Our Planet Works In Weird Ways | BBC Earth Science

Recommendable!

Android Earthquake Alerts from your smartphone: A global system for early warning

Amazing stuff! Your smartphone a lifesafer!

"... turned the global network of Android smartphones into a powerful, pocket-sized earthquake detection system to help supplement official warnings systems. Over the last four years, the Android Earthquake Alerts system has detected thousands of earthquakes and sent alerts to millions of people in nearly 100 countries, often giving them the crucial moments they need to take cover before the shaking arrives.

Evaluation of thousands of earthquakes, analysis of specific earthquake examples and direct user feedback allows the system to continuously improve its performance in key areas, like magnitude estimation, making the alerts more effective over time. ...

The accelerometer in an Android phone, the same sensor that flips the screen when it’s turned sideways, can also detect the ground shaking from an earthquake. If a stationary phone detects the initial, faster-moving P-wave of an earthquake, it sends a signal to our earthquake detection server, along with a coarse location of where the shaking occurred.

The system then quickly analyzes data from many phones to confirm that an earthquake is happening and estimate its location and magnitude. The goal is to warn as many people as possible before the slower, more damaging S-wave of an earthquake reaches them. ..."

From the abstract:

"Earthquake early-warning systems are increasingly being deployed as a strategy to reduce losses in earthquakes, but the regional seismic networks they require do not exist in many earthquake-prone countries.

We use the global Android smartphone network to develop an earthquake detection capability, an alert delivery system, and a user feedback framework. Over 3 years of operation, the system detected an average of 312 earthquakes per month with magnitudes from M 1.9 to M 7.8 in Türkiye.

Alerts were delivered in 98 countries for earthquakes with M ≥4.5, corresponding to ~60 events and 18 million alerts per month.

User feedback shows that 85% of people receiving an alert felt shaking, and 36, 28, and 23% received the alert before, during, and after shaking, respectively. We show how smartphone-based earthquake detection algorithms can be implemented at scale and improved through post event analysis."

Android Earthquake Alerts: A global system for early warning "Using aggregated measurements from a global network of Android smartphones, we developed a system that detects earthquakes, delivers early warnings to users, and builds user trust with each successful alert."

Global earthquake detection and warning using Android phones (open access)

Fig. 1. Global distribution of earthquakes detected and alerted.

Study confirms the rotation of Earth's solid inner core within the outer liquid core has slowed since 2010

Amazing stuff! Or how little we still know about our planet and its climate!

More surprising why is this not linked to Climate Change? There is no CO2 or other so called green house gases involved? Caution: satire

"USC scientists have proven that the Earth’s inner core is backtracking — slowing down — in relation to the planet’s surface, as shown in new research published Wednesday in Nature.
Movement of the inner core has been debated by the scientific community for two decades, with some research indicating that the inner core rotates faster than the planet’s surface. The new USC study provides unambiguous evidence that the inner core began to decrease its speed around 2010, moving slower than the Earth’s surface. ..."

From the abstract:

"The solid inner core, suspended within the liquid outer core and anchored by gravity, has been inferred to rotate relative to the surface of Earth or change over years to decades based on changes in seismograms from repeating earthquakes and explosions. It has a rich inner structure and influences the pattern of outer core convection and therefore Earth’s magnetic field. Here we compile 143 distinct pairs of repeating earthquakes, many within 16 multiplets, built from 121 earthquakes between 1991 and 2023 in the South Sandwich Islands. We analyse their inner-core-penetrating PKIKP waves recorded on the medium-aperture arrays in northern North America. We document that many multiplets exhibit waveforms that change and then revert at later times to match earlier events. The matching waveforms reveal times at which the inner core re-occupies the same position, relative to the mantle, as it did at some time in the past. The pattern of matches, together with previous studies, demonstrates that the inner core gradually super-rotated from 2003 to 2008, and then from 2008 to 2023 sub-rotated two to three times more slowly back through the same path. These matches enable precise and unambiguous tracking of inner core progression and regression. The resolved different rates of forward and backward motion suggest that new models will be necessary for the dynamics between the inner core, outer core and mantle."

Study confirms the rotation of Earth's inner core has slowed

USC study confirms the rotation of Earth’s inner core has slowed (original news  release) A new study provides clear evidence that the inner core began to decrease its speed around 2010.

Inner core backtracking by seismic waveform change reversals (open access)

The inner core began to decrease its speed around 2010, moving slower than the Earth’s surface.

