Protecting the Planet
(a WEA course)
Week 6: Global Warming (i) the science
Updated: November 2019.
1. Summary/overview: #overview
Global warming – man-made (anthropogenic) climate change - the most serious environmental danger we face.
Greenhouse effect, role of CO2, CFCs, methane...
‘Climate’ is not the same as ‘weather’. Effects are uneven.
2. Brief History of International Agreements on Climate Change #history
3. More detail on Global Warming – evidence and scale: #evidence
(i) Is it a scam? #scam
- 97% of climate scientists agree the world is warming as a result of our activities, mainly through carbon dioxide production.
- the Intergovernmental Panel on climate Change (IPPC) agrees, having scrutinised thousands of peer-reviewed studies.
- the Academies of Science of 34 different countries all signed the IPCC statement.
- the recent Paris agreement on climate change was signed by 194 countries.
(ii) Correlation of changes in CO2 with temperature change. #correlation
Evidence (Al Gore 2006): ice cores can be used to measure CO2 (bubbles) and temperature (isotopes of oxygen).
Ice ages and interglacial periods: during the ice ages the concentration of CO2 was below 200ppm, and large parts of the earth were covered with a sheet of ice a mile thick!
The ‘warm periods’ show levels of up to 260ppm. ‘At no point before the industrial era did the CO2 concentration go above 300 parts per million.’
Temperatures show dramatic and steady increase of around 0.5 degrees since the mid-20th century. Global temperatures have risen by almost 1 degree since 1880 (NASA).
Levels of CO2 now: 403.3ppm (parts per million) – highest for 3 million years. (WMO)
Recent high global temperatures. Increase in CO2 still going on (and effects will last, and we cannot remove it).
4. What does NOT cause global warming (sceptics claim these do): #other things
(i) Sunspots, (ii) the earth’s orbit or tilt, (iii) CO2 is heavy, how can it cause global warming? (iv) volcanoes... Other sceptics’ arguments (and response): (v) We cannot trust scientists: UEA emails, (vi) An Inconvenient Truth film taken to court (but no evidence of misrepresenting facts) (vii) Arctic ice is getting thicker, (but it’s covering less ground) (viii) There have been periods (mediaeval) when warming has not occurred (but short!) (ix) It’s a Chinese plot to undermine the USA, or a socialist plot (but US economy would benefit from change to low-carbon/renewables)
5. Who are the climate sceptics? #who?
5.1 NB: no refereed scientific papers deny global warming, while most (53%) newspaper articles give the ‘sceptical’ point of view equal space to the mainstream view.
5.2 ‘Doubt is our product’ – (tobacco company 1960.
5.3 Lobbying: American Enterprise Institute – contributions to Exxon Mobil.
5.4 key figures: Phillip Stott, Piers Corbyn, Nigel Calder, Nigel Lawson: not scientists, but mostly pro-market and on the right politically (see also Donald Trump!).
5.5 Representation in the press: three sceptics - Christopher Booker (Sunday Telegraph), Peter Hitchens (The Mail on Sunday), Matt Ridley (Times, former chair Northern Rock) vsone for consensus: George Monbiot (Guardian).
Many observers believe that the most serious threat facing the earth today is climate change as a result of global warming. The aspect of air pollution that is involved here is “the greenhouse effect”. When sunlight warms the earth, some of that heat is lost through radiation (bouncing off the earth) back into space. But there are some gases in the atmosphere that retain or reflect the heat back to earth – like the glass in a greenhouse. The effect, as noted below, was first discovered in the late 19th century.
Here we have another example of the precise balancing phenomenon at work in the ecosphere, since we are kept at just the right temperature for life to exist! (See the Gaia hypothesis). The most notable of these ‘greenhouse gases’ is carbon dioxide. In itself this is a harmless gas: we breathe it out all the time, when the oxygen we breathe in has been used in the lungs. (We could not live in an atmosphere of pure carbon dioxide, however). The balance of oxygen, nitrogen, carbon dioxide and other gases is just right for life.
However, human industrial activity - especially the burning of fossil fuels - including cars, has resulted in an increase in the amount of carbon dioxide, which has been carried up into the atmosphere and now keeps in some of the sun’s heat. Other contributing gases are CFCs (see notes on the ozone layer...) and methane: the latter is naturally produced by rotting vegetation, in ponds etc, but the amount of methane produced by human activity has actually increased with the industrialisation of farming, since cows’ flatulence contains the gas! A large proportion of greenhouse gases some from this source.
With regard to carbon dioxide emissions in the UK, levels are likely to be higher than government statistics suggest, and everyone agrees they are going to keep on rising so long as we continue to burn fossil fuel (especially coal and oil, but also gas).
There are a few people who say there is a correlation but not cause and effect – but given some of the changes to weather etc, and the measured warming of the globe, something is causing the temperature to rise, and the vast majority of climate scientists are convinced it is due to the greenhouse effect. (See the section on ‘sceptics’ below).
How does global warming occur? The role of CO2:
Sunlight enters the atmosphere as ultraviolet and visible light; some of this solar energy is then radiated back toward space as infrared energy, or heat. The atmosphere is 78 percent nitrogen and 21 percent oxygen, which are both gases made up of molecules containing two atoms. These tightly bound pairs don't absorb much heat.
But the greenhouse gases, including carbon dioxide, water vapor and methane, each have at least three atoms in their molecules. These loosely bound structures are efficient absorbers of the long-wave radiation (also known as heat) bouncing back from the planet's surface. When the molecules in carbon dioxide and other greenhouse gases re-emit this long-wave radiation back toward Earth's surface, the result is warming.
How do scientists measure CO2?
