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Strong and shallow M6.6 earthquake hits Andreanof Islands, Alaska
A strong and shallow earthquake registered by the USGS as M6.6 hit the Andreanof Islands, Aleutian Islands, Alaska at 21:57 UTC on August 15, 2018. The agency is reporting a depth of 31.6 km (19.6 miles). EMSC is reporting M6.6 at a depth of 40 km (24.8 miles). According to the USGS, the epicenter was located 41 km (25 miles) S of Tanaga volcano, 108 km (67 miles) WSW of Adak (population 332), Alaska and 1 477 km (918 miles) ESE of Klyuchi (population 10 000), Russia. There are no people living within 100 km (62 miles). Based on all available data, there is no tsunami threat from this earthquake, PTWC said. The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage. Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are…

Southern hemisphere produced its largest wave on record

Southern hemisphere produced its largest wave on record

A massive 23.8 m (78 feet) high wave has been measured near Campbell Island, New Zealand on May 9, 2018, making it the largest wave ever recorded in the southern hemisphere.
A new ocean buoy, installed March 2, 2018 and located about 640 km (400 miles) south of New Zealand's South Island, measured a maximum wave height of 23.8 m (78 feet). The previous record for the southern hemisphere was a 22.03 m (72 feet) high wave registered off the Australian state of Tasmania in 2012.
Credit: MetOcean
"This is a very exciting event and to our knowledge, it is the largest wave ever recorded in the southern hemisphere," Dr. Tom Durrant, a senior oceanographer at the MetOcean, part of New Zealand's Met Service, said.
"Our own previous record was one year ago when we measured a 19.4 m (63.6 feet) wave, and before that, in 2012 an Australian buoy recorded a maximum individual wave (Hmax) of 22.03 m. So, this is a very important storm to capture, and it will add greatly to our understanding of the wave physics under extreme conditions in the Southern Ocean."
"The Southern Ocean is definitely the most under-observed ocean in the world. The region accounts for about 22% of the planet's oceans, and it's the most energetic part of the world's oceans in terms of waves," he said.
This solar-powered buoy samples the waves for just 20 minutes every three hours to conserve its solar-powered battery and then sends the data via a satellite link. During that 20 minute recording period, the height, period and direction of every wave are measured and statistics are calculated.
"It's very probable that larger waves occurred while the buoy was not recording. They may have actually reached more than 25 m (82 feet) if the forecasts were correct," Durrant said.
While this wave was large, it's not a world record.
Furthermore, the World Meteorological Organization doesn’t measure maximum wave height, or, the largest individual wave.
It measures significant wave height, which is meant to represent general ocean conditions and measures the average of the waves. The WMO certified a world record for significant wave height in the North Atlantic in 2013 at 19 m (62 feet).
Significant wave height for May 9 in the Southern Ocean where the abovementioned buoy is located was 14.9 m (48.9 feet), which is also southern hemisphere's record.
Featured image credit: MetOcean

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