Climate change: What are we trying to achieve in Paris?

If “nice weather” is your favourite ice-breaker when you meet someone, you better start thinking of something else to say. Thanks to climate change, the weather is no longer so nice in many places. Think Chennai this week.

But what is climate change?
Since the Industrial Age began nearly 200 years ago, human activity around the world, but especially in the industrialized countries, has  caused the earth to warm up, which we now call Global Warming. It refers to the overall warming of the planet, based on average temperature over the entire surface of the earth. Global Warming happens mainly due to carbon dioxide, but also some other gases that are collectively called greenhouse gases (GHGs), released when we burn fossil fuels such as coal, oil, natural gas, etc., to produce electricity or goods or to power our vehicles, etc. Even agricultural activity produces GHGs. These gases trap sunlight, instead of reflecting it back into space, and so heat up the atmosphere. The warming earth’s atmosphere is causing climate change, such as changes in weather patterns, unseasonal rains, and severe weather events such as the Chennai rains last week.

What’s the worry?
The earth’s temperature has risen by nearly 1 degree Celsius since around 1850, and the pace of that rise has increased in the past few decades. It has been estimated that if the temperature rises by more than another degree Celsius, climate change will have disastrous effects on the planet and all of us. The world’s food production will be hit, we will see more extreme events such as the Chennai rains, Tsunamis, etc., diseases caused by germs will become more severe and widespread, many island nations will sink into the oceans, and so on.  We must therefore begin to curb carbon emissions, the main culprit in global warming, to ensure that the earth does not heat up by more than another degree Celsius before 2100, or by 2 degrees Celsius cumulatively between 1850 and 2100.

So, how much more carbon can we put into the atmosphere safely?
According to the Inter-governmental Panel on Climate Change (IPCC), that limit is 2,900 billion tonnes. Of that, some 1,900 billion tonnes have already accumulated in the atmosphere since 1850. So, the world collectively has a ‘Carbon Space’ of 1,000 billion tonnes of carbon dioxide that we can emit into the atmosphere until about 2100.

So, we can still burn fossil fuels, drive guzzler SUVs, etc., for some more decades then?
No, and that’s why climate change is now called a crisis. At the rate at which the human race is emitting carbon, we are on track to exhaust the 1,000 billion tonnes limit by as early as 2030 if we do not act now. That’s why more than 150 countries, including the biggest polluters China, US, the European Union, India, etc., are all pledging to cut their carbon emissions.      

So, what’s the fight about in Paris?
It’s about who should bear more responsibility and more burden for cutting carbon emissions, and it’s about dividing up the remaining carbon space fairly. Industrialized countries such as the US have been most responsible for the carbon emissions so far and continue to be so. They are also the ones that are rich enough to fund development of new green technologies as well as fund poorer countries to adopt them. Developing countries, led by India, are demanding that the rich countries do more. The US and other rich nations are pressuring developing countries to do more to cut carbon emissions while their own plans to cut their emissions are not ambitious enough.

(Rakesh Kamal is Programme Officer, Climate Change Programme, at the Centre for Science and Environment, New Delhi)