========================================================================= Date: Sun, 13 Dec 1998 08:28:52 -0700 Reply-To: Michael Pardee Sender: Radiocarbon Mailing List From: Michael Pardee Subject: Atmospheric carbon MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit I am a layman with a dislike for sloppy science. I have seen reports in the popular press which disagree widely about the amount of CO2 added to the atmosphere by the burning of fossil fuels, and I believe the good members of the C14-L list can help me sort this out. Reading the archives has helped, but I still have questions: (1) One source ("Radiocarbon Calibration" http://units.ox.ac.uk/departments/rlaha/calib.html) gives the industrial effect as 2% in 1950; how accurately can we determine the industrial effect in the '90s? Has bomb carbon obscured the industrial effect completely in modern samples? (2) The same source indicates the curve has not always been monotonic; what do we know (and what do we guess) about the bigger disturbances? (3) What is the significance of d13C? (4) What conclusions (if any) can reasonably be reached about the role of fossil carbon in the modern carbon cycle, based on c14 data? Thank you in advance for your help. The information is for my personal use, and respondents' privacy will be respected. Reply off-list to michaelt@cybertrails.com seems appropriate. ========================================================================= Date: Mon, 14 Dec 1998 10:19:22 -0700 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Warren Beck Subject: MichaelT's question on anthropogenic CO2 emissions Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Michael, In answer to your question: "I am a layman with a dislike for sloppy science. I have seen reports in the popular press which disagree widely about the amount of CO2 added to the atmosphere by the burning of fossil fuels, and I believe the good members of the C14-L list can help me sort this out. Reading the archives has helped, but I still have questions." There is a vast literature concerning the size and variability of anthropogenic emissions and how they interact with the natural carbon cycle. For more general information you might start with the article by Siegenthaler & Sarmiento (1993), in Nature, v.365, pp119-125. The 1993 IPCC scientific assessment on Climate Change, sponsored by WMO and UNEP would also be a good place to start gathering information on the topic. Both sources should be easily accessable to a non specialist with a scientific background. Cheers, Warren Beck NSF Arizona AMS Facility Department of Physics PAS Bldg. #81 University of Arizona Tucson AZ 85721 Ph#520-621-4277 Fax#520-621-9619 ========================================================================= Date: Wed, 16 Dec 1998 15:59:25 +0000 Reply-To: f.mccormac@qub.ac.uk Sender: Radiocarbon Mailing List From: Paula Jo Reimer Subject: PhD studentship MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=US-ASCII An ESF PhD Studentship is available at The Queen's University of Belfast to further the development of a tunable diode laser spectrometer method for measuring the stable isotopic composition of gases for archaeological and palaeoecological applications. Only EU nationals and residents are eligible for the studentship. The successful candidate must have a good honours degree in Physics or a related field and some experience in designing or troubleshooting scientific apparatus. Experience in spectroscopy and computer interfacing are desirable. Application forms and further details may be obtained form Dr. Gerry McCormac, School of Archaeology and Palaeoecology, The Queen's University of Belfast. Tel. 01232 335141 FAX 01232 315779 e-mail: f.mccormac@qub.ac.uk. Closing date for applications: January 15, 1999 ========================================================================= Date: Mon, 28 Dec 1998 10:42:07 +0100 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Steve Reese Subject: Hans Oeschger passes away Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Prof. Dr. Hans Oeschger passed away on the morning of Christmas Day at the age of 71. As most of you know Hans Oeshger was one of the pioneers of Radiocarbon, inventor of the "Oeschger Counter" and played an important role in the development of the 14C Accelerator at the ETH Zuerich. ========================================================================= Date: Tue, 29 Dec 1998 08:51:41 -0500 Reply-To: Radiocarbon Mailing List Sender: Radiocarbon Mailing List From: Stacy Kozakavich Subject: Preparing soil samples for AMS dating Mime-Version: 1.0 Content-type: text/plain; charset=us-ascii Hello: I would like to obtain AMS dates for charcoal inclusions within six soil samples collected from sub-surface strata ranging in depth from about 30cm to 100cm below the ground surface. Can anyone assist me in finding the safest method of separating the very fine charcoal inclusions from the soil samples? Is flotation an acceptable method, or can it contaminate samples? Stacy Kozakavich Archaeologist Calgary, Alberta Connected to Microsoft Exchange