* Astronomy

Members Login
Post Info TOPIC: Dendrochronology


L

Posts: 131433
Date:
RE: Dendrochronology
Permalink  
 


Researchers Reconstruct 900 Years of Climatic History Using Tree Rings

Researchers have achieved the first long temperature reconstruction for the eastern Mediterranean using the stable carbon isotopes found in tree rings found in the region.
The study examines the months from January to May in order to target the period in which the trees shift from winter dormancy to springtime reactivation. In doing so, the researchers were able to reveal new insight into the climatic history of the region -- a subject largely shrouded in mystery.

Read more



__________________


L

Posts: 131433
Date:
Tree rings
Permalink  
 


Tree rings go with the flow of the Amazon

University of Leeds-led research has used tree rings from eight cedar trees in Bolivia to unlock a 100-year history of rainfall across the Amazon basin, that contains the worlds largest river system.
The new study shows that the rings in lowland tropical cedar trees provide a natural archive of data closely related to historic rainfall.
Researchers measured the amounts of two different oxygen isotopes trapped in the woods rings: oxygen-16 and the heavier oxygen-18. By looking at the varying amounts of the two isotopes, they could see how the pattern of rainfall changed year by year. This allowed them to see how much it rained over the Amazon basin over the past century.

Read more



__________________


L

Posts: 131433
Date:
RE: Dendrochronology
Permalink  
 


Tree rings can tell region's ancient fire history

Trees can provide secrets about past events, and their rings can especially yield key information about fires, some of which happened hundreds of years ago, a US researcher says.
Charles Lafon, associate professor of geography, who has studied the fire history of forests throughout the southern and central Appalachian Mountains, says that some trees have a lot to tell - one tree he examined endured 14 separate fires through its lifetime.

Read more



__________________


L

Posts: 131433
Date:
Permalink  
 

Tree ring widths more affected by sheep than temperature

Nibbling by herbivores can have a greater impact on the width of tree rings than climate, new research has found. The study, published this week in the British Ecological Society's journal Functional Ecology, could help increase the accuracy of the tree ring record as a way of estimating past climatic conditions.
Many factors in addition to climate are known to affect the tree ring record, including attack from parasites and herbivores, but determining how important these other factors have been in the past is difficult.

Read more



__________________


L

Posts: 131433
Date:
Permalink  
 

Lord of the Tree Rings

Trees are outstanding historians. In fact, scientists dating back to Leonardo da Vinci recognized the value of trees. While others had figured out that you could determine the age of a tree by counting its growth rings, da Vinci went beyond that basic knowledge.
Read more 



__________________


L

Posts: 131433
Date:
Permalink  
 

Tree rings map 700 years of Asian monsoons

Tree-ring data from more than 300 sites in Asia have allowed scientists to piece together a year-by-year history of the region's monsoon rains as far back as 1300 AD.
The new database, called the Monsoon Asia Drought Atlas, is important because the summer monsoon, which affects half of the world's population, is little understood by climate modellers.

Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

Along the mountainous spine of Vietnam grow ancient conifers whose tree rings tell of droughts lasting more than a generation that helped push civilisations towards collapse, a climate change conference heard on Tuesday.
Research by scientists from the United States and Japan has revealed a record of drought in Indochina that goes back more than 700 years by studying tree ring core samples from Fokienia hodginsii, a rare species that lives in Vietnam's cloud forests.
What the samples show are two lengthy droughts between the late 1300s early 1400s, around the time the vast and wealthy Angkor civilisation in modern-day Cambodia collapsed.

Source Reuters

__________________


L

Posts: 131433
Date:
Permalink  
 

Researchers confirm that surface temperatures in the Northern Hemisphere were warmer over the last 10 years than any time during the last 1300 years, and, if the climate scientists include the somewhat controversial data derived from tree-ring records, the warming is anomalous for at least 1700 years.

Read more

__________________
Page 1 of 1  sorted by
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard