Conflicting Baselines: a climate nerd winge

I find it incredibly frustrating and baffling that the IPCC and other major climate science bodies like NASA use a variety of unreconciled baselines for global temperature changes in the reports. Sometimes it is 1951-80, sometimes it is 1981-2010, sometimes 20thC average and so on.* I have not found a convenient set of translations between these baselines in the reports that would enable you to, say, add 0.4ºC to get from a 1880-1909 baseline to a 1951-80 baseline.
*Since climate averages are defined scientifically (at least by the recommendation of the WMO) as requiring a minimum of 30 years of continuous data, most baselines are 30 year periods, rather than single points in time.

Given that the UNFCCC negotiations are based on a preindustrial baseline ("hold the increase in global average temperature below 2°C above preindustrial levels", Cancun Agreement, 2010), yet have never (to my knowledge) defined precisely what "preindustrial" actually means nor attempted to quantify its relation to other baselines, it is unconscionable that the IPCC have not made this a far more prominent frame for all their work. In other disciplines, preindustrial is generally taken to mean prior to 1750 or so. One challenge of using preindustrial as a baseline in negotiations for a legally-binding international agreement is that high quality temperature data from direct measurements (rather than proxies) with good global coverage only extends back into the 2nd half of the 19thC (depending on how good you want the coverage to be). Even if the IPCC noted that estimates of global temperatures prior to the late 19thC have error bars too large for meaningful negotiations and suggested that the UNFCCC make, say, 1880-1909 the universal baseline for negotiations, that would be defensible.

One reason they haven't done so is that this would probably require a reconfiguration of the global goals away from neat round numbers, since paleoclimate specialists (who reconstruct temperature data prior to the instrumental record from proxy data) say that between ~1750 and 1880-1909 there was likely about 0.2ºC of warming. Shifting to a goal of under +2ºC from 1880-1909 would probably (and should) be resisted by those nations most vulnerable to warming.

Why does this matter? (Beyond obsessive concerns for clarity from scientists and those of us who appreciate precision)

It matters because the vast majority of journalists fail to mention (and may well not even be aware of) the issue of different baselines. The media thus regularly refers to goals like keeping temperatures below +2ºC without specifying their assumptions. Since most new scientific publications use a baseline considerably later than preindustrial, this means that many articles reporting on scientific findings give a very misleadingly rosy picture of the scale of ambition required to achieve the agreed UNFCCC target. It is much easier to meet a +2ºC from 1981-2010 target than a +2ºC from preindustrial (=~1750, or even 1880-1909) target.

And this matters because I expect that the number of parliamentarians who grasp these distinctions is also quite limited.

What path are we on? Emissions update

Between 2003 and 2008, the global economy was tracking above the Intergovernmental Panel on Climate Change's (IPCC) worst case scenario for carbon dioxide emissions. The financial crisis brought a brief respite in 2009, when emissions actually dropped (remember, this still means that greenhouse gas levels rose in 2009, just a little more slowly than they had been). But it was recently announced by the International Energy Agency that 2010 saw the largest jump in emissions in human history, putting us back up close to the IPCC worst case. What does this mean? If we continue on this trajectory, where will we end up? This piece by two climate scientists gives plenty of good context. The bottom line? According to the IPCC's most recent major report (2007), our current trajectory puts us on track for a 2100 temperature rise of 3-4°C above pre-industrial levels with likely associated impacts including:

Hundreds of millions of people exposed to increased water stress.
30–40% of species at risk of extinction around the globe.
About 30% of global coastal wetlands lost.
Increased damage from floods and storms.
Widespread coral mortality.
Terrestrial biosphere tends toward a net carbon source.
Reduction in cereal productions.
Increased morbility and mortality from heat waves, floods and droughts.

