Climate change

Upsala Glacier
Upsala Glacier, Argentina, once the biggest in South America – 1928 and 2004
Image from Transition Initiatives Primer


Are we causing climate change? In 2024 there can be very little doubt that human activities are the primary cause of climate change and its associated problems. The main question now that we are a quarter of the way through the twenty-first century is: why are we not doing more to reduce the emissions that are causing a disastrous level of climate change?

In the many years since I started this page the evidence for anthropogenic climate change and the related problems of ocean acidification, ocean warming and sea level rise has been steadily increasing. One year after another is either the hottest on record or close to it.

And then there are the millions of people killed each year by air pollution from the burning of the billions of tonnes fossil fuels, particularly coal, that are among the main causes of climate change.

The cost of dealing with climate change will be far less than the cost of not dealing with it.

Those people who want the facts about climate change should look for reliable information in the science press (journals such as New Scientist and Scientific American are understandable by intelligent laymen) rather than the popular press. (The Murdoch press in particularly often publishes material denying climate science.) While much of the popular media suggests that the climate change question is not settled, the great majority of climate scientists believe that mankind is largely driving climate change.

In 2006 the Royal Society, probably the most prestigious, certainly the most venerable, scientific society in the world, wrote to ExxonMobil asking them to stop funding a disinformation campaign on climate change.

James Lawrence Powell posted on DESMOGBLOG about a search he did of the peer-reviewed climate change science. Of a total 13 950 articles he found that only 24 rejected global warming.

This page was created 2006/12/01 and last edited 2024/03/21
If you find an error on any of these pages you will be doing me a favour by pointing it out so that I can correct it.

Contact: David K. Clarke – ©

What are the alternatives and the consequences?

One thing we can do is look at the consequences of action or inaction.

We are causing climate change
We are not causing climate change
We take strong action
We avoid the worst consequences of climate change.

Big money will have to be redirected. Contrary to the claims of many of those who resist action the financial impacts will likely be more positive than negative because of the expanding new industries required.

We move from unsustainable technologies to sustainable before we would be forced to for other reasons.

Big money will have to be redirected.

We do nothing
Global disaster!
  • Huge loss of species and damage to our environment;
  • Sea level will rise by several metres;
  • Great areas of the Earth will become uninhabitable or at least will no longer be able to support the populations that they now have because of desertification, flooding or heat;
  • Rainfalls will be much less in some places, more in other places;
  • Storms, including hurricanes, will become more violent;
  • Hail storms with very large hail stones will become more common and more damaging;
  • Wildfires will become more common and more ferocious; fire danger seasons will become longer;
  • Changes such as the above will likely cause mass migrations and wars;
  • The acidity of the oceans will increase with possibly disastrous results to fishing industries and to other ocean organisms;
  • Ocean temperatures will continue to rise, causing, among other things, loss of many coral reefs;
  • Ocean currents might change;
  • It is possible that the oceans could become anoxic.
Many of these things have already happened; they will get worse.

I have written more about the probable effects of climate change in Disasters compared.

No problem

We will still have to change away from fossil fuels eventually, simply because they will not last for ever.

Why accept that humanity is causing climate change?
(Climate change caused by humanity is called anthropogenic climate change: ACC)

First, the science:
  • About 99% of papers published in peer-reviewed climate journals accept the fact of ACC;
  • The vast majority of climate scientists accept the reality of ACC;
  • I doubt there is any scientific organisation that has any interest in climate, anywhere in the world, that does not accept ACC.
In addition:
  • Almost every national government in the world accepts the reality of ACC;
  • I doubt there is any respectable university anywhere in the world that teaches that ACC is not true;
  • The world's reinsurance industry is factoring-in increasing frequency and severity of natural disasters to the cost of insurance coverage;
  • The world's mainstream religions are pushing for serious action to slow climate change.
For more up-to-date information and more reasons to accept climate change is really happening and is really caused by humanity go to Why accept climate science.

The hottest years on record

The sixteen warmest years (1880-2015)
Hottest 16 years
Image credit NOAA (National Oceanic and Atmospheric Administration, USA)
As of early 2016 the sixteen hottest years in the history of reliable global temperature data have all occurred since 1998 – as shown in the table on the right.

This was reported by NOAA (USA National Oceanic and Atmospheric Authority) in its 'Global Analysis – Annual 2015'.

Update, 2024

Climate Change Guide reported in 2023 that the hottest 10 years on record were:
  1. 2016
  2. 2020
  3. 2019
  4. 2017
  5. 2015
  6. 2022 (tied with 2015)
  7. 2018
  8. 2021 (tied with 2018)
  9. 2014
  10. 2010
Later NASA stated that 2023 itself was the warmest year on record.

Seven Eight reasons why climate change is even worse than we thought

Billion $ disasters
The figures used in the graph were adjusted for inflation
Graph credit New York Times
The possibility of Man causing climate change has been recognised
for well over a century.
Svante Arrhenius recognised the possibility of anthropogenic
climate change in 1896.
CC warning

From New Scientist, November 2012

  1. The thick sea ice in the Arctic Ocean was not expected to melt until the end of the century. If current trends continue, summer ice could be gone in a decade or two.
  2. We knew global warming was going to make the weather more extreme. But it's becoming even more extreme than anyone predicted.
  3. Global warming was expected to boost food production. Instead, food prices are soaring as the effects of extreme weather kick in.
  4. Greenland's rapid loss of ice mean we're in for a rise of at least 1 metre by 2100, and possibly much more.
  5. The planet currently absorbs half our CO2 emissions. All the signs are it won't for much longer.
  6. If we stopped emitting CO2 tomorrow, we might be able to avoid climate disaster. In fact we are still increasing emissions.
  7. If the worst climate predictions are realised, vast swathes of the globe could become too hot for humans to survive.

