Site icon Fabius Maximus website

No significant warming since 1995

More fruits from ClimateGate, the glasnost in climate science following the liberation of many emails and documents from the UK’s Climate Research Unit.

Q&A: Professor Phil Jones“, BBC, 13 February 2010 –BBC’s environment analyst Roger Harrabin intereviews Phil Jones, director of the Climatic Research Unit (CRU) at the University of East Anglia (UEA), which has been at the centre of the row over hacked e-mails.

Question: Do you agree that from 1995 to the present there has been no statistically-significant global warming

Dr. Jones:  Yes, but only just. I also calculated the trend for the period 1995 to 2009.  This trend (0.12C per decade) is positive, but not significant at the 95% significance level.  The positive trend is quite close to the significance level.  Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods.

Question:  Do you agree that from January 2002 to the present there has been statistically significant global cooling?

Dr. Jones:  No. This period is even shorter than 1995-2009.  The trend this time is negative (-0.12C per decade), but this trend is not statistically significant.

Question:  There is a debate over whether the Medieval Warm Period (MWP) was global or not. If it were to be conclusively shown that it was a global phenomenon, would you accept that this would undermine the premise that mean surface atmospheric temperatures during the latter part of the 20th Century were unprecedented?

Dr. Jones:   There is much debate over whether the Medieval Warm Period was global in extent or not. The MWP is most clearly expressed in parts of North America, the North Atlantic and Europe and parts of Asia. For it to be global in extent the MWP would need to be seen clearly in more records from the tropical regions and the Southern Hemisphere. There are very few palaeoclimatic records for these latter two regions.  Of course, if the MWP was shown to be global in extent and as warm or warmer than today (based on an equivalent coverage over the NH and SH) then obviously the late-20th century warmth would not be unprecedented. On the other hand, if the MWP was global, but was less warm that today, then current warmth would be unprecedented.

Other articles about recent climate trends

  1. What happened to global warming?“, BBC, 9 October 2009
  2. World will ‘cool for the next decade’“, New Scientist, 9 September 2009 — Summary of forecasts about decadal cooling (e.g., “Advancing decadal-scale climate prediction in the North Atlantic sector“, Mojib Latif et al, Nature, 1 May 2008
  3. Climatologists Baffled by Global Warming Time-Out“, Der Spiegel, 19 November 2009
  4. World may not be warming, say scientists“, The Times, 14 February 2010

For more information from the FM site

To read other articles about these things, see the FM reference page on the right side menu bar, including About the FM website page. Of esp relevance to this topic:

Posts about global cooling

  1. More forecasts of a global cooling cycle, 15 July 2008
  2. Good news about global warming!, 21 October 2008
  3. One of the most interesting sources of news about science and nature!, 27 October 2008
  4. An important letter sent to the President about the danger of climate change, 21 October 2009
  5. About those headlines from the past century about global cooling…, 2 November 2009
  6. A look at global warming written in a cooler and more skeptical time, giving us a better understanding of climate science, 23 November 2009
  7. The facts about the 1970’s Global Cooling scare, 7 December 2009

Afterword

Please share your comments by posting below.  Per the FM site’s Comment Policy, please make them brief (250 word max), civil and relevant to this post.  Or email me at fabmaximus at hotmail dot com (note the spam-protected spelling).

Also — you can now subscribe, receiving posts by email — see the box on the upper right.

Exit mobile version