Climate change models omit key component

Climate models used to study temperature change from greenhouse gases are missing a key ingredient — economics, according to a new study by a University of Guelph professor.

Economist Ross McKitrick, an expert in environmental policy analysis, says most models ignore the effects of socioeconomic change on land use changes, making those models inaccurate.

The study, co-authored with Lise Tole of Strathclyde University, was published online in the journal Climate Dynamics.

McKitrick has studied how land use changes from urbanization, agriculture and other surface modifications affect temperature trends around the world. Past research suggests these effects might account for some of the warming patterns in weather data. Climate modelers assume that the effects are filtered out at the data processing stage, he said.

“As a result, when researchers look for explanations of regional patterns of climatic changes, they rule out things like urbanization by assumption and give greater weight to global factors like greenhouse gases and solar variations,” McKitrick said.

The study examined data from 22 sophisticated climate models used by the Intergovernmental Panel on Climate Change (IPCC). The researchers compared how accurately those models would have predicted spatial warming patterns over land between 1979 and 2002 with predictions from a much simpler model using data on regional industrialization and socioeconomic growth.

“The contrasts were striking,” McKitrick said. Twenty of the IPCC models made predictions that were no better than random guesses or that contradicted the observed patterns, he said.

“Only two of the 22 models showed any explanatory power for the temperature changes over the same period.”

By contrast, the simple economic model made much more accurate predictions.

Using various statistical techniques to compare modeling approaches, the researchers found that usually the economic model was essential and the climate model could be dropped, but never the other way around.

One technique involved searching more than 537 million combinations of climate model outputs and socioeconomic data for the best possible mix. The research team found that combining three of the 22 climate models and a small number of socioeconomic indicators best explained the spatial pattern of surface temperature trends.

“By assuming the socioeconomic effects are not there, a lot of climate researchers are ignoring a key feature of the data,” McKitrick said.

The researchers also found that the best climate models aren’t necessarily the most well-known ones. The best models came from labs in China and Russia and from one American institute; models from Canada, Japan, Europe and most U.S. research labs lacked explanatory power, either alone or in combination.

The study has important implications for policy-makers, McKitrick said. “Computer forecasts of regional climate changes between now and 2030 can look impressive in their detail, but it would be wise not to make major policy decisions without first looking into the model’s forecast accuracy.”

The findings are also important for researchers, especially those using climate data sets. “A lot of the current thinking about the causes of climate change relies on the assumption that the effects of land surface modification due to economic growth patterns have been filtered out of temperature data sets. But this assumption is not true.”

 

Originally published on June 20, 2012 by the University of Guelph. Ross McKitrick speaks at the What Matters Now event in Thunder Bay on March 4.

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If you’re happy ...

Cathy Majtenyi | October 22, 2014

Brock University recently launched a series of monthly podcasts covering a wide range of themes. As part of our own package of “Belief” related blog posts, Research Matters is pleased to present this exclusive interview with Brock Associate Professor of Psychology, Michael Busseri. Busseri will join two other colleagues to explore this topic in Brock’s January 2015 podcast, “What gives us a sense of wellbeing?” (Busseri is no stranger to Research Matters, having answered one of the great questions asked of the Curiosity Shop, “Why is the grass always greener on the other side?”)   BU: How do you define wellbeing? MB: Historically there have been two broad traditions. One looks at things like satisfaction, enjoyment, pleasure and not pain. That’s called the Hedonic Tradition. The second tradition is about finding meaning, purpose and growth; that’s called the Eudemonic Tradition. Where the rubber meets the road for most people is the question of, ‘How can I get more of that, whatever it is?’ It all sounds good: who wouldn’t want a meaningful life, a purposeful life, an enjoyable life? One camp says, you know what? Happiness, wellbeing – regardless of the type – is determined by the genetic lottery of life. It’s more like a personality trait. They may fluctuate around that day-to-day, moment-to-moment, but if you check in with them every year and do that for 10 or 20 years in a row you find a lot of stability. The other camp says, well, that might be true for many people but there’s still a significant chunk of individuals who experience radical changes as a result of, unfortunately, largely negative life events: the death of a spouse; the loss of a job; a tragic injury; horrible crime. The impact of that event can last years for some individuals. BU: Can we become happier? MB: Short-term: there’s lots of evidence that people change their wellbeing; moment-to-moment, day-to-day, week-to-week. Longer term: it’s harder to find people who show the golden pattern of continuous increases. Where there are long-term changes in wellbeing, it tends to be on the down side. The ratio is almost two to one. But even those people who experience the lasting decreases – they are rare. We can be talking no more than 10 per cent of the population. The vast majority of us over the long term tend to be stable.   BU: Should we be discouraged or encouraged by those statistics? MB: The argument is, this is actually a positive thing! It shows how adaptive and resilient people are. The high highs, the people who experience lots of positive experiences in our lives are also the individuals who tend to experience lots of lows. In the extreme, we tend to think of these as “manic” individuals. Usually, this idea of huge fluctuations in wellbeing is not something we would recommend. BU: Is there any part of our wellbeing we can control? MB: Most of us want a satisfying and meaningful life beyond simply saying, well, you may win or lose the genetic lottery of life. But we can choose how we spend our time. Moment-to-moment, day-to-day, week-to-week, we can have some influence by choosing certain activities or choosing to spend time with people who are meaningful and important to us. Even if we realize that that boost is going to be temporary, who cares? For those moments that we’re experiencing it, we’re happy! BU: Can we “bank” these happy moments to draw upon when we feel sad? MB: Another controversial issue. Some people have argued that what you experience moment-to-moment gets stored in a separate bank than the part of you that holds the beliefs about your life. Daniel Kahneman, a Nobel prize-winning psychologist, has suggested we talk about this as two “selves.” The “experiencing self” is the you that, moment-to-moment, is experiencing life. The other self is the “story-telling self,” which has beliefs about how your life is going. Often those beliefs don’t align very closely with your experiencing self. It turns out there are cultural myths about wellbeing that influence our stories. One of these is that young adults tend to believe life gets better and better, and older adults tend to believe that life gets worse and worse. Both are myths, but you find these myths around the world. They’re wrong because for most individuals, the “real life story” is one of stability, not one of inclines and declines.