Scientists monitor carbon dioxide in the atmosphere by pumping air into an artificial chamber and shining an infrared light through the sample. Carbon dioxide absorbs infrared light very efficiently, ... so the amount of infrared absorbed can be used to calculate the amount of CO2
The research, published in Nature Geoscience, produces the clearest picture yet of the Earth’s average temperature over the most recent two millennia and reinforces concerns about the future impacts of global warming.
The study includes an update of the original ‘hockey stick’ curve, published by Mann, Bradley & Hughes twenty years ago. It was the first to note that late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1000 years. Since then, scientists from the palaeoclimate community have been working to construct an improved and expanded data set, and enhance the statistical methods underlying their reconstructions of global climate. In past millennia, we didn’t have the luxury of modern technology such as ocean buoys and satellites to gauge temperature, but nature recorded the answers for us. We just have to learn how to read those clues.
Corals, ice cores, tree rings, lake sediments and ocean sediment cores are examples of proxy data sources that provide scientists with a wealth of information about past conditions. This proxy data can be brought together to tell us a lot about the global climate system in the past.
Teams of scientists around the world have spent many thousands of hours of field and laboratory work collecting samples and analysing data. They publish and make freely available their precious data so that other teams of scientists can undertake further analysis. Previously, our team and other experts around the world, meticulously analysed, vetted and collated temperature-sensitive proxy data from around the world. We then made the full dataset publicly available.
With this unique dataset in hand, our team set about reconstructing past global temperatures.
Scientists are notoriously sceptical of their own analysis, but we are more confident about our findings when different methods applied to the same data yield the same result. In this latest paper, we applied seven different methods to a common underlying dataset. We found a remarkable resemblance in the multi-decadal fluctuations in temperature between the seven methods. We also found that climate models performed very well in comparison to our reconstructions, capturing the amplitude of natural variability in the climate system. This gave us the confidence to delve further, to try to understand what drove global temperature fluctuations before the industrial revolution took hold. To do this we used climate models and reconstructions of external climate forcing – a term which refers to influences from outside of the climate system such as volcanic eruptions and solar variability.
We determined that prior to the industrial revolution, global temperature fluctuations from decade to decade were mainly controlled by aerosol forcing from major volcanic eruptions - not by variations in the Sun’s output. So, in the centuries before human activity began to affect the climate – volcanoes controlled global temperature. There are, of course, natural changes in Earth’s temperature from decade to decade and century to century. With our new reconstructions, we were able to quantify the rate of warming and cooling periods across the past 2000 years. We found that at no time in that period has the rate of Earth’s warming been so high.
In statistical terms, all instrumental 51-year temperature trends starting after the 1950s exceed the 99th percentile of reconstructed pre-industrial 51-year trends. For increasing timescales, particularly those longer than 50 years, the probability that the largest warming trend occurred after 1850 swiftly approaches 100 per cent.
What does this mean in a nutshell?
It is yet further evidence of human-induced warming of the planet and illustrates that Earth is getting warmer, faster. Our understanding of Earth’s past temperature variations contributes to our understanding how life evolved, where our species came from, how our planet works and how modern climate change will unfold due to human activity. We know that over millions of years, the movement of tectonic plates and slow interactions between the solid earth, the atmosphere and the ocean affect global temperature. Over tens to hundreds of thousands of years, our planet’s mean temperature is gradually influenced by small variations in the geometry of the Earth and the Sun, like wobbles and variations in the Earth’s rotation and tilt.
At the Last Glacial Maximum about 26,000 years ago, huge ice sheets covered large parts of the Northern Hemisphere landmass.
The Earth then transitioned into a 12,000-year warm period called the Holocene.
This was a time of relative stability in global temperature, apart from the temporary cooling effect of the odd volcano.
With the development of human agriculture, our prosperity and population grew. Following the industrial revolution, rapid warming commenced due to human activity. Now, with a clear and concerning picture of temperature variations of the past few millennia we have a greater understanding of the nature of Earth’s recent warming. Is this what we really want for the future of our planet?
Researchers in this study include Neukom, R., Barboza, L.A., Erb, M.P., Shi, F., Emile-Geay, J., Evans, M.N., Franke, J., Kaufman, D.S., Lücke, L., Rehfeld, K., Schurer, A., Zhu, F., Brönnimann, S., Hakim, G.J., Henley, B.J., Ljungqvist, F.C. & Von Gunten, L.
We owe the teams of proxy experts much gratitude. It is their generous contribution to science and human knowledge that has supported this and other compilation and synthesis studies.
A version of this article also appeared in The Conversation.
Summary of the main effects of global warming:
The average surface-air temperature globally has risen by 1.4 degrees Fahrenheit (0.8 degrees Celsius) since the beginning of the industrial age. That's according to the fifth report of the Intergovernmental Panel on Climate Change (IPCC), released in 2014.
Sea-level rise has gone up globally by about 7.4 inches (0.19 meters) on average since 1901. According to the IPCC, the rate of sea-level rise since the middle of the 1800s has been higher than the rate during the previous two millennia.
2. Brief History of Climate Change (from Earthmatters, published by Friends of the Earth, Summer 2009, extra notes from Wikipedia and from Jonathan Watts, Guardian 10th Oct 2019: https://www.theguardian.com/environment/ng-interactive/2019/oct/09/half-century-dither-denial-climate-crisis-timeline).
1750 – 1800 start of industrial revolution – rises in average global temperatures are measured as from pre-industrial level.
1896 Swedish Chemist Svente Arrenhuis describes how greenhouse gases work and predicts a doubling of carbon dioxide in the atmosphere could increase global temperatures by 5 degrees.
1957 David Keeling measures changes in CO2 (Hawaii), correlates with fossil fuel use. Climate scientists now use the Keeling curve to describe the increase in CO2.
