Before the Storm
“We are the first generation that through its neglect could destroy the relationship between humans and the planet and perhaps the last generation that can prevent this”
(Lord Nicholas Stern, 2014), From Nicholas Stern, 2015, ‘Why are we waiting: The logic, urgency and promise of tackling climate change’, The MIT Press, Cambridge, Massachusetts
For most of our history the planet’s climate was relatively stable
"Our species (homo sapiens) is about 250,000 years old but our civilizations only emerged about 10,000 to 12,000 years ago, during the end of the last ice age during the Holocene period. For the last seven or eight thousand years temperature have been ‘remarkably stable, fluctuating in a range of plus or minus 1.5oC …” (Stern, 2014, and see also IPCC Fourth Assessment Report, 2007, Chapter 6).
The point of this observation is that a relatively stable climate has been important in the development and enormous growth of our human population during this period.
And living standards dramatically improved for more and more people
The industrial revolution in particular set in motion a huge improvement in the material wealth of Western Countries, in particular. The technology and social organization that emerged from the industrial revolution has had profound impacts across the planet, many of them good for humanity (increase in life expectancy, health care and mechanization of labour, for example). Of course industrialization has its costs (climate change is one), but the simple point is that few of us would prefer a pre-industrial life to the gains in human wellbeing over the last 200 years. We have much to be grateful for! But …
This has forced up the planet’s temperature
Global average surface temperatures have risen by 1oC from pre-industrial averages. Most of this increase is not from natural climate fluctuations but from the climate altering greenhouse gases we have been dumping, in increasing amounts, into the atmosphere. Small changes in the climate system have big impact
While 1oC might not seem like much, remember that the climate system is not the same as the weather. While weather can vary greatly in a single day (as the great New Zealand band (!) Crowded House observed in 1992), even minor changes to the climate system, measured in decades, can have a huge impact on the weather we experience.
If average global temperatures increase another 3oC to 4oC, then this is likely to increase land surface temperatures between 4 – 10oC. Melbourne, Australia, has already hit 46.4oC in 2009; imagine another 4-10 degrees on top of that, and heat waves that last considerably longer! 55,000 people died during the Russian heat wave of 2010 and 25% of crops failed (Stern, 2014).
Unprecedented storms and record bush fires
It doesn’t take much imagination to consider how this will impact the severity and frequency of catastrophic bush fires. During the 2013 NSW bush fires, two people died and 248 houses were destroyed. The prime minister at the time (Tony Abbott) stated that there was no evidence linking climate change to these fires.
He was right, strictly speaking, but since then a number of academic analyses have been published clearly linking the severity of these fires to climate change (i.e., a hotter world). While climate change did not ‘cause’ these fires, these studies show clearly that if we had not been pumping greenhouse gases into the atmosphere, then these storms would have been less likely to have occurred and significantly less severe in their impact.
The lesson is that a warming planet makes these events more likely and more dangerous than they would otherwise have been.
It’s not about global conspiracy
There have been a large number of books and articles published in the last 4-5 years looking at the climate denier ‘movement’. This well funded and (for the most part) coordinated assault on climate science strongly resembles the type of attack from the tobacco industry when clear evidence emerged about the links between smoking and various adverse health outcomes (including lung cancer).
One claim the critics make is not actually about the science of climate change, but is ideological; that is, climate change is really a front to enable the United Nations to set up a World Government, a socialist/communist plot to take away freedom from Americans (it is a peculiarly American phenomenon!). Thus, climate change gets redefined as a ‘global conspiracy’ of scientists wanting to set up a ’World Government’, and therefore they manipulate the data to ‘create’ a global problem. See Naomi Klein, ‘This Changes Everything: Capitalism versus the Climate’ for an interesting account of this conspiracy movement.
In any event, this is a ludicrous claim; how one could ever create a genuine conspiracy, co-opting thousands of independently minded scientists across dozens of countries to mislead the public shows that those making these claims have never actually worked in a research orientated University. Try herding cats; it is much easier! Nevertheless, this claim does recognise that climate change is a global issue and cannot be solved without the cooperation of all parts of the global community.
The term ‘atmospheric commons’ means that the atmosphere belongs of all members of the human community (and also to all species who depend on fresh air and a particular type of climate). It belongs to us all, yet we are treating it as a free place to dump our wastes (CO2, methane and other greenhouses gases). This ‘common resource’ does not have proper governance, a set of commonly agreed and enforceable rues around how we can treat it. The global conspiracy brigade understands that climate change will force us to create global rules, so they try to argue that climate change is not about the climate!
