Page 148 - Super Earth Encyclopedia

SHOCK AND AWE

THUNDERSTORM

Moisture evaporating from warm ground can build
gigantic storm clouds. Moist air rising through each
cloud generates powerful updrafts that toss water
droplets and ice crystals up and down. This produces
static electricity in the cloud, charging it like a giant
battery. Eventually, the cloud reaches an incredibly
high voltage that starts breaking down the electrical
resistance of the air, and faint branched leaders of
lightning move toward the ground. When one makes
contact, the main discharge shoots back up the leader
with a much brighter flash—and a loud crack of thunder.

STORM CLOUD

Most clouds are not very deep,
and float at different levels. But
cumulonimbus storm clouds rise
from near the ground all the way
to the stratosphere, up to 10 miles
(16 km) above ground level. At
this height, the cloud cannot build
up any higher, and frozen cloud
droplets start drifting sideways to
create the broad-topped shape
typical of thunderclouds.

STATS AND FACTS

ELECTRICAL CHARGE FREQUENCY HIGHEST
Thunderstorms can
occur anywhere on The electrical At any given TEMPERATURE
charge in a
time, about 2,000
Earth, but they are cumulonimbus thunderstorms
more frequent in the cloud can exceed occur in different GENERATED ON EARTH
EXTREME WEATHER because they are HEATED AIR The air along STORM CLOUD
100 million volts.
places on Earth.
tropics. In cooler
climates, they are most
common in summer,
fuelled by warm air.
Thunderstorms
the path of the
caused by just one
lightning heats to
big cloud usually
last less than
about 54,000°F
LIGHTNING SPEED
30 minutes.
(30,000°C).
ABOUT
220,000
MPH
(355,000
146 KM/H)

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