Climate change and heath: primary, secondary and tertiary effects

This is a preview of part of chapter 31 ("From Paris Towards 1.5 Degrees C) the additional chapter I am now writing for the forthcoming softcover issue of my edited book, Climate Change and Global Health, (CABI, 2016).

"The health chapter of the recent IPCC report concluded with a three tier classification of the possible health effects (see box). Though no source is quoted it may have been influenced by the “primary, secondary and tertiary” structure used in my edited book, Climate Change and Global Health, which in turn is derived from two earlier papers (Butler, Corvalán et al. 2005, Butler and Harley 2010) (see box).

Soon before the release of this book, I attended a meeting on climate change and health run by the World Health Organization. At it, I learned that the IPCC health chapter (to which I was a minor contributor) had concluded with a three tier classification of the likely health effects of climate change (see box 31.1). It was encouraging to see that my fellow IPCC authors appreciated the existence of a third broad category, which is the framework of this book, based on ideas and papers I have promoted for two decades (Butler and Harley, 2010, Butler et al., 2005, Butler, 2014). But I was also disconcerted. Contrary to the IPCC principle which recommends its material to be based on existing literature, the framework was unattributed. The IPCC conceptualisation placed mental “illness” in the third category, rather than seeing mental health as a crosscutting issue (see Figures 26.1 and 26.2). Frustratingly, this framework made no clear statement that the third (tertiary) category is likely to have a much higher burden of disease (BOD) than the others (see Figure 26.2). If enough people of influence, especially in the media and government can see the risk of the third category then we might collectively act to reduce and to defer it. For this to occur, the enormous BOD risk of tertiary effects needs to be explained and stressed.

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[1] When the publisher of this book approached me I agreed to edit on condition that it followed a three tiered classification, of which the third (tertiary) category is by the most important, following ideas I first started to consider over 25 years ago, as discussed in Butler and Woodward, 2015).

BOX 31.1

“Climate change affects health in three ways; 1) Directly, such as the mortality and morbidity (including “heat exhaustion”) due to extreme heat events, floods, and other extreme weather events in which climate change may play a role; 2) Indirect impacts from environmental and ecosystem changes, such as shifts in patterns of disease carrying mosquitoes and ticks, or increases in waterborne diseases due to warmer conditions and increased precipitation and runoff; and 3) indirect impacts mediated through societal systems, such as undernutrition and mental illness from altered agricultural production and food insecurity, stress and undernutrition and violent conflict caused by population displacement, economic losses due to widespread “heat exhaustion” impacts on the workforce, or other environmental stressors, and damage to health care systems by extreme weather events” (Smith, Woodward et al. 2014).

Both figures are from  Chapter 26 ( Butler C.D, Bowles D.C., McIver L., Page L. (2014) Mental health, cognition and the challenge of climate change. In: Butler C.D., editor. Climate Change and Global Health. CABI, Wallingford, UK: CABI; pp 251-258.)

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No classification is perfect, none should be considered inviolable .. but the main idea of the third category is to try to convey that climate change related health risks are lot more significant (and terrifying) than (say) heatstress or a heightened chance of malaria.

To me, most conceptualisations are a bit like impressionist paintings. The other element involved with tertiary is causal distance .. there are still a lot of people denying climate change can influence conflict or migration, for example. (Which leads into the x access label in Fig 26.2) ..

Oreskes and Conway (2013), writing from the future, reflect on the collapse of civilisation, reflect on the bias most scientists have towards "type II" errors (ie waiting too long to make a conclusion). If, by say 2150 Miami etc has disappeared and WWIII has passed then we might agree climate change contributed to the devastation that had transpired .. by which time it’s too late. 

The late Tony McMichael has called the tendency to not think hard enough about cause as "epidemiologising", or looking under the lamp post, because that's where the light is, even if the keys aren't likely to be.

When I give lectures on this (eg see slides given to the ANU medical students last month), I spend a lot of time on Fig 26.2. I tell people it’s the most important slide in the whole lecture, the whole book.. (No one so far has either challenged or explicitly agreed with me on that, so I’m not sure if people understand..)

