A Number of Injured as Rough Air Strikes Delta Flight Landing at Sydney, Australia

Several people have been injured when a Delta aircraft traveling from Los Angeles to Sydney, Australia was hit by significant turbulence this past Friday.

Flight DL41 "experienced a brief period of turbulence" as it landed at Sydney Airport, a company official informed. Four flight attendants required medical attention.

The New South Wales Ambulance Service reported they evaluated five patients, and took a trio to hospital with non-life-threatening injuries that such as spinal discomfort and head pain. Those affected were between their 30s up to the 70s.

It is the newest example of commercial jets experiencing severe turbulence, with researchers saying that global warming is a key driver.

On board were 245 passengers and fifteen staff members on the aircraft, the Delta spokesperson said, clarifying that the plane touched down "without further incident" at Sydney Airport at shortly before 7 a.m. on Friday.

Emergency responders reported they received a call just three minutes before the plane arrived, and ambulances were standing by on the runway.

Why plane turbulence is growing increasingly prevalent - and more severe.

Last year, two dozen individuals were injured when another Delta jet, flying from Salt Lake City, Utah to Amsterdam, Netherlands, hit "considerable" rough air just 120 minutes into the transoceanic journey, and had to make an unscheduled landing.

Recently, those on board on a Singapore Airlines flight experienced a harrowing brief five-second of severe turbulence. An individual died and many were hurt, as those without seatbelts rose out of their seats and fell back down.

Turbulence is not uncommon on aircraft journeys, and while occurrences of rough conditions appear to be increasing, they are remained quite uncommon.

Research indicates that there are approximately 5,000 incidents of severe-or-greater turbulence annually, out of a total of more than 35 million journeys that currently occur worldwide.

Severe turbulence is described as when the up and down movements of a plane passing through disturbed air apply greater than 1.5g-force on your body - enough to propel you from your seat if you did not have on a safety belt.

As climate change alters atmospheric conditions, experts warn that commercial aviation could become more turbulent: shifts in temperature and changing jet streams in the upper atmosphere are projected to increase the occurrence and strength of dangerous in-flight bumps.