Beam me to Planet Gore !
Posted on 04/07/2010 7:12:24 PM PDT by SunkenCiv
Oxford University is involved in a research project to unearth 30,000 year old climate records, before they are lost forever. The rings of preserved kauri trees, hidden in New Zealand's peat bogs, hold the secret to climate fluctuations spanning back to the end of the last Ice Age... carbon dating and other analyses of the kauri tree rings. The trees store an immense amount of information about rapid and extreme climate change in the past. For instance, wide ring widths are associated with cool dry summer conditions... Tree rings are now known to be an excellent resource for extracting very precise and detailed data on atmospheric carbon from a particular time period. Therefore this study could help plug a large gap in our knowledge of climate change by extending historical weather records that only date back to the mid-nineteenth century... The research will focus on the last 30,000 years, but some trees date back 130,000 years. The period towards the end of the last Ice Age is particularly difficult to understand. This unique archive of kauri trees is likely to be lost within the next ten years because the timber is so highly-prized for furniture, arts and crafts. Kauri (Agathis australis) are conifer trees buried in peat bogs across northern New Zealand.
(Excerpt) Read more at sciencedaily.com ...
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Gods |
Beware the climate change spin. To all -- please ping me to other topics which are appropriate for the GGG list. |
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Stalagmites reveal past climateThe researchers examined four stalagmites from Crevice Cave, the longest cave known in Missouri, located about 75 miles south of St. Louis. The stalagmites appeared to have been broken by natural forces such as floods or earthquakes and were found about 80 feet below the ground surface, says Dorale. The team determined when the stalagmite layers were deposited, then deduced paleotemperatures and the general types of vegetation growing in the vicinity during that era by examining the carbon and oxygen isotopes within the calcium carbonate. The profile showed that the area had been covered by forest 75,000 years ago, but by 71,000 years ago, it was savannah and by 59,000 years ago, had become a prairie. Between 55,000 and 25,000 years ago, the forest had returned and persisted. Dorale explains that the pattern is consistent with climatological records from the ocean.
by Kristina Bartlett and Devra Wexler
GeoTimes, March 1999
Carbon clock could show the wrong timeA study led by physicist Warren Beck of the University of Arizona discovered an enormous peak in the amount of carbon-14 in the atmosphere between 45 thousand and 11 thousand years ago. Living organisms and some geological features absorb stable carbon-12 and radioactive carbon-14, which are present in the air in a well-known ratio. Scientists use carbon dating to determine when objects ceased to absorb carbon by measuring how much of the carbon-14 - which has a half-life of 5730 years - has decayed. Beck and colleagues tested slices of a half-metre long stalagmite that grew between 45 000 and 11 000 years ago in a cave in the Bahamas. Galactic cosmic rays create most of the carbon-14 in our atmosphere, while solar cosmic rays generate a smaller fraction. The Earth is partially shielded from galactic cosmic rays by its own magnetic field and the solar magnetic field, which fluctuates as the solar cycle proceeds. These effects are predictable and are thought to have changed little in the last million years - which means they cannot explain the glut of carbon-14. The team speculates that a supernova shock wave could have produced a flurry of cosmic rays.
The wrinkle pattern on Helen Thomas’ face could likely reveal much the same thing.
By 71 thousand years ago, the forest had become savannah. Perhaps this was caused by the sudden drop in world temperatures after the Toba supervolcano 74,000 years ago. Colder weather is drier weather. Incidentally, a bad hurricane season is predicted this year as El Nino is over and Atlantic ocean temperatures are already unusually high.
The carbon clock is like me looking at rust on a nail and guessing how old it is.
Oh boy!
ping
Tree rings have been pretty well debunked as a temperature indicator.
” Incidentally, a bad hurricane season is predicted this year as El Nino is over and Atlantic ocean temperatures are already unusually high.”
If you are in the hurricane prediction business, you need to predict a bad season. If you predict a light season and there are many, people will remember your incompetence. If the reverse happens, it turns out that conditions were not as bad as predicted. Works the same for snow predictions.
Okay. I was pessimastic until I found this.
We have ice core data going back this far, so it does make one wonder if the point of this project is to try to erase the evidence of regular climate cycles and replace it with spin. Maybe I'm just too cynical.
spin, spin, it is: “We have ice core data going back this far”
Also - we have living trees that go back 6000 years. and petrified trees that go much farther. and we have peat bogs in Florida with human bodies that go back 8000 years.
Sorry - 30,000 year trees should be available many places, so it is interesting, but no emergency, ‘lost forever’.
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