Post-script (added November 20, 2021): In 2018, while working on "Climate Change, Health and Existential Risks to Civilization: A Comprehensive Review (1989–2013)" I read two papers published in 1993 (one of which I first read in 1993). Four authors contributed: Andy Haines, Martin Parry, Tony McMichael and Paul Epstein. These papers each used the “primary”, “secondary” and “tertiary” framework. One of them, originally read at the Royal Society of Medicine in 1992, stated “direct effects of a rise in temperature (particularly increases in the frequency and intensity of heatwaves) may include deaths from cardiovascular and cerebrovascular disease among the elderly. Indirect effects are secondary, such as changes in vector-borne diseases or crop production, and tertiary, such as the social and economic impacts of environmental refugees and conflict over fresh water supplies.” 

 

I thus realised I had unconsciously plagiarised the terms. I wrote to Prof Haines to apologise (Paul and Tony, sadly, had already died). However, between 1993 and 2010 the framework appears to have not been used in the context of climate change and health, although our paper in 2005 (with Carlos Corvalan and Hillel Koren - published in the ecology literature)  adapted it by adding a fourth scale of consequences which we called global systems failure . (It used other words for primary, secondary and tertiary, but the concepts were the same). I later self-censored this concept, as, for over a decade, I felt that it was too controversial for most reviewers and editors to appreciate, especially in health circles.

 

References

Butler, C. D., C. F. Corvalán and H. S. Koren (2005). "Human health, well-being and global ecological scenarios." Ecosystems 8(2): 153-162. 

Butler, C. D. and D. Harley (2010). "Primary, secondary and tertiary effects of the eco-climate crisis: the medical response." Postgraduate Medical Journal 86: 230-234. 

Butler, C. D. and A. Woodward (2015). From Silent Spring to the threat of a four degree world. The context of Tony McMichael’s career. Health of People, Places and Planet: Reflections Based on Tony McMichael’s Four Decades of Contribution to Epidemiological Understanding. C. D. Butler, Dixon, J., Capon A.G. Canberra ACT Australia, ANU Press: 11-30.

 

Haines, A. and Parry, M.L. (1993) Climate change and human health. Journal of the Royal Society of Medicine, 86, 707-711.  

 

Haines, A., Epstein, P.R. and McMichael, A.J. (1993) Global health watch: monitoring impacts of environmental change. The Lancet, 342, 1464-1469.

Oreskes, N. and E. M. Conway (2013). "The collapse of Western civilization: a view from the future." Daedalus 142(1): 40-58.  

Smith, K., A. Woodward, D. Campbell-Lendrum, D. Chadee, Y. Honda, Q. Liu, J. Olwoch, B. Revich, R. Sauerborn, C. Aranda, H. Berry, C. Butler, Z. Chafe, L. Cushing, K. Ebi, T. Kjellstrom, S. Kovats, G. Lindsay, E. Lipp, T. McMichael, V. Murray, O. Sankoh, M. O’Neill, S. B. Shonkoff, J. Sutherland, S. Yamamoto, U. Confalonieri, A. Haines and J. Rocklov (2014). Human health: impacts, adaptation, and co-benefits. Climate Change 2014: Impacts, Adaptation and Vulnerability, Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. C. B. Field, V. Barros and D. J. Dokken. Cambridge and New York Cambridge University Press.

Woodward, A.,K. R. Smith, D. Campbell-Lendrum, D. D. Chadee, Y. Honda, Q. Liu, J. Olwoch, B.Revich, R. Sauerborn, Z. Chafe, U. Confalonieri and A. Haines (2014)."Climate change and health: on the latest IPCC report." The Lancet 383(9924): 1185-1189.

Coal exports, development and more Australian hypocrisy

The Australian Minister for Resources, Josh Frydenberg, claimed today that Australian exports of coal to India is a "moral imperative" which will improve energy security for the poor in India, and also their health. This is, I'm afraid, either willfully deceptive or just stupidity. Unfortunately, Australian national radio then repeated Frydenberg's claim, without any countering comment.

Frydenberg should read this essay by EAS Sarma, a former secretary of India's ministry of power. Sarma points out that renewables (rapidly expanding in India) make far more sense for Indian development than Australian coal. Coal fired power stations also contribute to air pollution. Frydenberg also seems ignorant of (or indifferent to) the idea that coal exports worsen climate change, and that will also worsen the health of many people in India, starting with the poor, the same group Frydenberg professes to care about. He could also read this essay by Al Gore or this by OxFam.