  8. (From the New York Times, not from the New Scientist article) As the graph on the right is showing, disasters that have been called natural are becoming more common (and more severe) due to climate change. We could ask, should they continue to be called 'natural disasters' in the future?
I've written on how the burning of fossil fuels is a huge environmental disaster more recently (2017) on another page on this site.

The precautionary principle

When one is faced with two possible paths and cannot be sure which is the best it is wise to look at probable consequences. If one path leads to possible disaster and the other does not, then we plainly should be very wary about taking the former.

Cost of climate change

The cost of greatly reducing our reliance on fossil fuels will be high, but the cost of the damage done by run-away climate change will be much higher; it will be incalculable because how does one place a monetary value on things like biodiversity, rainfall and this world that we love?

Will spending on fighting climate change harm economies?

At the beginning of World War Two the world's economies were in poor shape, we were coming out of the Great Depression. Big money had then to be spent on building weapons and the machinery that was needed to fight the war (just as now big money needs to be spent on fighting climate change). The effect then was not a decline in economic activity, but a big rise in economic activity. If the world takes on climate change the result will more likely be a boost in economic health rather than a decline.

Balanced media coverage

Some reporters like 'balanced' coverage so much that when they have a report from a well informed climate specialist they then look around for someone to give a contrary view. If the only people to provide that view are ill-informed or those with reasons of their own to avoid the facts a responsible reporter would not call on them, but in practice many reporters are willing to accept them with their unjustified opinions. There are several possible reasons for this seeking of balance, some of them good, some not. Media consumers need to be aware of this tendency.

I have written more on this subject on a page titled Poor Journalism Has Many Victims.

This section
changed 2009/12/24

Is climate change happening?

Thirty years ago there was some doubt that we were seeing consistent and wide-spread changes to the climate; now even the 'climate change skeptics' agree that the climate is changing, the arguments are to do with the causes.

Global temperatures


Positive feedback

Climate change feedback is changes – caused by anthropogenic climate change – that either enhance or reduce the greenhouse effect. Positive feedbacks are those changes that amplify the greenhouse effect and climate change.

Some important forms of positive feedback for the greenhouse effect are:

  • Melting of arctic and antarctic sea-ice, antarctic ice shelves, and mountain ice and snow exposes the darker rock, soil, or sea beneath; which then absorb more of the Sun's heat and further warm the Earth. (Ice and snow, being bright, reflect light and heat back into space.)
  • Melting of arctic permafrost releases methane, which is a strong greenhouse gas and hence causes more warming.
  • There are large quantities of solid 'ices' called methane clathrates on the ocean floor. If the oceans warm sufficiently these will be released into the atmosphere.
  • As the climate warms the air can hold more water vapour, which is a strong greenhouse gas.
These feedbacks are suspected of causing global temperature rises of between 5 and 8°C about 55 million years ago during the Paleocene-Eocene Thermal Maximum.

Causes of anthropogenic climate change

Anthropogenic: Caused by humanity
  • Increased atmospheric carbon dioxide due to massive burning of carbon-containing fossil fues: petroleum, natural gas, coal; and other causes such as changes to land use and clearing of forest;
  • Increased atmospheric methane from ruminant animals, rice growing, and other sources;
  • Increases in other greenhouse gasses such as nitrous oxide, chlorofluorocarbons and nitrogen trifluoride;

The symptoms of climate change

Not directly related to climate, but due to one of the causes of anthropogenic climate change, the rise in carbon dioxide levels:
  • Acidification of the oceans;
  • Increasing difficulty for aquatic organisms in constructing and maintaining their shells.

Have these things happened before?
If so, how long ago?

Carbon dioxide levels
"The extension of the Vostok CO2 record [which covers the period 417 160 to 2342 years ago] shows the present-day levels of CO2 are unprecedented during the past 420 kyr." (420 000 years) From CDIAC, Carbon Dioxide Information Analysis Center, USA.

The rise in average global temperatures of the last hundred years is unprecidented since at least the end of the last ice age, about 10 000 years ago.

Sea level rise
Australia's CSIRO stated that "The global average sea level rose by close to 20 centimetres between 1870 and 2007." and "Sea levels rose at an average of 1.7 millimetres per year during the 20th century, and 3.4 millimetres per year from 1993 to 2007." (Relevant link no longer available.)
The publication referenced below states that: "The estimated rate of sea-level rise from anthropogenic climate change from 1910 to 1990 (from modelling studies of thermal expansion, glaciers and ice-sheets) ranges from 0.3 to 0.8 mm/yr. It is very likely that 20th century warming has contributed significantly to the observed sea level rise, through thermal expansion of sea water and widespread loss of land ice." These rates of rise are greater than those recorded over the past 6000 years and much greater than over the past 3000 years. (Published on ePIC (electronic Publication Information Center), the official repository for publications and presentations of Alfred Wegener Institute for Polar and Marine Research. See here.)

Coral reef 'bleaching'
It seems that the present reef-coral species have been dominant for the last several million years. Before that there were species that could handle higher temperatures than the present ones, but they have become extinct. An interesting source on the subject is Global Coral, particularly their page " REEF BLEACHING AND SEA SURFACE TEMPERATURE.html".

Arctic sea ice
So far as I have been able to find out, the evidence suggests that the Arctic Ocean has not been free of ice in at least the past 100 000 years. See

Greenland ice sheet
The ice in the Greenland ice sheet is up to 110 000 years old, but there has been an ice sheet there for around 2.6 million years. (The ice very slowly flows toward the sea and is replaced by new snow-fall.) (From Wikipedia)
Science Daily reported (2009/11/13) that the Greenland ice sheet is losing mass at an accelerating rate and has caused 5mm of rise in sea level from 2000 to 2010.

