NEW DELHI: The world must restrict its carbon emissions to 190 giga tonnes by 2050 if it is to have a chance of escaping the catastrophic consequences of global warming. These are the latest findings published in the scientific journal Nature. According to the findings, all earlier calculations have been set aside with the warning that the planet can withstand even less of the greenhouse gases than had been envisaged earlier. The warning has never been starker or simpler for everyone to understand. The latest studies show that there is a 75% chance that the world can escape the danger of global average temperature rising by more than 2 degrees Celsius over the pre-industrial era if it is able to keep its carbon emissions below 190 giga tonnes over the next 41 years.
Put simply, 190 giga tonnes is our carbon budget for the period up to 2050. But unlike a financial budget, there is no room for exceeding it. A 75% chance is, in scientific terms, reasonable, and nothing to be ecstatic about--but enough to give hope. If you think 190 giga tonnes is a huge amount of carbon to throw up in the air, read this--last year alone, the world emitted more than nine giga tonnes of carbon by burning fossil fuels.
The rate at which we emit carbon is increasing by 3% every year. If humanity continues to burn fossil fuels and gases unhindered at the same rate, the world will have consumed the entire carbon budget available to us-that is 190 giga tonnes-by 2029. Every single tonne of carbon after that will progressively reduce our chances of not letting temperatures increase above the 2 degree Celsius mark over the pre-industrialised era and consequently cause havoc.
For instance, if carbon emissions touch 310 giga tonnes between now and 2050, the chances of averting catastrophic climate change fall below 50%. The enormity of the task facing the planet becomes obvious after considering that if the world meets the most ambitious target that the major developed countries have talked about (and only talked about so far)-reducing global emissions by 80% from the 1990 levels by 2050-scientists estimate that 216-325 giga tonnes of carbon will have been sent up in the air, far exceeding the safe limit of 190 giga tonnes.
For those who may have forgotten the warning put out in 2007 by the community of scientists under the UN's intergovernmental panel on climate change, here it is again--if global average temperatures ever rise more than 2 degrees Celsius over the pre-industrial era, the world will see the irreversible and catastrophic impact of climate change that could impact billions of people, a large percentage of them being in India.
Two studies published in the latest edition of Nature warn world leaders that they are failing their people, and failing miserably. Both studies, conducted by different sets of scientists, use a common principle. Once we emit carbon in the air, it accumulates in the atmosphere. In other words, it sticks around for long. It does not break down. Stuck in the atmosphere, it warms up the planet.
Both warn that it's not just the emissions at present but the total accumulated emissions since the industrial era (when humanity started adding to the natural carbon in the air) that will determine how much time we have to avert a crisis and how quickly and by how much we should reduce our emissions today. What's to be done?
The world has to cut emissions faster and deeper. As the authors in the journal warn, the carbon budget is like a cake, much of which has been eaten by the developed world, leaving little for countries like India and China. For the budget to be adhered to, the industrialised countries have to lower their emissions dramatically. But this may not be enough to avert the crisis. Having been responsible for bringing the planet to the brink of a calamity because of their economic prosperity, the developed countries ought to help the emerging and developing economies to curtail their future emissions by assisting them with technology and funds.
How much do they need to pay out to help the developing countries cut emissions and adapt to climate change? India, China and other G77 countries have asked for 0.5-1% of the GDP of the industrialised countries to take dramatic emission reduction action. Considering that the GDP of the OECD (Organisation for Economic Co-operation and Development) countries in 2008 was $30.34 trillion, this works out to $150-300 billion. The amount seems huge, but compare it with the stimulus packages that the rich countries have committed recently to avoid a financial meltdown-the US alone will spend $268 billion in 2009 for economic recovery. The question Indian officials have raised at the international negotiations on climate change at the UN is worth repeating. If the rich countries can pour so much into their economies to save jobs, can't they put forth this relatively small amount to save millions from the disaster that their economies have created in the first place?