1959 Edward Teller tells the American Petroleum Industry a 10% increase in CO2 would melt the icecap and submerge New York. ‘I think that this chemical contamination is more serious than most people tend to believe.’
1965 Lyndon Johnson’s President’s Science Advisory Committee: ‘pollutants have altered on a global scale the carbon dioxide content of the air’ with effects that ‘could be deleterious’. The head of APIU: ‘Time is running out.’
1970s Shell and BP begin funding scientific research in Britain to examine the climate impacts from greenhouse gases. A recent lawsuit claims scientists told Exxon management in 1977 that scientific opinion ‘overwhelmingly favoured’ the view that fossil fuels were responsible for CO2 increases.
1979 first World Climate Conference highlights CO2 levels.
1980, 1981 scientists from API and others set up task force, and are told of likely ‘major economic consequences’ of a 2.5 degree rise. Internal Exxon memo warns of ‘later effects [that would be] catastrophic’.
1988 James Hansen of NASA testifies to US Senate that the greenhouse effect is changing our climate now.
1989 Global Climate Coalition established by US industry groups challenging the science and arguing for delays to action. Exxon, Shell and BP join 1993-4.
1990 IPCC: Intergovernmental Panel on Climate Change (established by United Nations Environment Programme, and World Meteorological Organisation) 1st Report says human activity likely to be contributing to climate change. Details of working methods etc. of IPCC at: http://www.ipcc.ch/index.htm
1991 Shell produces film acknowledging ‘possibility of change faster than at any time since the ice age... too fast for life to adapt without severe dislocation.’
1992 Rio Earth Summit or UN Conference on Environment and Development. 172 governments participate (2,400 representatives of NGOs, and 17,000 attended a parallel NGO Global Forum which had ‘consultative status’. Issues addressed included: patterns of production (toxic components such as lead in petrol, poisonous waste, radioactive chemicals), transport, air pollution, water, protection of land of indigenous peoples. à Framework Convention on Climate Change (UNFCC). US had reservations about the Convention. Also: Convention on Biological Diversity (US did not sign), and other statements. Criticised for not recognizing need to fight poverty.
1990s: Exxon funds Dr Fred Seitz and Dr Fred Singer who dispute the mainstream consensus on climate change. Both had previously challenged the hazards of smoking.
1995 2nd IPCC Report.
1997 Mobil places ad in New York Times: ‘the science of climate change is too uncertain to mandate a plan of action.’ (Mobil and Exxon later merge).
1997 Kyoto Protocol (building on the Framework Convention) signed by 192 parties (Canada withdrew in 2012 and US has not ratified it), to reduce greenhouse gas emissions ‘to a level that would prevent dangerous anthropogenic interference with the climate system.’ To come into force in 2005, and expire 2012.
1998 US refuses to ratify Kyoto protocol.
1999 Exxon CEO: ‘projections are based on completely unproven climate models (contradicting Exxon’s own scientists).
2000 Exxon ad: ‘Unsettled Science’ claims ‘scientists remain unable to confirm... humans are causing climate change.’
2001 3rd IPCC Report.
2001 George W Bush opposes Kyoto ‘because it exempts 80% of the world from compliance and because it would cause serious harm to the US economy’.
2002 Larsen B ice shelf breaks up – a piece of ice a quarter the size of Northern Ireland falls into the Antarctic Sea.
2003 estimated 35,000 Europeans die in extreme summer temperatures.
2004 sudden cold temperatures cause cracks in Empire State Building.
2005 Hurricane Katrina hits New Orleans.
2007 IPCC Fourth Report says there is a 90% chance that human activity is warming the planet, and that global average temperatures will rise by another 1.5 to 5.8C this century, depending on emissions.”
2007 IPCC and Al Gore share Nobel Peace prize. Gore’s film/powerpoint presentation An Inconvenient Truth wins an Oscar. ‘Washington Declaration’ initiates a ‘cap-and-trade’ system to apply to industrialised and developing countries.
2008 Ed Miliband climate change minister, UK passes Climate Change Act (world first).
2009 Barack Obama becomes president and puts billions into renewables.
2009 ‘Climategate’ – e-mails hacked from Climatic Research Unit at University of East Anglia – scientists accused of distorting evidence and suppressing opposing data. Attack is led by US Senator Jim Inhofe, whose main donors are in the oil and gas industry at the UN climate conference at Copenhagen, which ends in disarray.
2010 Reports by Lord Oxburgh, Sir Muir Russell and Commons Science and Technology Committee find no malpractice, no withholding of evidence and no suppressing of dissenting views. Public trust in climate scientists drops from 60% to 40%.
2009, 2010: Conferences in Copenhagen Cancun
2012 Doha extension of (1997) Kyoto Protocol: 37 countries adopt binding targets (of which 7 have ratified), by July 2016 the number of countries adopting it rose to 66, but 144 are required for it to enter into legal force. EU and others agree to extend treaty to 2020.
2013 Richard Heede of Climate Accountability Institute shows 90 companies are responsible for two thirds of the CO2 entering the atmosphere since the 1750s.
2015 Paris Conference (UN Climate Change Conference – COP21: 21st annual session of the Conference Of the Parties to the 1992 Framework Convention). 196 parties attended. Agreement will enter into force when joined by at least 55 countries representing at least 55% of global greenhouse emissions.
2016 Earth Day – 22nd April: 174 countries sign in New York. Goal: to limit global warming to less than 2 degrees Celsius compared to pre-industrial levels. Parties will also ‘pursue efforts to’ limit the increase to 1.5 degrees. This will require zero emissions between 2030 and 2050.
2017 Exxon, Chevron and BP each donate at least $500,000 for Donald Trump’s inauguration. Later he announces he will pull out of the Paris agreement.