Break up of ice shelves
Wikipedia states that the Larsen B ice shelf (of the Antarctic Peninsula) "was stable for up to 12 000 years". It collapsed and broke up from January to March 2002. It was 3250km2 in area and 220m thick. Other Antarctic ice shelves have also broken up.

Retreat of mountain glaciers
Most of today's mountain glaciers would, I believe, have been in place since before the last ice age, which finised around 12 000 years ago. Water Encyclopedia states that ice first started to accumulate on Mount Kilimanjaro (on the equator in Africa) nearly 12 000 years ago (presumably as precipitation increased following the decline of the ice age) and Kilimanjaro's glaciers will probably have melted by the year 2020.

Melting of permafrost
The arctic permafrost is likely to have been in place for a similar time as the arctic sea ice, ie. 100 000. Much carbon (including in methane) is locked up in permafrost, and will be released into the environment if the permafrost melts. See CSIRO: Permafrost melt poses major climate change threat.

Release of methane from permafrost
Under an article titled Scientists discover huge seabed methane leak, ABC On-line news reported that "current average methane concentrations in the Arctic are the highest in 400,000 years". Methane, of course, is a strong greenhouse gas.

Ocean acidification
I have written on ocean acidification at more length on another page on this site.
Wikipedia states that "Between 1751 and 1994 surface ocean pH is estimated to have decreased from approximately 8.179 to 8.104". The Royal Society produced a paper (Ocean acidification due to increasing atmospheric carbon dioxide) in which they state that atmospheric CO2 concentrations have not been as high as now in the past 420 000 years. This paper also stated that "the fastest natural changes that we are sure about are those occuring at the ends of the recent ice ages, when CO2 rose about 80ppm in the space of 6000 years.

Reduced rainfall
Average rainfalls vary with time and place, but average rainfalls have declined unusually in a number of parts of the world in recent decades. The drought in the Murray-Darling Basin is unprecedented in Australian history.

Major extinction event
It is likely that the number of species extinctions due to anthropogenic climate change and ocean acidification will be greater than all but about three on the geologic record of the past 500 million years.

Loss of Eucalyptus macrorhyncha
The pocket of E macrorhyncha refered to above (in the section 'The symptoms of climate change') would have been in place since at least the end of the last ice age. The loss of these trees is related to the decline in rainfalls shown on the graph above.

Sea level rise

This section added
The world's sea levels are rising and the rise is caused by climate change. As reported by NASA:
"Sea level rise is caused primarily by two factors related to global warming: the added water from melting ice sheets and glaciers and the expansion of seawater as it warms."

Ocean currents are becoming more energetic

In 2021/04/23 a group of researchers published an article in The Conversation headlined "Satellites reveal ocean currents are getting stronger, with potentially significant implications for climate change". The research had been published in the journal Nature Climate Change.
The NASA page showed that, using data from coastal tide gauges, sea levels had risen by about 240mm between 1880 and 2013. In the period from 1993 to 2020 sea level measurements taken by satellites showed good agreement with those from tide gauges.

Australia's CSIRO's page on Sea Level, Waves and Coastal Extremes showed the same as the NASA page.

The rate of rise has increased from about 1995. NASA stated that:

"The rate of sea level rise in the satellite [from 1993 to the present] era has risen from about 2.5 millimeters per year in the 1990s to about 3.4 millimeters per year today."
Sea level rise will hugely impact many of the world's most highly populated areas such as the deltas of the rivers Nile, Ganges/Brahmaputra, Red River and Mekong. Some great cities such as New York will also be facing major damage.

Science proves nothing

How often do we read something like "the link between carbon dioxide and climate change has not been conclusively proven"? Or "it has never been proven that Mankind is causing climate change"?

There are two things that need to be said about this sort of statement.

  1. The world cannot afford to wait until there is absolutely no doubt about how disastrous climate change (and ocean acidification) is going to be or about the exact causes of climate change. The problems are too serious, we have to act on strong evidence and not hope for conclusive proof;
  2. Science does not prove anything. Science tells us which theories fit the evidence and how well they fit the evidence. Science can never prove that one thing causes another; it just doesn't work that way. For example, Newtonian mechanics were, and still are, very valuable; but they were superseded by Einsteinian relativity. In its turn, relativity fits the observed facts better than Newtonian mechanics, but relativity has not, and never will be proven to be absolutely correct.
What science has done is to show us that the changes that Mankind is making to the atmosphere is very likely to be causing the climate change (and ocean acidification) that we are observing and that if we do not make serious changes both these problems will get much worse.

Comparing the arguments

Who are the experts

When we have difficulty deciding which side of an argument has the most validity, and we feel we do not have the needed expertise ourselves to make the decision unaided, we often look for advice from an expert.

This is called trusting to "ex cathedra" statements – trusting statements because of their source. There is some risk in this because the experts in whom we trust can be wrong just us we ourselves can be wrong, but in a complex issue such as climate change what else can we do?

Plainly, if we pick the right experts our information is more likely to be good. If you wanted information on visiting Vietnam you wouldn't ask someone who had never gone outside of Australia. If you wanted advice on gardening you wouldn't ask someone who had never planted a seed in his life. It follows that if you want information on climate change you should look to a climatologist, a scientist who specialised in the study of climate, or even better, someone who specialised in the climate change branch of climatology; you wouldn't ask a geologist or a medical doctor.

Unfortunately there seems a common tendency for people to believe that any scientist is an expert on all fields of science, even to believe that anybody who is expert in any field at all is expert in all fields. Some of the 'experts' are very willing to go along with this error – it suits their ideas of their own importance.

What is the science telling us?

According to NASA "Multiple studies published in peer-reviewed scientific journals show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities."