There are lots of examples where global rules were created to solve some global problems (lead in petrol, acid rain, CFCs, United Nations' Convention on International Trade in Endangered Species of Wild Fauna and Flora) but these have not led to a world government.
It’s not about money
Some folk, mostly anonymously on social media, claim that climate change theories are concocted by scientists so that they can get money for research and keep their jobs. I won’t dignify this with a serious response except to say there are many other challenges and issues that scientists can put their efforts into, all worthy of research funding, so why would they fabricate a set of false claims in the hope that they will get more money? This is a rhetorical question by the way! I have also worked professionally in the research-funding sector, and I know just how difficult it is to secure funding for even the most worthwhile projects.
It’s not about what you ‘believe’
Climate change is not a belief, like a belief in the ‘right’ to bear arms, in religious freedom or in democracy. These beliefs are just that, ideas about how the world should or should not be. They are not about how the world actually is. They might be really good ideas (or not), but they are the product of human minds. We can believe these things or not believe them. Our belief will not change the physics that makes our world go around.
Climate change is not a ‘belief’ in that sense above. It is a claim about how the world actually is, a claim that can be investigated to see if it is valid. Its truth or validity does not depend on ‘what we believe’ but rather on the evidence we find.
In other words, what is important is not our belief (the story in our heads about climate change), but the evidence that is ‘out there’, in the data and in the scientific models.
(NB: the notion of ‘truth’ is more complex than this brief explanation suggests; but it is helpful in thinking about the difference between a false belief (something that we believe, even passionately, but are factually wrong about, and justified belief, where the belief is a product of sound evidence. For a wonderful review of this, see ‘On being Certain; Believing you are right even when you are not’ by Neurologist Robert Burton.
Don’t you see, its Chemistry
CO2, and other greenhouse gases - the main ones are water vapor (H2O), methane (CH4), Nitrous Oxide (NO2), Ozone (O3), and Chlorofluorocarbons (CFCs) - are chemically altering the atmosphere. Regardless of what we wish to believe, this is the bottom line; we can’t mess with physics and chemistry. By the way, it is probably more accurate to say ‘Don't you see, its Physics!’. But that doesn't rhyme at all well. Science submits to poetry here!
The atmosphere is the very thin blanket of gases that cover the surface of the planet. It is about 100 km thick, which is pretty thin when compared with the circumference of the planet (just over 40,000 km). These gases are responsible for our climate because they trap heat from the sun. Without the atmosphere, the planet would heat up ferociously during the day (when the sun was hitting the surface) and then freeze like crazy at night as all the heat escapes into space. We couldn’t live here.
Our atmosphere enables the earth to have a relatively stable climate system. Almost all life lives inside this remarkably thin blanket. And we are now rapidly changing its chemical composition by adding CO2 and other greenhouse gases.
When Simon’s grandfather was born, CO2 levels were about 290 parts per million (ppm), a little above the average over at least the last 800,000 years. When Simon was born, CO2 was about 315 parts per million (ppm). When his kids were born, it was around 350 ppm. When his grand kids were born in 2015, it was over 400 ppm.
(Data source: https://data.giss.nasa.gov/modelforce/ghgases/Fig1A.ext.txt)
Carbon and our Discontents
In 2014 we added 1132 tons of CO2 to the atmosphere … every second
Since 1870, human activity, such as burning coal and oil, deforestation and agriculture, has emitted 1,996.9 Gigatons of CO2 (GtCO2). This does not include people breathing, just to be clear!
Total cumulative emissions from 1870 to 2014 were 400±20 GtC (1465 GtCO2) from fossil fuels and cement, and 145±50 GtC (549.6 GtCO2) from land use change. The total was 545±55 GtC.
Note the difference between tons of Carbon Dioxide (CO2) and tons of Carbon (C). CO2 weights 3.664 times the weight of C. So the cumulative emissions of Carbon is 545 GtC but expressed as CO2 it is 1996.88 GtCO2
A Gigaton is a billion tons of carbon, that is, 1000 million, or 1,000,000,000,
Also be aware that there are two versions of what a BILLION refers to. It can mean a Million Million (1,000,000,000,000) OR a Thousand Million (1,000,000,000). Science and economics usually now use the shorter version, what is called the ‘short scale’, i.e., 9 zeros. The UK changed to this in early 1970s). We use the short scale version here.