Scientists Unravel How the Tonga Volcano Caused Worldwide Tsunamis

Here is another article about one of the curiously and strangely underreported major geological event of the past 100 years or so! The Tonga submarine volcano eruption of January 2022.

Why was this major geological event of the century so little reported? A conspiracy theorist would suggest that this event would have reminded the citizens of the world that perhaps climate is still much more influenced by nature (e.g. solar activity, volcanoes etc.) than by anthropogenic factors! 

This major event will most likely influence earth climate and weather in the coming decades like the Krakatoa eruption before.

"Scientists have now determined that the underwater volcanic eruption in Tonga earlier this year delivered an astonishing 160,900 tons of water vapor to the stratosphere — water vapor that could intensify global warming for years to come, reports Harry Baker for Live Science. This year’s Tonga eruption also cracked open some mysteries about Earth’s past volcanic events. Back in 1883, a volcano on the island of Krakatoa erupted and caused worldwide tsunamis — just as the recent Tonga eruption did. This time, however, geophysicists were finally able to learn how volcanic eruptions cause tsunamis on that global scale"

Scientists Unravel How the Tonga Volcano Caused Worldwide Tsunamis | Quanta Magazine The Tonga eruption in January was “basically like Krakatoa 2.” This time, geophysicists could explain the tiny tsunamis that cropped up all over the planet, solving a 139-year-old mystery about Tonga’s predecessor.

Tonga's eruption injected so much water into Earth’s atmosphere that it could weaken the ozone layer

Half a billion years ago, Earth was on track to become just like Mars. Ancient rocks now show what saved our magnetic field

Amazing stuff! Getting to the core of geomagnetism! 

By the way, a geomagnetic reversal is also due! Plus, the very important geomagnetic field has been weakening for the past 2000 years, but in particular over the past 150 years ""At present, the overall geomagnetic field is becoming weaker; the present strong deterioration corresponds to a 10–15% decline over the last 150 years and has accelerated in the past several years; geomagnetic intensity has declined almost continuously from a maximum 35% above the modern value achieved approximately 2,000 years ago." Climate Change anyone!

"Thank Earth’s magnetic field for all the plentiful riches and diversity of life this planet has to offer. Without it, solar radiation would strip away the atmosphere and oceans, leaving behind a barren landscape. That’s in fact what happened to Mars, once believed to be a “blue” water world covered in a planetary ocean, which eventually turned “red” after it mysteriously lost its magnetic field some four billion years ago. ...
About 565 million years ago, scientists found evidence that the strength of Earth’s magnetic field plummeted to just 10% of today’s strength. If this trend had continued, all life on our planet would have been surely doomed. But right before the so-called Cambrian explosion of multicellular life on Earth, the magnetic field bounced back — and, according to a new study by geologists at the University of Rochester, this is all thanks to some fundamental changes in the inner core. ...

But in just 15 million years — almost a flash in geological time — the magnetosphere bounced back. ... this rapid renewal in magnetic field strength can be explained by the formation of a solid inner core about 550 million years ago, which essentially recharged the molten outer core. Then, some 450 million years ago, the growing inner core’s structure changed yet again, cementing a boundary between the innermost and outermost inner core. ..."

From the abstract:

"Paleomagnetism can elucidate the origin of inner core structure by establishing when crystallization started. The salient signal is an ultralow field strength, associated with waning thermal energy to power the geodynamo from core-mantle heat flux, followed by a sharp intensity increase as new thermal and compositional sources of buoyancy become available once inner core nucleation (ICN) commences. Ultralow fields have been reported from Ediacaran (~565 Ma) rocks, but the transition to stronger strengths has been unclear. Herein, we present single crystal paleointensity results from early Cambrian (~532 Ma) anorthosites of Oklahoma. These yield a time-averaged dipole moment 5 times greater than that of the Ediacaran Period. This rapid renewal of the field, together with data defining ultralow strengths, constrains ICN to ~550 Ma. Thermal modeling using this onset age suggests the inner core had grown to 50% of its current radius, where seismic anisotropy changes, by ~450 Ma. We propose the seismic anisotropy of the outermost inner core reflects development of a global spherical harmonic degree-2 deep mantle structure at this time that has persisted to the present day. The imprint of an older degree-1 pattern is preserved in the innermost inner core."

Half a billion years ago, Earth was on track to become just like Mars. Ancient rocks now show what saved our magnetic field Earth's magnetic field bounced back right in the nick of time around 550 million years ago.

