“It is therefore inappropriate to present type 4 results to the impacts community as reflecting more than a subset of possible future climate risks.”

The article refers to a recent study by Pielke et al. (2012) which states:

“Neither dynamic downscaling or statistical downscaling from multi-decadal global model projections add proven value to spatial or temporal accuracy that can assist the impacts community in ways beyond what is already available from historical, paleo- or analogue records”. [emphasis in original]

The latter quote poses a direct challenge to the regional climate modelling community, some of whom reside here in CSAG. I’d certainly be interested in hearing the responses of those actively involved in downscaling activities. However, at risk of offending and/or appearing to pander to my colleagues, in this blog I address the former quote; a cowardly but, I hope you agree, sensible decision.

If climate scientists are only able to offer “a subset of possible future climate risks” then modelling centres really can’t purport to be offering climate predictions, on multi-decadal or longer time scales. This isn’t a wholly controversial point however. Indeed the IPCC and most modelling centres disseminate information about future climate in the form of projections, rather than predictions or forecasts. Nevertheless, do users fully appreciate the nuanced language of climate scientists? Moreover, do climate scientists fully appreciate the often far-from-nuanced interpretation of climate model projections?

The Ensembles project website offers a nice explanation of the difference between the terms prediction and projection. However, climate scientists aren’t always that careful when it comes to the separation of these terms. Even the UK Met Office is guilty. In their guide to climate change on their website, they carefully explain that climate models are used to make climate change projections. So far so good. Yet in the following section, they include animations showing “predicted” temperature rise up to 2100. Now this is either sloppiness on the part of the website editors or they really do predict temperatures will evolve according to the animations shown; of course the animations are emissions scenario dependent so that gives them a good get out if emissions follow a different path.

I am not convinced distinguishing between the terms projections and predictions really communicates the full story. Perhaps instead of using the word projection, consistent with the concluding statement of Pielke Sr. and Wilby (2012), we ought to refer to the output of regional climate models as climate possibilities. This seems, at least to me, a better way to articulate what we actually mean. The word projection implies some kind of expectation that the climate system will act in a similar way to the model whilst the word possibility implies that there is a chance the climate system will behave in a similar way to the model but equally that there is a likelihood the system may do something entirely different.

In the scientific discourse on climate modelling I have no problem with the use of the word projection. It is an accurate term to describe what a model is doing: projecting the dynamic behaviour of the climate system within a model domain. However, when we want to express how model projections relate to the real climate system, extending the use of the word projection may be misleading, particularly when such projections are being used to guide real-world policy decisions. Climate models are mathematical approximations to the climate system, they are not (and never will be) isomorphic to the real climate system. What is possible in “model world” may not be possible in the real system and vice versa. Therefore we must be wary about overstating our confidence regarding the behaviour of the real climate system based on model predictions, projections and even possibilities. I feel impelled to qualify that statement by saying that models are still valuable tools and essential for guiding climate change adaptation and mitigation policy. We would be foolish to dismiss model output because of model inadequacies and therefore ought to view the output as possible until proven otherwise.

In any case, I suspect climate modelling centres won’t start issuing “climate possibilities”. It certainly doesn’t have the same pizzazz as “climate projections” and given ever increasing pressure to provide policy-relevant climate science, simply saying “the models indicate a range of future climate possibilities” sounds like an admission of ignorance and creates an impression that climate scientists really don’t have a clue what to expect. Using the language of possibility also raises the troubling prospect of having to consider the inverse. Are we confident enough to profess that certain future climate states are, in fact, impossible?

A recent article on the BBC website highlights the current growth and potential future plight of the rooibos industry. The article states:

Rooibos is particularly vulnerable to changes in the weather as it only grows in about 20,000km sq of the Suid Bokkeveld due to the region’s biodiversity. The herbal plant needs specific bacteria and fungi to be present in the soil as well as certain bees and wasps which are only found here.