The visuals on the cumulative CO2 emissions were produced by Carbon Visuals
The original Global CO2 Visual used 2012 data and can be found here:
We updated the data to 2014, where of 35.7 GtCO2 emitted by human activity. The numbers were broken down as follows:
35,700,000,000 / 365 = 97,808,219.1781 Days
97808219.1781 / 24 = 4075342.46575 Hours
4075342.46575 / 60 = 67,922.37 Minutes
67,922.37 / 60 = 1132.07 Seconds
1132 GtCO2 Every second
Data on the 2014 Global Emissions can be found here:
Carbon Visuals image of Australia’s daily CO2 emissions can be found here:
The impacts from the CO2 we emit today will continue for the next thousand years
CO2 stays in the atmosphere for a very long time and continues to impact the climate long after we stop emitting it. This is why we must urgently reduce and halt further emissions.
“This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years”
If CO2 emission levels keep rising … and the level gets beyond 450 ppm CO2 the impacts that should be expected are irreversible dry-season rainfall reductions in several regions comparable to those of the “dust bowl” era and inexorable sea level rise. Warming ocean leads to irreversible global average sea level rise…. But add that to melting glaciers and ice sheets means sea level rise may be as high as several metres over the next millennium.
(Susan Solomon, et al, 2009, Irreversible climate change due to carbon dioxide emissions, Proceedings of the National Academy of Sciences of the United States of America (PNAS), Vol. 106 no. 6, 1704–1709)
A song for a warming planet
Written by Cellist Daniel Crawford, this piece takes the annual average global surface temperatures from when reliable records began (1880) till 2011, and translated each data point to a musical note. The notes start very low on the cello and get progressively higher and higher.
We have added an additional 3 years of temperature levels to this. For the musically inclined, the last note on the sheet is A (2012). We added the years, 2013, 2014, 2015, and 2016. The notes just keep on getting higher.
This tune asks the question a lot of people ask? What's so bad about a little bit of warming?
The problem is HEAT! HEAT is energy, and as the planet warms up, then the atmospheric energy increases. For example, when it is hotter, more evaporation takes place and this means there is more moisture in the atmosphere. In some places, particularly the tropics, this means more and heavier rain, causing increased flooding.
For example see this article on the 2017 floods in Northern NSW.
HEAT also means storm systems, again especially in the tropics, have more energy and therefore become more powerful than we have been used to. This means our homes and businesses are not designed to withstand such onslaughts. And if we keep adding HEAT to the climate system, these storms will only get bigger and more dangerous.
HEAT also means long-term drought in some places (especially Australia) and that means we can’t grow food in the same way. Drought is a very real risk to Australia and we are rolling the dice dangerously as we heat up the climate.
Finally, this is a useful explanation on the impacts of warmer!
Greenhouse Gases for the Masses
Video of annual average global temperatures
This graphic visualisation tracks the annual average global temperatures (in colour) from 1880 to 2011. It was produced by NASA.
For 800,000 CO2 in the atmosphere has not exceeded 290 ppm
For at least the last 800,000 years level of CO2 in the atmosphere was between 250 -290 ppm. From about 1850, these levels began to rise. (Australian Academy of Sciences, The Science of Climate Change, Questions and Answers, February, 2015)
The reason scientists know this is that they have figured out how to analyze the chemistry of bubbles of ancient air trapped in Antarctic ice. This gives them a good understanding of how carbon dioxide levels have varied in the atmosphere since that time. But they are currently less clear how to reconstruct carbon dioxide levels prior to 800,000 years ago.
