of a century ago, and some headway has been made.
However emissions are still growing and the CO2 is still rising at a record rate.
Many countries are now doing a lot of good things. Unfortunately ours is not exactly leader of the pack.
We in Australia have been putting solar panels on our roofs and making changes to our power sources. We have some plans for more but we are not doing nearly enough, nor nearly quickly enough to even stem the carbon we are adding to the sky.
Governments, bless them, are driven by the economy, by big business, and by the need to get reelected in the short term. They do listen to the scientists a little, but they seem to listen more to big business, and to the mass of voters. Lets face it – the big miners, on whose back Australia seems to ride these days, stand to lose a lot of money if they stop mining coal, gas and oil. They have the best lobbyists money can buy, and even some paid scientists, still trying to tell us that coal is good. They certainly seem to have convinced Tony Abbott and others in the far right of politics.
This is where I think you and I are best placed to have an impact. We need to open channels to the politicians in power and convince them of the need for action. I have joined Citizens Climate Lobby (CCL) which has I think, the greatest chance of a positive impact. The aim is to befriend our MPs and engage them to consider implementing a simple solution that can be acceptable to all sides of politics. I hold a great deal of hope with the fast growing CCL movement.
Our civilisation, our enormous global society, is geared to the way the planet is now. Changes to the climate of the size we can expect will be a huge disruption. We don’t want to lose all the coastal cities, we don’t want vastly different weather patterns, we don’t want massive migrations. Consider that two thirds of the world’s population are fed by the monsoon rains that sweep across India, Asia and China. What if it changed significantly? Where would those 5 billion people want to migrate to?
There’s a lot more I want to say, but that is enough for a ‘summary’ and first post. I will add further detail to the CCL blog for you in weeks to come.
You may question something I have said here. Some things appear to provide contradictory evidence but having checked out all the arguments I’ve heard about I am still confident in what is presented here. But I’m open to new ideas, and am always willing to do more research or answer your concerns. Please let me know at email@example.com
1. IPCC – Intergovernmental Panel on Climate Change – the body set up by the United Nations combining the knowledge from the top climate scientists from each nation.
2. I have written more on this – future blog post ‘”What is the worst that could happen?” or email me
3. This is my assessment based on the data I have seen. The IPCC are far more conservative, but even they state that we have only a 1/3 chance of staying under 2 degrees at this stage.
4 (a)Wikipedia: https://en.wikipedia.org/wiki/Carbon_dioxide_in_Earth%27s_atmosphere “About 34 million years ago, the time of the Eocene–Oligocene extinction event and when the Antarctic ice sheet started to take its current form, CO2 is found to have been about 760 ppm,  and there is geochemical evidence that concentrations were less than 300 ppm by about 20 million years ago.”http://cdiac.ess-dive.lbl.gov/trends/co2/ice_core_co2.html The highest pre-industrial value recorded in 800,000 years of ice-core record was 298.6 ppmv, in the Vostok core, around 330,000 years ago.
4(b) How hot is ‘unbearable’? – good topic for a blog post – will work on it!
5. See blog post on Sea Levels (to come)
6. See blog post on Carbon (to come)
7. The average rate of temperature rise over the last 40 years is more than ten times faster than any sustained rate seen in archaeological evidence covering the last several million years. See blog post “How stable is the climate?’
8. “The highest pre-industrial value recorded in 800,000 years of ice-core record was 298.6 ppmv, in the Vostok core, around 330,000 years ago.” http://cdiac.ess-dive.lbl.gov/trends/co2/ice_core_co2.html
9. Permanently? Well not quite, but mother nature takes a long time even when at her best. Geological evidence indicates natural CO2 reduction at best as something like 100th the rate that we are currently adding it. Perhaps more correct to say, as the IPCC put it, “for at least the lifetime of our society”.