Archer et al. (2008) examined the adaptation responses of rooibos farmers during a partcicularly dry period from 2003 to 2005. The authors noted that the Suid Bokkeveld region experienced “a 40% decrease in cultivated rooibos yield for the 2004/5 season and decreased yields for farmers as a result of a severe dry spell in July 2005.” The study concludes that the farmers have substantial experience in adapting to adverse climatic conditions but to address climate change, additional adaptation measures may need to be implemented.

I do not wish to trivialise the nature of the threat facing those who are reliant on the success of the rooibos plant. The additional pressures that climate change may place on an already drought-sensitive industry may have disastrous impacts on the livelihoods of rooibos farmers. However, my personal worry about the possible demise of rooibos (which thankfully is by no means certain) reminds me that despite my best efforts, I tend to be more interested in the negative impacts of climate change when I can see a direct, albeit minor, impact on my own way of life. I suspect I am not alone. I also only worry about the possible negative impacts of climate change rather than look forward to the positive impacts. Maybe I am too easily influenced by scare stories in the media or maybe it is because the negative impacts far outweigh any benefits. The IPCC assessments certainly seem to support the latter.

Over the coming century society will encounter both positive and negative impacts of climate change. Our perceptions of what constitute a positive or negative impact are however dictated by our vulnerabilities, interests and values. For example, the observed and projected shrinking of the Arctic sea-ice is likely to be welcomed by multi-national companies hoping to reduce the costs of shipping but feared by those living in northern latitudes who have economic and cultural attachments to the presence of sea-ice. This example illuminates an interesting social dimension to perceptions of climate change impacts. We tend to be suspicious of those who position themselves to take advantage of climate change and supporting of those who are threatened. Adaptation to climate change needn’t always be focused on reducing risk; strategies can also be developed to exploit opportunities.

Having been exposed to climate science research for a number of years, I can say with some confidence that there is a tendency to focus on the negative impacts of climate change within the research community. Conversely for those researching sustainable development, climate change is becoming increasingly framed in relation to opportunities which ought to be exploited. Job creation, energy security and technological innovation are often cited examples of the benefits of addressing climate change by shifting away from a fossil fuel economy. Should the climate change impacts research community be placing more emphasis on the possible benefits and opportunities associated with climate change impacts over the coming decades? Can we simultaneously support measures to reduce greenhouse gases whilst actively pursuing research into the benefits of climate change which may be exploited by appropriate adaptation? Unlike Bjorn Lomborg, I am not advocating a reduction in our efforts to address the projected negative consequences of climate change but I wonder if we are missing a trick by not placing more emphasis on the benefits that may accompany a warming world.

“Climate” has no single definition which is unfortunate in the world of science and academia as it means scientists regularly talk over each other. I hope to write a blog shortly on the multiple definitions of climate, and more importantly why they matter, but I want to maintain focus for now on why we should not treat the current state of the atmosphere, ocean and other components of the climate system, as simply noise in relation to climate change. Moreover, I hope to convey that the initial state of the climate system (as observed temperature, pressure, humidity fields etc) is surely relevant for climate prediction on all time scales.

Initialisation of climate model experiments is seen as an essential component of improving decadal forecasts but why stop at decadal forecasts? Traditionally, climate change has been viewed as a boundary condition problem. However I struggle to understand the logic that because the fractional proportion of uncertainty decreases relative to other sources of uncertainty such as model error and the future GHG emissions scenario (Hawkins and Sutton, 2009), it is less important to consider initial conditions in projecting climate change at long prediction lead times. Less important for what? Are we less interested in the range of future states consistent with the climate system under different forcing conditions? It is no doubt important to continue improving the reliability of climate models and perhaps (if possible) reduce our emissions scenario uncertainty but we cannot do this at the expense of the very thing we are interested in: climate under climate change.

This blog was spurred by a recent publication by Miller et al. (2012) which provides evidence suggesting that the Little Ice Age (LIA) was initially triggered by volcansim and maintained for many centuries by a sea-ice feedback mechanism. The authors state:

“Increased sea ice export may have engaged a self-sustaining sea-ice/ocean feedback unique to the northern North Atlantic region that maintained suppressed summer air temperatures for centuries after volcanic aerosols were removed from the atmosphere…The persistence of cold summers is best explained by consequent sea-ice/ocean feedbacks during a hemispheric summer insolation minimum; large changes in solar radiance are not required.”

