FW: New Zealand paleoclimate PhD opportunity

[Katherine HARLE]

Interested candidates are invited to contact 

Anthony Fowler (a.fowler at auckland.ac.nz )  

 
 -----Original Message-----
From: Anthony Fowler [mailto:a.fowler at auckland.ac.nz] 
Sent: Thursday, March 07, 2002 11:47 AM
To: Paleoclimate List
Subject: New Zealand paleoclimate PhD opportunity



PhD Opportunity: EL NINO history recorded in kauri tree-rings 


[please circulate to anyone you thing might be interested - thanks Anthony] 


An opportunity exists to undertake PhD studies with a research team in Auckland, 

New Zealand, investigating the potential for climate reconstruction from kauri tree- 

rings. Recent work has identified a relationship between kauri growth and the El 

Niño - Southern Oscillation (ENSO) phenomenon. Three-year funding has been 

received to investigate this, including provision for one new PhD. A focus on 

climate reconstruction is anticipated, but the scope of the PhD is not pre- 

determined; it will partly depend on the interests and skills of the candidate. The 

position is available immediately. Interested candidates are invited to contact 

Anthony Fowler (a.fowler at auckland.ac.nz ) in the first instance for additional 

details to the brief synopsis provided below. 



Background 


A vast atmosphere-ocean interaction centred on the tropical Pacific Ocean, ENSO 

is one of the most important sources of global-scale natural climate variability. 

Research over several decades has defined many of ENSO's essential 

characteristics and identified strong relationships (teleconnections) with the 

climate of some extra-tropical regions, including New Zealand. However, no 

complete theory is yet capable of explaining all aspects of ENSO. Key 

uncertainties include: 


a) the stability in time of observed 20th century teleconnections; 


b) how the character of ENSO has varied on decadal to millennial time scales, and; 


c) whether ENSO is a late Holocene phenomenon only. 


Resolving these uncertainties will represent a significant advance in understanding 

the global climate system. 


Available instrumental and historical records are not long enough to resolve 

century-scale ENSO variability, nor to ascertain if observed decadal-scale 

variability is typical. Addressing such questions requires high resolution 

(annual or better) proxy records of climate from sources such as tree-rings, ice 

cores and coral. The potential of tree-rings for such purposes has repeatedly 

been demonstrated. However, most tree-ring data with potential for ENSO 

reconstruction come from teleconnection regions, rather than from the Tropical 

Pacific core ENSO region. Because teleconnection patterns are known to vary 

in time, a comprehensive spatial network of proxies is desirable for ENSO 

reconstruction. 


A serendipitous outcome of recent dendroclimatological work on Agathis 

australis (kauri) has been the discovery that kauri carries a significant ENSO 

signal in its growth rings. Combined with a) recent success using computer- 

based crossdating techniques to extend modern kauri tree-ring chronologies 

into the 14th century (individual samples to 911AD), and b) availability of 

abundant sub-fossil kauri material covering the last 40,000+ years, the 

potential exists to investigate the high resolution character of ENSO 

variability at decadal through millennial time scales. Moreover, in the context 

of international collaborative ENSO reconstruction efforts, the northern New 

Zealand location of kauri has considerable significance since it brings a 

"new" teleconnection region into play. 


Anthony Fowler (7 March 2002)