‘...the average temperature of the Earth’s land has risen by 1.5 °C over the past 250 years. The good match between the new temperature record and historical carbon dioxide records suggests that the most straightforward explanation for this warming is human greenhouse gas emissions.’
Diagram provided by permission of Berkeley Earth
So we have the final acceptance that the Earth is warming and that human greenhouse gas emissions are the cause. The sceptical scientists who led this study should be applauded for sticking to the rigour of the science and accepting that their earlier views were mistaken. The bandwagon of climate change deniers should now disperse and people like Nigel Lawson, a clever man who for whatever reason decided to fight against action to address climate change, should retire gracefully and hope people forget his rather silly campaign. The problem is that this is a not an Oxford Union debate in which people win or lose an argument on the merits of their oratory skills; this is about facts and the future of humanity. Climate scientists have not always been the strongest debaters. Many sceptics have outstanding skills at holding the attention of an audience. They have succeeded in putting doubt into people’s mind and injecting delay into the world efforts to take action.
Let us reflect on how long the delay has been. In 1990, I was working with climate scientists, and global warming was understood and it was known that fossil carbon emissions through human activity were the cause, but policy makers needed to be persuaded.
In 1990, the IPCC’s first report concluded:
•’Anthropogenic climate change will persist for many centuries.’
•’Further action is required to address remaining gaps in information and understanding.’
In 1995, the IPCC’s second report concluded:
‘The balance of evidence suggests a discernible human influence on global climate.’
In 2001, the IPCC’s third report concluded:
‘In light of new evidence and taking into account the remaining uncertainties, most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations. Furthermore, it is very likely that the 20th Century warming has contributed significantly to the observed sea level rise... and widespread loss of land ice.’
The 2001 report, after over a decade of work, nailed just about all we need to know about climate change but still the sceptics persisted to oppose the science.
How can it have taken 22 years to get this accepted? Will we now, finally, leap into action?