And for those who deny the science, there are many other reasons too.

There's about as much doubt about global warming as there is about whether the Earth is flat or round.

Opinions of scientists in the climate science field; a consensus

Is it caused by Man?
Graphic credit: The Berkeley Blog
The graph on the right shows that the vast majority of climate and earth scientists accept that global warming is largely caused by Mankind.

Published in Environment Research Letters, Cook, Nuccitelli, Green, Richardson, Winkler, Painting, Way, Jacobs and Skuce examined 11 944 abstracts and found:

"that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming."

Other papers on the consensus between climate scientists have been written by Oreskes, 2004; Heima; and Anderegg, 2010.

Also see Wikipedia


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North Atlantic cooling

World temperatures
Image credit NOAA, via Washington Post
The image on the right was published in the Washington Post in September 2015.

Put simply, the red and pink areas show the parts of the world that are warming and the blue shows those few areas that are cooling.

Apart from the obvious warming of most of the planet the cooling area in the North Atlantic is of particular concern. It suggests that the normal circulation of the North Atlantic Ocean may be slowing down due to the release of huge volumes of fresh melt-water from the Greenland icecap.

The normal circulation, or the Atlantic Meridional Overturning Circulation, (AMOC) is explained in The Encyclopedia of Earth.

The AMOC is of huge importance because for thousands of years it has been responsible for warming Europe. Without the AMOC much of Europe would be so cold as to be a very different place to what it is at present.

Climate change denial

Wikipedia has an article on climate change denial, and there is an excellent piece by George Marshal on the psychology of climate change denial on Eco Globe. Marshal wrote:
"In the case of climate change, then, we can intellectually accept the evidence of climate change, but we find it extremely hard to accept our responsibility for a crime of such enormity."
Several independent surveys have shown that 97 out of 100 climate experts agree humans are causing global warming.

However, movements that deny a scientific consensus have always sought to cast doubt on the fact that a consensus exists. One technique is the use of fake experts, citing scientists who have little to no expertise in the particular field of science.

Who is funding climate change denial?

Scientific American carried an article on 2013/12/23 about a study into this question by Robert Brulle of Drexel University. Not surprisingly Brulle found that the money was coming from wealthy people and organisations who were pushing 'ultra-free-market ideas'; in other words, profit at whatever cost.

Read the Scientific American article or follow that to the original for more information.

In Australia, the coal industry, and the mining industry in general, is enormously wealthy and stands to lose a huge amount if we move to a low-carbon future. People like Gina Rinehart, wealthiest person in Australia and wealthiest woman in the world, are funding a highly effective misinformation campaign.

A climate science denialist: 'Lord' Christopher Monckton

This man is something of a hero to the climate science denialists. He has had several speaking tours of my country, Australia. He was invited to Ballarat by a prominent wind power opponent, Senator John Madigan and I believe he has been interviewed by another locally well known climate science denier, radio shock-jock, Alan Jones.

The quote below is from Right Wing Watch, 2015/01/13, and had the very appropriate headline: Watch Out: Islam, Socialism, Environmentalism Uniting To Kill Us All.

'Lord' Monckton said:

"What they want to do is reduce the population not by one billion but to one billion," he said. "It's now 7.2 billion, they want to cut the population by 6.2 billion.... It's a conspiracy."

"They are ganging up together, the totalitarians, Islam and socialism and environmentalism, worldwide, getting into bed together to destroy as many of the world's population as they can," he added.
I leave it to the reader to decide how seriously this man can be taken.

Skeptical Science has an informative piece on 'Lord' Monckton's misinformation.

Ethics of climate change

If you went to a birthday party with six other people, would you eat half of the birthday cake?

Most people would consider such behaviour to be reprehensible. Yet that is what most Australians and USians are doing in regard to greenhouse gasses, the cause of anthropogenic (man-made) climate change.

When you drive a car that is bigger than you need you are being like the person who eats half the birthday cake. Driving a car at all is probably unsustainable.

Clare Valley, South Australia
How will this landscape change in the next fifty years?
Next time you go for a walk and look at a beautiful rural scene consider that in fifty or perhaps less years that scene will have changed due to climate change; the mix of vegetation will be different, probably many exotic plants will dominate the mix because the plants that you are looking at will no longer suit the conditions. Consider also how big a share of the blame for the change you will have to bare because of your present lifestyle.

I love the part of the world I live in and it saddens me to think that my countrymen in particular (Australians) are dumping so much greenhouse gas into the atmosphere that the landscapes I see around me will be forced to change, quite probably to change out of recognition. And the great majority of my countrymen don't seem to care enough to take action.

We have not yet learned, at a personal level, that the Earth's atmosphere can only handle a limited amount of greenhouse gasses without terrible damage; damage that can not be repaired in decades or even in centuries, damage that can never be repaired. Every one of us has a responsibility to limit his/her greenhouse gas production level to something that the Earth can handle. This is a lesson that we need to learn quickly, but, it seems, many of us are not learning at all.


Biggest global-health threat of 21st century

In May 2009 University College London and The Lancet jointly published a report calling climate change the biggest global-health threat of the 21st century.

Lead author Professor Anthony Costello (UCL Institute for Global Health) said that failure to act will result in an intergenerational injustice, with our children and grandchildren scorning our generation for ignoring the climate change threat – with moral outrage similar to how we today look back on those who brought in and did nothing to stop slavery.

In Australia we are learning that our water supply is very limited and that each of us must use it carefully if there is to be enough to go around for all. The problem with the atmosphere is similar, it can handle a limited amount of pollution; we must work out the total that it can handle, divide that by six billion, then limit the amount that each of us places in the atmosphere to no more than this amount.

