Residents of Japan were under a tsunami warning Saturday morning after a nearly 5.0-magnitude earthquake hit just off shore near Kagoshima, Kyushu, Japan. The earthquake was initially measured at 7.0-magnitude, but as the day went on, scientists were able to get a more exact measurement of the earthquake and it was downgraded.
The earthquake occurred off the coast of Japan at around 5:50 a.m., and the tsunami warning continued until nearly 9:00 a.m. Kagoshima and Satsunan islands were both included in the tsunami warning for Japan.
The real concern after the earthquake was how the nuclear power plant in Sendai, Japan, was doing.
"There was no abnormality at the No. 1 and the No. 2 reactors following the quake," said Naoyuki Igawa, a spokesman for Kyushu Electric, to the Japan Times.
Four years ago, a magnitude 8.9 earthquake happened just off the coast of Japan that triggered a tsunami that reached over 20 feet. As a direct result, the nuclear plant in Fukushima suffered from an explosion the next day that caused dangerous radiation to release into the air.
According to Live Science, due to the 2011 earthquake, three of the Fukishima Daiichi plant nuclear reactors malfunctioned.
"The cooling system of nuclear reactor No. 1 at the facility malfunctioned yesterday morning after the 8.9-magnitude earthquake knocked the power out, and an inability to cool down nuclear fuel rods caused a buildup of heat and pressure at the facility. It also drove up radiation to 1,000 times its normal level inside the nuclear reactor's control room."
The warnings were lifted after it became apparent that the only tsunami triggered by the earthquake was roughly 30 cm high, according to the Japan Meteorological Agency.
"We have not received any reports of injuries or damage following the earthquake and tsunami advisory," Tetsuro Shinchi, a Kagoshima Prefectural Government official, told the Japan Times. "I felt a fairly strong jolt, but I have not seen anything unusual."
The United States Geological Survey indicated that the epicenter of Saturday's earthquake was relatively shallow and occurred 160 kilometers (approximately 99 miles) from the town of Makurazaki.
This is not the first earthquake to affect Japan this year. In October, a 5.5 magnitude occurred off the coast of Japan near Fukushima. No injuries were reported then, either.
Japan is used to the occasional earthquake. In fact, according to The Weather Network, the country suffers from 1,500 earthquakes annually. The reason Japan has to deal with that many earthquakes is because it's situated along the Pacific "ring of fire."
"The country lies along the Pacific ring of fire, a zone around the Pacific Ocean where 90 percent of the world's earthquakes strike. The ring of fire is a hot spot for earthquakes because it is situated on top of tectonic plates that trigger seismic activity when they grind together."
"But building codes are rigorous and regular disaster drills are held, helping to ensure that despite their frequency and magnitude, quakes usually pass without loss of life or significant damage to property in Japan."