Coral in the Great Barrier reef, ice in the Antarctic and native cypress pines in the wheatbelt can all tell us a lotabout climate change. About 35 palaeoclimate scientists from across Australia andaround the world met at UWA last month to put together their latest data in an effort to reconstruct the climate of the past2,000 years, or ‘recent’ history, as Dr Pauline Grierson says.
Dr Grierson organised the workshop and symposium and saidthe scientists were tyring to put into context changes in rainfall and temperature that have occurred since and prior to theindustrial revolution.
They will be feeding into the next Intergovernmental Panel onClimate Change (IPCC) report in 2014. Dr Grierson explained how coral reefs, ice and trees helpscientists to trace climate changes.
“The structural layers of the ice core and the coral and the ringsinside tree trunks all give us valuable information about rainfall and temperature,” she said. Her area of research, as a botanist,is the tree rings. “We can learn whether it was a wet year or a dry year. A wider ring means more growth, which indicatesmore rain, narrower rings point to drier years. Temperature and rainfall are often linked, and trees grow more when it’s warmand wet.
“You can get really long records from trees that live up to 2,000 years in Tasmania and New Zealand, such as the celery toppine, the huon pine and the famous kauri trees,” Dr Grierson said. “On mainland Australia, it is more of a challenge. A lot ofour common eucalypts and acacias don’t have sharp boundaries separating out growth from year to year. However,my group concentrates on native cypress pines, including theRottnest Island pine, which do have clear annual rings.
”Climate science is an emerging strength at UWA with Premier’sResearch Fellow Professor Malcolm McCulloch concentratingon the issue; Professor Stephan Lewandowsky’sinterdisciplinary group and their communication strategies;the palaeoclimate expertise of Dr Greg Skrzypek; dedicatedacademics in Botany and at the Oceans Institute; and aweather group led by Professor Kevin Judd in Mathematicsand Statistics. “We are building up to a critical mass,”Dr Grierson said.
“We were awarded some funding for this workshop, whichwas matched by the University and Rio Tinto, which also sentsome of their people to the workshop.
”They joined academics and practitioners from New Zealand,the US, CSIRO’s Antarctic and Climate Adaptation Divisions,the Australian Institute of Marine Science in Townsville, climategroups from the universities of Melbourne and New SouthWales, other universities and museums.
They included Dr Joelle Gergis (University of Melbourne) andARC Laureate Fellow Dr Chris Turney (UNSW) who are leadersof Aus2K, the Australian partner in a global climate changeresearch group, Pages (Past Global Changes). They helped runthe workshop.
Dr Grierson said Aus2K’s first task following the UWA meetingwould be a paper reconstructing temperatures in the Australianregion. It would be the first of many papers which would bepublished by this working group in a special issue of the Journalof Climate later this year or early next year.
“Our aim is to synthesise and update climate knowledge in theregion,” she said. “Nearly all of the modeling so far has comefrom the northern hemisphere.
“We know that around 1850, there was period of rapidwarming, which co-incides with the industrial revolution.We want to isolate pre-industrial time so we can see howemissions and pollution affect the climate.”
from UWANews 16 May 2011 pg 7