Can we have early warning of climate ‘tipping points’?

  • 21 Jun 2011, 13:30
  • Verity

© Carsten Egevang/ARC-PIC.COM

Climate 'tipping points' are thresholds within the climate system, where small changes in some part of the climate can cause abrupt and perhaps irreversible environmental change.

The scientific concept of tipping points has certainly captured the popular imagination over the last few years - although not almost in the most scientifically accurate way - see the somewhat implausible film 'The Day After Tomorrow,' in which a sudden change in ocean currents leads to a new ice age.

It may be that the idea of tipping points have stuck in the imagination because the impacts of fast and unstoppable environmental change on society are potentially huge. This may also be why Sir John Beddington, Government Chief Scientific Advisor, recently met with the UK's leading climate experts to review the scientific evidence for tipping points, and to discuss their implications for policy.

Examples of potential tipping points are shown in the figure below, and include scenarios such as irreversible melting of the Greenland Ice Sheet, or Amazon rainforest dieback.

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IPCC SRREN report reveals legitimate issues with the organisation's communications

  • 17 Jun 2011, 18:00
  • Tim

Recent controversy over the IPCC's relationship with green NGO's has centred around a  press release the IPCC put out in early May, coinciding with the release of the Summary for Policymakers of its Report on Renewable Energy Sources and Climate Change Mitigation.

In it, the IPCC gave headline prominence to a single, optimistic scenario for renewable energy provision, based on a single study that was ultimately traced back to a Greenpeace report. That report's own lead author, Sven Teske - himself a member of Greenpeace International - was also one of the Lead Authors working on (a chapter of) the IPCC'sreport.

Critics have complained that the IPCC had allowed an author to review his own work, in a fundamental conflict of interest, and have suggested that Greenpeace has been allowed to "dictate" the report's headline conclusions. The story has now been picked up by, among others, the Independent, New Scientist, the New Zealand Herald, the Daily Mail and the New York Times.

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Sunspots, ice ages, and the biggest experiment ever

  • 17 Jun 2011, 11:36
  • Verity

New solar research presented at an American Astronomical Society meeting this week suggests that the next solar cycle might be delayed, or not even happen at all.

This has prompted the sceptic community to rather drastically claim that we're about to enter a new ice age, with James Delingpole proclaiming: "It's official: a new Ice Age is on its way" and Newsnight covering the story in slightly more measured tones.

Whilst there's little doubt that the sun is behaving unexpectedly, to assume that this heralds the dawn of a new ice age is quite a leap to make, and, incidentally, completely disregards current scientific understanding of the issue.

The story has probably arisen from this line of the press release:

"An immediate question is whether this slowdown presages a second Maunder Minimum, a 70-year period with virtually no sunspots during 1645-1715."

 The Maunder Minimum coincided with part of a period of cooling that lasted around 300 years and affected large parts of the globe, known as the 'Little Ice Age'. The prospect of a new Maunder Minimum has therefore prompted some to suggest that an ice age is imminent.

While there is no doubt that solar activity affects climate, it is thought that the effects are relatively small compared to things like the effect of greenhouse gases, although this is hotly contested by climate sceptics.


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Mail fuels fears over energy bills but where’s the research to back them up?

  • 15 Jun 2011, 12:00
  • Christian

Household energy bills are being inflated by subsidies for "green" renewable energy according to a slew of stories in the Daily Mail, followed up by the Telegraph and based on claims made by Dr Benny Peiser, the director of the Global Warming Policy Foundation.

Reduced household incomes coupled with rising energy bills - with all major energy companies increasing their bills, and the announcement from Scottish Power that its domestic energy bills will rise by £200 - has meant that rising fuel bills will be a major anxiety for millions of people.

The GWPF are blaming price rises on green policies. Since 2002 energy bills have risen sharply. For the most part these increases are due to wholesale gas price rises, which also feed through into electricity prices.

However, as renewable targets and energy efficiency policies have become more ambitious a rising fraction may be due to green policies. The question is, how much?

Dr Peiser says green taxes currently make up between 15 and 20 percent, or from £154 to £206 of an average household's combined gas and electricity bill.

Despite the significant space and editorial support given to this story, the Daily Mail fails to provide sources for these figures in its front-page article on June 9 or any of the subsequent comment articles that have followed.

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Is 1.5 degrees a scientifically realistic target?

  • 13 Jun 2011, 17:00
  • Christian

We are currently half way through an interim meeting of the UN's Framework Convention on Climate Change (UNFCCC), the body that is supposed to be negotiating a sensible global climate deal. And once again, the disconnect between scientific and political reality is startlingly apparent.

As the world struggles towards some sort of agreement, the discussion about what shape a deal should take - and even what it should be aiming for - continues. The Copenhagen Accord [pdf], which the UNFCCC agreed to 'take note of' at the end of 2009, recognized

"the scientific view that the increase in global temperature should be below 2 degrees Celsius".

But at the beginning of last week, the executive secretary of the UNFCCC, Christina Figueres, went on the record saying

"Two degrees is not enough - we should be thinking of 1.5C. If we are not headed to 1.5C we are in big, big trouble."

Small island states - aware that their survival is threatened by climate change - have made repeated calls in the negotiations for the world to commit to keeping temperatures to 1.5 degrees above pre-industrial level. But their call has largely fallen on deaf ears. 

This is perhaps unsurprising given that its taken 20 years to get the world to commit to two degrees as a target, even in principle. But it is worth pointing out how far away from the current scientific reality the 1.5 degree target is. 