Long ago there were few people on the Earth and the amount of land that each tribe could roam over must have seemed limitless. As the number of people increased, tribes had to learn that the land wasn't limitless, on the edge of 'their' land there were other tribes who had similar demands on the land. They would have gradually learned that if they wanted to avoid conflict they had to share the available land with their neighbours.

In the modern world we have come to rely on our governments to handle questions such as land boundaries (between individuals and between nations) and sharing the limited amount of available water. We cannot rely on our governments to protect our atmosphere and our climate from our actions. We must, ourselves, set examples and pressure other citizens to cut down on their greenhouse gas production. We need to make greenhouse irresponsibility a shaming matter. Our governments will not act until they perceive that the great majority of voters are serious about wanting action. We don't have the luxury of the necessary time to wait for our governments to getting around to acting.
Clare Valley, South Australia
How will this landscape change in the next fifty years?

There are two nations who's people produce much more than the average amounts of greenhouse gasses, Australia and the USA. The governments of these same two nations have so far refused to place any substantial limits on the activities of their people and their industries. Australia and the USA are culpable on two counts, they are producing more greenhouse gasses than any other nations (considering population sizes) and they are doing less about controlling their emissions than any of the other major greenhouse gas emitting nations. As both of these nations are democracies the world will rightly hold, not just the governments of the nations, but their people responsible for their selfish use of the atmosphere and the damage that they are doing to the world's climates. (For some figures on the degree of culpability see Australia and climate change responsibility.) Both peoples voted the culpable governments into power full well knowing that they would not accept their ethical responsibilities concerning the atmosphere. (This is the main reason that I am ashamed to be Australian.)

However, as alluded to above, people have become used to their governments handling the fair sharing of limited resources, so you would have to say that Prime Minister John Howard of Australia and President George W. Bush of the USA are the greatest greenhouse criminals on the Earth. They have demonstrated that they are without ethical principles on this, the greatest threat facing the Earth in the twenty-first century. By considering only the short-term good of some of their nation's industries they are taking away the Earth's future more than any other national leaders. In the future all of us in the West today will be held responsible for the colossal damage that we are now doing to the planet, but these two men will deserve a greater part of the blame than any other individuals. (Also see the failings and crimes of Australian governments.)

Prime Minister Kevin Rudd has proved to be almost as disappointing as Howard on greenhouse action; President Obama seems to be making a good effort, whether he can get Congress and the US Senate to support strong action remains to be seen (early January 2010).

Psychology of climate change


How do people react to different problems?

This depends on several things:
  • How near to me is the problem?
  • How urgent is it that the problem be fixed right now?
  • On a global scale, how important is the problem?
ProblemProximityUrgencyGlobal importanceLikely response
Burst water pipeMy own houseVery highVery low Immediate, determined
Climate changeWorld-wideSerious action within a decade It's the future of the planetToo hard, too big, not going to affect me in the near future, someone else must fix it; or denial.
Scientific American in January 2008 published an article describing how the USA could develop solar power stations to generate 69% of its electricity and 35% of its total energy by 2050. The authors estimate that this would cost $420 billion dollars in subsidies; the money would have to be spent by 2020, after that date the growth in solar power would be self-sustaining.

$420 billion is a lot of money. It's very hard to imagine the US administration deciding to spend that much to significantly reduce the country's greenhouse gas production rates.

In September 2008 President George W. Bush is pushing for Congress to release $700 billion dollars to bail-out big American financial institutions. Financial experts agree that the $700 billion will not fix the overall US debt problem, but it might stop an immediate lock-up of the financial system.

The worst that could result from not spending the $700 billion – and might result even if it is spent – is that the USA will fall into a depression that could last four or five years (in which case the rest of the world will probably go into a recession for a similar period). The worst that could happen if the US doesn't significantly reduce its greenhouse gas production rates is almost unimaginable environmental disaster that will cause not only financial collapse but also billions of deaths.

Since then President Obama has committed similar amounts of money toward fixing the 'economic meltdown'.

Why is the US administration willing to spend big to try to fix the financial problem, but not willing to spend big to try to fix the much more serious environmental problem? Neither is sure to solve the problem; but $420 billion, spent wisely over a couple of decades, would certainly go a long way toward reducing the US's terrible level of greenhouse gas production.

I am not a psychologist, but the answer seems to be that the one problem is immediate and the other is several decades away; we have not evolved to take seriously any threat that is so far in the future – we have evolved to react quickly to threats that we see in the near future. The trillion dollar bail-outs of the US financial system together with the US administration's failure to act on the much more serious greenhouse has suggested that psychology is of fundamental importance in humanity's response to the latter. One wonders why psychologists don't seem to have been vocal on the greenhouse/climate change problem?

It is a great pity that humanity is not able to make decisions on such important matters based more or rationality and less on emotion.

George Marshal on psychology of climate change denial

The following is extracted from a talk by George Marshal, Executive Director, Climate Outreach Information Network, Oxford UK
"Psychology of Climate Change"

Denial strategies specific to Climate Change

Metaphor of displaced commitmentI protect the environment in other ways
Condemn the accuserYou have no right to challenge me
Denial of responsibilityI am not the main cause of this problem
Rejection of blameI have done nothing wrong
IgnoranceI didn't know
PowerlessnessI can't make any difference
Fabricated constraintsThere are too many impediments
After the floodSociety is corrupt
ComfortIt is too difficult for me to change my behaviour
Source: S. Stoll-Kleemann, Tim O'Riordan, Carlo C. Jaeger, The psychology of denial concerning climate mitigation measures: evidence from Swiss focus groups, Global Environmental Change, 11 (2001) 107-117

Our response to climate change is out of proportion to the threat and urgency of the problem.

This lack of response cannot be satisfactorily explained as a deficit of information or as a temporary failure in the political and economic system and is not related to an individual's capacity to effect change.

