Global warming may cause dramatic 40% decline in vegetation

Australia is the world's most parched continent and its limited water sources have suffered a lot in the last two centuries due to population increase and climate change. Changes resultant of global warming in both precipitation and evaporation rates in the continent are yet to be forecasted.

Deserts or semi-deserts constitute about 70% of the Australian mainland and, as a result of the high evaporation rate, only a very small amount of the rainfall remains as surface runoff to nourish the rivers.

The wetlands are limited to the north, Tasmania, and along the east and the western coasts. They need a continuous natural supply of water to survive and support the flora and fauna they host. Most of the Australian coastal and inland wetlands are at serious risk from plummeting rainfall and escalating evaporation rates.

The Swan coastal plain of Western Australia is facing extinction and the Southern Fleurieu swamps in South Australia are drying up due to dwindling water flows and soaring temperature. The major permanent rivers of Australia - there are only a few of them - are being severely affected by climate change and reductions in the flow.

Southern Australian rivers are particularly affected by less rainfall in winter and greater rates of evaporation. Murray-Darling Basin, the largest of its kind in the continent, expects a reduction of 12-35% in mean flow, by the middle of this century.

In Kakadu wetlands, a World Heritage site, freshwater wetlands are fast becoming saltwater ones; a result of sea level intrusion due to global warming. The Macquarie Marshes of south-eastern Australia is an important breeding area for many water birds and thousands of them inhabit the place as well. Climate change may cause a decline in the wetland's vegetation by 40% and rainfall by a further 15%. Since 1841, the water levels of Lake Bullenmerri, the deepest natural lake in Victoria, have fallen by 20 metres. The falling rate is much faster than the expected decline.

Climate change is a reality now and, in all probability, will accelerate in the future. Its effects on the wetlands, at least the worst among them, can be avoided by taking timely actions such as reducing the production of greenhouse gases.

The preservation of wetlands is important not only for the inhabitants of the place and but also for the whole of Australia. The persistence and diversity of life in the continent depend on it.