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SYDNEY - Immediate reductions in greenhouse gas emissions will not halt the continuing damage to Australia's environment, a federal government researcher warns.
The CSIRO expects Sydney's maximum temperatures to rise 1.6 degrees by 2030 and 4.8 degrees by 2070.
Average rainfall will decrease by 40 per cent and
water evaporation rates will jump 24 per cent by 2040 under the scorching conditions.
By 2050, annual heat-related deaths of people over 65 will increase almost eight times from 176 to 1312.
The results are part of a CSIRO report commissioned by the NSW government and authored by CSIRO researcher Ben Preston.
Dr Preston predicts temperatures will continue to rise causing drought, flooding and heat waves.
"What's important for people to understand is that this is not simply a lot of hand waving, there's quite a bit of scientific research and effort both within Australia and internationally that goes into producing these estimates," Dr Preston told ABC Radio.
"And the problem there is that future climate change is already built into the system.
"So the warming we've been experiencing in recent years is really a function of greenhouse gases we emitted a few decades ago.
"Although there's a promise that large-scale reductions in future greenhouse gas emissions on the international basis will forestall ... large-scale warming by the end of the century, we've already sort of committed ourselves to additional warming and downstream climate change and consequences over the next few decades."
He said while past climate change was "natural in origin", the world's population is now living a "climate of our own making".
"We have to look at this as sort of long-term preventive care for the environment," Dr Preston said.
"Reducing emissions over the next couple of years isn't going to prevent any sort of climate catastrophe from occurring over the near term."
But all measures to combat climate change must go forward which mean burning fewer fossil fuels to reduce greenhouse gas emissions.
And proposed measures to battle the long-standing drought will be crucial to weathering the shortage in more extreme climate conditions.
"Australia has demonstrated in the past that it has quite a significant capacity to cope with rainfall, water scarcity and pretty significant rainfall variability but maintaining a healthy and sustainable water supply over the future independence of climate change is obviously going to require some considerable reforms in terms of how we use water and how we price water," he said.
- AAP