Seeing children, activists, and ordinary people in 181 countries come together around 350.org's worldwide at 5,200 day of action events last week was truly inspirational. Their goal of putting the focus on science and citizens and not special corporate interests and backroom deals is admirable. They hoped to influence the United Nations Framework Convention on Climate Change (UNFCCC) negotiations in Copenhagen, Denmark in December to lower greenhouse gas emissions.
But their message could be dangerous, since in his paper, "Target Atmospheric CO2: Where Should Society Aim," NASA Climate scientist Jim Hansen said recently, "The evidence indicates...that the safe upper limit for atmospheric CO2 is no more than 350ppm."
If burning fossil fuels like coal and oil during industrialization has created the mess we're in with climate change, it seems only logical that we should aim for pre-industrial levels of atmospheric CO2 of 280 ppm. We should be aiming for a number that is sure to reverse climate change, especially now that feedback effects like methane, a greenhouse gas 25 times more powerful than CO2, is bubbling out of melting permafrost in the arctic and could rapidly accelerate climate change. If we're organizing around a goal that is too little, too late, with the survival of humanity hanging in the balance, we're not just wasting time, we're toying with our own annihilation.
We've come a long way from President Bush's plan to lower average U.S. temperatures by switching from Fahrenheit to Celsius. However we are currently at 390 ppm CO2 and rising 2 ppm annually. Rising CO2 and other greenhouse gas levels are directly linked to increasing average global temperatures, which are now expected to rise as high as 7.2 degrees Fahrenheit, the very worst case scenario just a few years ago.
Carbon dioxide levels have risen higher in the past 100 years than at any other time in the past 800,000 years. Carbon dioxide has a half life of up to 800 years. That means that even if we dramatically cut CO2 emissions tomorrow, what's already in the atmosphere, will take a LONG time to disappear.
On their website, 350.org says, "We need an international agreement to reduce carbon emissions fast." Climate Scientist, Dr. Brenda Ekwurzel with the Union for Concerned Scientists said, "Unfortunately, a reduction in CO2 emissions still leads to growth in CO2 in the atmosphere. Only the complete elimination of CO2 emissions would lead to a slow reduction in CO2 in the atmosphere over the next century." So if we assume that 350.org is aiming to cut emissions and not atmospheric greenhouse gases, they are way off the mark.
We're already dramatically overshooting the upper limit and it's not clear how long we can do so. Hansen says, "If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects." He said, "We have passed tipping points, but we have not passed a point of no return. We can still roll things back, but it is going to require a quick turn in direction."
In his brutally honest, but hopeful commencement speech at the University of Portland, Paul Hawkins said, "Hey, Class of 2009: you are going to have to figure out what it means to be a human being on earth at a time when every living system is declining, and the rate of decline is accelerating. Kind of a mind-boggling situation," he said..."but not one peer-reviewed paper published in the last thirty years can refute that statement..."
"Forget that this task of planet-saving is not possible in the time required. Don't be put off by people who know what is not possible," said Hawkins. So if you think aiming for 280 ppm atmospheric CO2 is impossible, as Hawkins says, "Do what needs to be done, and check to see if it was impossible only after you are done."