We can observe a profound psychological disconnection between what people know about climate change and what people do about climate change

Failure of the "risk thermostat"

Our response is strongest to threats that are: Climate change is:
With historical precedentUnprecedented
ImmediateDrawn out
With simple causalityWith complex causality
Caused by another 'tribe'Caused by all of us
And have direct personal impactsAnd has unpredictable and indirect personal impacts

How do we move forward?

We recognise that information alone cannot produce change.
We openly recognise the tendency to denial.
We encourage emotional responses and "whistle blowers".
We develop a culture of engagement that is visible, immediate, and urgent.
As individuals we act with integrity and clarity.


Emissions per capita
The graph on the right was extracted from the World Inequality Report 2022 page 19. It is one of two that cover the major global regions.

On this graph each person in the top 10% in wealth in North America produces, an average, 73 tonnes of CO2 equivalent per annum while the bottom 50% in South and South-East Asia each produce only 1 tonne. (The second graph - not shown here - records that the bottom 50% in Sub-Saharan Africa each, on average, produce only 0.5 tonnes per annum.)

Putting this another way, a wealthy person in North America is responsible for about 73 times the emissions of a poor person in South and South-East Asia and about 150 times the emissions of a poor person in Sub-Saharan Africa.

Also see my page on Wealth and environment.

Loss of mangroves

As the sea levels rise coastal mangroves will be flooded. During the many past sea level changes in the world as it was, this would not have been a great problem to the mangroves; they would have gradually 'migrated' to higher ground with the rising sea levels. In much of the world as it is the mangroves will not be able to migrate, humans will have taken over the land into which the mangroves will need to move. They will be killed by flooding on the low ground and unable to advance into higher ground.

Mangroves and mangrove swamps have been shown to be very valuable as nursery grounds for many marine species. Loss of many of the world's mangroves will have far reaching environmental effects.

I suspect the synergies of the changes that are happening to the earth due to climate change will surprise us.

Climate change was a factor in starting the Syrian civil war

For years it has been predicted that the water shortages and droughts that climate change makes more likely will cause displacement of peoples and civil conflict. Research by Colin P. Kelleya, Shahrzad Mohtadib, Mark A. Canec, Richard Seagerc and Yochanan Kushnir published in the Proceedings of the National Academy of Sciences of the USA suggests that climate change was a factor in starting the Syrian civil war that caused the displacement of millions of people and the deaths of many thousands.

Carbon dioxide (CO2) in atmosphere and blood

There is natural CO2 in your blood just as there is natural CO2 in the atmosphere. If the amount of CO2 in your blood increased as much as the atmospheric CO2 has increased since industrialisation you'd have a serious health problem.

Normal blood levels (measured as bicarbonate) are 23-30mEq/L; atmospheric CO2 has gone from 280-400ppm in 200 years, an increase of 43%. A 43% increase in blood CO2 levels would take it to 33-43mEq/L; well outside of normal levels. (More on CO2 and blood.)

Air pollution caused by burning fossil fuels

The World Health Organisation (WHO) estimated in a report dated 2012 that air pollution causes seven million deaths each year; that's one in eight of total global deaths. Much of this, both indoor and outdoor air pollution, is due to burning coal as a fuel (see Killer Coal) while the exhaust of vehicles, especially diesel vehicles, also causes serious damage.

Fossil fuel air pollution responsible for 1 in 5 deaths worldwide, page dated 2021/02/09. Research led by Harvard University in collaboration with University College London, the University of Birmingham and the University of Leicester has been published in the journal Environmental Research.

Killer hail

On 2018/10/16 the ABC reported that a "Hail storm kills 400 kangaroos and 150 goats on properties in far-west New South Wales".

Coincidentally, less than a month earlier, 2018/09/20, Samuel Childs had written in The Conversation about a "Destructive 2018 hail season [in the USA being] a sign of things to come". Data published on Mr Childs' article showed that hail storms in which there were exceptionally large hail stones were becoming more frequent. The records indicated that both hail stones greater than 50mm and greater than 75mm were becoming more common. Climate science indicated that this was to be expected with climate change and the consequent increasing prevalence of violent storms.

Big hailstones are becoming more common

Samuel Childs wrote a piece for The Conversation on 2018/09/20 titled "Destructive 2018 hail season a sign of things to come".

Data published on Mr Childs' article showed that hail storms in which there were exceptionally large hail stones were becoming more frequent. The records indicated that both hail stones greater than 50mm and greater than 75mm were becoming more common. Climate science indicated that this was to be expected with climate change and the consequent increasing prevalence of violent storms.

Hail and solar panels

Large hailstones can damage solar panels. I have written a page on this elsewhere on this site.

Marine life is fleeing the equator because they can't stand the heat

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The oceans at the equator are becoming so hot that marine life is moving away. See the article in The Conversation: "Marine life is fleeing the equator to cooler waters. History tells us this could trigger a mass extinction event." Published 2021/04/08.

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Carbon capture and storage (CCS)

CCS has been a great hope of the fossil fuel industry. The proponents have claimed that they could dig up (or pump up) their fossil fuels, burn them and pump the resulting carbon dioxide back underground.

CCS has been tried in many places, in most it has completely failed. It is a theoretical possibility but an economic failure; fossil fuel energy with CCS is much more expensive than renewable energy.

Simon Evans summarised a study on world-wide CCS for the Carbon Brief. In 2014 he wrote that there were 22 active global CCS projects, of which only three were power stations. He went on to write that:

"So these 22 CCS projects – once they are up to speed – will be shaving 0.1 per cent off global emissions each year."

