New Technique to Detect Storms, Predict Weather Changes

A woman stands in falling snow in front of an electronic sign displaying the weather forecast in Times Square in New York City on Jan. 26, 2015. Reuters
A woman stands in falling snow in front of an electronic sign displaying the weather forecast in Times Square in New York City on Jan. 26, 2015. Reuters
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New Technique to Detect Storms, Predict Weather Changes

A woman stands in falling snow in front of an electronic sign displaying the weather forecast in Times Square in New York City on Jan. 26, 2015. Reuters
A woman stands in falling snow in front of an electronic sign displaying the weather forecast in Times Square in New York City on Jan. 26, 2015. Reuters

A team of researchers from the Universities of Pennsylvania in the US and Almería in Spain, and AccuWeather, Inc. has developed a new computer model that can help forecasters recognize potential severe storms more quickly and accurately.

According to the German News Agency, the new computer model relies on artificial intelligence that detects rotational movements in clouds from satellite images.

When forecasting weather, meteorologists use a number of models and data sources to track shapes and movements of clouds that could indicate severe storms. However, with increasingly expanding weather data sets and looming deadlines, it is nearly impossible for them to monitor all storm formations, especially smaller-scale ones, in real time.

The Science Daily website cited Steve Wistar, senior forensic meteorologist at AccuWeather, saying that having this tool to point the eye toward potentially threatening formations could help in making a better forecast.

In their study, the researchers analyzed more than 50,000 historical weather satellite images. In them, experts identified and labeled the shape and motion of "comma-shaped" clouds that can lead to severe weather.

Then, the researchers fed the artificial intelligence system with these images, in order to teach it how to automatically recognize and detect the comma-shaped clouds in satellite images. The computers can then assist experts by pointing out in real time where to focus their attention in order to detect the onset of severe weather.

The researchers found that their method can effectively detect pre-storm clouds with 99 percent accuracy, at an average of 40 seconds per prediction. It was also able to predict 64 percent of severe weather events, outperforming other existing severe-weather detection methods.



Alien Planet Lashed by Huge Flares from its 'Angry Beast' Star

File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
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Alien Planet Lashed by Huge Flares from its 'Angry Beast' Star

File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger

Scientists are tracking a large gas planet experiencing quite a quandary as it orbits extremely close to a young star - a predicament never previously observed.

This exoplanet, as planets beyond our solar system are called, orbits its star so tightly that it appears to trigger flares from the stellar surface - larger than any observed from the sun - reaching several million miles (km) into space that over time may strip much of this unlucky world's atmosphere, Reuters reported.

The phenomenon appears to be caused by the planet's interaction with the star's magnetic field, according to the researchers. And this star is a kind known to flare, especially when young.

"A young star of this type is an angry beast, especially if you're sitting as close up as this planet does," said Netherlands Institute for Radio Astronomy astrophysicist Ekaterina Ilin, lead author of the study published in the journal Nature.

The star, called HIP 67522, is slightly more massive than the sun and is located about 407 light-years from Earth in the constellation Centaurus. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).

This star and planet, as well as a second smaller gas planet also detected in this planetary system, are practically newborns. Whereas the sun and our solar system's planets are roughly 4.5 billion years old, this star is about 17 million years old, with its planets slightly younger.

The planet, named HIP 67522 b, has a diameter almost the size of Jupiter, our solar system's largest planet, but with only 5% of Jupiter's mass. That makes it one of the puffiest exoplanets known, with a consistency reminiscent of cotton candy (candy floss).

It orbits five times closer to its star than our solar system's innermost planet Mercury orbits the sun, needing only seven days to complete an orbit.

A flare is an intense eruption of electromagnetic radiation emanating from the outermost part of a star's atmosphere, called the corona. So how does HIP 67522 b elicit huge flares from the star? As it orbits, it apparently interacts with the star's magnetic field - either through its own magnetic field or perhaps through the presence of conducting material such as iron in the planet's composition.

"We don't know for sure what the mechanism is. We think it is plausible that the planet moves within the star's magnetic field and whips up a wave that travels along magnetic field lines to the star. When the wave reaches the stellar corona, it triggers flares in large magnetic field loops that store energy, which is released by the wave," Ilin said.

"As it moves through the field like a boat on a lake, it creates waves in its wake," Ilin added. "The flares these waves trigger when they crash into the star are a new phenomenon. This is important because it had never been observed before, especially at the intensity detected."

The researchers believe it is a specific type of wave called an Alfvén wave, named for 20th century Swedish physicist and Nobel Prize laureate Hannes Alfvén, that propagates due to the interaction of magnetic fields.

The flares may heat up and inflate the planet's atmosphere, which is dominated by hydrogen and helium. Being lashed by these flares could blast away lighter elements from the atmosphere and reduce the planet's mass over perhaps hundreds of millions of years.

"At that time, it will have lost most if not all the light elements, and become what's called a sub-Neptune - a gas planet smaller than Neptune," Ilin said, referring to the smallest of our solar system's gas planets.

The researchers used observations by two space telescopes: NASA's TESS, short for Transiting Exoplanet Survey Satellite, and the European Space Agency's CHEOPS, short for CHaracterising ExOPlanet Satellite.

The plight of HIP 67522 b illustrates the many circumstances under which exoplanets exist.

"It is certainly no sheltered youth for this planet. But I am not sad about it. I enjoy diversity in all things nature, and what this planet will eventually become - perhaps a sub-Neptune rich in heavy elements that did not evaporate - is no less fascinating than what we observe today."