<div>
<div>Paul et. al.:</div>
<div> </div>
<div>I sent this "Off List" to Paul, but I thought it might be of interest generally, and of course we don't want any pseudo-science being swallowed without question, now do we? Besides, Paul asked on Vision2020 for comments about the data on human CO2 contributions to global warming he gave from
clearlight.com...</div>
<div>--------------</div>
<div> </div>
<div>That web site you quoted claims that CO2's contribution to global warming is only about 3.6 percent, with water vapor at 95%. This web site presents their arguments backed up by references to "experts," some of whom are PhDs.
</div>
<div> </div>
<div>They also claim that the human contribution to atmospheric CO2 levels is 3.225%. This figure is very far off the generally accepted numbers, that pre-industrial CO2 levels were around 270 parts per million and are now around 370 parts per million (sources for these figures are given below), mostly due to human contributions, an increase of around 30% due to human impact, and at a level higher than at any other time in the past 650,000 years, according to a study of antarctic ice core's trapped air bubbles published in Science:
</div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.clearlight.com/~mhieb/WVFossils/greenhouse_data.html" target="_blank">http://www.clearlight.com/~mhieb/WVFossils/greenhouse_data.html</a></div>
<div> </div>
<div> </div>
<div>
<center>
<table height="225" cellspacing="1" cellpadding="1" width="360" border="1">
<tbody>
<tr height="44">
<td width="30%" height="44"><font size="-1">Based on concentrations (ppb) adjusted for heat retention characteristics</font></td>
<td align="middle" width="12%" height="44">Percent of Total</td>
<td align="middle" height="44"> Percent of Total --adjusted for <b><font color="#000000">water vapor</font></b></td></tr>
<tr>
<td width="30%"><font color="#ff0099"> </font><b><font color="#000000">Water vapor</font></b></td>
<td align="middle" width="12%"> -----</td>
<td align="right"><b> 95.000%</b></td></tr>
<tr height="24">
<td nowrap width="30%" height="24"> Carbon Dioxide (CO2)</td>
<td align="right" width="12%" height="24">72.369% </td>
<td align="right" height="24"><b> 3.618%</b></td></tr>
<tr height="24">
<td width="30%" height="24"> Methane (CH4)</td>
<td align="right" width="12%" height="24">7.100% </td>
<td align="right" height="24"><b> 0.360%</b></td></tr>
<tr height="24">
<td width="30%" height="24">Nitrous oxide (N2O)</td>
<td align="right" width="12%" height="24">19.000% </td>
<td align="right" height="24"> <b>0.950%</b></td></tr>
<tr height="24">
<td nowrap width="30%" height="24"> CFC's (and other misc. gases)</td>
<td align="right" width="12%" height="24">1.432% </td>
<td align="right" height="24"><b> 0.072%</b></td></tr>
<tr height="24">
<td align="middle" width="30%" height="24"> Total</td>
<td align="right" width="12%" height="24">100.000% </td>
<td align="right" height="24"> <b>100.000%</b></td></tr></tbody></table></center></div>
<div> --------</div>
<div> </div>
<div>The web site referenced above implies that the human sourced CO2 emissions argument for global warming often ignores the huge contribution of water vapor. Really? Read the data and arguments at these sites below:</div>
<div> </div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.eia.doe.gov/oiaf/1605/gg97rpt/chap1.html" target="_blank">http://www.eia.doe.gov/oiaf/1605/gg97rpt/chap1.html</a></div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.enviroliteracy.org/article.php/428.html" target="_blank">http://www.enviroliteracy.org/article.php/428.html</a></div>
<div> </div>
<div>---------</div>
<div> </div>
<div>Here is another human sourced global warming skeptic site, and here is their estimate of the impact of CO2 on global warming:</div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://brneurosci.org/co2.html" target="_blank">http://brneurosci.org/co2.html</a></div>
<div> </div>
<div>Carbon dioxide, although present in much lower concentrations than water, absorbs more infrared radiation than water on a per-molecule basis and contributes about 84% of the total non-water greenhouse gas equivalents [3], or about