Gorgon project CCS

A recent example of the failure of CCS is in the Gorgon project in offshore gas fields of NW Western Australia. Nick O’Malley, National Environment and Climate Editor for The Sydney Morning Herald and The Age, wrote an article on 2021/07/20 about the failure of the Gorgon project to meet its key targets. The estimate in O'Malley's article was that a little over half of the aimed at carbon dioxide had been stored underground; another estimate of around the same time was that only about a third of the target was achieved.

Heat and humidity

While cold kills more people than does heat, or at least that has been the case up to the present, heat, especially when combined with high humidity, is a big killer.


Air pollution from burning fossil fuels is a far bigger killer

As mentioned elsewhere on this page, the air pollution from the burning of fossil fuels kills millions of people each year.
Heat, especially combined with high humidity, has been linked to over 600,000 excess deaths world-wide annually. As temperatures rise with climate change, heat related mortality is expected to increase.

As the climate warms the ability of the air to hold water vapour increases, higher levels of water vapour in the are is what are also called higher humidity.

Humidity is especially important to humans in tropical areas because of the already high temperatures and the fact that we rely on sweating to limit our body temperatures. But if the air already nearly saturated in water vapour then the sweat will not evaporate. Then the body temperature rises and in severe cases death can result.

Not just humans but most mammals loose heat through the evaporation of water, many animals sweat, some animals pant.

In wealthy nations many people have air conditioning, but most people in third world nations in the tropics don't. And even in wealthy nations, in a heat wave the power can fail with the loss of air conditioning.

An articles published by The Guardian, Global heating pushes tropical regions towards limits of human livability, provides more information.

Effects of climate change near me

Dead trees, egrets and spoonbills
A very few of the dead trees in the Len Howard Conservation Park.
In early 2022 my wife, Denece, and I moved from South Australia to Western Australia. Our new home state is suffering hugely from climate change, not least in the decreased rainfall that has led to a decrease of 80% in the amount of run-off into the reservoirs that used to be the mainstay of the state's water supply. See more on another page on this site.

Many thousands of paperbark trees have been killed in the Peel/Harvey estuary system of Western Australia by increased salinity that seems itself to be due to decreased rainfall connected with climate change. (Photo on the right)

And as discussed on another page, the only remnant population of red stringybark trees in South Australia are progressively being killed by increasingly hot and dry summers.

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When so much is known by so many about the seriousness of climate change why is so little being done?

From my observations of the people around me I'd say that together with the greed of those who profit from the status-quo (the fossil fuel moguls and industries and their hangers-on, for example, the Abbott and Morrison governments) the main reason is the apathy of the masses.

Just one example, while there is a good bus service along a main road near me, my observation is that only about 1% of the people on that road choose to use it, using their private cars instead, because that is more convenient, at great cost to greenhouse emissions.

My impression is that people will act on an immediate local threat, but are much less motivated to act on a global threat that will not reach its peak for decades or even centuries.

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A second Venus?
And the Paleocene-Eocene Thermal Maximum

There is a possibility that a runaway greenhouse effect will turn the Earth into a second Venus; a hellish place where the temperatures are too hot for any liquid water and for any life to survive.

A limited runaway greenhouse effect happened at a time geologists call the Paleocene-Eocene Thermal Maximum 55 million years ago. Wikipedia describes the event in detail, but it seems to have been a chain of events starting with volcanism triggering a temperature spike which then triggered release of massive amounts of methane from ices called methane clathrates in the deep seabeds and from melting arctic permafrost. It is estimated that the average temperatures around the world rose by between 5 and 8°C for a period of 20,000 to 50,000 years.

The present global warming of 1.5°C could trigger a similar limited runaway greenhouse effect, which would be disastrous for human civilisation, but since the last one, 55 million years ago didn't cause the Earth to become a second Venus it seems unlikely that a similar one in the near future would either.

A full runaway greenhouse effect is described in Wikipedia, so there is no need for me to go into any detail here. Put simply, water vapour is a greenhouse gas, as temperatures on Earth rise more water from the oceans evaporates increasing the amount of water vapour in the atmosphere and the greenhouse effect, this could theoretically feed on itself until all the water on Earth entered the atmosphere, as has happened on Venus.

The Sun, like all main-sequence stars, is getting gradually hotter over its 10 billion year life (it is about halfway through its life at present). So as the Sun ages any limited runaway greenhouse effect becomes more likely to initiate a full runaway greenhouse effect. However, if it didn't happen 55 million years ago it is unlikely to happen now. 55 million years is only about one percent of the the age of the Sun.

But do we want to take even that small risk of causing the end of life on Earth?

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A metaphor

Why should we all play our part in minimising the emissions that are causing climate change? Many people seem to have trouble with this. I have tried for a long time to think of a simple metaphor that might make it clear; today I thought of a good one.

Let's imagine that there is an island that is home to 100 families and its only fresh water supply is a spring that yields 100 kilolitres per day (one kilometre, kl, is one thousand litres, about 220 gallons).

If each family limited themselves to one kl they could all live happily together, but some families use much more than that so other families have to get by with much less. (Just as some nations produce much more than their share of greenhouse emissions and some nations produce less).

Let's say that the Joyce family is one of those that uses more than its share of the water. Mr Joyce justifies this by saying that if they halved the amount of water they used their garden would suffer and it would make only a tiny difference to the overall water supply situation.

The Abbott family also use much more than their share. Mr Abbott says that he doesn't believe there is any water supply problem at all - it's all made up by greenies.

The Morrisons, a 'good church-going' family, are part of a group on the island who are running a coal mine and exporting the coal. They need a lot of water for their mining and exporting operation. Mr Morrison says that the whole island profits from the coal mine and whatever they do they must keep it operating and even make it bigger.

A great many of the other families on the island are having to make-do with less and less water because of people like the Joyces, the Abbotts and the Morrisons. Surely the injustice in this is obvious.