2017 Nov 6th, COP23 in Bonn: 10,000 government delegates, 8,000 others. Fiji is chair.
2018 US, Saudi Arabia Kuwait and Russia dilute a landmark UN report on dangers of global warming beyond 1.5C.
2019 secretary general of OPEC: climate campaigners are the biggest threat to industry and are misleading the public.
(Notes initially written in response to a paper by a student on one of my WEA courses, who said climate change is a ‘disaster myth’):
It seems to me that a small group of ‘sceptics’ manage to have an influence that outweighs their number and their importance. It may be a bit odd to arrange these notes in the form of a ‘reply to sceptics’, but I was prompted to do so, a few years ago, by a detailed paper prepared by a student – until then perhaps I had been guilty of assuming that everyone knew how global warming worked!
I have also recently (2016) had cause to write to a local paper, because they have printed at least two letters from a local councillor who is a climate sceptic! The councillor’s argument was (in part) that changes in CO2 occur after changes in temperature, not before.
I wrote two replies, and the second (which they published) points out that no sources were given for this claim, while:
- ‘97% of climate scientists agree the world is warming as a result of our activities, mainly through carbon dioxide production.
- the Intergovernmental Panel on climate Change (IPPC) agrees, having scrutinised thousands of peer-reviewed studies.
- the Academies of Science of 34 different countries all signed the IPCC statement.
- the recent Paris agreement on climate change was signed by 194 countries.’
I added that in the light of this ‘It is just nonsense to talk of a 'scam' perpetrated by mysterious 'interests' (which is what climate sceptics often say) - as it is no-one's interests to deny that global warming/climate change is happening. The World Health Organisation has said that 'climatic changes already are estimated to cause over 150,000 deaths annually.'
My letter ended: ‘In my view it is irresponsible of a local paper to keep printing these false claims when across the globe people are already suffering from the effects of climate change.’ However, this sentence was not printed!
I hope this explains my concerns over ‘climate scepticism’!
Update: the same councillor has repeated his claims more recently (2019) and myself and a few other people have been arguing against him.
I replied to various points made in the student’s paper as follows:
NASA has a graph on their website: http://climate.nasa.gov/keyIndicators/ which takes a mean temperature between 1951 and 1980 and plots the changes since 1880. It shows that around 1880 the temperature was 0.4 (degrees Celsius) below the mean, and now it is approaching 0.6 above. You can either say this is a 0.6 rise or I guess you could say it is 1 degree. I have seen other figures of 0.8 (Robin McKie – science editor of the Observer newspaper) or even more... and if, as many argue, the warming is a trend, then mean temperatures are likely to carry on increasing. There is a great danger if the upwards curve is, as Al Gore and others argue, exponential.
In his 2006 book, An Inconvenient Truth, Al Gore points out (p65) that scientists (he quotes Dr Lonnie Thompson, School of Earth Sciences, glaciologist, Distinguished University Professor at Ohio State University, and Senior Research Scientist at the Byrd Polar Research Center at Ohio) can measure both the past temperature of the earth’s atmosphere and the amount of CO2 in it, by examining ice cores. The CO2 is present in bubbles in the ice, and the ratio of different isotopes of oxygen (Oxygen 16 and Oxygen 18) records the temperature. He prints graphs (p64) which show the changes over the past 1,000 years. These show a dramatic and steady increase of around 0.5 degrees since the mid-20th century. Andrew Simms, G2 19th Jan 2017 says ‘temperatures have risen by almost 1 degree since 1880.’
There have been other fluctuations – such as the ‘medieval warm period’ – but this can be seen to have been a small, short-lived ‘blip’.
Perhaps the most striking chart, however, shows (p66-7) measurements in Antarctica going back 650,000 years. Here it is really clear that the changes in temperature and in CO2 concentration correlate very closely. You can see ice ages with periods of warming in between. During the ice ages the concentration of CO2 was below 200ppm, and this means large parts of the earth were covered with a sheet of ice a mile thick! The ‘warm periods’ show levels of up to 260ppm. ‘At no point before the industrial era did the CO2 concentration go above 300 parts per million.’
Current levels of CO2 are around 408 ppm (parts per million) – and this has increased in the last few years (2013 – 2017) (Wikipedia, quoting National Oceanic & Atmospheric Administration). Note that this is (only) 0.04% by volume... [Note also: CO2 is essential for life, as the carbohydrates in the plants we eat are our primary source of energy; carbohydrates are made by plants through photosynthesis, which uses sunlight to convert CO2 and water into carbohydrates]. There has been a 40% increase (from 280 to 400) since the start of the industrial revolution in the middle of the 18thcentury. The level of 280 ppm held for 10,000 years before the industrial revolution. The present concentration is the highest in at least the past 800,000 years, and likely the highest in the past 20 million years (Climate Change 2001: The Scientific Basis). It is currently rising at a rate of approximately 2ppm per year – and accelerating (Peter Tans, Trends in Carbon Dioxide, NOAA/ESRL).
These increases may appear small, but:
(a) only a few degrees (5 – 10) drop would produce an ice age, and Robin McKie, drawing on UN sources, says that an increase of 2 degrees would lead to 3 billion people suffering water shortages, and global food production being disrupted: http://www.guardian.co.uk/commentisfree/2010/dec/26/robin-mckie-carbon-emissions-up
(b) taking a global average, the 20 warmest years have occurred since the 1970s, and the 10 warmest years have occurred in the last 12 years (NASA) – the rate of change seems to be accelerating (see the point below on exponential growth). 2016 has been the hottest year to date, and each preceding year has shown warming.
However, an increase in global temperatures does not mean that everywhere gets warmer! There is a difference between weather and climate, and the weather effects of global warming are not easy to predict. However, Al Gore (2006) - see point 9 below - lists not just glaciers melting but also some places getting more rain, some having droughts, more hurricanes and other extreme weather events; the more frequent closing of the Thames flood barrier etc. The Association of British Insurers has pointed out that claims from storm and flood damage doubled between 1998 and 2003 (to over £6 bn) (sorry, I forget my source for this!).
