时间:2018-12-03 作者:英语课 分类:英语时差8,16


英语课
The deserts of the southwestern United States stretch, in an irregular pattern, from Oregon southward to beyond the Mexican border and from California to West Texas.
  
Although they vary widely in terrain 1 and temperature, these lands share one trait: extreme dryness. 
 
Dryness in the southwest U.S. can be traced to two sources: a high-pressure system called the North Pacific High, and a phenomenon called the rain-shadowing effect of mountains. 
 
The North Pacific High is part of a relatively 2 stable high pressure system in the Pacific Ocean that influences the weather from northern Mexico, to the far-west and Southwest United States. In a high pressure system, air from up above tends to move downward to ground level. As the air descends 3, it grows warmer and its relative humidity drops. Clear skies and dry weather result. 
 
Rain shadow is the result of the prevailing 4 westerly winds losing most of their moisture to the mountain ranges on the western edge of the desert lands. The western Sierra Nevada, for example, receives ten times as much precipitation as areas immediately to the east. 
 
Combined, the North Pacific High and rain-shadowing create an extremely dry climate. Parts of the Sonoran and Mojave Deserts receive only one and a half inches of rainfall a year. When rain does come, it is often in short cloudbursts that dump water on the dry land more quickly than it can be absorbed, resulting in flash floods. During "false" thunderstorms, common during the hot summer months, rain evaporates before reaching the ground.  
 

1 terrain
n.地面,地形,地图
  • He had made a detailed study of the terrain.他对地形作了缜密的研究。
  • He knows the terrain of this locality like the back of his hand.他对这一带的地形了如指掌。
2 relatively
adv.比较...地,相对地
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
3 descends
v.下来( descend的第三人称单数 );下去;下降;下斜
  • This festival descends from a religious rite. 这个节日起源于宗教仪式。 来自《简明英汉词典》
  • The path descends steeply to the village. 小路陡直而下直到村子。 来自《简明英汉词典》
4 prevailing
adj.盛行的;占优势的;主要的
  • She wears a fashionable hair style prevailing in the city.她的发型是这个城市流行的款式。
  • This reflects attitudes and values prevailing in society.这反映了社会上盛行的态度和价值观。
学英语单词
4-Pyridoxate
adaptive predicative coding
aeromagnetic exploration
agrilus auropictus
Algerian Saharan Arabic
Alice-Josephine Pons
Anynet
Asian-Pacific Postal Union
autogreets
ballast scarifier
Barnby Dun
beat someone's head off
blade shielding
buccopharyngeal epithelium
bureau of the census
calculated gas velocity
call-sign
carinal canal
choke block
concealed-carry
conformal cylindrical projection
control integrated circuit
convexedness
cudi deresi
current market-value
cusp beach
cyphonantes
Dirico
disembargo
Divine Liturgy
dollkind
epidermal cancer
equation of radiative transfer
equatorial quantum number
expanding band clutch
facio-cervical lifting
fast-forwardeds
Featherville
film layer
first-naming
fixed-gate generator
fourbis
Frequency shift telegraphy.
Gcaleka
gigaspora pellucida
granitell
gutturalize
high-speed data
holiday homes
infilling well
initial ladders
Jasdorf
khaph
leasehold obligation
leather-wrapped
Ligamentum nuchae
look straight ahead
lymphocytotropic
malamanteaus
melinite
molecular make-up
neriene fusca
newly-publisheds
non-pollutive technology
of wide distribution
olax wightiana wall. ex wight et am.
opposite-field
optical length
ossa wormi
otitis mucosis
pendentive bracketing
polys
posttraumatic epilepsy
predicted values
propellant management device
pullinsi
rayetheon
re-call
roston
running torque-frequency characteristic
salt eutectic
slow-onsets
snecked rubble wall
solution casting
Spruceton
stomachings
Strikes Risks
stubblefield
survey of gender equality in the workplace
taisha
thick-knit
Trojanów
troubetzkoy
Valais, Alps
Verkhnyaya Taymyra
vitamin-e
water violets
wilted point
world market price
xerotropism
xiaojin mini-pills