Wonderful.
Thank you very much for inviting me to provide some testimony here. What I would like to do is provide a bit of background with respect to a declaration that was put forward by scientists to Bali at the meeting that was held between December 3 and 14, 2007. This is a 2007 Bali climate declaration by scientists. I'll read it to you. It says:
The 2007 IPCC report, compiled by several hundred climate scientists, has unequivocally concluded that our climate is warming rapidly, and that we are now at least 90% certain that this is mostly due to human activities. The amount of carbon dioxide in our atmosphere now far exceeds the natural range of the past 650,000 years, and it is rising very quickly due to human activity. If this trend is not halted soon, many millions of people will be at risk from extreme events such as heat waves, drought, floods and storms, our coasts and cities will be threatened by rising sea levels, and many ecosystems, plants and animal species will be in serious danger of extinction.
The next round of focused negotiations for a new global climate treaty--within the 1992 UNFCCC process--needs to begin in December 2007 and be completed by 2009. The prime goal of this new regime must be to limit global warming to no more than 2ºC above the pre-industrial temperature, a limit that has already been formally adopted by the European Union and a number of other countries.
Based on current scientific understanding, this requires that global greenhouse gas emissions need to be reduced by at least 50% below their 1990 levels by the year 2050. In the long run, greenhouse gas concentrations need to be stabilized at a level well below 450 parts per million, measured in CO2-equivalent concentration. In order to stay below 2ºC, global emissions must peak and decline in the next 10 to 15 years, so there is no time to lose.
As scientists, we urge the negotiators to reach an agreement that takes these targets as a minimum requirement for a fair and effective global climate agreement.
In my years as a climate scientist, since the 1980s, I have never before witnessed such a spontaneous coming together of scientists around the world. This declaration was put forward by a number of scientists at the University of New South Wales in Australia and was signed by between 200 and 250 of the world's top climate scientists. This is not something that was driven politically. It was not something that was driven by special interest groups. It was driven by the scientific community to try to feed into the Bali process--a process that seems to be ignoring what the scientific community is telling the world's leaders, including those leaders in Canada.
I'm speaking to you as the lead author of the IPCC's second, third, and fourth assessments, back in 1995, 2001, and more lately 2007. I'm also the chief editor of the Journal of Climate, which is the premier journal for publishing new scientific research in all aspects of climate science.
When we talk about Bill C-377, one of the key things you'll ask is whether 80% is the right number or whether 70% is the right number. I'm not going to speak to a particular number. What I can say is that any stabilization of greenhouse gases at any level requires global emissions to go to zero. There is no other option. To stabilize the level of greenhouse gases in the atmosphere at any concentration that is relevant to human existence on the planet, we must go to zero emissions. The reason is that the only natural mechanisms for the draw-down of carbon dioxide on longer time scales occur through weathering of rocks, which happens on hundreds of thousands of year time scales, and the dissolution of carbon carbonates from the sediment of the ocean, which happens on tens of thousands of year time scales.
Things like the terrestrial biosphere saturate out this century and can no longer take up any more carbon dioxide. The ocean, as it warms, also begins to lose its effectiveness at taking out carbon dioxide.
So in order to stabilize, we must have global emissions go to zero. That's a big task, and it requires leadership. I'm hoping, as a Canadian, that we in Canada can show such leadership.
Another way of looking at this is that there has been a lot of focus in terms of emissions and a lot of focus in terms of stabilizing at a level of greenhouse gases. The climate system doesn't care about the emissions today or yesterday; what it cares about is accumulative emissions of carbon dioxide since pre-industrial times. We've put out about 458 billion tonnes of carbon to the atmosphere since that time, and it turns out if you want to not break the two-degree threshold with a 66% probability, we only have another 484 billion tonnes we can put out, and that's from now until eternity. We're putting it out at more than 10 billion tonnes a year, so you can see the challenge is large.
I'll end there and urge you to take this bill seriously and move toward implementing policies in Canada that will show leadership internationally.