Remember that these projections are based on IPCC AR4 (2007), which was a compilation of research up to the middle of last decade. A lot has happened in climate science in the last five or six years, and little of it has made the picture any rosier. Crucially, the above projections do not include a variety of feedback mechanisms that were not well understood at the time of publication. And there have also been advances in modeling likely impacts in some areas, notably, sea level rise, which is now thought to be between 0.5 and 1.5 metres by 2100. Of course, if our emissions are towards the upper end of the scenarios, then rises are also likely to be higher than 50 cm. However, I think that it is reduction in cereal production that could be the most significant effect geopolitically in the next few decades.

For a more up to date assessment of the state of the science, see the recent Australian Climate Commission's publication The Critical Decade, whose three chapters are helpfully summarised by Skeptical Science: one; two; three. Here is the concluding paragraph:

As you’ve read in this report, we know beyond reasonable doubt that the world is warming and that human emissions of greenhouse gases are the primary cause. The impacts of climate change are already being felt in Australia and around the world with less than 1 degree of warming globally. The risks of future climate change – to our economy, society and environment – are serious, and grow rapidly with each degree of further temperature rise. Minimising these risks requires rapid, deep and ongoing reductions to global greenhouse gas emissions. We must begin now if we are to decarbonise our economy and move to clean energy sources by 2050. This decade is the critical decade.

Remember, we are not just talking about less ice or a few more days of sunscreen, the likely geopolitical consequences of our current path are dire. It doesn't have to be this way.

Climate change contributing to rising food prices

Study links climate change and rising food prices, as I suggested back here, here, here and here. The study argues that changing weather patterns have held back the growth in global food production by around 5%, contributing about 20% of the recent doubling of prices (which also have other causes).

BBC: Nitrogen pollution estimated to be costing £55 billion to £280 billion annually in Europe alone.

Guardian: How to tell the difference between the rule of law and a police state in the light of Ian Tomlinson, the protester unlawfully killed by police and the subsequent alleged cover up.

Common Dreams: This is what resistance looks like.
H/T Matheson.

Paul Gilding: The great disruption arrives. Different authors use a variety of phrases to speak of the converging ecological and resource crises facing humanity: the great emergency, the long descent, Eaarth, planet triage, the Anthropocene, the great acceleration and so on.

Intergovernmental Panel on Climate Change (IPCC) releases a new report that finds up to 77% of global electricity primary power generation from renewable power by 2050 is both technically and economically feasible. The primary barriers are political.

Guardian: Why supermarkets are odious. We are blessed with a weekly farmers market a few hundred metres from our door, and have a deal with a local farm to receive a box of fresh produce each fortnight. Even so, it is hard to avoid supermarkets entirely.

SMH: How much does an iPad really cost? Although Apple are far from the only company with shady production conditions, they are the largest and were recently fingered as also having the worst ecological record, so highlighting their failure is legitimate. These conditions are not inevitable. Companies could be held responsible for the full life-cycle of their product, which would provide a significant incentive to shift design assumptions away from built-in obsolescence (which is currently the industry standard). It is also worth noting that many of these pieces of equipment are not just bad for the workers who produce them and the ecological systems on which we all rely for life, but can be part of the shrinking of the consumerist soul into finding an identity and satisfaction in what is bought and consumed.

Guardian: In a secret deal between Pakistan and the US, agreed in 2001 and renewed in 2008, Pakistan allegedly agreed to unilateral US strikes as long as they were allowed to publicly decry them afterwards. I don't think that this kind of agreement is conducive to healthy international relations in the long term, as it undermines trust when parties are revealed to be dissembling.

And because I haven't raised enough controversial topics in this post yet, I thought I'd mention this new study of more than ten thousand children that found that breast feeding is linked to fewer behavioural problems.

Another exoneration: IPCC head cleared of financial wrongdoing by KPMG

To go along with the recent string of exonerations that have been given by public enquiries concerning the hacked CRU emails and the vindication of Michael Mann's conduct by PSU, now accusations of financial impropriety made against Dr Rajendra Pachauri, chair of the IPCC, have also been refuted in an investigation by KPMG. The Sunday Telegraph, which first broke the story, has removed it and offered an apology.

