Steve Hurley writes the Explaining Science blog, and we have featured his work over the years. He has been writing recently about COP 28 and carbon dioxide. His post began:

“Like many of you, in December last year I followed with interest the news reports from COP28. As it concluded, there was much written in the media about whether the nations of the world would actually do what is needed to restrict the rise in average global temperature to 1.5 degrees Celsius above pre-industrial levels. Now that a month has passed, the media’s attention has faded a little, particularly with all the other events happening across the globe.

However the question still remains:

Will humanity do enough over the coming decades to reduce emissions of greenhouse gases (the most important of which is carbon dioxide) ?

My pessimistic view is that this won’t happen. In the past decades, short term national interest has taken priority over doing what is needed to reduce global warming.  A good illustration that not enough has been done is the graph below. This shows the annual average carbon dioxide levels for the years from 1990 to 2022

Since 1995, there have been 28 United Nations COP conferences and despite all the discussion amongst the tens of thousands of participants (COP28 had 85 000 who flew in from all around the world) the rise in global carbon dioxide levels has continued at a steady rate of two parts per million per year. It appears that despite all the discussions which have happened at these conferences this hasn’t resulted in effective action. If we look at all the previous COP conferences two in particular stand out.

  • COP3 in 1997, which adopted the Kyoto Protocol in which most industrialised countries agreed to reduce their greenhouse gas emissions by an average of 6 to 8% below 1990 levels between the years 2008–2012. However the US government did not ratify the agreement on the grounds that it would damage the US economy.
  • COP21 in 2015, which adopted the Paris agreement. Participants agreed emissions should be reduced as soon as possible and reach net zero by 2050. Each party to the Paris Agreement was required to establish a Nationally Determined Contribution (NDC). a climate action plan to cut greenhouse gas emissions, and update it every five years. 
  • On June 1, 2017, US President Donald Trump announced that the United States would cease participation in the Paris Agreement stating that the agreement undermines the U.S. economy. This decision was reversed following the election of Joe Biden.


The rest of the post can be read here.


Reading the post illustrates the huge challenge facing anyone trying to make sense of global warming, and particularly those trying to educate the young. Part of the challenge is that the science (what’s happening / how does it happen / how fast is it happening) and what we might sensibly do about it (practical socio-economic steps) are inevitably intertwined. Whilst the “what / how” of global warming is understood and very broadly agreed, the speed of the change that we shall likely experience is contested as this largely depends on which future projection is chosen – and there are plenty to choose from, even within the IPPC reports. Maybe Steve will write about this.

Leave a Reply

Your email address will not be published. Required fields are marked *

Post comment