Download Can You Speak “Weather

Can You Speak “Weather-ese”?
By Ressano Machado
W
inds and barometric pressure are words you
might see or hear on a weather app or the weather
report. Air pressure is the force of air pressing
on everything on the earth’s surface. It is measured with an
instrument called a barometer. Air pressure changes with the
density and temperature of air.
Try this experiment: blow up a balloon and squeeze its opening
so that no air can escape. The air inside the balloon has higher
pressure than the air outside, and pushes the surface of the balloon
outward to give it its round shape. What happens if you let go? The
air inside whooshes out and the balloon soon goes flat. As you let
go, the balloon also starts flying as the high-pressure air rushes out.
That’s physics! Air always moves from areas where it’s under high
pressure to lower pressure. When this happens on a large scale, we
call it wind.
Let’s explore some other weather words that are tied to winds.
Jet streams are fast winds high up in the atmosphere, at about
35,000 feet above sea level … where jets fly! These winds are
caused by the earth’s rotation on its axis, and the sun heating the
atmosphere. Catching a tail wind from a jet stream allows a plane
to travel very quickly. During the 1930s, the jet stream weakened
and moved farther south than normal, robbing the middle part of
the U.S. of much-needed moisture. This condition created the “Dust
Bowl” — a time when severe dust storms and drought ruined farm
crops and the ecology.
A vortex occurs when a liquid or gas spins around an imaginary
axis. You can see vortex examples in satellite pictures of hurricanes,
or when you pull the plug from a bathtub full of water. The polar
vortex is an area of low pressure in the upper atmosphere, normally
centered high over Baffin Island in Canada. It is strongest in winter
due to the large temperature differences between the United States
and the polar areas. The polar vortex was blown far south of its
typical position in 2014, bringing us the third-coldest winter on
record after 1979 and 1899!
El Niño is a weather pattern influenced by higher ocean-surface
temperatures in the Pacific Ocean near the equator. As early as the
1600s, South American fishermen had documented the unusually
warm waters in the ocean around December. When we’re having
an “El Niño year,” there are typically warmer temperatures over the
western and northern United States. Wetter conditions are also likely
for the Gulf Coast and Florida, while the Ohio Valley and the Pacific
Northwest are drier.
Ressano Machado is Senior Lecturer at the University of WisconsinLa Crosse.
Word Search Answer Key
EAFML I EAATSTA I ES I
E I A O T OH E H E R NOHC L H
OGOOE NNMA I S A EECHA
ORNHSD I T S L NCE L A I U
RE T T AME T A L UC I TRAP
I E P C T F N S REDMSP B ND
CN S DH L T OROA A RSODS
I H I S GMB T D T G E G I N RH
FOS S I L F UE L S E TRDOL
T UMO L L GS T S E A NA I RE
E S L F V I CNUE T A V I OUT
OEEEU I I RRPEXTXX L I
PGTGEDEOA I UTYE I TS
GARN L PODSNCGT FDES
MS C NU S A I VNE E NT EOE
RE SD L AS I NNB A I E T ST
L S T S I GO L OROE T EMRV