We can extract some important lessons about how we can best utilise models to forecast the future climate. Firstly, understanding how feedbacks in the climate system operate and ensuring models can recreate such feedbacks is an essential component of the climate forecasting problem. Secondly, determining the likelihood of such feedbacks being triggered requires a systematic appraisal of possible triggering mechanisms. The reason I am addressing initialisation of climate models here is largely in relation to the second point. Consequently, I present a hypothesis: the persistence of cold summers during the LIA was both a function of the underlying boundary conditions and the initial state of the climate system. If follows that for another initial state, the triggering of the sea ice feedback and the subsequent persistence of the LIA may not have occurred.

To test this hypothesis, we need to enter the world of chaos. The presence of chaos (broadly defined as sensitivity to initial conditions) is well known to place a limit on the accuracy of deterministic model predictions for global atmospheric circulation, which is in the order of two weeks and explains why a weather forecast beyond a few days is highly speculative. Yet the return of the seasons (related to Earth’s orbit around the sun) and the controlling influence of the oceans makes climate forecasting a possibility. This does not however mean that chaos is irrelevant to climate forecasting. Rather we become more interested in the presence of chaos in other more slowly evolving sub-systems of the climate which ultimately constrain the behaviour of the atmosphere: the ocean and cryosphere etc. There are some pretty big unresolved theoretical questions here relating to concepts such as ergodicity, transitivity, and coexisting attractors. The pioneering work of Edward Lorenz which explored the role of chaos in weather and climate prediction is still an active area of research today. However, the scope of this topic is a bit too large to begin dissecting within this blog post. Rather, I would simply like to illustrate the relevance of pursuing research to better understand the impact of initial conditions in climate forecasting.

One model run won’t give us a very good idea of what the model climate is under climate change. It will simply tell us what the particular model version does for a particular initial condition. To understand how models treat climate as a distribution of possible states consistent with a particular forcing scenario, we need to run large initial condition ensembles which are initialised within the uncertainty in the current state of the climate system. Some progress is being made in this area utilising the climateprediction.net platform. A project titled weatherathome is running for the southern African region to investigate possible climate system trajectories from multiple initial conditions. This project could result in some pretty illuminating results addressing intriguing questions such as, “what weather could have been experienced in the 1961 to 2010 period in southern Africa had the initial state of the system been slightly different?” Personally, I think this is a positive and much needed step for the climate modelling community if we are to make progress in understanding past, current and future climates under climate change.

To conclude, the goal of climate prediction should not be to improve the “skill” of climate forecasts as measured by improvements in the ability to reproduce traditional climate variables such as global mean temperature (see previous post). We may well be able to improve skill yet continue to provide forecasts that are woefully inadequate to inform societal decision making. Therefore the goal should be to provide forecast information that can is useful to decision makers. I struggle to see how initialisation of models can be deemed relevant for weather forecasting, seasonal climate forecasting and now decadal climate forecasting but irrelevant for long-term climate forecasts aimed at providing guidance for climate change adaptation.

Following a very interesting dissection of the COP 17 outcomes at an ACDI event held earlier this week at UCT, one of the apparent successes of the Durban meeting was the progress made on adaptation. The UNFCCC is giving increasing attention to the issue of how to adapt to climate change and established the Adaptation Committee as part of the Cancun agreements. My day job is to understand how climate information can best be communicated and used to inform climate change adaptation decisions so clearly I agree that adaptation is important. In fact, the short-term benefits of adaptating to climate variability and climate change in vulnerable parts of Africa far outweigh the short-term benefits of any mitigation agreement; of course over time the benefits of a comprehensive emissions policy becomes increasingly beneficial. However, I thought the mission of the UNFCCC was to “prevent dangerous human interference with the climate system”. Any progress on adaptation is really just an attempt to hide the miserable progress being made on the fundamental issue of emissions reductions. We can’t afford to “pat ourselves on the back” by coming up with solutions to problems of a different nature.

