Temperature & its variability

Indicator description

Temperature, along with rainfall, is one of the main factors that influences the nature and species composition of ecosystems, as well as the types of agricultural activities that can be carried out in the Australian Capital Region. It is the temperature extremes which are of most interest, as longer-term averages are slow to change in response to climate changes, both natural and human induced such as the enhanced Greenhouse effect. For example, many crops are vulnerable to an "unseasonally late" frost, or an extremely hot day at specific stages in crop growth.

Temperature also affects human comfort; this is reflected in energy usage, as many dwellings and places of work require some heating in the coldest winter months, and/or cooling in the hottest summer months.

There are several measures of temperature variability that can be used to provide information on the condition of the region's climate. These include:

• average annual temperature
• minimum and maximum temperatures averaged over the ten percent of highest and ten percent of lowest temperatures recorded in each year and in each season
• average daily temperature range.

Data for each of these are considered for the current reporting period, and for the longest period for which data are available; wherever possible they are compared to long-term mean values for the period 1961-1990.