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Weather Glossary - Y



The interval required for the earth to complete one revolution around the sun. A sidereal year, which is the time it takes for the earth to make one absolute revolution around the sun, is 365 days, 6 hours, 9 minutes and 9.5 seconds. The calendar year begins at 12 o'clock midnight local time on the night of December 31st-January 1st. Currently, the Gregorian calendar of 365 days is used, with 366 days every four years, a leap year. The tropical year, also called the mean solar year, is dependent on the seasons. It is the interval between two consecutive returns of the sun to the vernal equinox. In 1900, that took 365 days, 5 hours, 48 minutes, and 46 seconds, and it is decreasing at the rate of 0.53 second per century. This decrease is due to the slow precession of the Earth's axis of rotation.

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South Burnett clean-up in full swing after storm cells leave damage trail

14:28 EDT

The South Burnett Council says crews have been working around the clock to clear debris after a series of storm cells hit the area in southern Queensland.

Storms in Northern Territory and north Queensland downgrade the national mango crop for 2015/16

14:28 EDT

This season's national mango crop has been revised down 800,000 trays after storms lashed key growing regions.

Goyder's Line moving south with climate change, SA scientists say, forcing farming changes

14:01 EDT

Climate change is moving a line drawn across South Australian maps 150 years ago to indicate the northern boundary of the state's good agricultural land, scientists have said.