Weather and climate
Weather and climate refer to different aspects of meteorology.
Weather is the brief, rapidly changing condition of the atmosphere at a particular place and time, usually changing from hour-to-hour and town-to-town, influenced by the movement of air masses.
Climate, on the other hand, is more stable, describing the average weather over at least 30 years. For example, winter is colder than summer, and Melbourne is colder than Darwin. Just as a cricketer's batting average is rarely hit during a particular match, the (average) climate conditions do not always exist in a particular year.
Climate variability and climate change
Climate variability and climate change are different facets of climate.
Climate variability refers to the year-to-year variations around the average conditions, meaning that consecutive summers will not all be the same, with some cooler and some warmer than the long-term average.
Climate change refers to any long-term trends or shifts in climate over many decades, around which climate variability is evident year to year.
Hence, a single warmer or cooler decade on its own is not sufficient evidence to assert climate change is or isn't occurring, but statistically significant changes in average conditions over many decades do provide evidence of a changing climate.
Living in a changing climate
Australians have learned to live with climate variability such as droughts and flooding rains, or hot and cold years, but our coping capacity is limited. We are vulnerable to extreme events, as shown by the economic, social and environmental costs of recent fires, floods, heatwaves, droughts and cyclones.
Human-induced climate change, represents a raft of new challenges for this generation and those to come, through increases in extreme weather events and other changes, such as sea-level rise and ocean acidification. The changing climate is superimposed on natural climate variability, leading to a change in the frequency, intensity and duration of extreme events.
Climate risk profiles will be altered and adaptation will be necessary to manage these new risks. Adaptation includes new management practices, engineering solutions, improved technologies and behavioural change.