4.2-8.4% of the total greenhouse gas effect. </div>
<div>---------</div>
<div>Note, though it is still much lower than the estimates of the scientists who insist CO2 has much more of an impact on global warming, this figure is at its high point estimates over twice the impact of the figure from
<a onclick="return top.js.OpenExtLink(window,event,this)" href="http://clearlight.com/" target="_blank">clearlight.com</a>.</div>
<div>---------</div>
<div>Recall that CO2 atmospheric concentrations are estimated to have gone up due to human contributions to the atmosphere, according to the Earth Sciences Institute, and many other sources, by about 30-35 percent, maybe a bit less, at this point in time. But we are only starting to dump CO2 into the atmosphere. In the next 50-100 years, we could dump huge amounts of CO2 into the atmosphere, increasing the human contribution to 50% or more of the total CO2 in the atmosphere. But even at this point in time, if CO2 amounts to at least 20% if the greenhouse effect, as many other experts estimate, as you can read below, the human impact is at least 6-7% added to the total greenhouse effect, if the percentage of CO2 impact on the greenhouse effect is close to 20%.
</div>
<div>--------</div>
<div>Consider these quotes on CO2 contributions to global warming, presenting a variety of percentages for the impact of water vapor vs. CO2 contributions to global warming: </div>
<div> </div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.pbs.org/wgbh/nova/ice/greenhouse.html" target="_blank">http://www.pbs.org/wgbh/nova/ice/greenhouse.html</a></div>
<div> </div>
<div> </div>
<div><font size="4">Each greenhouse gas has its own important role in trapping the sun's heat, the most significant of which is water vapor. On a clear day, water vapor can comprise 60 to 70 percent of the greenhouse effect. Next in line, carbon dioxide contributes an additional 25 percent. Some gases trap solar radiation from the sun better than others. For example, while man-made CFCs are one of the least plentiful gases, they actually have a greater relative impact than many others
</font></div>
<div><font size="4">----------------------</font></div>
<div><font size="4"></font> </div>
<div><font size="4"></font> </div>
<div><font size="4">Here is another source claiming water vapor is a much lower percentage of the greenhouse effect than <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://clearlight.com/" target="_blank">
clearlight.com</a>:</font></div>
<div><font size="4"></font> </div>
<div><font size="4"><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://encarta.msn.com/encyclopedia_761578504_3/Greenhouse_Effect.html" target="_blank">http://encarta.msn.com/encyclopedia_761578504_3/Greenhouse_Effect.html
</a></font></div>
<div><font size="4"></font> </div>
<div><font size="4"><b>Contributed By:</b><br>Michael Mastrandrea, B.S.<br><sub>Doctoral candidate, Department of Geological and Environmental Sciences, Stanford University; Department of Energy Global Change and Environment Program Fellow. Coauthor of
<i>The Role of Tropical Forest Conservation in Climate Change Mitigation.</i></sub></font></div>
<div>
<div>Stephen H. Schneider, B.S., M.S., Ph.D.<br><sub>Professor, Biological Sciences and Senior Fellow, Institute for International Studies, Stanford University. Editor, <i>Climatic Change</i>; author of <i>Global Warming: Are We Entering the Greenhouse Century?
</i></sub></div></div>
<div> </div>
<div><font size="4"></font> </div>
<div><font size="4">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr valign="baseline">
<td>A</td>
<td width="15">
<td>
<h3>Water Vapor</h3></td></td></tr></tbody></table>
<p><font size="2">Water vapor is the most common greenhouse gas in the atmosphere, accounting for about 60 to 70 percent of the natural greenhouse effect. Humans do not have a significant direct impact on water vapor levels in the atmosphere. However, as human activities increase the concentration of other greenhouse gases in the atmosphere (producing warmer temperatures on Earth), the evaporation of oceans, lakes, and rivers, as well as water evaporation from plants, increase and raise the amount of water vapor in the atmosphere.
