On Oct 8, 9:35 am, "Edward K. Ream" <edream...@gmail.com> wrote:
> this thread will, from time to time, highlight primary scientific research > articles. I recently had one of those Aha moments about Science Magazine, namely that just about *every* article in it could be considered as exciting as any Aha I've ever had :-) Indeed, the cleverness, doggedness and significance of each and every article is there to be seen, if I take the trouble to look. As a result, I've become a science junkie: there is no way I'll ever get enough. It's time to subscribe to Nature :-) Here are some recent great articles Part 1: non-controversial Persistent Currents in Normal Metal Rings http://www.sciencemag.org/cgi/content/full/326/5950/272 deals with a quantum mechanical prediction I had never heard of before. What interests me is the fantastic experimental skill involved in measuring tiny currents at low temperatures. The authors measured current using mechanical single-crystal silicon cantilevers in a liquid helium bath(!) Part 2: controversial The deniers want to spread confusion and doubt. Here are some antidotes: Both of the World’s Ice Sheets May Be Shrinking Faster and Faster http://www.sciencemag.org/cgi/reprint/326/5950/217-a.pdf A perspectives article: Monsoons and Meltdowns http://www.sciencemag.org/cgi/reprint/326/5950/240.pdf QQQ The breakthrough of Cheng et al. is that they have achieved unprecedented dating precision, and correlate the monsoon record with ice core and marine records, providing all three with an accurate time scale for the past four ice age terminations. They can thus compare the precise timing of meltdowns with potential causes, such as the amount of sunshine (insolation) that fell on the northern ice sheets in the melting season from June to August, or the concentration of atmospheric CO2 known from trapped air bubbles in ice cores. QQQ Btw, the word "insolation" is one of those words you want to remember. And here is the actual research article (which I highly recommend) corresponding to the perspectives article: Ice Age Terminations http://www.sciencemag.org/cgi/content/full/326/5950/248 The Abstract: QQQ 230Th-dated oxygen isotope records of stalagmites from Sanbao Cave, China, characterize Asian Monsoon (AM) precipitation through the ends of the third- and fourthmost recent ice ages. As a result, AM records for the past four glacial terminations can now be precisely correlated with those from ice cores and marine sediments, establishing the timing and sequence of major events. In all four cases, observations are consistent with a classic Northern Hemisphere summer insolation intensity trigger for an initial retreat of northern ice sheets. Meltwater and icebergs entering the North Atlantic alter oceanic and atmospheric circulation and associated fluxes of heat and carbon, causing increases in atmospheric CO2 and Antarctic temperatures that drive the termination in the Southern Hemisphere. Increasing CO2 and summer insolation drive recession of northern ice sheets, with probable positive feedbacks between sea level and CO2. QQQ Edward --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "leo-editor" group. To post to this group, send email to leo-editor@googlegroups.com To unsubscribe from this group, send email to leo-editor+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/leo-editor?hl=en -~----------~----~----~----~------~----~------~--~---