There are too many other recent examples of Australian hypocrisy, such as claims that the motivation for quasi-concentration camps on Nauru and elsewhere, paid by Australian taxpayers, are humanitarian (allegedly to stop drowning at sea). Does Frydenberg think it is humane and strategically valuable to cut Australian foreign aid, because coal exports have taken their strategic place? I don't think Michael Fullilove would be so sanguine.

I am Professor of Public Health at the University of Canberra, Australia, and co-founder of the NGO BODHI, which has been trying to reduce poverty in India and other countries since 1989. I am also the only Australian IPCC contributor, to date, to have been arrested for protesting Australia's coal frenzy.

The 2015 refugee crisis and the complicity of far too many academics

What upsets me, as an academic, is that a minority of writers have been predicting things like the current refugee crisis, reflecting desperation in many developing countries since at least 1960, and yet in the 1980s they got sidelined, essentially by people loyal to a "market forces know best" view of the world. I don't know if it is now too late, or not, to change the world in ways that reduce this desperation. But a revolution within Western academic thought is needed, even if it comes too late to be of much help. Through the 1980s, 1990s and 2000s most complacent Western politicians and societies could turn, if they wanted, to mainstream academic literature which claimed that everything was getting better, via market forces. That surely has to change. "Business as usual" will not see steady improvement for most people. Fundamental changes are needed and it's a really difficult route. But more of the same is even worse.

It would be possible to assemble a collection of desperate images, but this one will suffice for now: Its shows a refugee from Guinea hiding under a car bonnet. Note that the caption in The Age likens this to smuggling from East Berlin, but that is a few kilometres. This refugee is reported as from Guinea. He may have hoped to cross thousands of kms hidden that way.

See my forthcoming blog on the "Cornucopian Enchantment" for more references, also my PhD thesis: "Inequality and Sustainability" published in 2002. See especially, Julian Simon, Bjorn Lomborg and D Gale Johnson, as examples of complacency. See Paul Ehrlich, Maurice King and Tony McMichael as counter-examples; far more rational and realistic views shared too by Frank Fenner, though Frank published little on this. See also the Rockefeller Foundation/Lancet commission on Planetary Health.

This refugee crisis could herald civilisation's collapse, but it could presage an awakening to the reality of limits to growth and the associated reality of human carrying capacity. We must not lose hope.

Arctic Ice, Maurice Newman and the arrogant dismissal of science by too many Australian elites

If any of you get the time, go to Charctic and enter the data year by year (starting with 1979) .. the trend with time is utterly convincing. Some sceptics will say - yes, but sea ice in Antarctica is increasing (even though land ice is falling) - hence climate change is wrong .. that's a bit like saying if someone's pulse is more than 100 their heart is doing ok .. (i.e. a doctor looks at the whole patient) overall, looking at the signs and symptoms of the Earth eco-social "patient" it is clear the patient is ill .. though not yet in intensive care .. if it gets to that stage then we and the next generations have had it .. after several decades of blindness to these issues the World Bank, IMF, the Vatican, the UN, and some governments are showing signs of awakening .. and new technology too .. so it's important to not lose hope - this year - the Paris meeting is very important. But as for mainstream media, even the ABC Science show, is, I'm afraid, contaminated - eg Robin Williams gave a very soft interview to Bjorn Lomborg not long ago, despite a good story about a book called the Lomborg Deception from 2010.


Maurice Newman and David Murray are prominent climate sceptics in Australia, with great influence. (Newman finally lost influence after Malcolm Turnbull's ascendancy in September 2015.) Despite their zero science background they are used to interpreting figures .. I wonder what they would make of these Arctic data? Unfortunately (back to the ABC) I have seen them hopelessly overwhelm interviewers (eg Emma Alberici) who lack the knowledge to really challenge them .. Q & A would be be vastly improved, perhaps, if they let Will Steffen (here's a link to great lecture by Will in memory of the late Michael Raupach) debate Newman and Murray - though, even there, the illiteracy of so many in the audience would be a problem .. but it would be better than having someone like Emma or Tony Jones question them.

