Purpose: How do we use dendrochronology? Warmup: Finish each item Meteorologists discover ancient climate conditions by many ways: Glaciers shrinking tells us… Sakura occuring late tells us… Analyzing ice layers tells us… Thin tree rings tell us… .
Dendrochronology is the dating and study of annual rings in trees. The word comes from these roots: ology = the study of chronos = time; more specifically, events and processes in the past dendros = using trees; more specifically, the growth rings of trees
Climate is the amount of ______ and ______ measured over a LONG period of time. Tree ring thickness tells us old climate information, both the ______ and the _______ of old years.
Tree rings are striped because…
A single tree ring Top is conifer, bottom deciduous ,,,
Tree rings are striped because…
Three completely different ways to look at this set of rings… This picture of a conifer wood sample shows . The rings display much variation: Three completely different ways to look at this set of rings… This picture of a conifer wood sample shows . The rings display much variation: variation in total ring width: a light and a dark band variation in latewood width: just the dark bands variation in latewood density: darkness of dark band
A fire scarred spruce tree
Narrow rings mean… They occur in… Narrow rings are the most useful of all marker rings. They appear faithfully in almost all of the trees of an area since they are usually caused by climate felt at a regional scale. Depending on the tree species in which they are recorded, they speak of drier/wetter or warmer/colder conditions than those preferred by the species. http://www.yukonenvirothon.com/dendrochronology.html
Buried by a glacier circa 1120 AD Recovering of a slice from a medieval sample located 30 m below the moraine crest. Dendro-dating yields a death-date at 1120 AD - meaning that the glacier reached this level at the beginning of the 12th century. http://www.flickr.com/photos/98204544@N05/9241618498
Rings of trees show insect outbreaks What Tree-Ring Reconstruction Tells Us about Conifer Defoliator Outbreaks Ann M. Lynch
Environ. Res. Lett. 6 (October-December 2011) 045503 doi:10 Environ. Res. Lett. 6 (October-December 2011) 045503 doi:10.1088/1748-9326/6/4/045503Varying boreal forest response to Arctic environmental change at the Firth River, Alaska Laia Andreu-Hayles1,2, Rosanne D'Arrigo1, Kevin J Anchukaitis1, Pieter S A Beck3, David Frank4,5 and Scott Goetz3 http://iopscience.iop.org/1748-9326/6/4/045503/fulltext/
http://www.cpat.org.uk/educate/leaflets/archaeol/archaeol.htm
http://www. wageningenur http://www.wageningenur.nl/en/Expertise-Services/Chair-groups/Environmental-Sciences/Forest-Ecology-and-Forest-Management-Group/DendroLab/Research/Dating-Dendroprovenancing.htm
False Bands/Rings This sample has 2 full rings; the right-most ring has a false band. The false band appears to go through a resin duct. False bands are differentiated from true rings by their cellular structure. This sample is dateable, but NOT by mere ring counting.
. trees, ice core, pollen, sediment ocean, season onset from sakura and lake ice, food, images, oxygen isotopes ,,,
Locally Absent Rings Locally Absent Rings Top part of this photo has 3 full rings. Lower part of this photo has 4 full rings. The wedge that is the 4th ring is "locally absent" from part of this tree. This sample is dateable, but NOT by mere ring counting. Locally Absent Rings Top part of this photo has 3 full rings. Lower part of this photo has 4 full rings. The wedge that is the 4th ring is "locally absent" from part of this tree. This sample is dateable, but NOT by mere ring counting.
I’m Melting!
Global Warming Correlation Between CO2 and Temperature
It is _____________________________________________________ 13. Making a Clinometer 15 Points If you want to know how tall a chair or your desk at school is, you can take a meter stick and measure it. But what if you want to know the height of something really tall like a tree in your schoolyard? Can you think of a way to measure the height of tall things? Here is a method that uses the geometry of right-angled triangle to measure the height of tall objects. Follow the directions and construct a clinometer. Use the clinometer to measure the height of 10 trees. Making a Clinometer found at: http://educ.queensu.ca/~fmc/march2004/tree5_01.html 14. Reading the Rings 5 Points To help figure out what climate the tree grew in and what the environment was like, look at each ring: Thickness How wide a ring is can tell you if the environment was good or bad for the tree to grow in. In years when the amount of rain and temperature were good a tree's rings are wider. In bad years a tree's rings are thinner. Shape If rings become thinner on one side than the other it means the tree is leaning over to one side. High winds or a big storm can cause a tree to lean. Strange Marks Dr. Fir also looks for strange marks, like scars, and other "pieces of evidence." Scars can be left by insects or disease. A forest fire can leave burnt marks. Describe dendrochronology. What is it? How is it done? How is it used to calibrate the C-14 Radioisotopes dating method? Illustrate with a picture. It is _____________________________________________________ It is done by ______________________________________________ ________________________________________________________ It is used to calibrate the C-14 radioisotopes dating method by ______ Illustration of dendrochronology How Old is Old? 1. What are the two types of dating used by archaeologists? Relative Absolute 10. What is dendrochronology? Dendrochronology is a scientific dating method using the rings in trees. 11. Describe how “dendrochronology” is used by archaeologists. Rings change according to climate—scientists match similar rings on artifacts and trees with known ages. It works just like grocery store scanners. 12. What are some advantages and disadvantages of using tree ring dating? Advantages: very accurate—gives exact date Disadvantages: only good for a few thousand years and only in certain places
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