A changing climate in Copenhagen

I’ve just returned from a major climate meeting in Copenhagen with a mixture of emotions.  Attended by more then 2000 scientists, the aim was to pull together the very latest in climate change science since the Intergovernmental Panel on Climate Change (better known as the IPCC) made their 2007 Fourth Report on the past, present and future world’s climate. Although the IPCC Fourth Report was an impressive summary of the worrying state of climate, its conclusions were based on science that was published before 2005. Since then a staggering amount of new work has been generated. Given the pace of research and the speed at which change is happening on the ground, this was a fantastic meeting to catch up on the latest thinking. Regardless of whether you attended, you can watch many of the key lectures by going to the conference website.  They’re a great resource for anyone interested in climate change. 

Copenhagen negotiations
In the IPCC report, a number of different economic scenarios are set out over the next century.  These provide a range of different emission rates of greenhouse gases which are then fed into the global climate models.  The scenarios range from a low-emission future where population growth is relatively slow and economic and environmental solutions are sorted out at a local level, through to the so-called ‘business-as-usual’ scenario, something akin to ‘let’s have a party as the ship goes down’.   Because it takes some time before the extra heat trapped by the earth is given up to the atmosphere, the climate changes envisaged under these different scenarios are broadly similar over the next couple of decades.  But after about 2050 the differences between these scenarios start to play out through the climate system. So much so that by the end of this century, the low emission scenarios predicts a temperature rise of around 1.8˚C relative to 1990 but the ‘business-as-usual’ suggests something on the order of 4˚C. The question posed at the recent Copenhagen was: are these projections consistent with the latest science?

Unfortunately not. Almost everything I heard pointed to rates of change that mapped on or above the trajectories that lead to high-level change. I don’t think I was alone in feeling the atmosphere was quite surreal.  Top flight scientists seemed to almost nonchalantly describe the oceans becoming more acidic, species becoming extinct, long-term (mega-) droughts and massive sea level rises. Some of these impacts are already happening or will do so within the lifetime of many of those attending.  There was a bizarre matter-of-factness about the grim news. I co-chaired one session on lessons from the past and we heard researcher after researcher describe changes that our planet hasn’t seen for millions of years. 

The timing for the meeting was well chosen. At the end of this year, world leaders and their negotiators will meet in the same conference center in Copenhagen to thrash out a new deal to stabilize greenhouse gas levels after 2012 when the Kyoto Protocol expires. In spite of much that was said, there were some rays of hope. It’s clear that adaptation and mitigation are still possible. In the session I helped organize we heard of archaeological lessons where people around the world had faced similar changes (albeit on a local or regional scale) and managed to successfully negotiate the hurdles they faced.  At a national level, we learnt how Denmark has driven down it’s greenhouse gas emissions by investing in renewables (some 13 per cent relative to 1990 levels) and in the process opened up a huge new market.  Danish companies control a phenomenal one-third of the global wind market. There’s a big lesson here.  


We have to remember we can change our ways.  We don’t have to follow the path we’re on.  We have the know-how to cut our emissions and get greenhouse gas levels down.   As the climate changes, new ‘green’ industries are developing with increasing pace.  Opportunities are opening up to develop energy independence and other endeavours.  A more sustainable path is becoming possible. With real political leadership, there could be real hope. The time is right for change.  Let’s grab it.

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