</font></p>
<p><font size="2">-----------------</font></p>
<p><font size="2">And here is another site full of references to their sources that presents a far more complex view of the influence of "water vapor" vs. CO2 in global warming. This analysis strikes me as without an axe to grind in the global warming debate. It attempts to explore how complex the issue of how to measure the impact of water vapor and CO2 on global warming can be, and gives numbers based on different ways of measuring this impact from 36% to 88% (look at the info from both pages of the website), for CO2 between 9-26%:
</font></p>
<p><font size="2"><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.natexaminer.com/warming/gas.html" target="_blank">http://www.natexaminer.com/warming/gas.html</a></font></p>
<p><strong>Greenhouse gases</strong> (GHG) are gaseous components of the atmosphere that contribute to the greenhouse effect. The major natural greenhouse gases are water vapor, which causes about 36-70% of the greenhouse effect on Earth (not including clouds); carbon dioxide, which causes between 9-26%; and ozone, which causes between 3-7% (note that it is not really possible to assert that such-and-such a gas causes a certain percentage of the greenhouse effect, because the influences of the various gases are not additive. The higher ends of the ranges quoted are for the gas alone; the lower end, for the gas counting overlaps). [1] [2].
</p>
<p>------</p>
<p>And from the same web site at a different page:</p>
<p><font size="2"><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.natexaminer.com/warming/greenhouse.html" target="_blank">http://www.natexaminer.com/warming/greenhouse.html</a></font></p><font size="2">
<h2>Effects of various gases</h2>
<p>It is hard to disentangle the percentage contributions to the greenhouse effect by different gases, because their respective infrared spectrums overlap. However, one can calculate the percentage of trapped radiation remaining, and discover:
</p>
<center>
<table cellpadding="5" border="0">
<tbody>
<tr>
<th bgcolor="#896ed5">Species<br>removed</th>
<th bgcolor="#896ed5">% trapped radiation<br>remaining</th></tr>
<tr>
<td bgcolor="#cac8d5">All</td>
<td bgcolor="#cac8d5">0</td></tr>
<tr>
<td bgcolor="#cac8d5">H2O, CO2, O3</td>
<td bgcolor="#cac8d5">50</td></tr>
<tr>
<td bgcolor="#cac8d5">H2O</td>
<td bgcolor="#cac8d5">64</td></tr>
<tr>
<td bgcolor="#cac8d5">Clouds</td>
<td bgcolor="#cac8d5">86</td></tr>
<tr>
<td bgcolor="#cac8d5">CO2</td>
<td bgcolor="#cac8d5">88</td></tr>
<tr>
<td bgcolor="#cac8d5">O3</td>
<td bgcolor="#cac8d5">97</td></tr>
<tr>
<td bgcolor="#cac8d5">None</td>
<td bgcolor="#cac8d5">100</td></tr></tbody></table></center>
<p>(Source: Ramanathan and Coakley, Rev. Geophys and Space Phys., 16 465 (1978)); see also [3].</p>
<h3>Water vapor effects</h3>
<p>Water vapor is the major contributor to Earth's greenhouse effect. Its effects vary due to localized concentrations, mixture with other gases, frequencies of light, different behavior in different levels of the atmosphere, and whether positive or negative feedback takes place. High humidity also affects cloud formation, which has major effects upon temperature but is distinct from water vapor gas.
