Depth: 4 km
Distances: 183 km W of La Laguna, Spain / pop: 150,000 / local time: 04:42:14.5 2020-10-09
28 km WSW of Los Llanos de Aridane, Spain / pop: 20,700 / local time: 04:42:14.5 2020-10-09
Depth: 33 km
Distances: 153 km W of La Laguna, Spain / pop: 150,000 / local time: 04:39:14.7 2020-10-09
11 km SSE of Los Llanos de Aridane, Spain / pop: 20,700 / local time: 04:39:14.7 2020-10-09
Depth: 35 km
Distances: 137 km W of La Laguna, Spain / pop: 150,000 / local time: 04:37:49.2 2020-10-09
17 km SSE of Santa Cruz de la Palma, Spain / pop: 17,000 / local time: 04:37:49.2 2020-10-09
56 km NE of Saint Croix, U.S. Virgin Islands / pop: 50,600 / local time: 21:21:25.3 2020-10-08
The ice-covered Grímsvötn volcano on Iceland produced an unusually large and powerful eruption in 2011, sending ash 20 kilometres into the atmosphere, causing the cancellation of about 900 passenger flights. In comparison, the much smaller 2010 eruption of Eyjafjallajökull led to the cancellation of about 100,000 flights.
Understandably, any mention of another explosive eruption from an Icelandic volcano will raise concerns in the air travel industry, which is currently reeling from the COVID-19 pandemic.
But there are clear signs that the Grímsvötn volcano is getting ready to erupt again. As a result, the authorities have recently raised the threat level for this volcano.
Grímsvötn is a peculiar volcano, as it lies almost wholly beneath ice, and the only permanently visible part is an old ridge on its south side which forms the edge of a large crater (a caldera). And it is along the base of this ridge, under the ice, that most recent eruptions have occurred.
Another peculiarity is that the heat output from the volcano is extraordinarily high (2000-4000 MW), and this melts the overlying ice and produces a hidden subglacial lake of meltwater. This is up to 100 metres (328 feet) deep and has ice up to about 260 metres (850 feet) thick floating on it. Fresh ice is continually flowing into the caldera, where it melts, and so the water level just keeps rising and rising.
This meltwater can escape suddenly, and after travelling southwards beneath the ice for about 45 kilometres it emerges at the ice margin as a flood, which in the past has washed away roads and bridges. Fortunately, the passage of meltwater beneath the ice to its outlet can be tracked, and so roads are closed in good time to avoid travellers getting caught in the flood and killed.
Yet another important peculiarity of Grímsvötn is that it can have a hair-trigger response to pressure. This happens when the meltwater lake drains – removal of the water from across the top of the volcano rapidly reduces the pressure.
This can trigger an eruption – it’s like lifting the lid off a pressure cooker. This has happened many times at Grímsvötn.
Grímsvötn is Iceland’s most frequently erupting volcano, and over the past 800 years some 65 eruptions are known with some certainty. The time gaps between eruptions are variable – and, for example, prior to the larger 2011 eruption there were smaller eruptions in 2004, 1998 and 1983 with gaps of between four and 15 years.
Crucially, and with the next eruption in mind, Grímsvötn appears to have a pattern of infrequent larger eruptions that occur every 150-200 years (for example 2011, 1873, 1619), with smaller and more frequent eruptions occurring roughly once a decade in between.
A high frequency of eruptions at a volcano allows scientists to detect patterns that lead to eruptions (precursors). And if these are repeated each time a volcano erupts then it becomes possible for scientists to be more confident that an eruption is likely to happen in the near future.
It is, however, seldom possible to be precise about the exact day.
Icelandic scientists have been carefully monitoring Grímsvötn since its 2011 eruption, and have seen various signals that suggest the volcano is getting ready to erupt.
For example, the volcano has been inflating as new magma moves into the plumbing system beneath it (think of burying a balloon in the sand and then inflating it). Increasing thermal activity has been melting more ice and there has also been a recent increase in earthquake activity.
So what happens next? Again, based on the pattern observed at past eruptions, an intense swarm of earthquakes lasting a few hours (one to ten hours) will signal that magma is moving towards the surface and that an eruption is imminent. In cases where the hidden subglacial lake drains and triggers the eruption, the earthquakes occur after the lake has drained and just before the eruption.
