dechronology ,master chronology

1. Tree ring analysis

2. Each year, the tree forms new cells,
arranged in concentric circles called annual
rings or annual growth rings. These annual
rings show the amount of wood produced
during one growing season .

3. A cross section of a tree shows much
more than its age!
Diameter growth is particularly sensitive to
fluctuations in the environment:
1. moisture in the soil and air
2. temperature
3. sunlight

4. Very broad rings generally indicate a good
growing year.

5. Similar patterns occur in the rings of
different tree species over a large
geographic area due to variations in the
amount of annual perception .
Years in which adequate precipitation
occurs produce wider rings of growth ,
but years of drought produce much
narrower rings .

6. The inner portion of a growth ring is
formed early in the growing season, when
growth is comparatively rapid (hence the
wood is less dense) and is known as “early
wood”.
The outer portion is the “late wood” (and
has sometimes been termed “summer
wood”, often being produced in the
summer, though sometimes in the
autumn) and is denser .

7. It is possible to study ring sequences that go
back to several thousands years

8. 1.master chronology:
A complete sample of rings dating back as
far as possible .
The scientists to trees the first one which
is old and the second older than the first
and the rings of the center of the older
tree are matched with those toward
outside in the first tree

9. 2.Dendrochronology :
(dendron= tree, chronos = time) is a scientific
method that uses tree-ring sequences to date
annual growth rings of plant to their exact year
of formation. It is applied in several scientific
fields, namely archaeology, climatology,
geomorphology, glaciology, hydrology, fire
history, entomology.

10. Dendrochronology it is the study of both
visible and microscopic details of tree rings.
Uses :
1 tree ring analysis has been extremly useful in
investigation of prehistoric sites of native Americans in
the southeast
2.tree ring data are also useful in other disciptions
including ecology to study changes in forest community
over time
3. Environmental science to study the effects of air
pollution on tree growth
4. ecology to date the earthquakes and volcanic eruptions

11. Studying the tree rings across several
thousand years helps the researchers
determine the natural pattern of global
temperature fluctuations. They are not
sure how much of the recent warming is
the result if human influence rather than
natural climate variability

12. Done by
Mary Hijazin 
I am sure that you have many questions …
and you are welcome to ask 