Dr Pachauri has received a sum total of £0 for his work as IPCC chair (yes, far from a socialist plot to install world government, the IPCC is a tiny group co-ordinating the work of thousands of scientists that can't even afford to pay its own chair). And his entire income is under £50,000. More details are found here, with intelligent discussion here.

But like all such retractions, it is too little, too late. The smear did its job, spreading popular doubt about the work of the IPCC around the time of increased global attention on the issue due to the Copenhagen conference.

Yet of all the accusations against climate science flying around at the end of last year, the worst that have been substantiated were a reference to an incorrect date on one page of the IPCC's 2007 report (which ran to thousands of pages), some personal nastiness in private emails and possible evasion of FOI requests by a scientist under siege from dozens of such requests. No consensus has collapsed, no climatologists have been shown to have been fraudulent, no studies have been fatally undermined, no new theory to explain the data has gained wide acceptance. It is still the case that over 97% of the most active climatologists agree that human emissions are the primary culprit for a significant and ongoing rise in global temperatures and shift in climate patterns.

Moral: don't believe every breathless scandal dished out by the popular media, especially when the source is a blogger with an unimpressive track record and the target is a highly politicised figure. But then, most of you knew that already.

Weather vs climate

There is an important and often misunderstood distinction between weather and climate.

Weather is what is happening when you go outside. It is what meteorologists study and consists of dynamical systems that are highly sensitive to initial conditions driven by the movements of blocks of hot and cold air. It is measured hour by hour (or even minute by minute) and predicted a few days in advance, beyond which the complexities and sensitivities of the system make computational estimation almost impossible.

Climate refers to long term patterns of weather. It is what climatologists study and consists of dynamical systems driven by long term fluctuations in solar activity, oceanic currents, surface albedo and atmospheric chemistry (and, over the very long term, by geological forces and plate tectonics). It is measured in decades, centuries and millennia and predicted in decades.

Predicting the climate
Yet this raises a common question: if we can't predict next weekend's weather, how can we predict the climate in 2050? Remember that climate prediction doesn't mean a prediction of weather, on which day it might rain or be a certain temperature at a given location. It means predicting the overall pattern, which, while chaotic from week to week, fluctuates within a certain range over the long term. Climate prediction means predicting changes in that range within which weather might fluctuate.

Imagine a pot of water being brought to the boil. Although predicting exactly where and when a bubble will appear is almost impossible, it is still quite possible (given knowledge of the original temperature and volume of the water and the amount of heat energy being applied) to predict when it boil with some degree of accuracy. Or consider tossing a coin one thousand times. It is almost impossible to know whether any given toss will be heads or tails, but we can all predict that there will be about five hundred of each. Or think of sitting on a packed train. You mightn't be able to guess how the person next to you is likely to vote in an election, but with knowledge of quality polling data (if that is not an oxymoron), you can make a pretty good estimate of the likely distribution of votes on the train as a whole.

So climate and weather are closely related, but it is important to keep their distinction in mind. One way of putting it I heard recently is that climate trains the boxer, the weather throws the punches.

This distinction means that it is not possible to directly attribute any particular example of weather either to anthropogenic climate change or to natural variation. A cold day doesn't disprove the theory any more than a hot day proves it. Each are a tiny piece of evidence in a much, much larger pattern. And when an extreme weather event comes along (such as the current Russian heat wave and Asian floods), this too doesn't by itself prove anything. What does count, however, is the well-recorded pattern of increasing frequency and intensity of such events. Put simply, climate change doesn't cause extreme weather, but it increases the chances of it happening, and increases the extremity of what is possible. This is because warmer air can hold more water, bringing more intense precipitation. By the way, this includes more intense snowfall if the temperature happens to be below freezing, as was seen in the northeastern US earlier in the year. Or as NASA says, this is what global warming looks like.

Read more

Climate science vindicated again

A couple of hours ago the Muir Russell inquiry into the hacked CRU emails was published. Here are the key findings from the executive summary (emphases original).

13. Climate science is a matter of such global importance, that the highest standards of honesty, rigour and openness are needed in its conduct. On the specific allegations made against the behaviour of CRU scientists, we find that their rigour and honesty as scientists are not in doubt.

