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	<title>Comments on: Multi-Decade Climate Cycles</title>
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		<title>By: Mesa Econoguy</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1555</link>
		<dc:creator>Mesa Econoguy</dc:creator>
		<pubDate>Thu, 08 May 2008 00:15:53 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1555</guid>
		<description>&lt;p&gt;Note to all:&lt;/p&gt;

&lt;p&gt;Peer reviewed AGW “science” is meaningless.&lt;br /&gt;
&lt;/p&gt;

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		<content:encoded><![CDATA[<p>Note to all:</p>
<p>Peer reviewed AGW “science” is meaningless.</p>
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		<title>By: Scientist</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1554</link>
		<dc:creator>Scientist</dc:creator>
		<pubDate>Tue, 06 May 2008 16:52:56 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1554</guid>
		<description>&lt;p&gt;No, there aren&#039;t well-founded doubts.  None appear in the scientific literature, although of course you will find no shortage of politically motivated, scientifically questionable blogs on the subject.  In reality, whether you look at GISS data, Hadcrut, RSS or UAH, there is a warming trend over the last thirty years of 0.15-0.2&#176;C/decade.&lt;/p&gt;

&lt;p&gt;Temperatures are not increasing?  What makes you think that?  Which data set shows this, and over what timescale?&lt;/p&gt;

&lt;p&gt;Yes, we do see the evidence of positive feedbacks in the real world.  Northern polar regions are warming far more rapidly than anywhere else, due to one particular feedback.  Ice ages could not occur without positive feedback, and they could not end without it either.&lt;/p&gt;

&lt;p&gt;It looks very much like you are taking a position which is not based on the evidence.  Simple numbers show that CO2 forcing dominates.  I do not see you showing how any other forcing is currently comparable to CO2 forcing, or arguing that my numbers were wrong, I just see you vaguely stating some misconceptions which find no support at all in the peer-reviewed literature.&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>No, there aren&#8217;t well-founded doubts.  None appear in the scientific literature, although of course you will find no shortage of politically motivated, scientifically questionable blogs on the subject.  In reality, whether you look at GISS data, Hadcrut, RSS or UAH, there is a warming trend over the last thirty years of 0.15-0.2&deg;C/decade.</p>
<p>Temperatures are not increasing?  What makes you think that?  Which data set shows this, and over what timescale?</p>
<p>Yes, we do see the evidence of positive feedbacks in the real world.  Northern polar regions are warming far more rapidly than anywhere else, due to one particular feedback.  Ice ages could not occur without positive feedback, and they could not end without it either.</p>
<p>It looks very much like you are taking a position which is not based on the evidence.  Simple numbers show that CO2 forcing dominates.  I do not see you showing how any other forcing is currently comparable to CO2 forcing, or arguing that my numbers were wrong, I just see you vaguely stating some misconceptions which find no support at all in the peer-reviewed literature.</p>
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		<title>By: Industry Insider</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1553</link>
		<dc:creator>Industry Insider</dc:creator>
		<pubDate>Tue, 06 May 2008 13:41:08 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1553</guid>
		<description>&lt;p&gt;To believe there is a current rise in temperatures of about 0.2 C per decade, one has to believe the various adjustments to the temperature record are valid, and I note that there are some well-founded doubts about that.  It is clear that non-CO2 factors are driving the climate system because temperatures are not increasing.  The past 10 years of temperature data and projections for the next 10 years illustrate the importance of the non-CO2 factors (e.g., solar factors and oscillations) as the primary determinants of global temperature.  As has been discussed ad nauseam here and elsewhere, in order for CO2 to result in large, catastrophic temperature changes, the climate system would have to be dominated by positive feedback mechanisms (meaning the sum of the various positive and negative feedbacks would be positive and large), and we are not seeing the evidence for that in the real world.&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>To believe there is a current rise in temperatures of about 0.2 C per decade, one has to believe the various adjustments to the temperature record are valid, and I note that there are some well-founded doubts about that.  It is clear that non-CO2 factors are driving the climate system because temperatures are not increasing.  The past 10 years of temperature data and projections for the next 10 years illustrate the importance of the non-CO2 factors (e.g., solar factors and oscillations) as the primary determinants of global temperature.  As has been discussed ad nauseam here and elsewhere, in order for CO2 to result in large, catastrophic temperature changes, the climate system would have to be dominated by positive feedback mechanisms (meaning the sum of the various positive and negative feedbacks would be positive and large), and we are not seeing the evidence for that in the real world.</p>
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		<title>By: Al Fin</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1552</link>
		<dc:creator>Al Fin</dc:creator>
		<pubDate>Tue, 06 May 2008 01:51:33 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1552</guid>
		<description>&lt;p&gt;And as temperatures continue to drop, we find CO2 changing from positive forcing to a negative forcing.  Of course GISS will continue faking temperature readings as long as it can, but such humbuggery can only last so long in a modern world.&lt;/p&gt;

