Australia is a vast continent and therefore has severaldifferent climate regions, meaning there is a wide range ofenvironments.In the south, where winters can be cold and wet and summers veryhot and dry, the natural landscape is mostly bushland and prone tointense bushfires.Much of the interior is semi-arid or desert so it has very hotdays in summer, little rain and cooler evenings, while winters havemild days but very cold nights. In the south, extending forhundreds of thousands of square kilometres across the GreatAustralian Bight, is the Nullarbor Plain, a vast, treeless plainwhich is very hot and dry in summer but bitterly cold in winter,especially at night, when the wind whips over the plain.The desert ranges from sandy desert and shifting dunes to stony"gibber" plain. Many of the deserts are not completely arid, havingpermanent waterholes and an abundance of low, hardy vegetation aswell as birds, mammals and reptiles. There are vast saltpans in theoutback of South Austraia and less so in other staes andterritories. These saltpans can fill with water once every tenyears or so, supporting thousands upon thousands of waterbirds,then dry up to crusty pans extending for hundreds of squarekilometres.Australia has thousands of kilometres of magnificent beaches,perfect for Surfing. It also has calm, sheltered bays where fishingand watersports are popular. There are colourful coral reefs andfascinating geological formations, relics of an ancient volcanicage. There are high, rugged mountain ranges and rolling, grassyhills.The north is tropical, especially around northern Queensland andthe "Top End", that is, the far north of the Northern Territory.There is a range of thick rainforest along the coast, but inlandthe region is hot, flat grassland which eventually gives way tosemi-arid countryside. This northern region has a marked dry andwet season, which is more clearly defined than the standard fourseasons. The wet, monsoonal season begins around October andextends through to the end of April. Temperatures in the wet seasontend to be higher and humidity is very high.