Figueres' statement coincided with an IEA assessment that global emissions from the power sector are at an all-time high - as assessment which suggests that if current trends in emissions continue, a four degree rise by the end of this century looks likely.

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Global warming since 1995 “statistically significant”

  • 10 Jun 2011, 16:30
  • Verity

Professor Phil Jones

The claim that global warming has stopped - one of the most overused and deeply flawed climate skeptic arguments - can finally be laid to rest today, following the publication of new data analysis by one of the country's leading climatologists.

Phil Jones, from the Climate Research Unit at the University of East Anglia, agreed in a BBC interview last year that the warming trend between 1995 and 2009 was statistically insignificant - but "only just".

This caused quite a stir with the Mail on Sunday proclaiming that Jones had made a "climate change retreat". Skeptics appropriated his statement as part of an on-going campaign to undermine climate science.

However, the BBC reports today that Jones has added the temperature data for 2010 to the record since 1995, and has found that this givesa warming trend that is statistically significant.

Global temperature has warmed by around 0.19 ˚C between 1995 and 2010. This surely must be the end of the 'no more warming' claim.

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Food, hunger and climate change

  • 10 Jun 2011, 11:00
  • Neil

A slew of new reports have again highlighted the perilous state of the global food system. As the world struggles through the second global food crisis in three years, some argue this should be a wake up call to revitalize and stabilize global food production and trade.

The question now is whether climate change will make such crises more common. 

So far this year 44 million people have been pushed into extreme poverty by increased food costs, adding to the nearly one billion starving and 2.5 billion malnourished people around the world.

Global cereal prices increased 71 percent in the year to April 2011, more than three times higher than a decade ago. And the cost of meat hit an all-time high in May. Prices are set to continue rising, with Oxfam warning of a doubling in global food prices by 2030. 

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Impacts of a melting cryosphere – ice loss around the world

  • 09 Jun 2011, 12:00
  • Verity

© Carsten Egevang/ARC-PIC.COM

With delicately balanced ecosystems, weather patterns and a lot of ice, the planet's frozen areas (collectively known as the 'cryosphere') are some of the most sensitive to climate change. As the cryosphere warms, we can expect to see a range of knock-on effects. This briefing runs through what we know about how the cryosphere is reacting to climate change, and what the likely consequences of continued warming are.

The warming cryosphere

The cryosphere comprises of the Earth's ice - notably the Arctic, the Antarctic, and the world's glaciers.

Historical records suggest that Arctic sea ice began to decline around 1900, with a more accelerated ice loss since the 1950s. Since 1979, satellite records have confirmed an overall decline in summer sea ice coverage of around 13% per decade. Although fears that Arctic sea ice would reach a 'tipping point' and rapidly disappear currently seem to be unfounded, the mainstream view of scientists is that we will see ice-free summers in the Arctic ocean within the next few decades.

The major body of land ice in the Arctic - the Greenland ice sheet - has been found to be thickening inland. Nearer the coast, however, the ice sheet is thinning and shrinking, at an accelerating rate. Overall, the Greenland ice sheet has been found to be losing ice mass over the last twenty years, and this ice loss is becoming faster.

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Daily Mail reprints Lord Turnbull's scientific errors

  • 09 Jun 2011, 11:00
  • Tim

The Daily Mail's front page is top-lining on an attack on green energy today - with particular reference to a claim by Lord Turnbull of the Global Warming Policy Foundation that politicians "stop frightening us and our children".

On the inside pages the Mail huffs "We must stop pandering to climate scaremongers" and quotes from a recent report by Lord Turnbull extensively.

We took a look at the fifteen page report [PDF] for the GWPF, The Real Inconvenient Truth or "It Ain't Necessarily So"  a few weeks ago. We have reprinted our analysis below.

The briefing paper discusses the IPCC's assessment of climate science and the UK policy response. In the Foreword, Lord Lawson praises Turnbull's work as a 'dispassionate but devastating critique', and a 'measured verdict'.

But how reliable are its conclusions? Sadly, they are not reliable at all. Below are a few examples of where Turnbull gets things badly wrong, and one example of questionable quotation.

• The "Hockey Stick"

On the IPCC's assessment of historical temperatures, Turnbull writes that "[i]n its Third Assessment (2003), the IPCC compared its view to an ice hockey stick."

In fact, though the graph that has come to be known as the "hockey stick" - because of its largely flat shape, with an upward curve at one end - was included, a search of the IPCC website reveals that the words "hockey stick" feature nowhere in the Third Assessment Report. The Report was also published in 2001 - not, as Turnbull states, 2003.

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Latest emission figures show world on track for 4 degrees

  • 07 Jun 2011, 11:00
  • Robin

Figures released by the International Energy Agency (IEA) last week showed that carbon emissions from energy production reached a record high in 2010.

At 30.6 Gigatonnes, emissions were 5% higher than the previous record year in 2008.

Dr. Fatih Birol, the chief economist of IEA called the latest data "another wake-up call" while Lord Stern warned that "the room for manoeuvre is narrow and the window of opportunity is closing" for emissions cuts.

The IEA figures were particularly significant because emissions had been expected to fall as a result of the economic downturn. As a result of the recession, emissions fell in the UK and globally during 2009, leading some to suggest that the world had been given "breathing space" to start a shift to low-carbon infrastructure. The resurgence of carbon emissions makes it clear that this hasn't happened.

Australian blog Skeptical Science has now produced the following graph comparing current global emissions with the IPCC 'emissions scenarios', which speculate about future emissions and likely temperature changes that may result.

CO2_Emissions _IPCC_1024

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