&lt;p&gt;When the modelers finally begin to realize they have been doing their calculations based upon humbuggered data, it will be time for the fat lady to sing.&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>And as temperatures continue to drop, we find CO2 changing from positive forcing to a negative forcing.  Of course GISS will continue faking temperature readings as long as it can, but such humbuggery can only last so long in a modern world.</p>
<p>When the modelers finally begin to realize they have been doing their calculations based upon humbuggered data, it will be time for the fat lady to sing.</p>
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		<title>By: Scientist</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1551</link>
		<dc:creator>Scientist</dc:creator>
		<pubDate>Mon, 05 May 2008 17:32:18 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1551</guid>
		<description>&lt;p&gt;And following the forcing calculation with a temperature calculation, using 0.75°C/W/m² you get 0.25°C and 0.36°C.  The difference is 0.1°C; this is well within the range of interannual variation that is caused by internal variability.  It is not a great surprise that this rise in CO2 forcing did not lead to an uninterrupted rise in temperatures; other factors can easily offset that forcing.  The forcing today relative to 1850 from CO2 is about 1.7W/m², and this forcing is now the largest operating.&lt;/p&gt;

&lt;p&gt;The effect of oscillations averages out to zero, by definition.  You cannot explain the secular upward trend in temperatures by recourse to these oscillations.  The current rise in temperatures of about 0.2°C per decade is exactly in line with expectations given the rising concentrations of CO2 and the smaller effect of all the other forcings.&lt;/p&gt;

&lt;p&gt;Which factors do you believe are more important than CO2?&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>And following the forcing calculation with a temperature calculation, using 0.75°C/W/m² you get 0.25°C and 0.36°C.  The difference is 0.1°C; this is well within the range of interannual variation that is caused by internal variability.  It is not a great surprise that this rise in CO2 forcing did not lead to an uninterrupted rise in temperatures; other factors can easily offset that forcing.  The forcing today relative to 1850 from CO2 is about 1.7W/m², and this forcing is now the largest operating.</p>
<p>The effect of oscillations averages out to zero, by definition.  You cannot explain the secular upward trend in temperatures by recourse to these oscillations.  The current rise in temperatures of about 0.2°C per decade is exactly in line with expectations given the rising concentrations of CO2 and the smaller effect of all the other forcings.</p>
<p>Which factors do you believe are more important than CO2?</p>
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		<title>By: Industry Insider</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1550</link>
		<dc:creator>Industry Insider</dc:creator>
		<pubDate>Mon, 05 May 2008 16:21:19 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1550</guid>
		<description>&lt;p&gt;Scientist - I appreciate the detailed response.  Using the equation you specify, ΔF(1915) = 0.329 and ΔF(1947) = 0.483, so the delta in 1947 is 47% higher than the value in 1915 (and 47% is &quot;a lot&quot; higher in my opinion).  Regarding the rest of your post, I am not discounting the other factors that determine global temperature.  (Rather, I was making the point because there is a perception out there in the public that all of the temperature change since pre-industrial times was caused by CO2, which I think we both agree is not the case.)  As I have said before, while CO2 can affect climate, I believe that effect is less important than other factors, particularly in light of the information discussed here recently regarding the various feedbacks and decadal oscillations.&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>Scientist &#8211; I appreciate the detailed response.  Using the equation you specify, ΔF(1915) = 0.329 and ΔF(1947) = 0.483, so the delta in 1947 is 47% higher than the value in 1915 (and 47% is &#8220;a lot&#8221; higher in my opinion).  Regarding the rest of your post, I am not discounting the other factors that determine global temperature.  (Rather, I was making the point because there is a perception out there in the public that all of the temperature change since pre-industrial times was caused by CO2, which I think we both agree is not the case.)  As I have said before, while CO2 can affect climate, I believe that effect is less important than other factors, particularly in light of the information discussed here recently regarding the various feedbacks and decadal oscillations.</p>
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		<title>By: Scientist</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1549</link>
		<dc:creator>Scientist</dc:creator>
		<pubDate>Mon, 05 May 2008 15:28:50 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1549</guid>
		<description>&lt;p&gt;I think that taking a position on an issue without doing research on it is not productive.  It takes a matter of seconds to calculate forcings from CO2 concentration changes, if you know the equations.  You really should do basic research before deciding what your opinion will be.  If you don&#039;t wish to do research, or don&#039;t have time, then you should not even be forming an opinion, let alone publicly espousing it.  But if you want me to do the work for you on this, then here we go.&lt;/p&gt;

