Record-Low IOD Index Values Means a Rainy Winter and Spring for Southern Australia
The Australian Government Bureau of Meteorology announced this week that the Indian Ocean Dipole (IOD) has established a negative pattern. A negative IOD means higher-than-usual rainfall for southern, central, and eastern Australia.
A Negative IOD and Rain
The IOD oscillates between cooler and warmer temperatures in the Indian Ocean. When the IOD is in a negative phase, as it is now, the western Indian Ocean is cooler, while the eastern Indian Ocean is warmer with more precipitation. As of July 5th, the Bureau of Meteorology announced that the IOD index values are the lowest they have been in the past 15 years. They predict that the negative pattern will last throughout Australia’s winter and spring. For southern, eastern, and central Australia, this means above-average rainfall over the next two seasons. Because the index value is the lowest we’ve seen in over a decade, we can likely expect even more rainfall than in a typical negative phase. Temperatures during the day should also be slightly cooler than usual. In northern Australia, on the other hand, you can expect slightly warmer temperatures during both the day and night.
Predictions for La Niña
Scientists believe that the IOD index and El Niño-Southern Oscillation are related, although they are still conducting research to fully understand the link. The Bureau of Meteorology reported that the El Niño-Southern Oscillation is currently in a neutral state. However, temperatures in the tropical Pacific Ocean have been lowering over the past few weeks. Surface temperatures are cooler, and the volume of cooler water below the surface appears to be increasing. This cooler water shows that La Niña may be on its way. The Bureau of Meteorology’s ENSO Outlook believes the chances of La Niña occurring before the end of 2016 are about 50%. If it does occur this year, it will increase rainfall in northern, central, and eastern Australia.
Preparing to Collect Rainwater
The negative IOD phase means heavy rainfall in southern, eastern, and central Australia. If La Niña does occur at the same time, we could see record-setting rainfall throughout Australia. The good news is that if you have a water tank, you’ll be able to collect plentiful rainfall and prepare for the dry season. If you don’t already have a water tank, it may be a good idea to get one now before the rainy weather sets in. At Alkatuff, we would love to help you choose a durable poly water tank that’s made to last through extreme weather. We can connect you to great tank brands such as Rotoplas and Bushmans. If you’re interested in saving rainwater and lowering your water bill, please get in touch with us.