Already Bangladesh suffers damaging floods, and these could become worse. In Britain the Thames Barrier has been raised more often recently (19 times in 2003, as against 3 times in 1983) – there is even talk of building another flood barrier. Just as worrying is the possibility that weather conditions will change so that there are more storms, hurricanes etc. Or, temperature changes (e.g. to the Gulf Streamwhich warms Britain’s coast line) would affect crops and even turn some areas to desert.
We have already had freak weather conditions in Britain – the floods in Cornwall, at Boscastle in 2004 for example – and scientists such as John Schellnhuber, of the Tyndall Centre, warn that things could get worse (Observer 7/11/2004). Apart from the damage, Schellnhuber and others argue that a point will come when insurers will not be able to pay for the damage: Insurers Munich Re believe that by 2060 the “cost of our changing weather will outstrip the total value of commodities and services produced by the global economy” The United Nations reports that the number of natural disasters has doubled over the past decade, and resultant economic losses have more than trebled. (Observer loc cit)]
A piece in New York Times (Sat Apr 15th 2012) asks whether the more variable weather we now see in the northern hemisphere is a result of climate change. In March parts of the US were very cold, after a freak heat wave – in France it was the other way round...
An IPCC report issued in late March (2012) suggested there is a link, and that climate change is leading to increased frequency of heat waves, and of heavy rainfall, and coastal flooding. The most likely explanation is that this is connected to the melting of Arctic ice, which has shrunk 40% since the early ‘80s – an area the size of Europe is now water, which does not reflect heat away from the surface as ice does. Dr Jennifer Francis of Rutgers University (quoted in the NYT article) says the question is ‘how can it not be’ (how can the loss of sea ice not be affecting atmospheric circulation). In particular, the heat is probably affecting the jet stream, producing ‘kinks’ which disrupt the normal temperatures.
Andrew Simms (loc cit) points out that in the Arctic in Nov 2016 the temperature was 20 degrees C above normal! Giant icebergs are breaking off in Antarctica.
However, some scientists dispute the link between extreme weather and climate change (loc cit): John R. Christy, University of Alabama, says it is simply down to the very dynamic nature of weather. Martin P. Hoerling, National Oceanic and Atmospheric Administration analyst, says what is happening in the Arctic is mostly staying in the Arctic, and some researchers are in too much of a hurry to establish a link between weather and human causes. But please note: these are arguments about the exact effects of climate change/global warming, not about the underlying trends. The same point needs to be made with reference to the criticisms of the IPCC report which claimed glaciers would melt quickly: this section was written by a separate group to the scientists who measured temperature change etc, and whose task was to speculate about the impact. No errors have been pointed out in the scientific summaries.
(c) the crucial point is that previous rises/falls (going back 600,000 years) have correlated very clearly with the amount of CO2 in the atmosphere, and the vast majority of scientists believe the major cause of the increased global temperature is increased CO2, not other factors such as:
There has been a low level of sunspot activity between 2005 and 2010 – the lowest levels recorded during the satellite era. This means that the earth has been absorbing less energy from this source – recent (2011/12) calculations by the Goddard laboratory for NASA (cited on the NASA website – see References below, and in Hansen’s book) show about 0.25 watts per square kilometer. But the earth’s ‘energy imbalance’ (the difference between energy absorbed by the earth and energy returned to space) is 0.45 watts per square kilometer, that is: there is more energy generated inside the system than the amount that exits (a positive imbalance). Temperatures have been going up – but solar activity cannot be a cause of this. Solar activity varies over 11 year cycles – usually pretty regularly, despite the latest dip (see the next point).
(ii) Another key factor is the orbit and tilt/wobble of the planet:
There are of course natural cycles which affect the climate (including variations in solar irradiation, La Nina etc) – and no proponents of man-made climate change would deny this! The point is that these are natural changes, and pretty much predictable (because their patterns are usually regular), which work over long cycles – whereas the pumping of CO2 into the atmosphere through burning fossil fuels is not natural, and can be shown to have affected the composition of the atmosphere dramatically in a short time:
The increase was first measured by David Keeling in 1957 (Hansen p 116) – and he also noticed a 24 hour cycle as trees and plants absorbed CO2 during the day and gave off CO2 during the night. He also found that there were variations near to human habitation – which is why he then made more measurements at a remote spot at Mauna Loa, Hawaii.
His measurements, which have never been refuted, (Robin McKie) show that CO2 increased from around 310 ppm to over 390 between 1957 and 2010. (*) There is no doubt that the levels will continue to rise unless major changes are made in the way energy is generated. Moreover, CO2 remains in the atmosphere for some time so that there is a time-lag: even if we start reducing our output now, the results will not be noticeable immediately.
Scientists believe it is important to reduce the level to 350 ppm to restore the energy equilibrium of the planet.
(*) This is a rapid change over a short period of time – and the rate of change seems to be accelerating. This is probably what is called exponential growth – like a compound interest savings account where the amount of increase each year goes up if the interest is left in. However, in nature exponential growth is very dangerous: nothing serious seems to be happening at first, but when the change gets more rapid we get to a ‘tipping point’ beyond which it is impossible to reverse the change. (The example I usually use to illustrate this is a pond in a garden: if weeds, say, are growing exponentially this means that the time in which it takes them to double the space they take up gets shorter and shorter. It is quite possible for weeks of growth to occur before the weeds cover half the pond, but they will then fill it entirely overnight! Your fish will suffocate before you have done anything about it.)