14. In addition, we do not find that their behaviour has prejudiced the balance of advice given to policymakers. In particular, we did not find any evidence of behaviour that might undermine the conclusions of the IPCC assessments.

15. But we do find that there has been a consistent pattern of failing to display the proper degree of openness, both on the part of the CRU scientists and on the part of the UEA, who failed to recognise not only the significance of statutory requirements but also the risk to the reputation of the university and, indeed, to the credibility of UK climate science.

The full text (120 pages) is here. This is basically what I said back in November and confirms the earlier two inquiries into the CRU emails and also stands with the two-part PSU inquiry into the conduct of Michael Mann, who was also decisively vindicated. Claims of a whitewash need to take this into account. This latest finding also needs to be put together with a recently published Dutch review of the IPCC 4th report, which found only minor faults.

If this all makes no sense to you, then you are fortunate for not having been following the media circus over the last few months. If you don't believe a word of any of these independent vindications of climate science, then perhaps you need to think about the nature of conspiracy theories. If you're wondering why this even matters, it is because what we do with what we know is important.

Making a mess is easier than cleaning it up

A major UK paper has been forced to retract an article filled with false smears against the IPCC and climate scientists. The so-called "Amazongate" scandal was a complete beat-up (like much of the woeful mainstream coverage of climate "scandals"). Basically every claim in the article was acknowledged as false or misleading. The real scandal was not found at the IPCC, but in a media and blog world where such claims were immediately picked up and echoed on literally thousands of sites. Ironically, the accusation levelled at the scientists (making claims based on unsubstantiated sources) was actually only true of the journalists and bloggers who repeated it.

The Sunday Times only made the embarrassing retraction when one of the scientists blatantly misquoted and slandered in the article complained to the UK's Press Complaints Commission.

The sad thing is that each step of the process of complaint, investigation and correction probably used considerably more time, energy and money than the original investigation and publication. Misinformation is much, much easier to create than to clean up. Much like oil spills, I guess.

Freed to love: why (rich) Christians need to think about climate change

For you were called to freedom, brothers and sisters; only do not use your freedom as an opportunity for self-indulgence, but through love become slaves to one another. For the whole law is summed up in a single commandment, ‘You shall love your neighbour as yourself.’

Galatians 5.13-14.

Freedom is ordered towards love; we are free in order that we might love, and in love become slaves to one another. Christian liberty is the freedom to do good to my neighbour. Central amongst the goods I might do for my neighbour is echoing the divine call to enter into this very freedom to love. And so part of my free service will be inviting my brothers and sisters into the service of those around them: "Let us serve our neighbours and do good to everyone, especially to the household of faith!"

Yet this service is not exhausted by issuing such an invitation. There are many other ways of serving one another as well as proclaiming the good news of freedom in Christ. To be of service to my neighbours, some of the good things I can do will require more specific knowledge of my neighbours and their condition and context. Do they need food? Do they need to learn how to fish for themselves? Do they need to have their fish stocks protected from illegal fishing? Do they need medical aid? Do they need a healthcare system that delivers better care? Do they need a friend they can trust? Do they need a society in which trust is prized and protected? What fear or guilt is oppressing them? Is a fearful society confusing their ability to discriminate between threats? Are they a victim of crime? Is corruption undermining the rule of law in their community? Are they addicted to self-destructive behaviours? Does their society encourage them towards the idolatry of greed? Towards superficiality of judgement? Does their lifestyle (and that of their society) contribute to reducing the freedom of others to love and serve?

The answers to these questions will not be easy or simple. They will not be found only by studying the scriptures (though that will of course be part of it!). To love our neighbour, we have to pay close attention to the world and how it works, including the disputed areas.

At stake is the relation of knowledge to ethics. Saint Paul prayed that the Philippians’ love would "overflow more and more in knowledge and depth of insight" - knowledge of God and the good news of Jesus, yes, but also knowledge of one another and the world in which they are called to love. We cannot love our neighbours without some attempt at understanding them, their history and gifts, their situation and the world which we share, including its threats and possibilities.