</p>
<p>The IPCC TAR (2001; section 2.5.3) reports that, despite non-uniform effects and difficulties in assessing the quality of the data, water vapor has generally increased over the 20th Century.</p>
<p>Estimates of the percentage of Earth's greenhouse effect due to water vapor:</p>
<ul>
<li>36% (table above)
<li>60–70% Nova. <em>Greenhouse—Green Planet</em> [4] </li></li></ul>
<p>Including clouds, the table above would suggest 50%. For the cloudless case, IPCC 1990, p 47–48 estimate water vapor at 60–70% whereas Baliunas & Soon estimate 88% [5] considering only H2O and CO2. Water vapor in the troposphere, unlike the better-known greenhouse gases such as CO2, is essentially passive in terms of climate: the residence time for water vapor in the atmosphere is short (about a week) so perturbations to water vapor rapidly re-equilibriate. In contrast, the lifetimes of CO2, methane, etc, are long (hundreds of years) and hence perturbations remain. Thus, in response to a temperature perturbation caused by enhanced CO2, water vapor would increase, resulting in a (limited) positive feedback and higher temperatures. In response to a perturbation from enhanced water vapor, the atmosphere would re-equilibriate due to clouds causing reflective cooling and water-removing rain. The contrails of high-flying aircraft sometimes form high clouds which seem to slightly alter the local weather.
</p>
<p>-----------------------------------</p></font>
<p><font size="2">Now we have radically different numbers given for a fundamental issue in the whole global warming debate, water vapor contributions vs. CO2, numbers backed up by credentialed sources. Who is right?</font>
</p>
<p>Consider one factor mentioned several times in the discussions and arguments and "data" presented above: human sourced CO2 can warm the atmosphere, causing a feedback loop to increase water vapor. Thus the effects of water vapor can become part of the human caused global warming problem.
</p>
<p>I think the answer to the question lies in part in the well documented empirical data about the melting of ice packs (the Arctic is undergoing dramatic melting as is Greenland) and glaciers around the world, the changes in the migration and maturation patterns of life forms, many of which are responding to warmer and earlier Springs by altering their behavior in very profound ways, and the clustering of warm years in recent times, with 5 of the warmest years on record since 1890 all from 1998-2005, which I know by itself could just be a random "clustering:"
</p>
<p>Info on warmest years since 1890:</p>
<p><a href="http://www.nasa.gov/vision/earth/environment/2005_warmest.html">http://www.nasa.gov/vision/earth/environment/2005_warmest.html</a></p>
<p>--------</p>
<p>A published peer reviewed study, results of which I posted to Vision2020, was done recently showing that earlier Springs at high elevations in the forests of the Western US are the primary cause of increased forest fire intensity and duration due to increased and earlier drying of tinder due to global warming melting winter snow packs earlier in the season. The authors of the study said they were not even looking at global warming, but the data led them to this variable.
</p>
<p>Of course it can be argued that these significant changes are just a natural cycle of some sort. But these changes are sudden (in the grand time scale of the planet) and dramatic, and must be caused by some variable or variables. We can examine the dominate climate change variables. We can measure output from the sun, the content of water vapor in the atmosphere, the greenhouse gases, the contribution of albedo, the effects of cloud cover. We know of the variations in the Earth's orbit, precession of the equinoxes, and of the influence of volcanoes and aerosols. We can estimate influences of farming and animal food impacts, along with deforestation. We understand how plants and the ocean absorb CO2, how natural methane releases occur, and the potential impacts of methane hydrates, etc. etc.
</p>
<p>While climate change is far from a perfect science, the evidence points quite clearly that the main variable that is causing these sudden and very significant changes to the Earth's climate is mostly human contributions of CO2 to the atmosphere, though some argue farming and deforestation should be considered more in the human impact on climate change.
</p>
<p>If we continue this pattern, increasing atmospheric CO2 by hundreds of parts per million, to levels 100% or more above pre-industrial levels, we may induce severe climate change. This is not worth the risk to experiment with, in my opinion.
</p>
<p>Of course there are numerous other reasons to conserve fossil fuels, the most important being, they are finite, besides being controlled by "enemy" states, and economic and other disruptions of great magnitude are possible if we do not conserve and prepare for the end of the age of fossil fuels, coming in just a couple of hundred years, given an optimistic outlook on accessible resources. The later reason alone is sufficient reason to enact radical conversation of fossil fuels, forgetting global warming.
</p>
<p>Ted Moffett</p></font></div>
<div> </div>
<div> </div></div>