&lt;p&gt;Take the base CO2 concentration as &lt;a href=&quot;http://cdiac.ornl.gov/ftp/trends/co2/lawdome.smoothed.yr20&quot; rel=&quot;nofollow&quot;&gt;283.4ppm&lt;/a&gt;.  One equation for calculating forcing is &lt;a href=&quot;http://www.agu.org/pubs/crossref/1998/98GL01908.shtml&quot; rel=&quot;nofollow&quot;&gt;ΔF = 5.35ln(C/C0)&lt;/a&gt; where C0 is the reference concentration.  In 1915, the concentration of CO2 in the atmosphere was 301.4ppm.  In 1947 it was 310.2ppm.  The forcings are then.. well, do you want to do the calculations?&lt;/p&gt;

&lt;p&gt;What you can then go on to calculate is the expected climate response, if these CO2 forcings were the only forcings operating, and if the climate system was given enough time to reach equilibrium.  The climate sensitivity is generally estimated at about 0.75°C/W/m².  What you should find is that the temperature changes are not huge.  Other effects are comparable.  The solar constant increased by about 0.8 W/m² between 1920 and 1945, giving a forcing of 0.14W/m².  You can calculate the forcing due to the change in CO2 concentrations over the same timescale.  Is it larger or smaller?  What would the expected climate response be from solar forcing in isolation?&lt;/p&gt;

&lt;p&gt;Now, do you think that CO2 concentrations are the only factor in determining global temperatures, or do you think that anyone in climate science thinks this?  It appears that you must, from your statement that the CO2 forcing &lt;i&gt;did not result in warming during the 30-year period after 1947&lt;/i&gt;.  I suggest you look up a TSI reconstruction so you can estimate the solar forcing over this period, compare that with the CO2 forcing, and also consider the effect of volcanoes and anthropogenic aerosols over that period.  How much do you think temperatures should have changed by?  How much did they actually change by?&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>I think that taking a position on an issue without doing research on it is not productive.  It takes a matter of seconds to calculate forcings from CO2 concentration changes, if you know the equations.  You really should do basic research before deciding what your opinion will be.  If you don&#8217;t wish to do research, or don&#8217;t have time, then you should not even be forming an opinion, let alone publicly espousing it.  But if you want me to do the work for you on this, then here we go.</p>
<p>Take the base CO2 concentration as <a href="http://cdiac.ornl.gov/ftp/trends/co2/lawdome.smoothed.yr20" rel="nofollow">283.4ppm</a>.  One equation for calculating forcing is <a href="http://www.agu.org/pubs/crossref/1998/98GL01908.shtml" rel="nofollow">ΔF = 5.35ln(C/C0)</a> where C0 is the reference concentration.  In 1915, the concentration of CO2 in the atmosphere was 301.4ppm.  In 1947 it was 310.2ppm.  The forcings are then.. well, do you want to do the calculations?</p>
<p>What you can then go on to calculate is the expected climate response, if these CO2 forcings were the only forcings operating, and if the climate system was given enough time to reach equilibrium.  The climate sensitivity is generally estimated at about 0.75°C/W/m².  What you should find is that the temperature changes are not huge.  Other effects are comparable.  The solar constant increased by about 0.8 W/m² between 1920 and 1945, giving a forcing of 0.14W/m².  You can calculate the forcing due to the change in CO2 concentrations over the same timescale.  Is it larger or smaller?  What would the expected climate response be from solar forcing in isolation?</p>
<p>Now, do you think that CO2 concentrations are the only factor in determining global temperatures, or do you think that anyone in climate science thinks this?  It appears that you must, from your statement that the CO2 forcing <i>did not result in warming during the 30-year period after 1947</i>.  I suggest you look up a TSI reconstruction so you can estimate the solar forcing over this period, compare that with the CO2 forcing, and also consider the effect of volcanoes and anthropogenic aerosols over that period.  How much do you think temperatures should have changed by?  How much did they actually change by?</p>
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		<title>By: Industry Insider</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1548</link>
		<dc:creator>Industry Insider</dc:creator>
		<pubDate>Mon, 05 May 2008 14:20:20 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1548</guid>
		<description>&lt;p&gt;Scientist writes:&lt;/p&gt;