In real life Barnaby Joyce is an ex-leader of the Australian National Party, Tony Abbott was an Australian Liberal Party Prime Minister, as was Scott Morrison.

Related pages/References

External links

The World Meteorological Organisation report, released 2024/03/19 showed that 2023 broke many climate records: greenhouse gas levels, surface temperatures, ocean heat and acidification, sea level rise, Antarctic sea ice cover and glacier retreat.

Quoting the report's key messages:

  • State of Global Climate report confirms 2023 as hottest year on record by clear margin
  • Records broken for ocean heat, sea level rise, Antarctic sea ice loss and glacier retreat
  • Extreme weather undermines socio-economic development
  • Renewable energy transition provides hope
  • Cost of climate inaction is higher than cost of climate action
The following sites provide informed comment on climate change science.

A brilliant graphical way of showing the warming of the world's climate from 1850 to 2016; apparently by Ed Hawkins.

The Conversation "Eighteen countries showing the way to carbon zero", 2019/02/26, by Pep Canadell, CSIRO; Corinne Le Quéré, University of East Anglia; and Glen Peters, Jan Ivar Korsbakken and Robbie Andrew, all from Center for International Climate and Environment Research - Oslo. Quoting from the article:

"Eighteen countries from developed economies have had declining carbon dioxide emissions from fossil fuels for at least a decade. While every nation is unique, they share some common themes that can show Australia, and the world, a viable path to reducing emissions."

University College London and The Lancet joint publication: a report calling climate change the biggest global-health threat of the 21st century; May 2009.

CSIRO updated climate change information for Australia, January 2015.

BAMS report 2012; The State of the Climate in 2012 – a suppliment to the August 2013 issue of the Bulletin of the American Meteorological Society.

The Global Warming Debate: A Layman's Guide to the Science and Controversy.

Real Climate: "Climate science from climate scientists"

Skeptical Science: Examining the science of global warming skepticism.

Motivated Rejection of Science: NASA faked the moon landing – Therefore (Climate) Science is a Hoax. Lewandowsky, Oberauer and Gignac.

Climate Debate Daily: A new way to understand disputes about global warming.

Global Warming Clearinghouse: A single source for contemporary key reports, articles, papers, and Blogs referencing the latest information available on Global Warming.

Climate Science Watch: Climate Science Watch is a non-profit public interest education and advocacy project dedicated to holding public officials accountable for the integrity and effectiveness with which they use climate science and related research in government policymaking, toward the goal of enabling society to respond effectively to the challenges posed by global warming and climate change.

NASA, Jet Propulsion Laboratory, Global Climate Change, Global Climate Change Key Indicators and Warming World.

CDIAC, Carbon Dioxide Information Analysis Center; "the primary climate-change data and information analysis center of the US.".

An interesing source on coral reefs and problems they have with climate change is the Global Coral Reef Alliance.

Plimer vs Monbiot. Ian Plimer's book, Heaven and Earth: Global Warming – The Missing Science, as the title suggests, rubbishes climate change science. This link points to a sequence of emails in which George Monbiot and Ian Plimer discuss Plimer's claims and Monbiot's criticisms of those claims.

ReNewEconomy article: rising ocean temperatures threaten the ocean food chain.

[Climate] Scientists Call Northwest [USA and Canada] Heatwave the 'Most Extreme in World Weather Records'. Written 2021/07/02 by Jake Johnson for Common Dreams.

Related pages: Climate science denial

The 5 telltale techniques of climate change denial by John Cook

Related pages on this site:

Greenhous/Climate change; from an Australian perspective

Ignorance, the problem and its prevalence

Climate change and the Covid pandemic; why the huge difference in responses?

Climate change in the Clare Valley

Tree deaths in the Peel lagoons of Western Australia seem likely due to climate change

Why accept climate science?

Australia's energy future; where I see my country's energy supply industry going in the future

Killer coal; not only is the burning of coal one of the main causes of climate change, its air pollution kills millions of people each year

End of coal; the coal industry is facing its end years

Potential disasters compared; which are most likely, how serious are they likely to be, and will society and the environment recover from them?

South Australia's great success in changing to renewable energy; my state is leading the nation, even the world

Two climate science deniers exposed: Alan Jones, Joanne Nova

Can we replace a lying, fossil-fuel obsessed, federal politician with an honest, climate-progressive, community independent?


On this page...
Air pollution caused by burning fossil fuels
Alternatives and the consequences?
Balanced media coverage
Biggest global-health threat of 21st century
Carbon capture and storage (CCS)
  Gorgon project CCS
Causes of anthropogenic climate change
Climate change
Climate change denial
  George Marshal on psychology of climate change denial
Climate change is even worse than we thought
CO2 in atmosphere and blood
Comparing the arguments
Consensus opinions of climate and earth scientists
Cost of climate change
Effects of climate change near me
Ethics of climate change
Historical recognition of possibility of anthropogenic climate change
Have these things happened before?
Heat and humidity
Hottest years on record
Is climate change happening?
Killer hail
Loss of mangroves
Marine life is fleeing the equator
Marshal on climate change denial
'Natural' disasters becoming more common
North Atlantic cooling
A metaphor
Monckton, 'Lord' Christopher
Ocean currents are becoming more energetic
Opinions of climate and earth scientists; a consensus
Paleocene-Eocene Thermal Maximum
Positive feedback
Precautionary principle
Psychology of climate change
Related pages
Related pages: Climate science denial
Science proves nothing
Sea level rise
Symptoms of climate change
Syrian war and climate change
A second Venus?
What is the science telling us?
Why accept that humanity is causing climate change?
Who are the experts?
Who is funding climate change denial?
Will spending on fighting climate change harm economies?