Now I recognise that the wider remit of the UNFCCC does indeed include an objective to launch national strategies to address climate change adaptation but I don’t think it is helpful to point to progress on adaptation to accredit success to the UNFCCC. Indeed adaptation and mitigation policy strike me as two very different beasts. Contrary to one of the comments from an audience member who stated that in the context of sustainability “mitigation and adaptation are the same thing”, it is important to recognise the very different objectives of mitigation and adaptation policy. In IPCC language, adaptation is an “adjustment in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities”. No where in this definition does is suggest that adaptation should necessarily be green. Air conditioning is an obvious example of how adaptation to climatic stimuli need not be carbon friendly. Indeed if the goal of the climate negotiations was to enable humans to adapt to whatever climate zones we wish to live in, we might all choose to live on the beach near an air-conditioned, indoor ski resort (see picture for the ski resort in Dubai!). Clearly we need to avoid adaptation that is maladaptive, such that it leads to greater emissions, but also it is important that the forum in which adaptation is discussed reflects the different information required to enact policy and brings together the appropriate stakeholders.

…so what message am I trying to communicate for how we address adaptation policy at an international level? Well this comes back to another sentiment that was shared by many people at the meeting. We need to ensure that in making policies, the right people are in the room. In the UK, the Department for Energy and Climate Change (DECC) really has very little to do with adaptation; this work is the largely the responsibility of Defra (Department for environment, food and rural affairs) and the Environment Agency. At a national policy level, in the UK at least, this differentiation seems to work. Why then does the UN want to address both mitigation and adaptation in the same conference, under the same framework agreement? Surely the fact that they are both climate issues is not a reasonable justification. The reason I worry is that in setting legislation to guide African nations (and indeed nations on other continents) in addressing climate change adaptation, we need to ensure the people in the room are indeed the right people. The danger of combining mitigation and adaptation policy discussions within the same forum is that misinformed policies will result and action on adaptation will be weaker.

Fortunately, I am not paid by CSAG to make predictions regarding the chances of a record global temperature in 2012. Instead I can resort to the relative safety of speculating what 2012 might bring for the world of climate change policy and climate science research. The centerpiece of the 2012 conference calendar is the Earth Summit 2012 (or Rio+20) meeting to be held in Rio de Janeiro in June. The issue of climate change and how the UN has managed climate negotiations over the past twenty years since the 1992 Earth Summit is sure to be high on the agenda. It is not clear whether or not heads of state will be attending the meeting in Rio but those interested in climate policy, and particularly the future of the UNFCCC, will be keeping a close eye on developments. As a pre-cursor to the Earth Summit 2012, a conference titled “Planet Under Pressure” will take place in London in March. The conference aims to “provide a comprehensive update of our knowledge of the Earth system and the pressure our planet is now under“. It is hoped that researchers and businesses will come together at this conference to showcase sustainable solutions to combat the various environmental challenges that we are faced with and generate a sense of optimism which can encourage policymakers at the Rio meeting to be ambitious in committing nations to address global sustainability issues. I will be attending the London meeting so keep an eye on this blog for updates during the conference.

For climate scientists, 2012 offers another opportunity to submit scientific contributions for the latest IPCC report. The deadline for Working Group I contributions is July 31st but those working in impacts, adaptation or mitigation solutions can relax as the deadline for Working Group’s II and III isn’t until January 31st 2013. Here at CSAG, we are hoping for much better representation from African research institutions in the AR5 report compared to previous assessment reports. One of the aims of the CORDEX project is to produce a number of papers regarding African regional climate change information for inclusion in the AR5 report to provide a sound scientific basis for supporting adaptation decisions across Africa. A paper writing workshop will take place here in Cape Town at the end of February to enable authors from different institutions to come together and work on their contributions.

Finally, as is traditional before Christmas, the year will end with a gathering of negotiators repeating the words “urgency” and “common but differentiated” at the annual UN COP meeting. The big question everyone is asking this year is what on earth they will call the inevitably meagre policy developments made in Qatar. My money is on either the “Doha Dossier” or the “Doha deliverables”. Any other suggestions?