PS the Antarctic sea ice is thought to be growing due to changed ocean circulation patterns - not any cooling in the Southern Ocean.

PPS Maurice Newman was sacked in one of the first decisions of Malcolm Turnbull's new administration.

South Asian heatwaves, climate change, development and the awakening of the great faiths to our planetary emergency

In mid-2015 there was a very severe heatwave in parts of India - soon followed by one in Pakistan. It has been worsened by its occurrence during Ramadan. The requirement for fasting during daylight hours include to abstain not just from food, but also water, though this requirement can be relaxed for health reasons.

Electricity cuts also made the Pakistani heatwave worse. The BBC reported in June that "612 people had died in the main government-run hospitals in the city of Karachi during the past four days. Another 80 are reported to have died in private hospitals." But a lot more will have died before getting to hospital - really, once at the hospital, hardly any should die .. like a lot of things from the sub-continent, this statement needs interpreting.

Heatwaves are getting worse due to climate change. In June 2015 the Lancet released a major report into climate change and health. I was invited to speak at the Canberra launch, especially on the implications for Australia from migration and conflict, but in the end couldn't. My slides, however, are available here.

Some friends in India have been affected by the heat, but I haven't heard of any that have died. But no doubt productivity has been harmed. Climate change is a slow emergency. Solutions are emerging, but one that is vastly under-recognised is of a fairer world.  Related to that is the need to reduce fertility, especially in low-income countries, not because that will slow climate change (much) but because it will promote development and reduce poverty. That will better prepare societies for the emergency that is unfolding.  The failure to recognise this is the greatest weakness in the otherwise excellent Papal encyclical on climate change, Laudato Si . The much shorter Lambeth Declaration on climate change did not mention population at all. Of interest, it was signed by representatives of several faiths, including the International Society for Krishna Consciousness, a Zoroastrian, several rabbis, a Buddhist and a Sikh.

PS. In late October a Buddhist declaration on climate change, calling for a cap below 1.5 degrees, was released.

adapted from a blog at BODHI US

Climate change as a health threat: reflections on two papers in the Lancet

This is a slightly modified and longer version of an essay I wrote for Croakey, called "Climate change a great threat to health, but not as generally conceived". In the months leading to the 2009 Copenhagen climate change conference the Lancet published an unusually long (41 page) article called “Managing the health effects of climate change”. The text postulated that “climate change is potentially the biggest global health threat in the 21st century” but the executive summary was subheaded: “Climate change is the biggest global health threat of the 21st century”. 

Later this month, in the lead up to the Paris climate change summit, the Lancet is to again publish a major report on climate change and health. I had no role in either commission, though in 20014 my edited book on the subject came out. (It is to be reprinted with a new chapter in a softcover version by mud-2016.)

From 2008 until late in 2009 I was part of a WHO-led team which was trying to update the earlier study on the burden of disease (BOD) of climate change. We eventually abandoned the project. There were several reasons for this which could become another essay – but thinking about this led me to develop a figure which those with access can view here. This link is to a poster I presented at an environmental health conference in 2013, and which was also included in chapter 26 of my edited book – it attempts to convey the future burden of disease of climate change, in about 2050.

The earlier study concluded that climate change could be attributed as causing about 5.5 million lost disability-adjusted life years (DALYs). This was mainly due to climate change-related undernutrition, with minor contributions from infectious diseases and perhaps disasters. That may sound a lot, but –even if the methodology is accepted as valid - it was less than 0.4% of the global BOD in 2000. In contrast, HIV/AIDS, the leading cause of lost DALYs in the “baseline” scenario for 2030, in an updated BOD study, contributes about 12% of the total – or a proportion about 30 times as much as that of climate change did in 2000. But climate change is a risk factor, not a disease, so it is likely to cause an increased BOD for several health conditions – such as heat stroke, malaria, undernutrition, suicide and violence. However, each of those conditions has multiple causes; weighing the fraction that climate change is responsible for is bound to be disputed. Tobacco smoke, closely followed by childhood underweight, was found to be the leading risk factors in an updated BOD study published in 2013, each causing about 8% of the total burden, or about 20 times as much (as a fraction) as that of climate change in 2000.

