A tale of two hemispheres

Jim RenwickAt the end of June, Professor Jim Renwick of Victoria University gave his inaugural lecture. As you might expect of a climate scientist, it concerns what we know about the climate system and where we’re heading. He pulls no punches. Jim has been kind enough to put together a text version of the lecture for Hot Topic: it follows. You can watch the full lecture, with accompanying slides, on the video embedded at the end of the post.

We live in a golden age of earth observation. With a few clicks of a mouse on a web browser, any of us can see the state of the global ocean surface, the current condition of the Greenland ice sheet, how much rain is falling in the tropics today, and on and on. Plus, the International Space Station (ISS), and a series of satellites such as MODIS give us wonderful images of our home planet. The climate science community can tell, with unprecedented coverage and timeliness, just what is going on in the climate system. It is a great time to be a climate researcher, but also a worrying time, in both cases because we can see exactly what is changing.

One thing the ISS pictures emphasise is just how thin the atmosphere is, a thin blue layer between the solid earth and the blackness of space. Not only is this life-supporting envelope very thin, some of the key gases in the atmosphere are there in only trace amounts, so we can change the properties of the atmosphere easily, by targeting the right gases. The discovery of the ozone hole 30 years ago brought this home with a bang. And we’ve found that build-up of carbon dioxide (CO2) in the atmosphere can have a profound effect on the climate system, right down to the bottom of the oceans.

Carbon dioxide is important because it’s a crucial control on the surface temperature of the earth. It is very good at absorbing heat (infrared radiation) welling up from the earth, then re-radiating both up and down, in the process warming the earth’s surface. The effect is very like a blanket put on a bed – what’s under the blanket warms up. More CO2 is like putting another blanket on the bed and less is like taking away a blanket. No CO2 and the earth freezes – temperatures like we had in the South Island in late June would be the norm everywhere, all the time. While there are several other “greenhouse gases”, carbon dioxide is the most important since it stays in the atmosphere so long, hundreds to thousands of years.
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TDB Today: Dragon breath and the age of consequences

In my column at The Daily Blog this week — Dragon breath and the Age Of Consequences — I take a look at the latest news on Arctic methane. It’s not good, as Jason Box demonstrated by not mincing his words about the seriousness of the threat. For an idea of the consequences, I strongly recommend finding half an hour to look at the video above. Max Wilbert interviews some of the top scientists in the field (including East Siberian Shelf methane expert Natalia Shakova), and the result is a good overview of the pace of change up North and the sheer scale of the permafrost carbon threat.

Thin Ice: what polar science is telling us about climate

This guest post is by professor Peter Barrett, executive producer, and Suze Keith, marketing advisor for Thin Ice.

Scientists can tell human stories about climate change, and a group of us have been working on just that for the last few years. We’ve produced a film — Thin Ice – the inside story of climate change — which follows a scientist, geologist and camera buff Simon Lamb, who is concerned at the flak his climate science colleagues have been taking.

Simon travels from the Antarctic to the Arctic. He listens to scientists talk about their work, hopes and fears, and discovers how the astonishing range of research really does fit together. By the end there are just two messages – that our ultimate goal should be zero carbon emissions (in line with the latest IPCC report), and that science really does work. As paleoclimatologist Dave Harwood says to young people at the end of the film:

Don’t be scared by this thing. Come and join in our effort. Be the best scientists and engineers you can, and we’ll deal with it.

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The dishonesty of de Lange and Carter: zombie lies under Greenland ice

According to Waikato University’s Willem de Lange and freelance climate denier Bob Carter, the whole Arctic is cooling strongly. When Bill and Bob plagiarised their own work for the Heartland-funded and published Non-governmental International Panel on Climate Change (NIPCC) second report, they were not just copying their own words, but also plagiarising earlier efforts by the NIPCC and Craig Idso’s Centre for the Study of CO2 and Global Change. In fact, a 2007 misrepresentation by Idso of a 2004 paper about temperatures up to the 1990s in a single Greenland fjord has been handed down through seven years, successive “authors” and NIPCC reports until it has become an unbelievable lie that de Lange and Carter are happy to repeat for a new audience.

When I was doing the research for my article on de Lange and Carter’s sea level rise report for Nigel Lawson’s Global Warming Policy Foundation, I was forced to dig around inside the chapter they had written for most recent NIPCC report — the second of its ilk (NIPCC2, Chapter 6). What jumped out at me was this paragraph, from the conclusions to section on page 792:

Regarding the Northern Hemisphere, the Arctic regions have been cooling for the past half-century, and at a very significant rate, making it unlikely Greenland’s frozen water will be released to the world’s oceans anytime soon. This temperature trend is just the opposite — and strikingly so — of that claimed for the Northern Hemisphere and the world by the IPCC. Accompanying the cooling, the annual number of snowfall days over parts of Greenland has also increased strongly, so an enhanced accumulation of snow there may be compensating for the extra runoff coming from mountain glaciers that have been receding.

That’s right. Carter and de Lange are happy to put their names to a statement that the Arctic has been cooling for the last 50 years. Everybody else thinks that the Arctic has been warming strongly for the last 30 years, as this graph of Arctic surface air temperatures shows:


Source: NOAA’s annual Arctic Report Card, 2013 update.

So how on earth do they justify a claim that the Arctic has been cooling “at a very significant rate”? The answer’s simple. They don’t. There is no supporting reference given for that statement. It is offered as a conclusion without a hint of a reason supplied in the text above it, or in the references below it. But Bill and Bob didn’t just make it up, they stayed true to form and copied it word for word from somewhere else.

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TDB Today: WACCy weather and a warm year


A classic case of WACCy weather in the northern hemisphere, seen here in a map from the excellent Climate Reanalyzer site, prompts me to discuss the 2013 global temperature numbers, the El Niño-Southern Oscillation, and what sea ice loss is doing to northern hemisphere weather patterns in my post at The Daily Blog this week. We live in interesting times…