&lt;p&gt;&quot;Too busy to look it up this morning, but what did the CO2 forcing delta look like around 1915 when the increasing temperature trend started? - being an overt disbeliever when you haven&#039;t done basic research is foolish.&quot;&lt;/p&gt;

&lt;p&gt;I respond:  Characterizing someone&#039;s actions as foolish is not productive - let&#039;s be civil in our discussions.  And you still did not answer my question.&lt;/p&gt;

&lt;p&gt;&quot;I would expect the delta in 1915 was a lot less than +0.6 W/m2 - why would you expect that when you haven&#039;t done any research? You are wrong. Do you know what logarithmic curves look like?&quot;&lt;/p&gt;

&lt;p&gt;I respond:  Then please tell me the correct answer.  If I am wrong, I will admit it.&lt;/p&gt;

&lt;p&gt;&quot;(a value that did not cause increased temperatures in 1947) - replace did not cause with contributed to and your statement is correct.&quot;&lt;/p&gt;

&lt;p&gt;I respond:  Some revised language to better convey my point:  &quot;(a value that did not result in warming during the 30-year period after 1947)&quot;&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p>Scientist writes:</p>
<p>&#8220;Too busy to look it up this morning, but what did the CO2 forcing delta look like around 1915 when the increasing temperature trend started? &#8211; being an overt disbeliever when you haven&#8217;t done basic research is foolish.&#8221;</p>
<p>I respond:  Characterizing someone&#8217;s actions as foolish is not productive &#8211; let&#8217;s be civil in our discussions.  And you still did not answer my question.</p>
<p>&#8220;I would expect the delta in 1915 was a lot less than +0.6 W/m2 &#8211; why would you expect that when you haven&#8217;t done any research? You are wrong. Do you know what logarithmic curves look like?&#8221;</p>
<p>I respond:  Then please tell me the correct answer.  If I am wrong, I will admit it.</p>
<p>&#8220;(a value that did not cause increased temperatures in 1947) &#8211; replace did not cause with contributed to and your statement is correct.&#8221;</p>
<p>I respond:  Some revised language to better convey my point:  &#8220;(a value that did not result in warming during the 30-year period after 1947)&#8221;</p>
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		<title>By: Scientist</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1547</link>
		<dc:creator>Scientist</dc:creator>
		<pubDate>Mon, 05 May 2008 13:10:22 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1547</guid>
		<description>&lt;p&gt;&lt;i&gt;Assuming 100% of the variation from 1910-1943 is natural&lt;/i&gt; - bad assumption.&lt;/p&gt;

&lt;p&gt;&lt;i&gt;Isn&#039;t there a conflict of interest when the AGW promoters create the models, select the data, and then interpret the data, And then tell the world how their science shows severe AGW?&lt;/i&gt; - no, I don&#039;t think there is a conflict of interest when scientists do science.&lt;/p&gt;

&lt;p&gt;&lt;i&gt;Too busy to look it up this morning, but what did the CO2 forcing delta look like around 1915 when the increasing temperature trend started?&lt;/i&gt; - being an overt disbeliever when you haven&#039;t done basic research is foolish.&lt;/p&gt;