For example, Christians amongst areas ravaged by AIDS will need to come to an opinion about whether HIV leads to AIDS or not (this is hotly contested in parts of Africa, and there are campaigns against the use of retro-viral drugs, and shoddy pseudo-scientists throwing mud into the air). Christian parents will need to come to an opinion about the benefits and costs of immunisation (where again, confusing signals have often been sent by the media based on poor scientific work). And Christians with influence in energy, in public policy, or those with carbon-intensive lifestyles and with global neighbours who live in drought or flood-prone areas will sooner or later have to have some kind of opinion on climatology and carbon.

Not every Christian is able or obliged to answer every conceivable question about how to love our neighbours, or to evaluate the variety of threats and opportunities we focus upon. But Christians do need to think carefully about which sources of knowledge are trustworthy, and what we do with that knowledge. Will we trust the IPCC and the national scientific bodies of thirty-two nations when they tell us they have over 90% confidence that human activities (particularly those in developed nations) are significantly contributing to changes with very serious negative effects now and increasingly into future decades (particularly on the world's poorest peoples)?

God doesn’t give us an exhaustive list of who we are to trust and how far. But that doesn’t mean the question is morally irrelevant or that refraining from the discussion is the best use of Christian freedom to love. This may not be the only or the greatest moral issue of our time, but it is a very significant one.

Christian freedom does not mean that we are released from the responsibility to consider carefully the effect that our habits, actions and beliefs have on those around us. Quite the opposite: we are liberated from the intolerable burden of having to save ourselves or our world, and given many opportunities to do all kinds of good. Let us use our freedom in order to love.

On errors in the IPCC report

I had been thinking recently about addressing this question, which has been much in the media, since it relates to what we do with what we know. But I have just come across this excellent open letter, signed by over 250 scientists (nearly all active in research and publication in climatology and other closely related fields and working in top US universities and institutions), which sets out the issues very clearly and with much insight. It is worth reading in full, particularly if you have got the impression from recent headlines that climate science is in some kind of crisis of credibility.

UPDATE: In Australia, the Bureau of Meteorology and the CSIRO (Australia's top two climate science institutions) have recently released a six page PDF summarising the state of Australia's climate: rising CO2 and methane, rising average temperatures, rising numbers of record hot days, falling numbers of record cold days, rising sea levels, rising ocean acidity, shifting precipitation (including falling precipitation across the vast majority of populated areas) and some very brief discussion of what we can likely expect to lie ahead.

Futher update: Here is an excellent sober discussion of the extent and significance of the mistakes by an expert in the field.

Jesus and climate change II

The Intergovernmental Panel on Climate Change (IPCC) is the peak body on the science of climate change. The IPCC recently released the fourth part of its fourth report, which are completed every four years. This fourth document is publicly available (here is the Summary for Policymakers) and integrates the findings of the previous three sections published earlier this year. Here are some of the key findings (adapted from an SMH article I now can't find, though I also note it is here):

What's happening?

• Evidence for global warming is now “unequivocal”, and there is a more than 90 per cent probability of human responsibility for the problem. The main culprit is carbon gas emitted by burning of fossil fuels, which lingers in the atmosphere and traps solar heat.
• Since 1900, the mean global atmospheric temperature has risen by 0.8 degrees Celsius and the sea level by 10-20 centimetres. Eleven of the past 12 years rank among the dozen warmest years on record.
• Human-generated greenhouse gases rose by 70 per cent between 1970 and 2004 from 28.7 to 49 billion tonnes per year in carbon dioxide or its equivalent. Levels of carbon dioxide, the main greenhouse gas, have risen by about a third since pre-industrial times and are now at their highest in 650,000 years.
• Climate change is already happening, visible in the loss of alpine glaciers and snow cover, shrinking Arctic summer sea ice and thawing permafrost.

What are the likely implications?

