OK, i will continue with info for Australians. I expect everybody to continue posting with info on their own country.
Think about Australia and its position on the surface of the Earth. Note that the landmass extends from the tropics down through a Mediterranean climate zone into the southern latitudes (this is equivalent to extending north into the Scandinavian countries for a country north of the equator).
A rainfall map of Australia shows only a narrow coastal band extending from the bottom of Victoria then hugging the coast to the tip of Queensland, across the Gulf of Carpentaria to Darwin and just to the north of Broome receives significant rainfall during any one year (assuming you aren’t in the middle of a drought). Another patch of > 125mm pa extends from Perth south to Albany in WA.
Tasmanians have more water than they know what to do with.
The majority of the Australian landmass receives an average of less than 25mm pa.
In general terms you can divide Australia into;
* tropical highland and coastal regions,
* temperate coastal — highland — inland areas,
* alpine and desert areas.
Each environment offers it own set of challenges and factors to consider in a survival situation
Make it your business to know the average number of days of rain per month (The Bureau of Meteorologies excellent calender contains such statistics) for the areas you fly through and get a 7 day forecast before heading off into the great unknown.
Warning the Australian bush is considered one of the roughest and toughest of terrains on this planet due to the lack of free water and the steepness of hillsides among other things.
Broadly speaking the Australian environment outside of built up areas is not conducive to easy survival by an ill-equipped person or group. The chief problem is the lack of reliable potable water. Unless you actively live, work or play in an alpine environment most of us would find this the most challenging environment of all.