tag:blogger.com,1999:blog-4142988674703954802.post4951509371165440731..comments2024-03-11T04:54:26.827-07:00Comments on THE HOCKEY SCHTICK: New paper finds tropical Atlantic temperatures were up to 2.5C warmer 500-1000 years agoUnknownnoreply@blogger.comBlogger7125tag:blogger.com,1999:blog-4142988674703954802.post-44764880426081464852012-09-08T18:01:41.757-07:002012-09-08T18:01:41.757-07:00http://wattsupwiththat.com/2011/12/31/ssts-cooler-...http://wattsupwiththat.com/2011/12/31/ssts-cooler-now-than-in-the-medieval-warming-period/MShttps://www.blogger.com/profile/06714540297202434542noreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-57503552673940410902012-08-29T18:11:27.015-07:002012-08-29T18:11:27.015-07:00the pertinent supplemental text:
"The result...the pertinent supplemental text:<br /><br />"The resulting multivariate equation results in a calculated<br />core-top temperature of 29 °C for the upper mixed layer at<br />our study site. This is 3 °C warmer than the modern average annual upper mixed layer (30 m depth) temperature for the Bonaire<br />Basin, and 1.4 °C warmer than the maximum seasonal sea surface<br />temperature of 27.6 °C during the fall. For comparison, the calculated upper mixed layer temperature using the Sargasso Sea<br />Mg/Ca:temperature calibration (7) is 25.7 °C, in excellent agreement with the modern annual mean mixed layer temperature of<br />25.6 °C at 30 m depth and with the annual mean sea surface temperature of 26.7 °C (19). The coolest temperatures calculated<br />using the multivariate equation are 21.3 °C at approximately<br />16 ky and 22.2 °C during the Last Glacial Maximum (LGM)<br />(Fig. S5), suggesting a maximum glacial-interglacial temperature<br />gradient of almost 7 °C at our site. This amount of cooling in the<br />western tropical Atlantic is much larger than the estimated cooling of only approximately 3 °C in the western tropical Atlantic at<br />the LGM based on the results of the MARGO project (20).<br />Although the Bonaire Basin may have cooled more than the average western tropical Atlantic because of the influence of upwelling, a cooling of 7 °C at the LGM is too large to be considered<br />realistic. Given that neither the calculated core-top temperature<br />nor the estimated glacial-interglacial temperature gradient seems<br />reasonable using the multivariate temperature equation, we<br />chose to use the Sargasso Sea sediment trap calibration equation<br />when calculating upper mixed layer temperatures for this study"<br /><br /><br />indicates modern mixed layer temps with their calibration of "choice" is 0.1C colder than ~500 years ago. The graph shows the mixed layer with their method of "choice" was warmer 3000 years ago during the Minoan warming period than either 500 years ago during the Little Ice Age or modern temps. There is no indication from either method that modern temps are unprecedented, accelerated, or unnatural. MShttps://www.blogger.com/profile/06714540297202434542noreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-53661247458995782002012-08-29T17:12:38.734-07:002012-08-29T17:12:38.734-07:00Those are referring to the stars on the Y-axis onl...Those are referring to the stars on the Y-axis only, NOT the plot lines. You have mistakenly drawn your own lines in connecting the plot lines to these stars. The actual lines plotted are both for mixed-layer temperatures at around 30m depth, but using DIFFERENT calibration equations. The authors argue that the equation used to plot the blue line is entirely unrealistic, and the stars showing the modern temperatures at both the surface and 30m depth illustrate that the blue line is not correct. If you read in the supplemental text, you will read additional reasons why that equation used for the blue line is incorrect. Look at the red line ONLY (the one the authors say is correct), you cannot say that it was warmer 500 years ago. The species used for the reconstruction can live anywhere between the surface and 30m (the blue star and red star, respectively), so you cannot say with any certainty what the modern temperature for that species should be. If the species is mainly living at around 15m depth, the modern temperature would be somewhere between the two stars, indicating a WARMING over the last 500 years.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-34191684906243448122012-08-28T20:42:37.238-07:002012-08-28T20:42:37.238-07:00Read the graph legend:
Red is a proxy for 30m dep...Read the graph legend:<br /><br />Red is a proxy for 30m depth and blue is a proxy for SST. They are not proxies for the same depth, so one is not "better than" the other and BOTH show a cooling, albeit smaller at depth than the surface, over the past ~500 years.MShttps://www.blogger.com/profile/06714540297202434542noreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-49534459290813614622012-08-28T20:19:01.155-07:002012-08-28T20:19:01.155-07:00You don't understand that figure. I argue tha...You don't understand that figure. I argue that the blue line doesn't make sense. I argue the red line reconstruction is best, and NO, that one doesn't show a cooling over the last 500 years. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-44441500316774632642012-08-24T17:52:23.479-07:002012-08-24T17:52:23.479-07:00Thanks for your reply.
1. The rise in CO2 follow...Thanks for your reply. <br /><br />1. The rise in CO2 follows warming by ~800-1000 years and thus is not the cause. The relatively small changes in CO2 forcing during the period of your study do not explain the temperature changes or the changes in AMOC.<br /><br />2. IR radiation from greenhouse gases cannot warm the oceans due to a penetration depth of a few microns, which only results in evaporative cooling<br /><br />3. While your graph above had a different "point" I am simply pointing out the differences between the proxy temps and the "the modern mean annual temperatures" on your graph. Are you claiming that your graph does not show the "modern mean annual temperatures" were colder than the 2 proxies ~500 years ago?MShttps://www.blogger.com/profile/06714540297202434542noreply@blogger.comtag:blogger.com,1999:blog-4142988674703954802.post-12613142277503472232012-08-24T08:18:18.496-07:002012-08-24T08:18:18.496-07:00I am the author of this paper any you completely m...I am the author of this paper any you completely misunderstood the point of this study! The warming events we discuss take place during a transition out of the last ice age and yes, CO2 was on the rise during this time too. It is terrible how you take the science out of its original context and twist it to what you want to say. In addition, you completely miss interpret the point of that figure from the SI section you show. If anything, the study should make us MORE concerned about climate changes in the near future!Matthew Schmidtnoreply@blogger.com