The climate scare rests on predictions produced by mathematical modeling. Freeman Dyson, one of the world’s finest scientific minds, says prediction isn’t what those models do – and that the climate conversation is ignoring important facts.

In an era of Facebook and Twitter, we are as likely to hear about events from acquaintances, relatives, and colleagues as from the news media directly. That’s what happened yesterday. Soon after a 20-minute video interview with legendary physicist Freeman Dyson was posted on the Vancouver Sun website, I saw a reference to it in my Facebook feed. Then fellow Canadian blogger Hilary Ostrov tweeted about it and a post went up at the UK Bishop Hill blog. American blogger Tom Nelson posted transcriptions of many of Dyson’s remarks, and the video got mentioned over at  WattsUpWithThat. Word-of-mouth is amazing and powerful in the digital age.

The video in question is a project of Oh Boy Productions. It’s part of a series of “Conversations that Matter” that are being aired on British Columbia television stations as well as hosted on the Vancouver newspaper’s website.

In this video, broadcaster Stuart McNish does what journalists are supposed to do: help the public make informed decisions by covering a range of intelligent viewpoints on current affairs.

The 91-year-old Dyson is an eminent scientist who also happens to be a gifted writer. The opposite of a showboat, his manner is quiet, calm, and careful. The take-away message from this video is that much of what routinely gets said about climate change is irrelevant.

The main issue is not: Is human-caused climate change occurring? Repeatedly, Dyson tells us that “the fact that it exists is not a question.” To ferociously insist – as politicians and activists do – that man-made climate change is real is meaningless. That remark is worthy of a child. It demonstrates no sophistication whatsoever.

The crucial questions are, instead:

1. Is humanity’s effect on the climate large or small?
2. Big-picture, is it harmful or helpful?

At the 21:30 mark, Dyson explains:

Man-made climate change certainly is real. There’s no doubt it’s real. The question is: how much and whether it’s good or bad? Those are quite separate questions. I would say it’s, on the whole, good. Also, it’s not as large an effect as most people imagine.

Activists insist that human-produced CO2 emitted into the atmosphere will trigger climate chaos. They believe this because a sub-group of scientists known as climate modellers say so.

But Dyson, who has watched that field for four decades, disagrees. While mathematical models help researchers understand certain aspects of the climate, he says, models are useless for predicting what’s going to happen more than five days from now.

In other words, the entire climate scare rests on a belief in the ability of climate models to foretell disaster decades or centuries hence. But one of the world’s finest scientific minds says that long-term prediction is not what those models do. At all.

We’re focusing our attention, says Dyson, on entirely the wrong thing. As the level of CO2 in the atmosphere has gradually climbed (from 280 parts per million in 1850 to 400 parts per million today), the world has grown greener. This is because, as we all learned in introductory biology, CO2 is plant food. In Dyson’s words:

There are huge, non-climate effects of carbon dioxide which are overwhelmingly favourable which are not taken into account. To me, that’s the main issue, that the Earth is actually growing greener. This has actually been measured from satellites. The whole Earth is growing greener as a result of carbon dioxide in the atmosphere, so it’s increasing agricultural yields, it’s increasing the forests, it’s increasing all kinds of growth in the biological world. [3:50 mark on the video]

A bit later, Dyson calls the CO2 increase

extremely important. It’s enormously beneficial both to food production and to biodiversity, preservation of species, and everything else that’s good.

You’d think environmentalists would be dancing in the streets. You’d think they’d be celebrating CO2 as a miracle cure. A bit more of it in the atmosphere has averted famine and made the natural world stronger and healthier.

But many environmentalists regard human beings as defilers. For example, in The End of Nature, anti-global-warming campaigner Bill McKibben romanticizes “nature free from the hand of man” and longs for a lost Eden (pp. 42, 78).

But to return to the grown-up conversation:

Q: Is humanity’s effect on the climate large or small?
A: Overall, it appears to be small.

Q: Big-picture, is it harmful or helpful?
A: The CO2 we’ve emitted so far has increased food production, augmented our forests, and enhanced biodiversity.

These are the decisive questions.

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see also:

• Fixed: the IPCC’s Climate Model Evaluation Game
• Climate Confusion
• here’s a direct link to the video

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