In 2010 this was agreed on as the goal, subject to periodical review. This year at COP21 is the first time that the outcome of the review has officially been discussed. This debate proved to be a critical component of the negotiations.
Our current warming level of 0.8 degrees Celsiusis already increasing the havoc in our lives [1].
Over the last 20 years, at least 606,000 people have died as a result from weather extremes, exacerbated by climate change and 7 million people die annually from the very air pollution that creates climate change.
Natural disasters such as Storm Desmond and the Chennai floods are becoming more extreme and more common. While these break the news headlines, they also break hearts, homes, and families.
The stark projections of impacts from 2 degrees Celsius of warming depict a worse future for all.
Yet the elderly, children, and the world's more disadvantaged communities stand to lose the most.
Who will look into the eyes of the Sub-Saharan farmer whose crops are destroyed by drought? Who will tell the Pacific Island child that the ocean has swallowed their home? How will New Zealand farmers cope with even more droughts and floods?
While the difference between 1.5 and 2 degrees Celsius sound barely distinguishable, this half a degree is highly significant.
At 1.5 degrees Celsius we may still be able to preserve up to half of coral reefs, and keep sea level rise to below 1 metre.
We may maintain some Arctic sea ice, and prevent species extinctions. Yet at 2 degrees Celsius these things will no longer be possible [1].
Outcomes for global health and food security are significantly different, too. At 2 degrees Celsius, there would be significant barriers to sustainable development, risk to crop production, and human health.
While the argument over 1.5 versus 2 remains strong, this is not so much a matter of science. It's a conflict based in values, threats to different ways of life, and a broad spectrum of vulnerability to risk.
The Paris Agreement has delivered a compromise on this issue. We now see a deal that "aims to strengthen the global response to the threat of climate change by holding the increase in the global average temperature to well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 degrees Celsius above pre-industrial levels."
While the wording allows both temperature goals a space, this outcome was welcomed by 195 countries within the UNFCCC. Government minister, Dr James Fletcher of St Lucia expressed his gratitude saying, "I can return home to the citizens of my country and reassure them that the world cares about them... I can tell the young people in our region who adopted "1.5 to stay alive" as their mantra that their future looks much brighter today than it did two weeks ago."
The intention may be there, but it is now time to walk the talk. Although the outcomes of the temperature difference are poles apart, the necessary action is surprisingly similar. The technology required is the same; it is simply a matter of increasing the rate of deployment.
The costs of action are not out of reach, either. For a 2 degrees Celsius future, it has been estimated to cost 0.06% GDP over the 21st Century, as opposed to 0.1% GDP. This will not cripple economic growth. In real terms, taking the 1.5 degrees Celsius path means that it will take four years longer to reach the same level of economic wealth over the 90 year period of 2010 - 2100, as opposed to two years on the 2 degrees Celsius track.
These costs do not recognise the benefits of avoiding expensive damages and loss of life, which can offset the costs entirely. A 1.5 degrees Celsius future is still obtainable. We don't need to, and cannot, wait for anything.
New Zealand has a history of standing up for what is right. Let's continue honouring the likes of Kate Sheppard and Sir Edmund Hillary. Let's stand up for our Pacific neighbours and increase our emission reduction pledge to one that is in line with a 1.5 degrees Celsius - or even 2 degrees Celsius world - as opposed to a 3-4 degrees Celsius world. While it is great to see NZ committing financial aid to the Pacific, we can go further than aid money. Give a person a fish and you'll feed them for a day. Work to prevent climate change, and fish stocks may survive to feed them into the future.
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