Lucid dreaming depends on ...

Trent University Staff | October 21, 2014

New research by Trent University Oshawa Anthropology professor Roger Lohmann and graduate student Shayne Dahl indicates that cultural learning shapes the kind of awareness and control people can experience while dreaming. “Scouring the ethnographic record on dreaming for hints of lucidity under Professor Lohmann’s guidance, I found something surprising: that lucid dreaming is widely thought to have serious consequences,” said Dahl, who completed his M.A. thesis, “Knowing Means Connecting with the Source of Life: Knowledge and Ethics among Blackfoot Traditionalists” at Trent in 2012. (He is now a Ph.D. candidate at the University of Toronto.) “As one of my Blackfoot informants put it, ‘You could die in your dream.’” Lohmann and Dahl’s findings were published in the 2014 collection, Lucid Dreaming: New Perspectives on Consciousness in Sleep. Lucid dreaming – waking consciousness arising during a dream – has been a hot topic of scientific research in recent years. According to Lohmann and Dahl, the common assumption that dreams are products of isolated imaginations has distorted our understanding of lucidity’s variation in form, function, and real-world outcomes. Pop culture portrayals in films such as Avatar and Inception present fantasies where lucid dreaming enables marvelous real-world powers. Many traditional and religious cultural worldviews take the relationship between waking and dream worlds as reality rather than fantasy. Lohmann’s fieldwork in Papua New Guinea among the Asabano people explored how they used dreaming as evidence for and contact with supernatural beings. “Asabano converts often told me that seeing dreams of Jesus or Heaven convinced them that what the missionary told them was true,” said Lohmann. “It struck me that they had to believe their dreams were more than figments of their own imaginations to reach that conclusion, and that I, for example, would not be convinced by the same experience because of my different cultural background.” Similarly, Dahl’s fieldwork in Alberta included encounters with Aboriginal medicine men who practiced lucid dreaming. “Shayne’s field experiences and his search of ethnographic literature brought home to us that lucid dreaming has profound potential for people who think it’s more than just a fantasy. We found that descriptions of lucid dreams are radically different in form, function, and outcome depending on the cultural assumptions of the dreamer,” said Lohmann. Their research revealed evidence that in some cultures, lucid dreaming is unknown, while in others it is a commonly taught skill. In some, lucidity is tacit rather than acknowledged, but people nevertheless believe that they actively undertake goals in their dreams. Lohmann and Dahl found that this implicitly lucid “volitional dreaming” commonly appears in ethnographic accounts of dreaming. In cultures where “generative” theory holds sway, dreaming of something is understood to cause it to happen in the waking world. This leads people to experience lucid dreams as opportunities to create or do magic. By contrast, people who believe dreams are what one sees during “soul travel” use lucid dreams as an opportunity to spiritually visit real places. “Even when we consciously disbelieve our dreams,” Dahl said, “They still affect us at a deeper, emotional level that we can’t easily control with reason.” “All of this shows that cultural dream theories are multiple, that people invoke them in complex ways, and that they are at the very core of what lucid dreaming is and what it makes possible,” said Lohmann. This story was originally published by Trent University on, July 15, 2014. Is has been edited for style, brevity and clarity and appears here with permission.

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U of T Staff (With introduction by Patchen Barss) | October 20, 2014

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