CSAG participated in a number of side events at the recent COP 17 meeting in Durban. A climate change decision game featured in three of these side events. Although each event had a different focus, the outline of the game remained consistent for each audience. The game relied on the active participation of delegates at the COP meeting and was developed to communicate two key messages. Firstly, decisions regarding climate change adaptation are sensitive to multiple and often conflicting sources of information which are rarely, if ever, limited to climatic factors alone. Secondly, and perhaps of more relevance to the developing climate services agenda, the precise manner and form in which climate information is communicated can effect the eventual decisions that are made. It should be highlighted that much of the effort that went into designing and running the game can be attributed to Chris.

The Game

Each member of the audience assumed the role of a local authority planner for a predominantly agricultural area in southern Zambia. In this role each individual had to consider the possibility of increasing drought frequency and/or severity resulting from climate change. The audience was told that a once-off offer for $5 million had been made available by a donor to match an investment of $5 million from the local authority budget to build of a dam and irrigation system as an adaptation response; this adaptation response was deemed to be the most appropriate available response (a contentious issue in designing the game but we proceeded nonetheless). Given various sources of information, each individual then had to decide whether or not to go ahead and invest in the dam and irrigation system.

There were six stages to the game. In each stage, the audience was presented with different pieces of information which were relevant to the decision. Most of the information was related to climatic factors such as rainfall observations and temperature projections but some pieces of information concerned social and cultural elements. The information was extracted from various climate decision portals in addition to links from a Google search and the personal views of “experts”. After each stage the audience members had to decide whether they would vote “YES”, “NO” or “I NEED MORE INFORMATION”. If they decided YES they held up a green card; if they decided NO they held up a red card and if they decided that they needed more information in order to reach a decision, they held up a yellow card. After the final stage audience members could no longer request more information and they had to make a YES/NO decision. Inherently the game was designed so that the decision was sensitive to multiple considerations and any sense of a “right” course of action was unclear.

The Results

A “Swingometer” was used to track the decisions of the audience on each occasion that the game was played. As a tool gratefully borrowed from the coverage of the UK elections, the Swingometer showed the swing of the audiences decision. If more people voted NO, the arrow would swing into the red and if more people voted YES, the arrow would swing into the green. The images below show how the audiences voted over the three games. The concentric lines track the percentage of people who actually made a decision (YES or NO). The final position of the arrow shows the final vote in which everyone was forced to vote either way.

Game 1                                                        Game 2                                                         Game 3

Analysis

As a scientist I couldn’t resist the opportunity to plot the results. The graph on the left shows the swing of the result (y-axis) at each decision step (x-axis) over the duration of each game. The graph on the right shows the percentage of people making a decision (y-axis) at each decision step (x-axis).

So what do the results reveal? The audience members in game 1 voted consistently to oppose the adaptation scheme. In games 2 and 3 initial support for the scheme, based on limited information, waned over the duration of the game. Interestingly, despite large variability between the results from the three games in the early decision stages, the final decisions were very close; the audience in games 1 and 3 voted marginally to oppose the scheme whilst the audience in game 2 was split 50/50. Presumably this was partly the inevitable result of choosing a decision problem where the information was fractured and uncertain; yet I struggle to think of any climate change adaptation decisions where this is not the case.

One might have assumed that the percentage of people making a decision should have increased over the duration of the games. Broadly, this is what was observed. However in Game 1, after the third decision step the percentage of people who made a decision (YES/NO) decreased dramatically (shown by the black line in the right graph). Maybe people were confused by the concept of the game but on the other hand maybe the result reflects the fact that sometimes more information can lead to more confusion about the right course of action to take; the phrase “ignorance is bliss” comes to mind. Curiously the people who did vote after stage 3, continued to vote unanimously NO.

