Why is there so much preoccupation with atmospheric CO2 concentrations and reducing anthropogenic CO2 emissions when it is well documented in the peer-reviewed scientific literature that the CO2 contribution to the overall greenhouse effect is so weak that it can be easily supplanted by small changes in clouds and water vapor, or natural climate-changing constituents?


Tuesday, 4 June 2013

'Facts, Not Fear': talking with children about the prospect of a warmer planet.

The book ‘Facts, Not Fear’ covers many eco-alarms, and shows in each case how the sting may be removed from them by the simple expedient of noting contrary evidence and the informed views of subject-matter experts who are not alarmed.  

Chapter 13, entitled ‘A Hotter Planet?’ addresses the global warming scare, using the same structure deployed for the other alarms.  I will try to convey that structure here, using extracts from Chapter 13.

The authors lead-in with quotes illustrative of the alarm.  This sets the scene, and starts from where most readers are likely to be, given the extent to which such views have been promoted in recent decades.  Here is an example they use from the magazine Maclean’s in 1995:

“Imagine a world of relentlessly rising temperatures, where farmlands are scorched into desert and inland waters like the Great Lakes shrink in the heat.  As global warming intensifies, the polar ice caps dissolve and ocean levels rise by more than 100 feet, swamping low-lying islands and coastal areas. Vancouver, Halifax, New York City, Amsterdam, Shanghai and other port cities are inundated.  As the global floodwaters rise, more than a quarter of the world’s population is displaced.”

They take a closer look at some of the claims
‘It is true that over the past 100 years, the Earth has become slightly warmer, but only by about half a degree Celsius or 1 degree Fahrenheit. ‘
‘… most of the warming occurred before most of the greenhouse gases were put in the atmosphere’
‘As for the future, scientists do not know if the Earth will continue to get warmer.  If it does, the increase may be so slight as to be hardly noticeable.’
‘Recent studies have predicted a possible rise in sea level of six to forty inches, not feet.’
‘Temperature predictions, too, have moderated.’
‘..measurements of temperature taken by satellites (rather than measurements close to the ground) showed no warming between 1979 and mid-1996 …In fact there was a slight cooling trend..’

They take a closer look at some of the science
‘Some years ago, scientists decided to see what would happen if they assumed CO2 had doubled, as they thought it would by the end of the twenty-first century.  The result: significantly higher temperatures, higher by between 2 and 5 degrees Celsius.  The projections looked scientific. But scientists know that these computer models of the world’s climate have strengths and weaknesses … they miss entirely the effects of mountains such as the Rockies, the Sierra Nevadas and the Cascades.  According to these models, the climate of heavily forested Oregon and the climate of the Nevada desert would be about the same…Another problem is that scientists are really guessing about how different aspects of the climate affect one another.  For example:
# Water vapour is far more important than carbon dioxide in trapping heat.  Carbon dioxide will increase temperatures significantly only if water vapour increases significantly.  But will it?
# Clouds (composed of water vapour that has condensed into droplets) may increase if carbon dioxide goes up.  Some clouds increase the warming effect and others decrease it by reflecting sunlight back into space
# Oceans and vegetation absorb CO2, but how much, how fast, and for how long?  No one knows.
..Another problem is that the pattern of warming does not follow the rise in CO2 …’

They articulate a calmer perspective
‘Children’s textbooks, reflecting the popular view, discuss only the negative impacts of warming.  But some scientists note that if the world gets warmer, that would not be all bad.
# “In fact,” says Andrew Solow, a scientist at Woods Hole Oceanographic Institute, “there is some irony in the description of global warming as problematic, since it is not unreasonable to view human history as a struggle to stay warm.”
# Thomas Gale Moore, a prominent economist at the Hoover Institution, has even concluded that warmer weather would reduce deaths from heart disease and respiratory illness.  Cold temperatures lead to death more often than hot ones.
# More carbon dioxide in the air will benefit many plants.  It causes more luxuriant plant growth, larger flowers, and great crop yield.  Some scientists think that rising levels of CO2 in the air have already contributed to the Green Revolution, that is, to the remarkable increases in food production of the past few decades.”

The chapter finishes with two headings that are used in each of the specific-topic chapters: ‘Talking to Your Children’ and ‘Activities for Parents and Children’.  Here are extracts from these:

‘Talking to Your Children’
‘It is little wonder that our children are frightened.  We would be, too, if we read the textbooks our children do.  But now you can give your children a more balanced picture.
# Is the world going to get hotter?
   No one really knows.  Carbon dioxide keeps heat from being emitted into space and, because carbon dioxide is increasing in the atmosphere, temperatures may get warmer.  However, the warming may be so small as not be noticeable by the average person.
# Are human activities causing global warming?
  Perhaps.  By burning fossil fuel, humans add carbon dioxide to the atmosphere, and more carbon dioxide should keep more heat in the Earth’s atmosphere.  But the increase in warmth may be very small since many, many factors affect climate. Until recently, some scientists were more worried about a coming Ice Age than too much warming.
# Has the world been getting hotter?
  Yes, a little.  Scientists think that the Earth’s average temperatures have increased by between three- and six-tenths of a degree Celsius or between one-half and one degrees Fahrenheit over the past one hundred years.  But the increases have been irregular, not steady, and it may simply reflect natural variation in temperatures over time.
# Is carbon dioxide harmful?
  No.  In fact, it is a beneficial part of the atmosphere.  It provides food for plants.  More carbon dioxide in the atmosphere should increase plant growth.  This will increase the amount of oxygen from plants through photosynthesis.’

 ‘Activities for Parents and Children’
The authors give three suggestions for helping ‘reassure your children that the world is not “out of control”’:
i) Visit a library and study books about dinosaurs, and note that in that era: ‘the Earth has an atmosphere that contained carbon dioxide levels that were five to ten times greater than now …The Earth was warmer and wetter, not burning up or drying out. (At other times, however, high carbon dioxide levels coexisted with cold temperatures).  The point is that the image of global warming that many people hold may be unnecessarily grim.’
ii) Visit a commercial greenhouse.  You can explain that the way they work is nothing like the so-called greenhouse effect. 
‘Ask the greenhouse manager to explain how conditions in the greenhouse are controlled to help plants grow.  Does this greenhouse add carbon dioxide?  Why or why not?’
iii) Another trip to the library.  ‘Doomsday predictions of climate change are nothing new.  Your children may not be aware that in the mid-1970s many people worried about the coming Ice Age’.  Suggestions are then given for articles and books to look up.

My take
That is a very appealing structure and style.  It would be easy to find even more melodramatic quotes to kick it off, and easy to find more criticisms* of the case for climate alarm.  But they could easily result in a much harsher or more strident tone, and be less suited for the intended use of helping children.   I think the gentle, but purposeful and highly-focused approach taken by the authors of this book has much to commend it.  It would be counter-productive to try to be too comprehensive or too hard-hitting.  Any such book will not be the last word on any of these issues, but a book such as this one could well be the inspiration for some children at least to do a lot more reading of other sources.  And it may just be sufficient for most of them to take the sting out of the alarming materials that are so readily encountered about human influence on the climate system.

* Note added 05 June 2013  A recent listing of failings of this case is presented here: http://icecap.us/index.php/go/new-and-cool/agw_theory_has_failed_all_tests_so_alarmists_return_to_the_consensus_hoax/

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