Bushfire CRC: A repository of information regarding bushfire in Australia

Australia has an interesting system to marshall the collective knowledge of researchers and industry researchers to understand certain problems.  They start a short-term company called a Cooperative Research Centre. Here is some background information on how they work: http://crca.asn.au/about-the-crc-association/about-crcs/

The CRC dedicated to bushfire is here: http://www.bushfirecrc.com/

One of the aspects that I find particularly helpful about the CRC approach is that it uses different types of science to understand a problem like bushfire.  For example, there is social science work that illuminates the social dynamics of how people interpret warnings about fire: http://www.bushfirecrc.com/sites/default/files/managed/resource/fire_note_122_low_res.pdf

There are also more comprehensive technical reports like this one: http://www.bushfirecrc.com/sites/default/files/fire_in_the_landscape_final_report.pdf

Overall, I think the idea of CRCs is a great way to tackle complex problems from multiple angles and with multiple stakeholders.

 

Eucalyptus: What are they and how do they promote fire

Eucalyptus trees are a genus native to Australia (originating 35-50 million years ago when Australia and New Guinea separated from Gondwana) and not typically found outside of antipodean region.  Many individual species of eucalypts are known colloquially as gum trees because of the ubiquitous sap that flows from the trees.  The species has been a poplar export around the world because it grows very quickly.  While the trees have broad leaves, they do not tend to drop them in the autumn, remaining green all year round. Some species of eucalyptus shed their bark every year, which leaves a bare trunk and lots of debris on the ground.  

Eucalyptus trees have very flammable sap, which combined with the bark that accumulates at the tree base creates ideal conditions for ignition.  The alpine ash and mountain ash varieties of trees only regenerate after bushfires. 

Australian mountains in the context of the tectonic plates

Australian mountains in the context of the tectonic plates

Why are the mountains in Australia so short?  Right now Australia sits in the middle of a tectonic plate.  Because it is not located near any plate boundaries, there is little significant faulting that causes mountain building.  The highest altitude in Australia is Mount Kosciuszko in the snowy mountains in the state of New South Wales, which tops out at 2228 m.  By contrast Mountain Elbert, the highest mountain in Colorado reaches up to 4401 m.  Mount Kosciuszko is thought to have experienced Pleistocene glaciation.

General Climate of Australia

A good overview map of the climatic zones of Australia can be seen in a figure from wikipedia:

In terms of rainfall, only the antarctic continent receives less annual precipitation.  The continent average rainfall is 419 mm per year. There are rainfall extremes that diverge from this average.  In the tropical areas of Queensland, the annual precipitation average is 4000 mm.  In Victoria, the median rainfall is 1800 mm. Why is Australia so dry?  The surrounding ocean is very cold, and therefore there is little evaporation of ocean water that would lead to rainfall.  Moreover, the mountains in Australia are pretty short.  When air ascends over large mountains it cools and water condenses generating precipitation, this accounts for all the snow in the Californian Sierra and in the Rocky Mountains.  Short mountains in Australia mean that there is little orographic effect in rainfall generation. Finally, Australia lies in a high pressure zone.

http://soer.justice.tas.gov.au/2003/image/370/   And to put this into a N. American context, this is what the pattern of air circulation looks like in the western Hemisphere.

 

http://www.indiana.edu/~geol105/1425chap4.htm

Bush fires in Australia are typically associated with El Nino and dry windy conditions.

A bit of background on Australia

The first known people to have settled in Australia are known as the aborigines. They are known to have been on the continent since the late Pleistocene epoch (~30,000 years ago). This migration is around the same time as movement of Asians to North America via the land bridge. Australia was likely colonized via sea navigation or possibly as a result of a sea navigation accident. The exact origin of the aborigines is unclear. However, during the initial migration, sea-level was much lower (~200 m) and the Australian continent was 25% larger. In fact, during the late Pleistocene, it would have been possible to walk from the Australian continent to Tasmania or New Guinea on dry land. Dingos, or Australian wild dogs, are one of the lasting biological remnants of the aboriginal migration. 

The first Europeans to come to Australia came with Captain James Cook in April of 1770. Cook left England in August 1768 and returned in 1771. This was not initially a mission to find Australia; it was a mission to Tahiti, which is in the middle of the Pacific Ocean, to observe the transit of Venus across the Sun. Then after that mission was accomplished, Cook opened sealed orders that instructed him to look for a hypothesized continent that scientists were calling Terra Australis. So Cook convinced a Polynesian named Tupaia to come on the ship with him, and Tupaia helped Cook to navigate the southern Pacific. They completely circumnavigated New Zealand and mapped it in complete detail in 1770. The Cook party sailed across to Australia and encountered aborigines in Botany Bay (named for the unique botanical specimans). Botany Bay is just south of modern day Sydney. 

A quick note about Cook, he had two more expeditions, among which he nearly went to Antarctica (sailing into the Antarctic circle), he “discovered” Hawaii, and he was the first person to map North America from California up to Alaska. He was killed by a group of Hawaiians. 

In 1787, Australia was became an official penal colony of England under King George III. And in 1788, eleven ships landed in what is currently known as Sydney harbor. In all 160,000 convicts were sent from England to Australia.

Ecosystem Collapse in Australia during the Pleistocene

http://www.earthmagazine.org/article/ecosystem-collapse-pleistocene-australia

Geology Travel article on Australia

http://www.earthmagazine.org/article/travels-geology-australias-wonders-ocean-desert

http://www.earthmagazine.org/article/travels-geology-twin-coral-reefs-separated-time-western-australia

http://www.earthmagazine.org/article/travels-geology-twin-coral-reefs-separated-time-western-australia

Here is a really nice article on both modern and ancient coral reefs in western Australia.