The smaller Grímsvötn eruptions expend a lot of energy when they interact with water and ice at the surface. That means the resulting ash gets wet and sticky and so falls from the sky relatively quickly.
Ash clouds therefore only travel a few tens of kilometres from the eruption site. This is a good scenario for Icelanders and also for air travel, as it prevents the formation of substantial ash clouds that could drift around and close off airspace.
But will it be a small eruption? If Grímsvötn’s past pattern of occasional large eruptions with more numerous smaller eruptions occurring in between continues into the future, then the next eruption should be a small one (given there was a large one in 2011). And the word “should” is important here – Iceland’s volcanoes are complex natural systems and patterns are not always followed faithfully.The Conversation
Courtesy of sciencealert.com
Nine people were injured, two of them critically, in a major fire that broke out at an Indian Oil Corporation petrol pump near the Raj Bhavan in Bhubaneswar on Wednesday, police said.
Five fire engines along with Odisha Disaster Rapid Action Force personnel doused the flame after fighting it for about two hours, fire department sources said.
The explosion caused by the fire was so loud that it caused people to rush out of the nearby buildings fearing that there was an earthquake.
Police said some nearby shops and houses suffered damages due to the blast.
Under the impact of the explosion several vehicles which were near the site at the time were found to have been thrown away, eye witnesses said.
The petrol pump itself was damaged in the fire, whose cause is yet to be ascertained.
The IOCL evacuated the fuel in two tanks of the petrol pump.
Senior officers of IOCL and the police rushed to the spot and the roads in the area were closed, officials said.
The critically injured have been shifted to SCB Medical College and Hospital in Cuttack, said LD Sahu, director of Capital Hospital, where the rest are being treated.
Union Petroleum Minister Dharmendra Pradhan has ordered a probe into the fire.
Mr Pradhan said he has directed the secretary to the petroleum and natural gas department to discuss with senior officials of the state government and IOCL about the fire and submit a report at the earliest.
I have directed the Petroleum and Natural Gas Secretary to conduct a probe into the fire incident that took place near Raj Bhavan in Bhubaneswar, the Minister said in a Twitter post.
Courtesy of ndtv.com
A rare October heatwave ramped up over Israel on Thursday, bringing blazing temperatures to many parts of the country as an alarmingly hot summer and fall continued to grip the region.
Jerusalem and Haifa were set for a searing 34° C (94° F) on Thursday afternoon, while Tel Aviv was set for a high of 33° (91° F).
The northern cities of Tiberias and Beit She’an and the southern resort town of Eilat were expected to see temperatures as high as 41° C (105° F).
The heat will linger through the weekend, before dipping slightly early next week, though it will remain unseasonably warm.
Average highs in October generally hover between 26° and 28° (79-82°F). In Eilat, the average daily high for the month is 31.1° (88°F), and in Jerusalem it is 25.3° C (77° F).
October heat waves are uncommon but not unprecedented, though they appear to be increasing in recent years. In 2019, temperatures spiked to nearly 40° C (104 °F) in some parts of the country on October 14 and 15. In 2009 and again in 2010, temperatures in late October soared, hitting 35°C (95°F) in Jerusalem.
Experts say the number of hot days in the region is increasing, as well as the length of the hot season, due to global warming.
According to the Israel Meteorological Service, September was the hottest on record across most of the country. September 4 saw record-breaking heat in several cities, and a heatwave lingered for an unprecedented two weeks, only cooling to seasonal averages for a brief respite at the end of the month. Several deaths have been attributed to the heatwaves.
On Wednesday, the European Union’s Copernicus Climate Change Service announced that September was the hottest on record globally. The monitor said 2020 was on pace to match 2016 as the hottest year ever recorded.
The heatwave in Israel catches the country as it is under nationwide lockdown to stem the coronavirus pandemic. It also comes as the country marks the final days of the Sukkot holiday.
Experts recommend staying indoors or in the shade and keeping hydrated during especially hot days.
Courtesy of timesofisrael.com