(iii) CO2 is a heavy gas and falls out of the atmosphere:
There is a CO2 or ‘carbon’ cycle – described by Hansen on pp 118 ff: plants, the oceans and the land act as ‘reservoirs’ for CO2 (plants/trees hold 600 billion metric tons [gigatons or GtC] primarily as wood in trees, soils contain 1,500 GtC, and the ocean holds 40,000 dissolved GtC – the atmosphere holds about 800 GtC as CO2). Again, we know there are natural cycles such as the glacial to interglacial periods due to the movement of the earth in space. Also, when the ocean becomes colder it holds more CO2, so the atmosphere then holds less and this leads to more cooling. But when snow and ice melt, due to the earth’s changing orbit or tilt, then more CO2 is released, leading to more warming. These are examples of positive feedback – and Hansen says they account for nearly half the interglacial global temperature change.
An estimated 30-40% of the CO2 released by humans into the atmosphere dissolves into oceans, rivers and lakes which contributes to ocean acidification: we will deal with the various consequences of global warming later.
The crucial point, once again, is how human activity is interfering with these natural cycles.
(iv) Other natural phenomena such as volcanoes affect the picture:
Yes Mount Pinatubo erupting in 1991 had an effect on global temperatures, by the aerosols it put into the atmosphere: it ‘reduced solar heating of Earth by almost 2%... this... however, was present only briefly – after two years most of the Pinatubo aerosols had fallen out of the atmosphere.’ (Hansen: Storms of my Grandchildren, Bloomsbury 2009, p 5). If there were a series of volcanoes continually erupting we would see a longer-term change.
Hansen in fact identifies no fewer than 9 ‘climate forcings’ – factors that affect the climate (p 6):
- other greenhouse gases,
- black carbon aerosols,
- reflective aerosols,
- aerosol cloud changes,
- land cover change,
- the sun
- and volcanoes.
Hansen gives precise quantifications for the different amount of effect each has... and concludes that CO2 is the most significant. This is neither a ‘myth’ nor what you call ‘denial’ (!) but scientific work based on real, detailed and thorough measurements.
(v) Global warming is being unfairly used by such scientists as those at East Anglia University, to explain famines, when these are man-made:
(i) I am not aware of any environmentalists who would say climate change is the only factor in food shortages. UNEP (UN Environmental Programme) did suggest that the Darfur problem originated in climate change, and it seems to me incontrovertible that failure of rainfall causes crops to fail. Of course, civil conflict is a crucial factor as well in these crises, and in some parts of the world civil war has aggravated food shortage, (see John Vidal, Guardian 22.07.11, on the contribution of climate change + war to famine in Somalia) but would you want to rule out climate change altogether?
(ii) Please remember that ‘climategate’ originated when the computer at EAU’s Climate Research Unit was hacked into (by whom?) in order to release emails, which then were publicised by Fox News and other anti-global warming media. Eight committees have since investigated the CRU emails, and no evidence has been found of fraud or scientific misconduct. The scientific findings are not in doubt. The researchers did ‘fail to display the proper degree of openness’ in responding to queries about their data. I suspect they were bombarded with requests from would-be deniers and simply lost patience. Every time I encounter a climate-change sceptic I get the same feeling!
(vi) The film ‘An Inconvenient Truth’ was so full of errors that is was banned from being shown in schools:
The film has not been banned, and the court that was asked to ban it did not disagree with its central theme:
BBC (online) News 11th Oct 2007: A campaign to stop the government sending DVDs to all secondary schools as part of a climate change package was started by a parent governor Stewart Dimmock (a member of the [right-of-centre] New Party). ‘The judge said he had no complaint about Gore’s central thesis that climate change was happening and was being driven my emissions from humans.’ He had reservations about 9 specific points which were not backed up by sufficient scientific agreement, including:
- the claim that polar bears have drowned because they have had to swim further (some have died in storms);
- the claim that sea levels would rise by 6 metres in the near future (it would take millennia said the judge);
- there was also ‘not sufficient evidence’ that global warming caused hurricane Katrina;
- ditto for the melting of snows on Mt Kilimanjaro, or evaporation of Lake Chad.
The judge said that the film should have guidance notes accompanying it to draw pupils’ attention to these points. ‘The government has sent the film to all secondary schools in England, and the administrations in Wales and Scotland have done the same.’ A 60 page guidance document now goes with it.
The book has many, many examples of the effects of global warming, and it seems significant to me that the court ruled that only the specific ones cited were doubtful.
(vii) Polar ice is not melting:
You can check out details of all this on the NASA website, which has a ‘Global Ice Viewer’ that illustrates dynamically the changes that have been taking place - e.g. the annual minimum amount of Arctic ice (it shrinks in the summer and grows in the winter) has been decreasing by 11.2% per decade over the past 30 years, and in 2007 reached the lowest recorded level.
Greenland’s glaciers are losing 100 – 250 billion tons of ice each year and 400 billion tons has been lost from all glaciers per year since 1994, W. Antarctica has been losing up to 150 billion tons of ice per year). It seems to me that even if (as you claim) the ice is thickening - which the NASA figures at http://climate.nasa.gov/evidence/ deny – still the area occupied by the ice has shrunk, and so less heat is reflected back into space and the warmer the planet gets (positive feedback).
Moreover, other changes have occurred in the oceans:
- sea levels have risen by 6.7 inches (17 centimeters) in the last century (approx 4 mm per year)– the rate of change in the last decade has been double that of the previous century.
- the oceans’ acidity has also increased by 30% since the beginning of the industrial revolution (NASA – full references on the webpage; a change of 0.1 pH = 30% acidification)
- plankton, which control the carbon cycle, nitrogen cycle and part of the oxygen cycle (every second breath we take is of oxygen from plankton), are dying off as the oceans warm.
(viii) There have been other periods of temperature change.
