There's plenty of evidence linking our human activities climate change. Over the last decade we're also moving from projections about change to observation of changes.
The most recent example in Australia is the Weather Bureau and CSIRO State of the Climate report.
It finds all of Australia has experienced warming over the past 50 years.
It's a trend that continues. Australian average temperatures are projected to rise by 0.6 to 1.5 ºC by 2030. If global greenhouse gas emissions continue at current levels, warming is projected to be in the range of 2.2 to 5.0 ºC by 2070.
The picture shows average temperature rises from 1960 to 2009. Source: State of the Climate.