The claim that climate change will emerge as the greatest threat to global health this century calls for strong evidence, if it is to be taken seriously. But few health workers appear to do so; if they did, then shouldn’t health workers be arguing that resources should be diverted from hospitals, medicines and primary care in order to do so? Shouldn’t climate change and health be central to every medical school curriculum? But such appeals are far from mainstream. 

Outside health, even fewer experts are concerned, including among the agricultural and political science communities. Of course, some health workers do take this warning seriously. Here I suggest several explanations.

The first may lie with the Lancet paper itself. It is vague, repetitive, and in part overstated. At one point it comments “a 13-m rise [in sea level] would cause the flooding and permanent abandonment of almost all low-lying coastal and river urban areas. Currently, a third of the world’s population lives within 60 miles of a shoreline and 13 of the world’s 20 largest cities are located on a coast. More than a billion people could be displaced in environmental mass migration.” That sounds plausible, except that neither the IPCC nor any other authority suggests any such extent of sea level rise is likely this century. Few if any peer reviewed articles suggest more than 2 metres of sea level rise this century is plausible. While there may be reasons that even 2 m is conservative, 13 m is surely exaggerated – not that the Lancet paper suggests this is likely by 2100. In fact no date is suggested at all. A perception of exaggeration may reduce the impact of this paper, contrary to the authors’ intention.

The Lancet paper identifies six main health effects from climate change: (1) changing patterns of disease and morbidity, (2) food, (3) water and sanitation, (4) shelter and human settlements, (5) extreme events, and (6) population and migration. However, no attempt is made to rigorously quantify the health effects for any of these. I can understand why, but this risks creating a perception of “hand waving”.

Another reason for the comparative lack of impact of this paper is that although its authors are consciously inter-disciplinary, the consensus in many other disciplines is far more conservative. This is exemplified by the issue of conflict. The possibility that climate change may contribute to violent climate was first raised in the health literature in 1989 (in a Lancet editorial), but has rarely surfaced since. A recent paper, by 26authors confirms the resistance of political scientists to this idea, although, outside this discipline, the idea is gaining more currency. The 2009 Lancet paper also reviews the literature at that time concerning food security and climate change. While not quantifying the risk, the message is consistently more downbeat than that of the IPCC reports, though the 2013 IPCC food chapter is less optimistic than its predecessors. If disciplinary specialists do not share the anxiety of the Lancet authors then why should generalists?

There is another reason that neither health workers nor the wider community takes the Lancet paper’s claim seriously: general incredulity. Conceding that our species is capable of critically undermining the environmental and social determinants that make civilisation possible appears to stretch our collective cognitive capacity. While many scientists (such as Will Steffen in this excellent recent lecture on the uncharted waters the Earth system is now in) and an increasing number of lay and business people (including Elon Musk) do understand this – and are rightly apprehensive, about “business as usual” the understanding that most of the world’s population has of climate science seems not much better than of evolution a century ago, or heliocentricity several hundred years before that. Adding to this difficulty, of course, are powerful vested interests that deliberately confuse and cloud public understanding and, to an extent, inherent scientific conservatism.

The final explanation I’d like to raise here is of causal attribution, also related to cognitive biases. The late Professor Tony McMichael coined the term “prisoners of the proximate” to encourage his epidemiological colleagues to think more deeply about cause. Of course, Tony was not the first to do this; causal theory is as old as philosophy. However, despite this vintage, many people, including scientists, get stuck with their preconceptions, and many have trouble conceding not only that there may be additional causal factors, but that these may co-exist with, rather than supplant their current causal preference. This tension is obvious concerning conflict. Military theorists are happy to conceive climate change as a “risk multiplier” for conflict, but not (yet) political scientists.

Climate change can indeed be conceptualised as the most important risk to health this century, but it is only one element in a risky milieu. Lowering the risk from climate change requires reducing the risk of many of its co-determinants of civilisation health. Among these, the most important factor may be complacency.