• By 2100, global average surface temperatures could rise by between 1.1 and 6.4 degrees compared to 1980-99 levels. But this average rise will mask big variations, according to region and country.
• Within this range, "best estimates" run from 2.4 degrees for a scenario based on a major switch to non-fossil fuels and 4 degrees for a fossil-fuel intensive "business-as-usual" scenario.
• Sea levels will rise by at least 18 centimetres by century's end. There is no estimate for the upper limit, given the unknowns about the impact of warming on ice sheets in Greenland and the Antarctic.
• Greenhouse-gas warming “could lead to some impacts that are abrupt or irreversible”. The risks are related to the rate and magnitude of the climate change.
• 20-30 per cent of plant and animal species are threatened with extinction if average global temperatures increase by 1.5 to 2.5 degrees, compared with the average temperature 1980-99. With a 3.5 degree rise, this rises to 40-70% of all plant and animal species.
• “All countries” will be affected, especially poor tropical countries struggling with water stress and few resources.
• In Africa, by 2020, 75-250 million people will be exposed to increased water stress. Yields from rain-fed agriculture in some African countries could be reduced by up to 50 per cent. Desert-like areas could expand by 5 to 8 per cent by 2080.
• In Asia, available fresh water will decrease by mid-century. Coastal mega-deltas will be at risk from flooding due to rising seas. Mortality due to diseases associated with floods and droughts will increase.

What can be done?

• To stabilise emissions at levels likely to limit the overall rise to 2.0 to 2.8 degrees would cost less than 0.12 percentage points of annual world GDP growth to 2030.
• A "wide variety of policies and instruments" exist to reduce emissions, including carbon taxes, tougher emission standards, caps on emissions, incentives for clean energy production.
• In addition to emissions mitigation, a huge effort is also needed in adaptation, to channel funds, technology and knowledge to poor countries that will suffer disproportionately from climate change.

Series: I; II; III; IV; V; VI; VII; VIII; IX; IX(b); X; XI; XII; XIII; XIV; XV.

Would Jesus vote green? V

Scepticism (cont)
And yet, scepticism alone is inadequate. There is a place for reserving judgment, but there is a point where to continue to do so in the face of overwhelming and pressing evidence is simply stubborn. How much scepticism is too much? There are such things as foolish gullibility and lazy conformism, but there also comes a time when stubborn scepticism tips into basic disconnection from reality.

I am fairly sure that of the statistics I quoted, some are probably inaccurate, and some may be based on faulty methodology, or outdated research. I am no expert and am quite happy to be corrected, yet it seems to me that it is now impossible to reasonably deny that human activity is indeed having a significant detrimental effect upon the living spaces of the planet. To do so is an exercise in wishful thinking. And this is no surprise to Christians, as we shall see.

For instance, while there is still dispute over details, to continue to suppose that human activity has not been a major cause of global climate change places you in disagreement with every major scientific organization in the world – except the American Association of Petroleum Geologists. As far as I am aware, for about the last ten years there has not been a single peer reviewed scientific publication disputing the human causation of recent global climate change (please link to examples if you know of any, I could be wrong, but this is what I've heard).

Yet there are still large numbers of people who continue to deny this claim in the face of almost unanimous consensus amongst the scientific community. At some point, it is right to become suspicious of such sustained denial, asking whether it mightn’t be a coping mechanism for dealing with hidden grief or guilt. Denial is a common part of responding to serious tragedy, but to properly grieve, we need to move beyond it. If you call yourself a skeptic,* I hope that in the following posts, you’ll discover reasons why it is safe to move beyond systematic denial.
*Not simply about climate change. I realise that this issue in particular has become highly politicised. At the moment, I am more interested in the broader claim about detrimental human effects on the environment considered more broadly. Nonetheless, here is a useful site answering 26 common myths about climate change. H/T OSO.
Thanks also to the Social Issues Briefing #63 for some of the thoughts in this post. Read it here. If you'd like to receive it regularly, sign up here.
Series: I; II; III; IV; V; VI; VII; VIII; IX; X; XI; XII; XIII. Photo by Steve Chong.