Download The future under global warming – impacts on Australia

The future under global warming
– impacts on Australia
Many of us won’t be alive to see what global warming brings. The students in the Renters’
household will see the effects of climate change during their lifetime. In particular, they will see
effects on food production, water, our environment and human health. Some of these effects can
and will be mitigated with long-term planning and adaptation to change.
Food production in Australia is expected to change, and our industries will need to respond.
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Fish availability varies with sea surface temperatures, which will increase with climate change.
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Beef and dairy cattle will have lower productivity, higher heat stress and more pests, and will
have less pasture growth to live on.
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Fruit that needs chilling to set, such as apples and stone fruit, may need to be grown in different
regions to where they currently exist, or adopt chemical treatments in place of frosts.
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Australian wine will need to adapt, with some regions becoming unsuitable for the varieties
currently grown, and new regions opening up to viticulture.
Human health will face the following problems:
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Increase in heat-related deaths and illnesses that will far outweigh any possible decrease in
cold-related deaths
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Increase in the potential range and incidence of malaria, dengue fever and similar diseases
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Larger numbers of diarrhoea and gastrointestinal sickness outbreaks
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Increased risk of deaths from drowning due to floods
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Changes in the spread of rodent- and pest-spread diseases
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Impacts on mental health due to social and economic disruption
Australia’s environment is very well adapted to short term variability from season to season and
year to year, but very poorly adapted to long term trends such as climate change. Some plants and
animals will be able to move south or to higher altitudes, but not all.
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Many of our animals will have their habitat reduced significantly or fractured into small pieces.
The most susceptible are those that are already listed as threatened or vulnerable.
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Coral reefs inshore will change to algae-dominated ecosystems with two degrees of warming.
Other reefs will be affected by bleaching events occurring every year by the year 2100.
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Alpine ecosystems are the least able to adapt as there’s no higher they can go. Snowfall is very
sensitive to climate change, with a worst-case scenario of losing 96% by 2070. Alpine plant
distributions are determined by summer temperatures. Animals that are dependent on snow
cover for hibernation or protection from predators will decrease in numbers.
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Highland rainforests will lose up to 50% of their area, though lowland rainforest may increase
in area. Birds and animals dependent on this environment will lose between 60 and 90% of
their habitat.
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Coastal wetlands will be lost to sea level rises. Other wetlands will need to adapt to reduced
rainfall, increased nutrient and sediment loading and increased erosion. There are much greater
pressures on wetlands than climate change, however climate change could be the straw that
breaks the camel’s back.
| | Carbon Cops : The future under global warming – impacts on Australia
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Native forests may change substantially, with a quarter of Australian gum trees
restricted to just a one-degree annual temperature range. Change in rainfall regimes
will also impact which forest species can continue. Leaf-eating animals and insects will
decrease as tree leaf chemistry changes in response to increased concentrations of
carbon in the air.
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Rivers will be most affected by an increase in extreme events - floods and droughts. More
frequent droughts will place a greater pressure on a river’s ability to recover. There will be
more frequent algal blooms due to lower water flows and higher water temperatures.
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Weeds and pest animals will increase their impact under global warming.
n Climate change: an Australian guide to the science and potential impacts
www.greenhouse.gov.au/science/guide/
n Climate change impacts on Australia
www.csiro.au/resources/pfbg.html
n Australian Climate Change Science Program
www.csiro.au/org/pst6.html
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| | Carbon Cops : The future under global warming – impacts on Australia