As I observed the voting patterns of individuals, I noticed that some audience members had made up their mind after just one piece of information. Either due to preconceptions about the proposed adaptation scheme, a genuine belief that the information continued to support their position, or plain stubbornness, these individuals ardently continued to vote the same way throughout the six decision stages. Other individuals appeared to be more fickle and their votes seemed to change according to the latest piece of information. One of the aspects I found particularly interesting was how people voted after a particularly key (at lest in my view) piece of information. Observed rainfall for the region over a period of thirty years revealed a slowly decreasing linear trend but was masked by large inter-annual and apparent decadal variability. I had envisaged that the high level of observed variability would lead most to abandon the need for a climate change adaptation measure specifically recommended to reduce the risk of droughts. However this piece of information seemed to polarise the audiences. I can only speculate that people with different areas of expertise interpreted this piece of evidence differently. Of course throughout the game people may well have been confused about exactly what was going on so there is undoubtedly some noise in the results. Nevertheless I imagine that this feature is common to any decision making activity involving a group of people with different areas of expertise.

I certainly felt that running the game with delegates at COP 17 was a useful exercise to demonstrate the nuanced nature of decision making under uncertainty. Furthermore it illustrates the challenges in communicating climate information to people with different levels of scientific understanding and interest. In writing this blog I realise that there is much more I can say regarding the analysis but at the risk of boring the reader I omit some of my interpretation. Nonetheless this shows how much insight one can gain from a seemingly simple “game”. I do hope those who played the game enjoyed it!

What will they remember?

Personal observations from the final hours.

We sent 6 people from CSAG, and UCT had a handful more there.  We engaged, we had one of the best stands, we benefited personally from new contacts and collaborations, we worked hard and we also had fun.  But …

I had hoped to close my posts on COP 17 with something in a positive vein.  Days of crowds and noise, endless discussions and meetings, promotions, explanations, photographing people, blunt interviews, demonstrations, Fossil of the day awards, giving talks everywhere, sitting on panels, running, heat and humidity, meals both good and bad, money on blatant display, rampant egos and selfless advocacy, good conversations and thanks for those who traveled with me, and a progressive exasperation at the obstreperous behavior of the world’s leading political and economic powers.  How to make sense of all this, of all the nuance, bravado, desperation, strategic maneuvering, brinkmanship, all permeated with selfishness.

So many adjectives, so many ways to describe a dirty picture.  Perhaps its a fitting metaphor that oil and coal leave one stained and streaked with filth.

There have been successes; small enough that one has to search for them.  With the current negotiation extension (till Sunday if the latest tweeting is to be believed), there remains a small window of time in which something of real value can be achieved.  If that happens I will gladly come and re-edit this post.  But I suspect there will be no need.

Tweets that I see right now carry a note of desperation: “You can make COP17 a success!“, “Now is time to lead on a legally binding UNFCCC treaty by 2015!“, “Oxfam: Coalition of ambition must revitalize sputtering Durban climate talks“, “… it hasn’t been this bad for the last five years“.  Tweets that will live on in the ether till anthropologists one day mine them and ask, “What were they thinking?“.

Total collapse is not on the cards.  I suspect those in the negotiations will point to the sparks of possibility at COP 18.  Those of an optimistic frame of mind will find hope.  Those of a pessimistic nature will descend into depressive theories of conspiracy.  The bulk of the world, the majority who do not understand, will think about holidays, Christmas, and other more present personal challenges and stresses.

So what do I make of it?  I’ve been angry in the past two weeks more frequently than is comfortable.  I’ve laughed a lot more than most days.  I’ve watched and talked, and come to the conclusion “so what else did you really expect?”.   What we’ve observed is no more than base human nature exposed; serving self interest first, desensitized to the troubles of others, living the “now” at the expense of the “then”.

At the end of the day, when all is said and done, is this any different to the stratagems between the rich and the poor that starkly characterizes my home city?  How is any of this unique compared to exploitation throughout history?

What then?

I wrote the following in one of the first blog posts: ” Thus, the challenge of COP-17 is inherently ethical.  COP-17 is a power struggle, one where altruism often takes a back seat while each nations seeks to assert their own agenda.  Meanwhile, the paradoxical combination of globalization and polarization continues, all the time increasing the risk exposure of the vulnerable.”

In the face of this we continue as before; on the back of past choice we now choose again, and reap the consequences as we have always done.

Polar trekking in 2065