Yes but these have been short-lived and due to natural events – the current changes are mad-made, and they show a steady rise of temperature which cannot be reversed.
(ix) It’s a Chinese (or communist) plot!
This reveals the most common denominator among climate sceptics: opposition to the state and to governmental regulation. See below on lobbying... It is worth stating that the US economy would benefit from a change to renewables (see Protecting the Planet 7: effects of climate change) – provided government subsidies are not used for other kinds of energy production. Lord Stern pointed out that we would save money by trying to prevent global warming, as the costs if it increases are huge....
5. 1 The biased media:
Al Gore in his book cites a study done by Dr Naomi Oreskes of University of California, which was published in Science magazine. She took a random sample (about 10%) of all the peer-reviewed science journal articles on global warming from the previous 10 years. There were 928 articles in the sample, none of which raised any doubts about the cause of global warming (though only three-quarters addressed the 'central elements of the consensus' and the rest were about specific issues not to do with CO2). On the other hand, another study was done of all the articles in the previous 14 years from what were considered as the four most influential papers in the US (New York Times, Washington Post, LA Times and Wall Street Journal). Again a random sample was taken, amounting to almost 18% of the articles, and this time 53% gave equal weight to the 'consensus view' and to the opposition (sceptics/deniers) - thus giving the impression there was disagreement in the scientific community about the issue. (See more below).
He follows this up with points about how the tobacco industry adopted exactly the same tactics when the link with cancer was identified: a memo was uncovered from the Brown and Williamson Tobacco Company, written in 1960: "Doubt is our product, since it is the best means of competing with the 'body of fact' that exists in the mind of the general public. It is also the best means of establishing controversy."
Update: ‘Desmog’ has very useful details of climate crisis deniers, and how they operate, for example: https://www.desmog.co.uk/2019/06/20/chief-government-climate-advisor-cleared-wrongdoing-house-lords
The lobby group American Enterprise Institute, (AEI), an ExxonMobil-funded think-tank, has offered scientists and economists $10,000 each for articles questioning the report of the UN’s Intergovernmental Panel on Climate Change (IPCC)…. The AEI has received more than $1.6m from ExxonMobil, and more than 20 of its staff have worked as consultants to the Bush administration.
Robin McKie, Observer, 04.03.07(?), points out that those who contest the scientific consensus, e.g. Phillip Stott, Piers Corbyn, Nigel Calder, Nigel Lawson, have often got a political agenda. To deal with global warming, says McKie, quoting philosopher John Gray, will require government action and intervention in our lives – and probably bureaucracy – all of which is anathema to the sceptics, several of whom have pronounced pro-market views. (We are told, for example, that Europe will ban the inefficient fluorescent light bulb: I wonder if the Daily Mail will start a campaign to save it?!)
The names that McKie gives are of people who regularly can be heard on Today and seen on Newsnight (so they cannot claim, as they do, that there is a conspiracy of silence over their views!).
5.5 The Press (again)
Date? Mail on Sunday criticised by UK press regulator, for claiming that global warming data had been exaggerated in order to get agreement at Paris. The paper said data from US National Oceanographic and Atmospheric Administration had been treated. The controversy arose over a ‘pause’ in global warming (used by deniers to claim warming had been exaggerated) – 1998 was exceptionally hot owing to a strong El Nino effect. But these years still showed an upward trend compared to the average, so talk of a ‘pause’ was misleading. Fiona Harvey.
Dec 2017. Peter Wilby (New Statesman 16 Dec 2016 – 5 Jan 2017) says: ‘By my calculations, ten global-warming sceptics – including the Sunday Telegraph’s Christopher Booker, The Mail on Sunday’s Peter Hitchens, and the Times’s Matt Ridley – have regular columns in the main sections of national newspapers.’ According to Geoffrey Lean, environmental correspondent (formerly of Telegraph, Independent on Sunday and Observer) ‘There used to be four of us [columnists in national newspapers accepting the consensus]. But three of us have been sacked in the past 18 months.’ Only George Monbiot remains...
Updates (oldest first)
June 2011. Another argument that comes up from time to time is that the solar minimum will cause a cooling. It is said there was a solar minimum during the ‘little ice age’ – however, recent scientific studies show that the most likely outcome would be very slight cooling that would make no difference to overall warming:
Sep/Oct 2013. Denying Climate Change:
Mehdi Hasan has a brilliant piece in new Statesman (27th Sep – 3 Oct 2013)
Deniers are ‘merchants of doubt’, whose ‘doubts’ cost lives, and they are conspiracy theorists. To doubt the findings of thousands of peer-reviewed articles, when of 928 articles produced between 1993 and 2003 not one rejected the consensus, and when 97% of climate scientists are in agreement, you have to believe the unbelievable (‘the greatest hoax ever perpetrated against the American people’, according to US Republican senator James Inhofe).
Hasan quotes an interview with Richard Lindzen, professor of meteorology at MIT, who when asked why the national academies of 34 different countries all signed the IPCC consensus position, suggested they are ‘dependent on the goodwill of the government. And if they’re told ‘sign on’ they’ll sign on.’
According to the WHO ‘climatic changes already are estimated to cause over 150,000 deaths annually.’
The Observer Editorial, 29th Sep 2013, points out: deniers claim the global temperature is no longer rising, when the rate of increase has only slowed down (and is expected to dramatically increase in future), others say Arctic ice is not shrinking when it reached its sixth lowest extent this year; one national newspaper claims the Arctic loss is balanced by the Antarctic gain, when the Arctic loss is 3m sq km of ice in the last 30 years, and the Antarctic has gained 0.3m (probably just year-to-year variability). More worrying is the presence in Cameron’s government of such people as: Peter Lilley (who voted against the climate change act of 2008), and Owen Paterson, a sceptic as environment secretary(!).