&lt;p&gt;&lt;i&gt;I would expect the delta in 1915 was a lot less than +0.6 W/m2&lt;/i&gt; - why would you expect that when you haven&#039;t done any research?  You are wrong.  Do you know what logarithmic curves look like?&lt;/p&gt;

&lt;p&gt;&lt;i&gt;(a value that did not cause increased temperatures in 1947)&lt;/i&gt; - replace &lt;i&gt;did not cause&lt;/i&gt; with &lt;i&gt;contributed to&lt;/i&gt; and your statement is correct.&lt;/p&gt;

&lt;p&gt;&lt;i&gt;And it looks like high temperatures in the 30s and late 90s is when the PDO and the AMO coincide.&lt;/i&gt; - why, then, were 1990s temperatures about 0.5°C higher than 1930s temperatures?&lt;/p&gt;

&lt;p&gt;General note to all: if you think the Heartland Institute or the Register are reliable places from which to inform yourself about science, you&#039;re a fool.&lt;/p&gt;

</description>
		<content:encoded><![CDATA[<p><i>Assuming 100% of the variation from 1910-1943 is natural</i> &#8211; bad assumption.</p>
<p><i>Isn&#8217;t there a conflict of interest when the AGW promoters create the models, select the data, and then interpret the data, And then tell the world how their science shows severe AGW?</i> &#8211; no, I don&#8217;t think there is a conflict of interest when scientists do science.</p>
<p><i>Too busy to look it up this morning, but what did the CO2 forcing delta look like around 1915 when the increasing temperature trend started?</i> &#8211; being an overt disbeliever when you haven&#8217;t done basic research is foolish.</p>
<p><i>I would expect the delta in 1915 was a lot less than +0.6 W/m2</i> &#8211; why would you expect that when you haven&#8217;t done any research?  You are wrong.  Do you know what logarithmic curves look like?</p>
<p><i>(a value that did not cause increased temperatures in 1947)</i> &#8211; replace <i>did not cause</i> with <i>contributed to</i> and your statement is correct.</p>
<p><i>And it looks like high temperatures in the 30s and late 90s is when the PDO and the AMO coincide.</i> &#8211; why, then, were 1990s temperatures about 0.5°C higher than 1930s temperatures?</p>
<p>General note to all: if you think the Heartland Institute or the Register are reliable places from which to inform yourself about science, you&#8217;re a fool.</p>
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		<title>By: kuhnkat</title>
		<link>http://www.climate-skeptic.com/2008/05/multi-decade-cl.html/comment-page-1#comment-1546</link>
		<dc:creator>kuhnkat</dc:creator>
		<pubDate>Mon, 05 May 2008 04:26:05 +0000</pubDate>
		<guid isPermaLink="false">http://climate-movie.com/wordpress/2008/05/multi-decade-cl.html#comment-1546</guid>
		<description>&lt;p&gt;Scientist says that PDO was discussed all through IPCC 4.&lt;/p&gt;

&lt;p&gt;OK, I&#039;ll bite Scientist. So please show us how it is built into their models??&lt;/p&gt;

&lt;p&gt;Oh yeah, they didn&#039;t do any model runs predicting the current PDO temp stagnation or cooling until AFTER the PDO went NEGATIVE!!&lt;/p&gt;

&lt;p&gt;Scientist, does that include the AMO that may be going negative also??&lt;/p&gt;

&lt;p&gt;In a couple years are they going to include the lower solar output we are currently experiencing??&lt;/p&gt;

&lt;p&gt;&lt;br /&gt;
Hey, I bet you could model the earth&#039;s climate for us too, IN HINDSIGHT!!!&lt;/p&gt;

&lt;p&gt;HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA&lt;/p&gt;

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		<content:encoded><![CDATA[<p>Scientist says that PDO was discussed all through IPCC 4.</p>
<p>OK, I&#8217;ll bite Scientist. So please show us how it is built into their models??</p>
<p>Oh yeah, they didn&#8217;t do any model runs predicting the current PDO temp stagnation or cooling until AFTER the PDO went NEGATIVE!!</p>
<p>Scientist, does that include the AMO that may be going negative also??</p>
<p>In a couple years are they going to include the lower solar output we are currently experiencing??</p>
<p>
Hey, I bet you could model the earth&#8217;s climate for us too, IN HINDSIGHT!!!</p>
<p>HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA</p>
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