Earthquakes

Magnitude 5+ Earthquakes – Global

5.3 Earthquake hits Tarapaca, Chile.

5,000-Year-Long Earthquake-Tsunami Record

The discovery of sediment layers in a seaside cave represents the longest record of tsunamis in the Indian Ocean, and the clearest record of tsunamis anywhere in the world.

When the December 26, 2004 Indian Ocean earthquake occurred off the west coast of Sumatra, Indonesia, the 9.1 magnitude event — the third-largest tremor ever recorded on a seismograph — was so strong that it caused the entire planet to vibrate by as much as 0.4 inches. The quake triggered a series of devastating tsunamis that killed up to 280,000 people in fourteen countries, inundating some coastal communities with 100-foot-tall waves. The tsunamis are now regarded as being among the deadliest natural disasters in all of recorded history.

Motivated to better understand quake and tsunami dynamics, scientists Charles Rubin, Benjamin Horton, and their colleagues have been studying the seismic history of the region. Archaeologist Patrick Daly at the Earth Observatory of Singapore (EOS) suggested that they excavate a sea cave about 22 miles south of Banda Aceh, Sumatra.

Analysis of the find, published in the journal Nature Communications, provides a 5,000-year-long sedimentary snapshot of tsunamis in the region. The record shows that eleven tsunamis were generated between 7,900 and 2,900 years ago by earthquakes along the Sunda Megathrust, a 3,300-mile-long fault running from Myanmar to Sumatra along the floor of the Indian Ocean.

The investigation additionally determined that there were two tsunami-free millennia during the 5,000 years, and one century in which four tsunamis struck the coast. The scientists could see that smaller tsunamis tend to occur relatively close together, followed by long dormant periods. These, in turn, tend to be followed by very strong quakes and tsunamis, such as the one that struck in 2004.

According to the researchers, the 5,000-year record of tsunamis represents the first such discovery in a sea cave, the first record of tsunamis over this long of a period in the Indian Ocean, and the clearest record of tsunamis from anywhere in the world.

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The stratigraphy of the sea cave in Sumatra excavated by scientists from the Earth Observatory of Singapore, Rutgers, and other institutions shows lighter bands of sand deposited by tsunamis over a period of 5,000 years and darker bands of organic material, largely consisting of bat guano.

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Storms and Floods

Tropical Storms – Roundup of Tropical Storms:

In the Central Pacific: Tropical Storm Fernanda is located about 635 mi…1020 km E of Hilo Hawaii and about 825 mi…1330 km E of Honolulu Hawaii with maximum sustained winds…40 mph…65 km/h. Present movement…WNW or 285 degrees at 8 mph…13 km/h.

In the Eastern Pacific: Tropical Storm Greg is located about 1010 mi…1630 km WSW of the southern tip of Baja California with maximum sustained winds…50 mph…85 km/h. Present movement…W or 275 degrees at 13 mph…20 km/h.

Tropical Depression Nine-E is located about 420 mi…680 km S of Puerto Angel Mexico and about 550 mi…885 km SSE of Acapulco Mexico with maximum sustained winds…35 mph…55 km/h. Present movement…WNW or 285 degrees at 13 mph…20 km/h.

In the Western Pacific: Tropical storm 10w (Roke), located approximately 252 nm east-southeast of Hong Kong, is tracking west-northwestward at 20 knots.

Tropical depression 07w (Noru), located approximately 245 nm north of Minami Tori Shima, is tracking westward at 05 knots.

Tropical storm 09w (Kulap), located approximately 675 nm north-northeast of Wake Island, is tracking westward at 18 knots.

Tropical depression 08w (Eight), located approximately 238 nm east-northeast of Da Nang, Vietnam, is tracking westward at 06 knots.

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Nature – Images

Interesting Images

Mars Moon – Phobos

Over the course of 22 minutes, Hubble took 13 separate exposures, allowing astronomers to create a time-lapse image showing the tiny moon Phobos during its orbital trek (white dots) around Mars. The grooves on Mars’s moon Phobos could have been produced by tidal forces—the mutual gravitational pull of the planet and the moon.

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Wildfires

Wildfires – Montana, USA

A series of wildfires burning in Eastern Montana blew up on Thursday and now have torched approximately 48,000 acres — or 75 square miles.

The Bridge Coulee Fire was discovered Wednesday afternoon 16 miles north of Mosby and grew from 2,500 acres Thursday afternoon to over 32,000 acres by late evening.

There are three other fires in Garfield County that are being combined with the Bridge Coulee into the Lodgepole Complex which are estimated to cover nearly 48,000 acres.

The Baker fire, 20 miles north of Sand Springs, has burned 10,000 acres while the South Breaks fire, which is 27 miles northeast of Mosby has burned over 5,000 acres. The third blaze is the Square Butte fire which has burned over 800 acres 19 miles north of Sand Springs.

Disease

Dengue fever – Sri Lanka

Sri Lanka’s dengue epidemic has gone over the 100,000 cases mark with the health ministry putting the tally at 101,698 as of today. This is more than 4-times higher than the average number of cases for the same period between 2010 and 2016.

Dengue Fever – Vietnam

Vietnam has seen in excess of 50,000 dengue fever cases in 2017 to date, including 15 deaths and the capital city of Hanoi has been struck hard in recent weeks by the mosquito borne viral disease, according the Strait Times. The report notes that in just the past week, 1,100 cases have been reported.

Kenya cholera update

In a follow-up on the cholera situation in Kenya, the World Health Organization (WHO) reports a total of 1216 suspected cases including 14 deaths (case fatality rate: 1.2%) have been reported since 1 January 2017.

The cholera outbreak has appeared in Kenya in two waves. The first cholera outbreak reported in 2017 was in Tana River County. The outbreak started on 10 October 2016 and was controlled by April 2017.

A second wave of cholera outbreaks started in Garissa County on 2 April 2017 and was reported later in nine other counties including Nairobi, Murang’a, Vihiga, Mombasa, Turkana, Kericho, Nakuru, Kiambu, and Narok. The outbreak is being reported in the general population and in refugee camps.

Nigeria Cholera Update

Seventeen persons have been confirmed dead in 1,617 reported suspected cases as a cholera outbreak continues to ravage Kwara State in North-central Nigeria.