Early Cambrian renewal of the geodynamo and the origin of inner core structure (open access)

Fig. 3: Early Cambrian field renewal and inner core growth.

The 2022 Tonga undersea volcano eruption was one of the largest ever recorded

Be happy this was not an above ground volcano eruption or we would have witnessed another global crisis after Covid-19, the Russian war of aggression in the Ukraine, and global price inflation!

If I am not mistaken, this enormous volcano eruption was barely mentioned in the news!

"A new analysis has verified that the eruption of the Hunga Tonga-Hunga Ha’apai undersea volcano in January 2022 was among the most explosive volcanic eruptions ever recorded. It was the largest volcanic eruption of the 21st century and also the largest eruption since the 1883 eruption of Krakatoa. ...
Hunga Tonga erupted on January 15 of this year after a string of lesser eruptions that started in December 2021, creating a vertical plume that rose more than 50km (30 miles) above the earth’s surface. The eruption triggered a tsunami so severe that it killed two people in Peru and injured two more in California — despite being thousands of miles away."

 

From the abstract:

"The January 2022 Hunga Tonga–Hunga Haapai eruption was one of the most explosive volcanic events of the modern era, producing a vertical plume which peaked > 50km above the Earth. The initial explosion and subsequent plume triggered atmospheric waves which propagated around the world multiple times. A global-scale wave response of this magnitude from a single source has not previously been observed. Here we show the details of this response, using a comprehensive set of satellite and ground-based observations to quantify it from surface to ionosphere. A broad spectrum of waves was triggered by the initial explosion, including Lamb waves propagating at phase speeds of 318.2±6 ms-1 at surface level and between 308±5 to 319±4 ms-1 in the stratosphere, and gravity waves7 propagating at 238±3 to 269±3 ms-1 in the stratosphere. Gravity waves at sub-ionospheric heights have not previously been observed propagating at this speed or over the whole Earth from a single source. Latent heat release from the plume remained the most significant individual gravity wave source worldwide for >12 hours, producing circular wavefronts visible across the Pacific basin in satellite observations. A single source dominating such a large region is also unique in the observational record. ..."

The 2022 Tonga volcano eruption was one of the largest ever recorded

Why the Tongan eruption will go down in the history of volcanology The 15 January blast sent shock waves around the globe and defied scientific expectations. Researchers are now scrambling to work out why.

Surface-to-space atmospheric waves from Hunga Tonga-Hunga Ha’apai eruption (no public access. Google Scholar provides this link to the PDF)

More Underwater Seismometers Are Finally Coming

Posted: 5/24/2019

Much to my surprise, I learnt today that, after decades of trying, finally submarine seismometers are going to be deployed in larger numbers.

Here is the article: Deploying seismometers where they’re needed most: Underwater Geophysicists hope to use some combination of three approaches to remedy the dearth of seismic data from the oceans.

Quotes from the above article (emphasis added):

1. “Whereas about 1900 seismometers have collected data in the ocean over the past 20 years, the nongovernmental International Seismological Centre lists about 11 500 active sensors on land globally” [Shocking!]
2. “The engineering of a modern-day ocean-bottom seismometer (OBS) ... “They’re basically like robots that don’t talk to home for a year, ...” [What? For a year?]
3. “... high-quality OBS costs about $100 000 to build, whereas a land-based seismometer is about one-fifth of that price”
4. “Over the past several years, …. scientists have shown that it’s feasible to attach seismic sensors to fiber-optic cable with a negligible effect on the cable’s reliability. Seismometers known as SMART sensors would collect seismic data using a small fraction of the cable’s power and bandwidth”
5. “ It’s a floating network of seismometers known as MERMAID, or Mobile Earthquake Recording in Marine Areas by Independent Divers. The instruments are mobile, are about a third as expensive as OBSs, and can be deployed in remote locations without the need for a return trip to collect data. They drift and float in the water column listening for earthquakes. Each time they sense one, they record the data, move to the surface, and transmit the information to a satellite. ... This map shows the location in the Pacific of the 25 currently deployed MERMAIDs.” [Only 25 deployed?]

Perhaps, these seismometers will shed more light on e.g. sea level rise in some coastal areas of our globe!

This tidbit confirms once more that Global Warming (a.k.a. Climate Change) is the greatest hoax perpetrated on humanity in generations! We still know so little about the sun and the oceans that this constant indoctrination with the climate religion is unbearable!