2016. Extra notes from DeSmogUK – the Brexit connection:
There is a deep-rooted connection between UK climate science deniers and those campaigning for Britain to leave the European Union, new mapping by DeSmogUK can reveal. Tying together this close-knit network reveals how organisations residing behind the doors of Westminter's 55 Tufton Street share many of the same members and donors. And the reach of this small group of Brexit climate deniers extends beyond this Westminster building to include prominent politicians such as former London Mayor Boris Johnson, Justice Secretary Michael Gove, and Energy Minister Andrea Leadsom as well as traditional British media outlets. Perhaps the epitome of this nexus between climate science deniers and Brexit campaigners came last week when former environment secretary Owen Paterson delivered a speech at this very same address. Advertised by Grassroots Out and hosted by Paterson’s UK2020 think tank, Paterson argued “Why the UK environment would be improved by leaving the EU.” His speech was quickly criticised for being out-of-touch by Green MP Caroline Lucas, who said: “I’m as likely to ask Donald Trump for advice on race relations as I am to trust Owen Paterson on protecting our environment.”
But it's hard to ignore the political movers and shakers working inside the walls of this four-storey, multi-million pound building located just steps from the Houses of Parliament. This small, mostly male, contingent is a significant driving force behind the 'leave' side of the 23 June EU referendum and the same group that wants less, not more, done to tackle catastrophic climate change. The overlap stems from a common neoliberal ideology that fears top-down state interventions and regulations which are perceived as threatening values of individual freedom, economic (market) freedom, or the sovereignty of national governments. Under this logic, we must reject both the European Union and most climate policy.
It begs the question: If Britain leaves the EU, what will then happen to the country's climate change policy?
Mapping the Bubble
Delving into the web, you’ll quickly get a sense of the deep-rooted connection between these various organisations. DeSmog UK first reported on this relationship in January when a slew of climate science deniers published comment pieces blaming European bureaucracy, not climate change, for the December flooding. Then, in February, the Independent revealed that these inter-related groups all share the 55 Tufton Street address. So now, with the Brexit vote less than two weeks away, DeSmog UK has for the first time mapped, in-depth, the climate-euro sceptic bubble for you to explore.
How to use the map: Zoom in and out to see the web of relationships between the residents of 55 Tufton Street and its neighbours. Hover over the lines to see the type of relationship between the two entities, and click on the person or organisation’s name to find out more (this will open up a new tab where you can find out more information about all of this entity’s various relationships and stance on climate change).
Looking at the map, you will see 55 Tufton Street at the centre. Above, you have the building’s owner, Richard Smith, and below you have two rows: organisations which currently reside (or did until recently) at this address, and key figures within each organisation. And then you have the many other relationships that are derived from this.
Please note that this is not an exhaustive list of all people affiliated with each 55 Tufton Street organisation. Nor is it likely to be an exhaustive list of all the relationships between the entities included in the map. If you spot something we’ve missed, let us know in the comments section below.
Who is Richard Smith? He keeps a low profile and is perhaps best known for when he flew David Cameron to his home in Shobdon, Herefordshire in 2007. The Midlands businessman owns HR Smith group, which works on advanced aerospace technologies. Not only is he associated with several of the organisations at 55 Tufton Street, but as the map shows, Smith has also donated money to the Vote Leave campaign, Labour Leave, and the Bruges Group (via his company Techtest).
Meet Vote Leave’s climate science deniers: The prominent Vote Leave campaign group draws several of its members from Paterson’s UK2020 think tank and Lawson’s Global Warming Policy Foundation (GWPF), including Matt Ridley who’s a member of both. UKIP MP Douglas Carswell is also a supporter of Vote Leave – Carswell is known for saying his biggest regret is voting in favour of the 2008 Climate Change Act.
The TaxPayers’ Alliance’s ties to everyone: In 2010 following the general election, the TaxPayers’ Alliance hosted a roundtable meeting to discuss the Conservative Party’s return to power. Among those in attendance included the GWPF, Global Vision, the Centre for Policy Studies, the Institute of Economic Affairs, as well as oil giant BP.
Matthew Elliott: While not at the centre of the map, Elliott is definitely at the centre of many of the 55 Tufton Street organisations, including the TaxPayers’ Alliance (and its donations wing, the Politics and Economics Research Trust), Vote Leave, Business for Britain, and The European Foundation. It’s also interesting to note that Elliott’s wife, Florence Heath, is a petroleum geologist who at one time worked for Shell and was a Charles G. Koch fellow at the Competitive Enterprise Institute (known for promoting climate science denial) in the summer of 2001.
Within the GCC, the Science and Technology Assessment Committee (STAC) took responsibility for assessing contemporary climate science and formulating strategic arguments to undermine it. The STAC was chaired by Mobil Oil’s Lenny Bernstein. Mobil, Exxon, and Texaco (now part of Chevron) all contributed five staffers to the committee.
An internal 1994 document outlining “issues and options” for the GCC to consider regarding “potential global climate change” shows the group’s outright climate science denial.
The document concludes that “the claim that serious impacts from climate change have occurred or will occur in the future has not been proven” and “consequently, there is no basis for the design of effective policy action that would eliminate the potential for climate change.”
July 2019 reports show consensus is probably over 99% that the earth is warming:
Aug 2019 civil servants in climate change dept are flying more often! Last year civil servants in the Dept for Business, Energy and Industrial Strategy (BEIS) took more than 4,500 flights, compared with 2,700 the year before. The dept claimed to be making progress in reducing its carbon emissions, however: total emissions fell from 30,000 tonnes the previous year to 22,700 last year. This was due to reduction in amount of gas used to heat the dept building at 10 Victoria Street, after energy efficiency upgrades.