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Critical Climate Change Update

Jonathan's notes from the lecture:

Throughout this year Victoria University have been holding a series of [[http://www.victoria.ac.nz/climate-change/events/NZCCRI%20Seminar%20Series.aspx|seminars on Climate Change]]. Last night they presented a homegrown world leader on the subject - Dr David Wratt from NIWA.

Dr Wratt is also a lead scientist for IPCC, so I was particularly interested to hear his presentation, as IPCC have been heavily criticised lately for being too conservative in their 2007 scenarios.

Here is his presentation in a nutshell:

  1. Global warming since 1900 is absolutely certain. Sea level is rising and snow and ice cover is decreasing.
  2. Greenhouse gases have increased from human activity.
  3. In 2007, the International Panel on Climate Change (IPCC) stated that there is a 90% probability that human activity is causing the warming.
  4. Since 2007, new science has confirmed that:
    • Temperatures have been at the upper end of IPCC projections
    • global emissions have been at the upper end of IPCC projections
    • Antarctica is also warming
    • melting of ice sheets is more likely
    • ocean acidification from CO2 is more likely
    • the emission released now, will cause changes that are irreversible

So where did IPCC go wrong?

Well, it’s not that they were wrong, but just that they really were too conservative.

Lets take sea level for example. Their 2007 projection was for only 18-59cm of sea level rise, BUT that was excluding any ice sheet melting. Now, only two years later, Dr Wratt says 80-100cm is likely, and that some papers are suggesting up to 2 metres.

Furthermore, he believes we are currently on track to get 2-4 degrees temperature rise this century, which will lead to 7 metres sea level rise.

He went on to list all the other major effects of climate change if emissions are not drastically reduced. It was a looooooonnng list of dangerous climatic changes, which, in a typically unemotive scientific egghead way he summarised by saying:

“These findings strengthen the reasons for concern.”

It was like listening to HAL, the computer in 2001 A Space Odyssey.

Thousands of species will become extinct, and people will die in the millions from starvation, drought, floods, etc…. “These findings strengthen the reasons for concern.”

Then he moved on to the targets that are being currently discussed by politicians, which reminded me of Kashi Leuchs and his 350 campaigning (see www.350.org/riders).

It was Dr Wratt’s view that atmospheric concentrations of 350-400 parts per million (that’s where we are now), will inevitably result in 2.0-2.4 degrees warming, and 0.4-1.4m sea level rise, by the year 2100. That would spell DISASTER. for most developing countries – indeed it will wipe some of our pacific neighbours off the map if we let it happen.

Unfortunately, because CO2 has such a long life, to avoid this disastrous scenario there would have to be emissions reductions in the range of 50-85% by 2050, followed by a downward trajectory to zero emissions.

Is this possible, I wondered? The current National Government has an ETS bill before parliament that only aims for 50% reductions by 2050, and does virtually nothing in the next 5 years to actually reach that target. In other words, they’ll do as little as possible, for as long as possible, so as not to harm the economy.

At this point someone from the audience jumped in and stated the obvious: “WE NEED TO START REDUCING NOW OR WE WON’T MEET OUR TARGETS”.

Dr Wratt, calmly agreed.

Someone else asked “WHAT ABOUT POPULATION?”

Dr Wratt, calmly pointed out that the targets were regardless of population and as the population grows emissions reductions becomes more challenging.

Someone else said “WHAT ABOUT TIPPING POINTS, SUCH AS METHANE FROM MELTING PERMAFROST!”

Dr Wratt calmly replied that such tipping points currently involved too many scientific uncertainties, so IPCC had not factored them into their scenarios.

I left the seminar firmly believing that we are currently committing the biggest humanitarian crime in history. Food, land, life and hope, is being robbed from future generations on a scale that no despot of the past ever achieved.

Action is needed on two levels – political and personal.

Our politicians will not aim for safe reductions in emissions unless we/you ask them to accept the best science available and aim for less than 2 degrees, or as Kashi Leuchs puts it, 350 ppm (check out http://www.350.org/riders), or as Lucy Lawless puts it 40% by 2020 (check out http://www.signon.org.nz/).

On a personal level, how can we become informed and have enough vision to see and feel the impacts that will affect those people and places we love? And, more critically (because the environment doesn't respond to what we feel, or think), how can we take action to reduce our personal emissions, starting now?

Jonathan Kennett, 10 Oct 2009


Page last modified on 12 October 2009 at 09:10 PM