It hit 400 ppm in 2015
In May 2015 the monthly global mean CO2 concentration was 400.94 ppm for the first time. See these links:
If you look at annual cycle of CO2, it gets high in the northern hemisphere winter and then drops back in summer. This is the normal cycle as trees shed their leaves in winter, adding to CO2 levels, then soaking up CO2 during the growth months of summer. This is how the planet breathes in and out. It’s just that each in and out breath takes 12 months! More CO2 is released in the northern hemisphere because there is more land mass and more forests. For a cool video of this cycle, one we also included in the show, see https://www.youtube.com/watch?v=x1SgmFa0r04
So how much CO2 have humans added to the atmosphere? Humans have emitted 365 billion tons of CO2 since the industrial revolution (World Meteorological Organisation; WMO Greenhouse Gas Bulletin No. 8, 19 November 2012)
The highest it has been for 15 million years
While difficult to be precise, scientists believe there is evidence that it is likely that the current level of CO2 has not been this high for 15 million years. See:
Also note that as CO2 builds up in the atmosphere, it results in a warming of both the land surface and the oceans. The last three decades have been successively warmer than any preceding decade since 1850
Put very simply, things are warming up.
And if you are wondering about the so-called ‘pause’ in warming, this has been well investigated and explained. Click here for a simpler, less technical explanation
2015 was the hottest since records began
This measures the global average surface temperature from Jan 2015 - Dec 2015. The NASA link above uses a base line of the average global surface temperature from 1950 - 1980. Compared with this average, the 2015 record was 0.87°C above that average. Since 1880, when records began, it has just reached 1.0°C above the 1880 temperature.
Some places were colder than average, but the planet as a whole averaged higher temperatures than any other year on record. This is why looking at the weather (‘Hey, its been a cold winter here in my town!’) does not tell us what the overall climate system is doing. We need the global data for that!
January, February and March 2016 smashed the temperature records for those months.
Our Hotter World ...
Is killing the Great barrier Reef
A warmer planet means warmer sea temperatures. Coral reefs have a low tolerance for increasing ocean temperatures, and as a result they risk serious bleaching and, ultimately, death from rising sea temperatures.
They are also sensitive to CO2 levels in the ocean (called ocean acidification) and because the oceans soak up significant levels of CO2, they are getting more acidic and recent research is showing this poses risks to the ongoing survival of coral reefs.
Other damaging impacts include sea level rise (which is not uniform across the planet and therefore affects some places more than others).
Even though the Australian Government has announced a welcome package of measures to protect the Great Barrier Reef, it does not adequately address global temperature rise. Therefore, in the absence of dramatic global efforts to reduce greenhouse gas emissions, the Great Barrier Reef will be lost or permanently degraded and reduced. This is a direct consequence of our dumping of greenhouse gases into our atmospheric commons. A recent World Wildlife Fund report on the state of the oceans stated there is a possibility of losing all coral reefs by 2050 due to increasing temperatures and ocean acidification.
A useful summary with links to some of the research is found here.
The most recent IPCC summary on the oceans is here
Last time there was this much carbon in the atmosphere, modern humans did not exist The world’s oceans were 30 metres higher than today and global average surface temperature was 6 degrees warmer than now
Our world is changing and there is much that will be lost
Changes to our climate are already changing our world. There is evidence that more people are dying as a result of heat waves made more severe because of global warming (and interestingly, a reduction in cold related deaths as well) http://ar5-syr.ipcc.ch/ Pg. 53. Bush fires are now more severe in both Australia and California, the California drought, the worst on record, is being impacted by several seasons of very poor snowfall, an impact of increased global temperatures.
Seal levels are rising, something scientists are now clear about, (http://ar5-syr.ipcc.ch/ Pg. 53) and storm surges, such as with Hurricane Sandy having devastating impact on the affected communities.
Disasters such as long-term drought and resulting massive crop failure drive refugee crises. The Syrian civil war has resulted in over 12 million refugees having to flee their homes. While climate change did not cause the war, the long-term drought in Syria destabilised communities, making a much more vulnerable population. A research paper published in March 2015, found: “There is evidence that the 2007−2010 drought contributed to the conflict in Syria. It was the worst drought in the instrumental record, causing widespread crop failure and a mass migration of farming families to urban centers” ‘Climate change in the Fertile Crescent and implications of the recent Syrian drought’.
The authors say that climate change, while not causing the drought, made it 2-3 times worse that it would have been if we had not already heating up the climate in the region. See this Guardian report for an easier read on the same issue:
While there is still some controversy about the extent to which climate change is currently causing climate refugees (see Eric Lambin’s 2012 An Ecology of Happiness, Chapter 7: Environmental Conflicts), nevertheless, as the world warms up, as more communities suffer drought and food shortages, this can only increase the tension and conflicts that already exist. More people will for forced to flee their homes. Where will they go in a world of 8-9 billion under major climate stress?