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Occasionally
during severe storms, lightning will shoot upwards instead of
downwards toward Earth. These rarely seen, highly charged
meteorological events are known as gigantic jets, and they flash
up to the lower levels of space, or ionosphere. While they don’t
occur every time there is lightning, they
are substantially larger than their downward striking cousins.
Images of
gigantic jets have only been recorded on five occasions since
2001, but recently scientists of Duke University in North
Carolina, with a very lucky shot, captured a one-second image
and the electrical fingerprint of huge lightning that flowed 40
miles upward from the top of a storm.
 The
amount of electrical discharge by conventional lightning and
gigantic jets is comparable, but the Gigantic jets travel
farther and faster than conventional lightning because thinner
air between the clouds and the ionosphere provide less
resistance.
Whereas a
conventional lightning bolt follows a six-inch channel and
travels about 4.5 miles down to earth, the gigantic jet recorded
by the scientists contained multiple channels and travelled
about 40 miles upwards. The picture was caught almost by
accident, for the equipment was set to capture another
phenomenon known as sprites, which are electrical discharges
that occur above storm clouds and are coloured red or blue, with
jellyfish-like tendrils hanging down.
China is a very
seismically active area and has had many catastrophic
earthquakes during its history. A joint European and Chinese
team is using satellite radar data to monitor ground deformation
across major continental faults in China to understand better
the seismic cycle and how faults behave.
Using Synthetic
Aperture Radar (SAR), scientists have been able to measure the
ground deformation that occurred during the Wenchuan earthquake
that struck China’s Sichuan Province last May. This technique
generates ’interferogram’ images, which appear as
rainbow-coloured fringe patterns, showing the ground
displacement that occurred during and after the quake. From the
data it was learned that some of the regions on the fault line
did not rupture that much during the earthquake, so scientists
are asking themselves if the energy is still partially locked
and therefore continually accumulating for the next ’big one’.
By combining
the co– and post-seismic study results they are about to answer
the question. If the area is moving slowly after the quake, they
know that it is not accumulating energy, so believe it to be
safe. However, if one area on the fault is not slipping but
there is creeping movement around it, they know that is a bad
sign, and will be watching the situation very carefully.
 A
tiny possum and a giant rat were recorded by scientists as
probable new species on a recent expedition to Indonesia’s
remote and virtually unknown “Lost
World” in the pristine wilderness of western New Guinea’s Foja
Mountains, part of the Great Mamberamo Basin, the
largest unroaded tropical forest in the Asia Pacific Region. The
possum, a Cercartetus pygmy possum, is one of the world’s
smallest marsupials, and the rat is about 5 times the size of a
typical city rat, and seems to have no fear of humans for it
came to the scientists camp several times during the trip.
Bottlenose
Dolphins were only reported 3 times during October, Off Gwennap
Head, Godrevy and Falmouth. Two other reports of unidentified
dolphins were probably also Bottlenose, for one of the sightings
was of about 20 surfing with humans at Polzeath. Three reports
of Common Dolphins, were all off Gwennap Head, as were 5 reports
of Risso's Dolphins. The sight of about 25 Whitebeaked Dolphins
was a surprise for the Seawatch Team at Gwennap on the 9th of
the month.
There were 14
reported sightings of Harbour Porpoises, all off Gwennap and
Runnelstone area, except one at St. Ives. One of the sightings
off Gwennap Head was of about 50 porpoises. 6 sightings of
Basking Sharks were again all off Gwennap Head except one which
was off Port Quin. 2 reports of Ocean Sunfish, 7 Sightings of
Minke Whale and 16 reports of Grey Seals, were all off the
Gwennap Head and Porthgwarra area, which also turned up a large
rorqual whale on the first of the month. |