Agriculture, inequality and poverty in India - problems with the Green Revolution

 
I just read two papers about the plight of farmers in India and nutrition. The first is in the magazine Down to Earth, called "Why Marathwada is becoming a graveyard for farmers". The second is not open access, but published in the journal Public Health. Its title is "Modern agriculture and food and nutrition insecurity: paradox in India". The second is scholarly, the first gives it a human face, starting by describing an indebted farmer who uses pesticide to commit suicide.
 
There are many interacting, interlocking factors that underlie India's poverty; some of them agricultural, some of them social. For example, the farmer who consumed the pesticide in had "borrowed Rs 60,000 from a government-owned bank and Rs 150,000 from a private moneylender. " The interest rate from the moneylender is likely to be usurious - even from microcredit schemes in India etc it is often very high (even after adjusting for inflation). The article would be strengthened by listing the interest rates.

Poor farmers are really vulnerable. There is an enormous asymmetry between them and those who are able to exploit him, such as the moneylenders. This asymmetry is not only of wealth, income, education and health, but also of information.

The part of Maharashtra discussed in this report relies mostly on rain and has been traditionally prone to droughts. Another factor in the poverty there is population pressure, which forces people to try to make a living on less agriculturally favoured areas. Yet another factor is cultural identified in the article: "They cannot take the humiliation of not being able to pay the debt or meet social obligations" - social pressure is important .. this is a cultural cause, not an agricultural cause.

Population pressure and a failure to protect the commons is also shown by the failure sufficient water.  The dam water goes preferentially to industry. Water in upstream dams are not released - this is a significant failure of governance, and a good example of the "Matthew effect" ("he who has gets"). It's a good but sad analysis - and with another El Niño declared it looks like it will get worse, at least in the next year.


Problems with the Green Revolution

The second paper is a more formal documentation of the limited evidence described in the first, from a poor part of Maharashtra. It shows how the "Green Revolution" (modern agricultural practices with high yielding seeds, intensive fertiliser and irrigation) has failed to deliver nutrition and other forms of security to the poor and vulnerable in India. The Green Revolution transformed India from a land of famines (including after it obtained freedom from British colonisation) to a net food exporter within 25 years, despite continued high population growth.  However, the paradox is that a considerable proportion of the Indian population, especially in the North, remain undernourished: surveys conducted in 2005-06 found 38% of children less than five were stunted -- with consequent cognitive impairment.

The paper in fact argues that Indian inequality has increased. Though no convincing statistical evidence of this is provided it is a reasonable assertion; in any case poverty and undernutrition (which the authors correctly attribute in part to poor health services and poor hygiene) remain at levels that should be unacceptable in a society that is more or less well governed. India (at least in its north) clearly is still not well-governed.

The paper also argues that uncritical government advocacy favoured three major cereals (rice, wheat, maize), but neglected traditional and nutritionally valuable crops including sorghum, millets, and pulses. The reduction in pulse consumption places the poor at risk of critical amino acid scarcity.

Furthermore, the reduction in (nitrogen-fixing) legume crops (especially in rotation with the main grains) has increased the demand for nitrogenous fertiliser. A combination of factors has led to aquifer depletion and soil deterioration including salinity. To this must be added high population growth (especially in the north). These are exemplify the concept that what Hardin termed as a "tragedy of the commons". (For example, if the groundwater is dropping and I fear my neighbour is taking more than his or her share, and if there is no over-lying sanction or custom to reduce my own use of the groundwater then it seems in my interest to act the same as my neighbour.) What lies ahead for India?

The authors conclude that it is vital for the new agricultural paradigm to be made truly more pro-people, including by addressing issues of poverty, gender, livelihood and environment. This cannot happen automatically without supportive government policies.

I would add that it also requires policies and a mindset far broader than most people conceive as "agriculture" - such as rural education and greater fairness in the application of laws and rules, with less discrimination against minorities and the poor.

The World Scientist’s Warning to Humanity

I leave the last word to Norman Borlaug, awarded the 1970 Nobel Prize for his role in the delivering the Green Revolution. Unlike many agricultural economists, including those who framed various world hunger targets, Borlaug and many other Nobel Laureates (including over half of those then alive) who signed the World Scientist’s Warning to Humanity. The text of this warning, one of whose signatories was Norman Borlaug, expresses far less optimism about the future than cornucopians like Bjorn Lomborg would like to believe.